The standard applies to cryogenic, cryogenic-vacuum equipment operating with oxygen, including medical, nitrogen and other air separation products, and establishes general technological requirements for methods for removing fatty contaminants from the surface of products (degreasing). The standard does not establish requirements for product depreservation processes.

Designation:	OST 26-04-312-83
Russian name:	Equipment degreasing methods. General requirements for technological processes
Status:	replaced
Replaces:	OST 26-04-312-71 “Oxygen equipment. degreasing methods. Applied materials»
Replaced by:	STP 2082-594-05 “Methods for degreasing equipment. General requirements for technological processes"
Text update date:	05.05.2017
Date added to database:	01.09.2013
Date of entry into force:	01.01.2005
Approved:	11/29/1983 Minkhimmash of the USSR (USSR Minkhimmash 11-10-4/1685)
Published:	NPO Cryogenmash (1983)
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Amendment No. 2 to this OST has been amended

Industry standard

OST26-04-312-83

Equipment degreasing methods. General requirements for technological processes

(put into effect by the letter of the Technical Department of Minkhimmash dated November 29, 1983 N11-10-4 / 1685)

Instead of OST26-04-312-71

This standard applies to cryogenic, cryogenic-vacuum equipment and equipment operating with oxygen, including medical, nitrogen and other air separation products, and establishes general technological requirements for methods for removing fatty contaminants from the surface of products (degreasing).

The standard does not establish requirements for the processes of depreservation of products.

Explanations of the terms used in this standard are given in the reference.

1.6. Compliance of the content of fatty contaminants with the established standards is confirmed by a mark in the control-route chart, in the technological passport of the product or in other technical documentation. On the basis of these documents, marks are entered into the product passport, for example: "The content of fatty contaminants does not exceed the standards established by GOST 12.2.052" or "fat-free".

1.7. The preparation and implementation of all degreasing work must be supervised by a responsible person appointed by a written order of the administration, who must be fully responsible for the observance of the degreasing technology, the implementation of timely technical control and the safety of the work.

2. Technical requirements

2.1. Material Requirements

2.1.1. Solvents or aqueous cleaning solutions should be used to degrease the equipment. The need to use solvents or aqueous cleaning solutions should be indicated in the technological documentation.

2.2. Solvents

The used solvents of groups 1 and 2, used at a temperature of 10-20 ° C, depending on the detergent and physico-chemical properties, are given in table. one.

Change No. 1, approved by the Deputy Minister of Chemical and Petroleum Engineering on January 4, 1987, changes have been made to subparagraph 2.2.2 of this OST, which shall enter into force on July 1, 1987.

2.2.2. When degreasing other materials, except those indicated in Table. 1, tests should be carried out for corrosion compatibility with solvents and for residual greasy contaminants.

Scope of solvents

Name of solvents	Residual content of fatty contaminants, mg/m 2 , no more	Application area
Group 1
Freon 113 GOST 23844
Freon 114V2 GOST 15899
Trichlorethylene GOST 9976
Tetrachlorethylene TU 6-01-956
Trichlorethylene GOST 9976 with stabilizer STAT-1-1% TU 6-01-927		For products made of steel, cast iron, copper, aluminum and alloys based on iron, copper, nickel, aluminum
Tetrachlorethylene TU 6-01-956 with stabilizer STAT-1-1% TU 6-01-927
Group 2
Nephrases S2-80/120 and SZ-80/120 GOST 443		For products made of any metals and alloys
Nefras-S 50/170 GOST 8505 (distilled)
Gasoline solvent for the paint and varnish industry (white spirit) GOST 3134	1000	For preliminary removal of fatty contamination of products from any metals and alloys

2.2.3. The quality of the solvent must fully meet the requirements of regulatory and technical documents for the solvent and is confirmed by the manufacturer's certificate.

Solvents supplied for degreasing must be checked before use according to the indicators specified in the mandatory.

2.2.4. Solvent degreasing is carried out 1-2 times depending on the shape of the parts and the required quality of degreasing. When carrying out double degreasing, the residual content of fatty contaminants can be taken equal to the upper limit given in table. 1 without control.

Permissible content of fatty contaminants

On the surface, mg/m 2 , no more	In solvents, mg/dm 3 , no more

Compositions of aqueous cleaning solutions and degreasing regimes

Compositions of aqueous cleaning solutions		Degreasing modes		Residual content of fatty contaminants, mg/m 2	Application area
components of aqueous cleaning solutions and detergents	quantity, g / dm 3	temperature °C	degreasing ratio
Composition 1		from 60 to 80	twice	from 15 to 50	For steel, cast iron, copper and alloys based on iron, copper and nickel
Sodium phosphate, (trisodium phosphate),
GOST 9337
GOST 201
Detergent*
Composition 2				from 10 to 50
Sodium hydroxide (caustic soda)
GOST 4328
GOST 22 63
GOST 9937
GOST 201
Liquid sodium glass
GOST 13078
Detergent*
Composition 2		from 60 to 80	twice	from 15 to 50
Liquid sodium glass
GOST 13078
Detergent*
Composition 4		from 55 to 60		from 10 to 50	For products made of steel, cast iron, copper and alloys based on iron, copper and nickel, with increased requirements for the absence of deposits on their surface
Trilon-B
GOST 10652
Sodium nitrite technical
GOST 19906
Sodium phosphate (trisodium phosphate)
GOST 9337
GOST 201
Detergent*
Detergent ML-72		from 60 to 80		from 20 to 50	For steel, cast iron, copper and alloys based on iron, copper and nickel
TU 84-348
Synthetic detergent MS-8		from 70 to 80
TU 6-15-978
Detergent KM-2		40 to 50			For steel, cast iron, copper, aluminum and alloys based on iron, copper, nickel, aluminum
TU 6-18-5
		from 60 to 70	twice	from 20 to 50	For steel, cast iron, aluminum and alloys based on iron, nickel, aluminum
TU 38-10761
Detergent technical synthetic VIMOL				from 5 to 50	For products made of copper and its alloys
TU 38-10761
Detergent technical TMS-31				from 20 to 50	For products made of steel, cast iron and alloys based on iron, nickel, aluminum
TU 38-107113
		from 70 to 80	once	from 5 to 50
TU 38-10960
Detergent technical Vertolin-74			twice		For steel, cast iron, copper and alloys based on iron, copper and nickel
TU 38-10960
			once		For products made of aluminum and its alloys
TU 6-1816
Aluminum alloy degreaser (OSA)		from 70 to 80	twice	from 20 to 50	For steel, cast iron, copper and alloys based on iron, copper and nickel
TU 6-1816
Detergents for household chemicals**		from 60 to 80

______________________________

*One of the following substances is used:

Surfactant Neonol AF9.6. TU 38.50724 (20g / l) or Neonol AF9.12 TU 38.10362 (5g / l), sintanol DS-10 according to TU 6-14-577 - 5 g / dm 3; non-ionic preparation synthamide 5 according to TU 6-02-640 - 5 g/dm 3 .

** When using solutions with household detergents, it is mandatory to inspect fat-free products after washing and drying. If dry residues of cleaning solutions are found, they must be removed.

2.3.3. The components of aqueous cleaning solutions must comply with the requirements of the regulatory and technical documents specified in.

2.3.4. For the preparation of aqueous cleaning solutions, drinking water is used according to GOST 2874. The use of water from the circulating water supply system is not allowed.

2.3.5. When degreasing products from materials other than those specified in , they should be tested for corrosion compatibility with aqueous cleaning solutions and for the achievable cleanliness of degreasing.

2.3.6. For washing products made of ferrous metals, after degreasing with aqueous detergent solutions, it is recommended to use water with the addition of a corrosion inhibitor - technical sodium nitrite according to GOST 19906 in an amount of 2 g / dm 3 of water.

3.3. When carrying out degreasing of cryogenic vessels, if the presence of a person in them is required, the requirements of the "Temporary standard instruction for the organization of safe gas hazardous work at enterprises of the USSR Ministry of Chemical Industry", approved by the USSR State Mining and Technical Nazor and the MHPSSR, must be observed. Before carrying out work on degreasing cryogenic vessels that were in operation, they must be warmed up to temperatures in the range of 12-30 ° C and ventilated. Work should be carried out only when the oxygen content in the air inside the vessels is in the range from 19 to 23%.

In the organization conducting degreasing, the instructions for carrying out these works must be approved in accordance with the established procedure.

3.4. Degreasing of individual parts by immersing them in baths with solvents should be carried out in apparatus with a closed or semi-closed degreasing cycle, equipped with local ventilation and excluding the ingress of solvent vapors into the air of industrial premises. At the same time, it is necessary to create continuity in the process of degreasing, drying and unloading parts. Drainage of the solvent from the equipment and baths must be carried out in closed vessels through pipelines.

3.5. When degreasing equipment with group 1 solvents (see ), it is necessary to ensure the tightness of the equipment in which degreasing is performed.

3.6. Air emissions after drying and blowing must comply with GOST 17.2.3.02.

3.7. The ventilation of the premises must ensure that the requirements for the air of the working area are met in accordance with GOST 12.1.005.

Table 4

Maximum permissible concentrations of solvents in the air

Name of solvents	The value of the maximum permissible concentration, mg / m 3	Hazard Class
Trichlorethylene
Tetrachlorethylene
Freon 113	3000
Freon 114V2	1000
Gasoline-solvent for the rubber industry (in terms of C)
Nefras-S 50/170
White spirit (in terms of C)

Amendment No. 1, approved by the Deputy Minister of Chemical and Petroleum Machine Building on January 4, 1987, amended paragraph 3.8 of this OST, effective from July 1, 1987.

3.8. Analysis of air samples for the content of harmful substances should be carried out according to the methods developed in accordance withGOST12.1.014 and GOST12.1.016, guidelines and other regulatory and technical documents approved by the USSR Ministry of Health.

ChangeN 1 , approved by the Deputy Minister of Chemical and Petroleum Engineering on January 4, 1987, paragraph 3.9 of this OST has been amended to come into force on July 1, 1987.

3.9 .When degreasing with group 2 solvents (see and), fire safety must be ensured in accordance with GOST 12.1.004, SNIP and PUE.

3.10. The amount of freon 113 and freon 114B2 poured into degreased systems or auxiliary equipment should not exceed 0.3 kg per 1 m 3 of the room.

Change No. 1, approved by the Deputy Minister of Chemical and Petroleum Engineering on January 4, 1987, changes were made to clause 3.11 of this OST, which will come into force on July 1, 1987.

3.11. Before entering the room where degreasing is carried out, warning signs should be posted: "Solvent - poison", "No entry to strangers", "No smoking" and other safety signs, in accordance with GOST 12.4.026.

3.12. Distillation residues of solvents are subject to delivery to the enterprises of the Ministry of Chemical Industry or must be regenerated by consumers.

3.13. Workers engaged in degreasing work must be provided with protective equipment in accordance with GOST 12.4.011.

Change No. 1, approved by the Deputy Minister of Chemical and Petroleum Engineering on January 4, 1987, changes were made to paragraph 3.14 of this OST, which will enter into force on July 1, 1987.

3.14. When using ultrasonic cleaning, the requirements of GOST 12.1.001 and "Sanitary norms and rules for working on industrial ultrasonic installations" dated May 24, 1977 must be met.

3.15. When working with electrical appliances, you must comply with the requirementsGOST12.1.019.

3.16. The issues of draining the remains of aqueous cleaning solutions and disposal should be resolved by the design organization in accordance with the current guidance materials "Rules for the protection of surface water from sewage pollution" N1166.

4. General technological requirements

4.1. The degreasing process consists of the following operations:

Preparation for degreasing;

Degreasing;

Removal of residues of used degreasers.

4.2. Preparation for degreasing.

4.2.1. Before degreasing, the equipment must have a temperature between 12°C and 30°C.

If it is technically necessary to carry out degreasing at lower or higher temperatures, in each specific case, a special technological process must be developed.

Safety valves and instrumentation must be removed from the equipment and degreased separately.

4.2.2. Products coated with preservation lubricants must be depreserved in accordance with OST 26-04-2138 before degreasing with aqueous detergent solutions or solvents.

4.2.3. Before degreasing with solvents, in order to avoid corrosion, the products must be thoroughly dried.

4.3. Degreasing.

When circulating the cleaning solution, the following conditions must be met:

The duration of circulation is not less than 30 minutes, but not more than 2 hours;

The amount of the circulating aqueous washing solution is not less than the volume of the products, while washing the entire degreased surface with the solution must be guaranteed;

Degreasing should be done twice with intermediate and final flushing with hot water.

6.4. Degreasing of gasifier tanks is carried out by condensation of solvent vapors in accordance with the standard.

Degreasing of evaporators is carried out by the solvent circulation method.

Degreasing ends when the content of fatty contaminants in the drained condensate is not more than 20 mg/dm 3 .

6.5. Spindle groups of fittings are degreased by wiping with aqueous detergent solutions.

6.6. Degreasing of spindle groups of fittings with solvents of group 1 of the standard is not allowed.

Degreasing of evaporators with aqueous cleaning solutions is not allowed.

6.7. After degreasing, the gasifier is purged until the solvent residues are completely removed. Completeness of solvent removal should be verified by analysis.

Purge of the medical oxygen gasifier should be carried out until the complete absence of the vapor solvent in the gas during the control purge (no more than 2 mg/m3).

6.8. When oxygen is used in the gasifier in accordance with GOST 6331, degreasing of the tank, valve cabinet and pipelines is not performed.

7. Degreasing oxygen compressors

7.1. Small parts are degreased according to the standard.

7.2. Degreasing of valves with solvents should be carried out only in disassembled form.

7.3. Large parts, for example, a cylinder, a cover, rods, pistons, etc., are degreased in baths with an aqueous washing solution or solvent, or by wiping the surfaces with cloths moistened with low-toxic solvents (see standard) or hot water washing solution.

7.4. Shell-and-tube refrigerators, dehumidifiers, receivers and other containers are filled with 1/3-1/2 volume of solvent, after which they are turned over. If the parts are degreased after depreservation, it is necessary to wash the parts with a solvent two or three times. It is recommended to degrease these devices by condensing solvent vapors or washing them with a hot washing solution (see standard).

7.5. Serpentine refrigerators are degreased with a solvent or hot cleaning solution by circulation or filling (see standard).

7.6. After degreasing, the compressor must be run in air or nitrogen for 2 hours.

7.7. Degreasing of oxygen turbochargers is carried out in accordance with RTM 26-12-43.

8. Degreasing pipelines and hoses

8.1. The need for degreasing assembly pipelines with a pressure of more than 4.0 MPa (40 kgf / cm 2) is determined by the technical documentation, it is recommended to make a decision on degreasing after checking the open ends of the pipeline, in accordance with OST 26-04-2574.

8.2. Liquid oxygen pipelines are checked for the presence of fatty contaminants at least once a year, in the case when oxygen with a content of fatty contaminants higher than the requirements of GOST 6331 is transported through it.

Control checks for the presence of fatty contaminants are subject to areas with the lowest flow rate, and with a uniform flow - inlet areas. Control is carried out according to section 5 of the standard.

In case of exceeding the standard OST 26-04-1362, the entire pipeline is subjected to degreasing.

8.3. When degreasing by immersion in baths, the pipes are placed in special baths filled with aqueous cleaning solutions or solvents, and kept in accordance with the standard.

8.4. For circulation degreasing, the pipelines are connected to a special system equipped with a pump, through which aqueous cleaning solutions or solvents are pumped (see standard).

8.5. Degreasing the inner surface of the pipes by filling is carried out as follows: technological plugs are installed on the ends of the pipes. A solvent is poured through the appropriate fitting in the plug, after which the fitting is closed, and the pipes or hoses are laid horizontally. The pipes should be in a horizontal position for 10-20 minutes, during which time they should be turned 3-4 times in order to wash the entire inner surface with a solvent. Pipes filled with solvent can also be moved in special rocking chairs or rotary mechanisms.

8.6. The sections of the installed pipeline are degreased by circulating a solvent and an aqueous cleaning solution.

8.7. The approximate solvent consumption required for a single degreasing of the inner surface of one linear meter of pipe is calculated by the formula:

(2)

where Q- solvent consumption, dm 3 /m;

D- internal diameter of the pipe, cm.

Solvent consumption for single pipe degreasing is given in Table. 2.

table 2

Solvent consumption for one-time pipe degreasing

Continuation of the table. 2

Continuation of the table. 2

8.8. Small sections of pipelines can be degreased by wiping or by jetting an aqueous cleaning solution using special tools.

8.9. The outer surfaces of the ends for a length of 0.5 m during installation are wiped with napkins soaked in a solvent or an aqueous washing solution and dried in the open air.

8.10. All parts intended for connecting hoses to the tank must be degreased by wiping if they were contaminated during storage.

8.11. Hoses of tanks of medical oxygen are degreased together with a vessel.

8.12. Fat-free sections of pipelines to be stored or transported must be plugged and sealed.

8.13. Sections of pipelines subjected to chemical passivation or other types of chemical surface treatment before assembly may not be degreased if the requirements of the standard are met.

8.14. Sections of pipelines and hoses, degreased during manufacture, received for installation with plugs and having the appropriate marks in the passport, are not degreased.

8.15. Assembly pipelines are not subjected to degreasing, with a pressure of up to 4.0 MPa (40 kgf / cm 2), if the pipeline sections before assembly or the assembly pipelines were cleaned from scale, slag, etc. by pickling, sandblasting and shot blasting.

8.16. The main pipelines and intershop pipelines of oxygen, with a pressure of up to 1.6 MPa (16 kgf / cm 2), as an assembly are not degreased if, before connecting the individual pipes, during a visual inspection, the absence of stains of fatty contamination on the surface of the pipelines is confirmed, for which an act must be drawn up.

9. Degreasing fittings and appliances

9.1. Degreasing is carried out after manufacture, before installation and after repair, i.e. in cases where contamination of the fittings was possible.

9.2. The fittings are degreased in disassembled form with aqueous detergent solutions. It is allowed to pre-wipe with a cloth soaked in white spirit or kerosene. In this case, special attention should be paid to fire safety measures.

9.3. In case of technical necessity, it is allowed to degrease the fittings without dismantling. To determine the possibility of degreasing purchased fittings without dismantling, it is recommended to degrease it, dry it, and then disassemble and check for residual content of fatty contaminants. If the residual content will meet the standards, according to. standard, further fittings can be degreased without dismantling.

Particular attention should be paid to the stuffing box and its packing.

9.4. When degreasing fittings without dismantling, the compatibility of all materials from which the fittings are made, especially seals, with the detergents used should be taken into account.

9.5. The armature is not subject to degreasing before its installation, if the degreasing was carried out at the factory (which must be confirmed by the accompanying documents or appropriate branding) and the packaging is not broken.

9.6. Gaskets made of rubber, paronite, fibers, fluoroplastic gland rings, parts made of fiberglass, polycarbonate and textolite are degreased by wiping with aqueous detergent solutions and rinsed with water.

9.7. Asbestos used for stuffing box packing of fittings is degreased by calcination at a temperature of 300°C for 2-3 minutes.

9.8. Degreasing of devices for measuring flow and pressure is carried out according to OST 26-04-2158.

Annex 3

Mandatory

Solvent Requirements

Input control

Name of indicator	Norm	Control method
1. Appearance	Colorless, clear liquid	Determined visually
	It must be transparent and not contain foreign impurities suspended and settled on the bottom of the cylinder.	Pour the solvent into a glass cylinder with a diameter of 40-50 mm
3. Reaction of the environment	The water layer should not turn pink	The solvent in the amount of 15 cm 3 is placed in a separating funnel, 40 cm 3 of distilled water are added and shaken for 3-5 minutes; after settling, the aqueous layer is drained and methyl orange 0.1% aqueous solution is added to it
	Section 2 of the standard, tab. 2	According to OST 2 6-04-2574

Appendix 4

Mandatory

Preparation of baths with aqueous cleaning solutions, their control and adjustment

1. Composition of baths

1.1. The amount of each component provided by the recipe is calculated based on the composition and its useful capacity. The components of the solution, depending on local conditions, can be dissolved individually in auxiliary vessels or directly in the bath in which the degreasing is performed. Dissolution is carried out by heating to a temperature of 60-70°C with vigorous stirring of the solutions with mechanical agitators or air bubbling.

1.2. After compiling the bath, the total alkalinity of the freshly prepared composition is determined according to the procedure given below.

2. Control and adjustment of baths

2.1. General requirements

2.1.1. Control analyzes of the composition of aqueous detergent solutions in degreasing baths are carried out at least 2 times a week by determining the total alkalinity of the solution. Vann adjustments are made according to the results of control analyses. The general change of the water washing solution with regular loading of the bath is carried out once a week.

2.1.2. During the operation of the baths, do not allow the accumulation of contaminants on the surface of the solutions. Regularly remove fatty contaminants from the surface using special devices (a perforated spoon or mesh) or special grease traps.

2.1.3. Before taking a sample of the solution for control analysis, it is necessary to bring the solution to the desired level and mix.

2.2. Determination of the total alkalinity of a solution

Amendment No. 1, approved by the Deputy Minister of Chemical and Petroleum Engineering on January 4, 1987, amended subparagraph 2.241 of this Appendix, which will enter into force on July 1, 1987.

Amendment No. 2 to subparagraph 2.2.1 of this appendix amended

2.2.1. Used reagents, solutions and utensils:

Hydrochloric acid, according to GOST 3118, 0.1 m solution;

Indicator methylorange according to TU 6-09-5171, 0.1%;

distilled water, according toGOST 6709;

Conical flasks, according to GOST 25336, with a capacity of 250 cm 3;

Volumetric pipettes, according to GOST 1770, with a capacity of 100 cm 3;

Measuring burette, according to GOST 1770, with a capacity of 25 cm 3.

2.2.2. To carry out the determination, 5 cm 3 of a cooled aqueous washing solution is placed in a 250 cm 3 conical flask, diluted with water to 100 cm 3, 2-3 drops of methyl orange solution are added and titrated with 0.1 N, HCl until the yellow color changes to pale pink.

2.2.3. The total alkalinity of the solution in terms of NaOH in g / dm 3 is calculated by the formula:

where q-amount of 0.1 n solution HCl, spent on titration, cm 3;

0.004 - solution titer HCl,G;

To- correction to the titer of 0.1 N solution HCl;

m- the amount of solution taken for analysis, cm 3.

2.3. Bath adjustments

2.3.1. According to the results of control analyzes, the baths are adjusted if the total alkalinity of the solution decreases by more than 20%.

2.3.2. When adjusted, all components of the solution are added to the bath. The calculation of the added amount is carried out according to the main component, which determines the total alkalinity of the solution. For example, according to the control analysis of the composition bath:

NaOH - 10 g; Na 3 PO 4 -15g; Na 2 SiO 3 -2 g; OP-7 - 2-3 g; H 2 O - 1 dm 3 total alkalinity decreased by 35%. When adjusting, it is necessary to add to the bath based on 1 dm 3:

NaOH - 3.5 g; Na 2 SiO 3 - 0.7 g; Na 3 PO 4 - 5.2 g; OP-7 - 0.7-1 g.

Amendment No. 2 amended this List

Amendment No. 1, approved by the Deputy Minister of Chemical and Petroleum Engineering on January 4, 1987, amended this List, effective from July 1, 1987.

List of reference normative and technical documents (NTD)

Designation	Name	Sheet (page)
GOST 9.010-80	ESZKS. Compressed air for spraying paints and varnishes. Technical requirements. Rules and methods of control
GOST 9.305-84	E C 3 COP. Metallic and non-metallic, inorganic coatings. Operations of technological processes for obtaining a coating
GOST 12.1.001-83	SSBT. Ultrasound. General safety requirements.
GOST 12.1.004-85	SSBT. Fire safety. General requirements.
GOST 12.1.014-84	SSBT. Work area air. Method for measuring the concentration of harmful substances with indicator tubes.
GOST 12.1.016-79	SSBT. Work area air. Requirements for methods for measuring concentrations of harmful substances.
GOST 12.1.019-79	SSBT. Electrical safety. General requirements.
GOST 12.2.052-81	SSBT. Equipment operating with gaseous oxygen. General safety requirements	2, 3, 20
GOST 12.3.008-75	SSBT. Production of metallic and non-metallic inorganic coatings. General safety requirements.
GOST 12.4.011-89	SSBT. Means of protection for workers. Classification.
GOST 12.4.026-81	SSBT. Signal colors and safety signs
GOST 17.2.3.02 -78	Protection of Nature. Atmosphere. Rules for Establishing Permissible Emissions of Harmful Substances by Industrial Enterprises
GOST 201-76	Trisodium phosphate. Specifications.
GOST 443-76	Nephrases S2-80/120 and SZ-80/120. Specifications.
GOST 1770-74E	Ware measured laboratory glass. Cylinders, beakers, flasks. Specifications.	31, 34
GOST 22 63-79	Sodium caustic technical. Specifications.
GOST 2874-82	Drinking water. Hygienic requirements for quality control.
GOST 3118-77	Hydrochloric acid. Specifications.
GOST 3134-78	Gasoline solvent for the paint and varnish industry. Specifications.
GOST 4328-77	Reagents. sodium hydroxide. Specifications.
GOST 4753-68	Kerosene lighting. Specifications.
GOST 5583-78	Oxygen gaseous technical and medical. Specifications.
GOST 6331-78	Oxygen liquid technical and medical. Specifications.	20, 26
GOST 6709-72	Distilled water.
GOST 8505-80	Nefras-S 50/170. Specifications.
GOST 9293-74	Nitrogen gaseous and liquid. Specifications.
GOST 9337-79	Sodium phosphate 12-water. Specifications.	7, 8
GOST 9976-83	Trichlorethylene technical. Specifications.	4, 5
GOST 2533 6-82	Ware and laboratory glassware. Type, main parameters and dimensions.
GOST 10652-73	Ethylenediamine disodium salt - N, N, N¢ , N ¢ tetraacetic acid, 2-aqueous (Trilon-B).
GOST 13078-81	Liquid sodium glass. Specifications.
GOST 15899-79	Freon 114V2. Specifications.
GOST 19906-74	Sodium nitrite technical. Specifications.	8, 11
OST 26-04-13 62-75		2, 20, 24, 26
OST 26-04-2138-81	Temporary anticorrosive protection of products.
OST 26-04-2158-78	SSBT. Means for measuring flow and pressure. Safety requirements for use in an oxygen gas environment.
OST 26-04-2574-80	Gases, cryogenic products, water. Methods for determining the content of mineral oils.	18, 24, 26, 30
OST 26-04-2578-80	Gases, cryoproducts. Chromatographic method for the determination of impurities in organochlorine solvents.	12, 16
OST 26-04-2600-83	The equipment is cryogenic. General specifications.
RTM 26-12-43-81	Degreasing of centrifugal oxygen compressors.
TU 6-01-927-76	Trichlorethylene stabilizer (STAT-1) .
TU 6-02-640-80	Nonionic drug synthamide-5.
TU 6-09-1181-76	Universal indicator paper for determining pH 1-10 and 7-14.
TU 6-09-5171-84	Indicator methyl orange (para-dimethylanino-azobenzenesulfonic acid sodium)
TU 6-01-956-86	Tetrachlorethylene (perchlorethylene)	4, 5
TU 6-14-577-88	Detergent Sintanol DS-10
TU 6-15-978-76	Synthetic detergent HC-8.
TU 6-18-5-77	Preparation KM-2.
TU 38.103 62-87	Surfactant NEONOL AF9.12
TU 38-10761-75	Synthetic detergent Vimol.
TU 8-10960-81	Detergent technical Vertolin -74.
TU 38-107113-78	Detergent technical TNS-31.
TU 38.50724-84	Surfactant NEONOL AF9.6
TU 6-1816-82	Degreaser of aluminum alloys OSA.	9, 10
TU 84-348-73	Washing preparation ML-72.

The interaction of compressed gaseous oxygen with organic substances (fats, lubricants) leads to their self-ignition and explosion. Therefore, it is so important when working with the appropriate equipment to exclude such contact for all devices. One of the obligatory measures in this case is the degreasing of oxygen manometers that perform a control and measuring function. It is carried out after each state verification of the device.

How to determine the presence of organic oils inside the pressure gauge? To do this, hot water must be injected into the inlet of the fitting using a syringe. After vigorous shaking, pour it into a test tube with ordinary clean water or onto a white paper sheet. The presence of oil will be indicated by an iridescent film on the surface of the liquid or greasy spots on paper.

Solvent degreasing

If there is an oil fraction inside the device, it is necessary to thoroughly degrease the pressure gauge. To do this, chlorine-containing solvents (trichlorethylene, perchlorethylene, freon 113) are injected into the cavity of its tubular spring, which must be inside the measuring device for at least 20 minutes. After exposure, they are removed by evacuation or by free flow into the prepared vessel.

The quality of solvent degreasing is controlled by checking its last portion. The spent liquid is poured onto an absorbent paper napkin and the presence of oil inclusions is determined by fluorescence of its surface in ultraviolet light. Compared to water wetting, they have a different luminescence intensity.

Degreasing the pressure gauge with chlorine-containing solvents provides no more than 20 mg / sq.m. residual oil content.

As for checking the oil content on the outer surface of the pressure gauge, it is carried out in two ways: with ultraviolet illuminators and with a special thin glass fiber cloth.

In the latter case, the presence of fatty contaminants is checked with a luminescent device or the so-called quantitative method. With it, the used napkin is washed in 100 cm 3 of the solvent. After that, 10 cm 3 of this solution is poured into the cuvette of a luminescent device, where the oil content is determined.

Control over the degreasing of oxygen manometers is based on measurements of the concentration of fatty contaminants in the spent solvent. The figures obtained should not exceed the normative values, depending on the pressure of the measured oxygen-containing medium.

Change No. 2 to this OST has been amended

Industry Standard

OST 26-04-312-83

Equipment degreasing methods. General requirements for technological processes

(put into effect by letter of the Technical Department of Minkhimmash dated November 29, 1983 N 11-10-4 / 1685)

The validity period is set from January 1, 1985. Instead of OST 26-04-312-71 This standard applies to cryogenic, cryogenic-vacuum equipment and equipment operating with oxygen, including medical, nitrogen and other air separation products, and establishes general technological requirements for methods for removing fatty contaminants from the surface of products (degreasing). The standard does not establish requirements for the processes of depreservation of products. Explanations of the terms used in this standard are given in reference annex 1.

1. General provisions 2. Technical requirements 3. Safety requirements 4. General technological requirements 5. Quality control of degreasing Appendix 1 Explanation of terms Appendix 2 Features of degreasing various types of equipment and transport tanks 4. Degreasing of liquid oxygen pumps 5. Degreasing of gasification plants 6. Degreasing of cryogenic cold gasifiers of the GKH type 7. Degreasing of oxygen compressors 8. Degreasing of pipelines and hoses 9. Degreasing of fittings and devices washing solutions, their control and adjustment 1. Preparation of baths 2. Control and adjustment of baths

1. General Provisions

1.1. Degreasing of equipment should be carried out in case of exceeding the norms for the content of fatty contaminants on the surface, established by regulatory and technical documents, technical documentation (drawings, specifications and operational documentation), during manufacture, installation, repair and operation. The standards for equipment operating with gaseous oxygen are established in accordance with GOST 12.2.052, for equipment operating with liquid oxygen - according to OST 26-04-1362, for cryogenic vacuum equipment - according to OST 26-04-2600. The method and means of degreasing are indicated in the technological documentation. The operational documentation indicates the method, means and frequency of degreasing or the criteria that determine the need for degreasing Depending on the design features of the product, it is allowed to indicate the degreasing method in the technical documentation (drawings, specifications), if this method is the only one that guarantees the required quality of degreasing, or limit the use of individual methods . 1.1.1. Excluded since July 1, 1987 1.2. The procedure for degreasing equipment during manufacture must be established by instructions and technological processes developed at the manufacturer in accordance with the requirements of this standard. When carrying out installation or repair work, the procedure and technological process of degreasing, developed in accordance with the requirements of this standard, must be determined by the organization conducting the installation or repair work, degreasing during operation is carried out in accordance with the operational documentation. Change No. 1 , approved by the Deputy Minister of Chemical and Petroleum Engineering on January 4, 1987, paragraph 1.3 of this OST has been amended to come into force on July 1, 1987. 1.3. Degreasing of individual parts before assembly or products after assembly at the factory and during installation may not be carried out if, during the manufacturing process, the parts from which the product is assembled were degreased or underwent chemical or galvanic treatment in accordance with GOST 9.305 (clarification, passivation, galvanizing, etc.). .p.), and surface contamination was excluded during storage and assembly. In case of contact with fatty contaminants on parts with galvanized coatings, it is allowed to degrease them by wiping with aqueous detergent solutions at a temperature not exceeding 40°C. Please note that this may damage the appearance of the coating. 1.4. Degreasing during installation is not subject to equipment that meets the requirements of technical documentation for the content of fatty contaminants on the surface, has confirmation in the passport and arrived at the installation site with intact plugs and in a whole package. 1.5. Features of degreasing of various types of equipment are given in the recommended Appendix 2. 1.6. Compliance of the content of fatty contaminants with the established standards is confirmed by a mark in the control route chart, in the technological passport of the product or in other technical documentation. On the basis of these documents, marks are entered in the product passport, for example: "The content of fatty contaminants does not exceed the standards established by GOST 12.2.052" * or "fat-free." 1.7. The preparation and conduct of all degreasing work should be supervised by a responsible person appointed by a written order of the administration, who should be fully responsible for compliance with the degreasing technology, timely technical control and safety of the work.

2. Technical requirements

2.1. Material Requirements

2.1.1. Solvents or aqueous cleaning solutions should be used to degrease the equipment. The need to use solvents or aqueous cleaning solutions should be indicated in the technological documentation.

2.2. Solvents

2.2.1. Solvents are divided into two groups: Group 1 - fireproof, used for degreasing assembled products both at manufacturing plants and during equipment operation. Group 2 - fire and explosion hazardous, used for degreasing products by wiping, subject to the subsequent complete removal of solvents from the internal cavities of degreased products. When using solvents of group 2, the conditions ensuring fire and explosion safety, in accordance with clause 3.9, must be observed. The used solvents of groups 1 and 2, used at a temperature of 10-20 ° C, depending on the detergent and physico-chemical properties, are given in table. one. Change No. 1, approved by the Deputy Minister of Chemical and Petroleum Engineering on January 4, 1987, changes were made to subparagraph 2.2.2 of this OST, which will come into force on July 1, 1987. 2.2.2. When degreasing materials other than those listed in Table. 1, tests should be carried out for corrosion compatibility with solvents and for residual greasy contaminants.

Scope of solvents

Table 1

Name of solvents

Residual content of fatty contaminants, mg/m 2 , no more

Application area

Group 1

Freon 113 GOST 23844

Freon 114V2 GOST 15899

Trichlorethylene GOST 9976

For steel, cast iron, copper and alloys based on iron, copper and nickel

Tetrachlorethylene TU 6-01-956

Trichlorethylene GOST 9976 with stabilizer STAT-1-1% TU 6-01-927

For products made of steel, cast iron, copper, aluminum and alloys based on iron, copper, nickel, aluminum

Tetrachlorethylene TU 6-01-956 with stabilizer STAT-1-1% TU 6-01-927

Group 2

Nephrases S2-80/120 and SZ-80/120 GOST 443

For products made of any metals and alloys

Nefras-S 50/170 GOST 8505 (distilled)

Gasoline solvent for the paint and varnish industry (white spirit) GOST 3134

For preliminary removal of fatty contamination of products from any metals and alloys

2.2.3. The quality of the solvent must fully meet the requirements of normative and technical documents for the solvent and is confirmed by the certificate of the manufacturer. Solvents supplied for degreasing must be checked before use according to the indicators specified in mandatory Appendix 3. 2.2.4. Degreasing with a solvent is carried out 1-2 times depending on the shape of the parts and the required quality of degreasing. When carrying out double degreasing, the residual content of fatty contaminants can be taken equal to the upper limit given in table. 1 without control. 2.2.5. For primary degreasing, solvents containing fatty contaminants should be used in accordance with Table. 2, at the same time, complete draining of the solvent from the product must be ensured (the residual solvent layer is not more than 1 mm). table 2

Permissible content of fatty contaminants

2.2.6. When re-degreasing, solvents with a content of fatty contaminants of not more than 50 mg/dm 3 should be used. In the following, solvents that meet the above requirements are referred to as pure. 2.2.7. The use of stabilizer CTAT-1 is mandatory when degreasing products made of aluminum and its alloys, and preferably when degreasing other metals.

2.3. Aqueous cleaning solutions

2.3.1. Fireproof non-toxic aqueous cleaning solutions are used for degreasing assembled and disassembled products, the design of which provides the possibility of completely draining the solution and removing its residues by washing with water, both at manufacturing plants and during installation and operation of equipment. Change No. 1, approved by the Deputy Minister of Chemical and Petroleum Engineering on January 4, 1987, changes were made to subparagraph 2.3.2 of this OST, which come into force on July 1, 1987. 2.3.2. The compositions of aqueous cleaning solutions, technological modes and scope with indication of materials are given in Table. 3. Instructions for the preparation of baths with aqueous solutions, their control and adjustment are given in the mandatory Appendix 4. Table 3

Compositions of aqueous cleaning solutions and degreasing regimes

Compositions of aqueous cleaning solutions

Degreasing modes

Residual content of fatty contaminants, mg/m 2

Application area

components of aqueous cleaning solutions and detergents

quantity, g / dm 3

temperature °C

degreasing ratio

Composition 1

twice

For steel, cast iron, copper and alloys based on iron, copper and nickel

Sodium phosphate, (trisodium phosphate),

Detergent*

Sodium hydroxide (caustic soda)

Liquid sodium glass

Detergent*

Composition 2

twice

For steel, cast iron, copper, aluminum and alloys based on iron, copper, nickel, aluminum

Liquid sodium glass

Detergent*

For products made of steel, cast iron, copper and alloys based on iron, copper and nickel, with increased requirements for the absence of deposits on their surface

Sodium nitrite technical

Sodium phosphate (trisodium phosphate)

Detergent*

Detergent ML-72

Synthetic detergent MS-8

Detergent KM-2

For steel, cast iron, copper, aluminum and alloys based on iron, copper, nickel, aluminum

twice

For steel, cast iron, aluminum and alloys based on iron, nickel, aluminum

Detergent technical synthetic VIMOL

For products made of copper and its alloys

Detergent technical TMS-31

For products made of steel, cast iron and alloys based on iron, nickel, aluminum

Detergent technical Vertolin-74

once

Detergent technical Vertolin-74

twice

For steel, cast iron, copper and alloys based on iron, copper and nickel

once

For products made of aluminum and its alloys

Aluminum alloy degreaser (OSA)

twice

For steel, cast iron, copper and alloys based on iron, copper and nickel

Detergents for household chemicals**

______________________________ * One of the following substances is used: Surfactant Neonol AF9.6. TU 38.50724 (20g / l) or Neonol AF9.12 TU 38.10362 (5g / l), sintanol DS-10 according to TU 6-14-577 - 5 g / dm 3; non-ionic drug synthamide 5 according to TU 6-02-640 - 5 g / dm 3. ** When using solutions with detergents for household chemicals, it is mandatory to inspect fat-free products after washing and drying. If dry residues of cleaning solutions are found, they must be removed. 2.3.3. The components of aqueous cleaning solutions must comply with the requirements of the regulatory and technical documents indicated in Table. 3. 2.3.4. For the preparation of aqueous cleaning solutions, drinking water is used in accordance with GOST 2874. The use of water from the circulating water supply system is not allowed. 2.3.5. When degreasing products from other materials, except for those indicated in Table. 3, they should be tested for corrosion compatibility with aqueous cleaning solutions and for the cleanliness of degreasing achieved. 2.3.6. For washing products made of ferrous metals, after degreasing with aqueous detergent solutions, it is recommended to use water with the addition of a corrosion inhibitor - technical sodium nitrite according to GOST 19906 in an amount of 2 g / dm 3 of water. 2.3.7. For drying products and removing vapors, air should be used in accordance with GOST 9.010 or gaseous nitrogen in accordance with GOST 9293. To remove vapors from solvents of group 2, table. 1 only nitrogen is allowed.

3. Security requirements

3.1. Safety requirements during the degreasing process must comply with GOST 12.3.008. 3.2. When working with components of aqueous cleaning solutions and solvents, you should comply with the safety requirements set forth in the regulatory and technical documents for the substances used, given in Table. 1 and 3. 3.3. When degreasing cryogenic vessels, if the presence of a person in them is required, the requirements of the "Temporary standard instruction for the organization of safe gas hazardous work at enterprises of the USSR Ministry of Chemical Industry", approved by the USSR State Gortekhnazor and the USSR MHP, must be observed. Before carrying out degreasing work on cryogenic vessels that were in operation, they must be warmed up to temperatures in the range of 12-30 ° C and ventilated. Work should be carried out only when the oxygen content in the air inside the vessels is in the range from 19 to 23%. In the organization conducting degreasing, the instructions for carrying out these works must be approved in accordance with the established procedure. 3.4. Degreasing of individual parts by immersing them in baths with solvents should be carried out in apparatus with a closed or semi-closed degreasing cycle, equipped with local ventilation and excluding the ingress of solvent vapors into the air of industrial premises. At the same time, it is necessary to create continuity in the process of degreasing, drying and unloading parts. Drainage of the solvent from the equipment and baths must be carried out in closed vessels through pipelines. 3.5. When degreasing equipment with group 1 solvents (see clause 2.2.1.), it is necessary to ensure the tightness of the equipment in which degreasing is performed. 3.6. Air emissions after drying and blowing must comply with GOST 17.2.3.02. 3.7. The ventilation of the premises must ensure the fulfillment of the requirements for the air of the working area in accordance with GOST 12.1.005. Table 4

Maximum allowable concentrations of solvents in the air

Name of solvents

The value of the maximum permissible concentration, mg / m 3

Hazard Class

Trichlorethylene

Tetrachlorethylene

Freon 113

Freon 114V2

Gasoline-solvent for the rubber industry (in terms of C)

Nefras-S 50/170

White spirit (in terms of C)

Amendment No. 1, approved by the Deputy Minister of Chemical and Petroleum Engineering on January 4, 1987, amended paragraph 3.8 of this OST, which shall enter into force on July 1, 1987. 3.8. Analysis of air samples for the content of harmful substances should be carried out according to the methods developed in accordance with GOST 12.1.014 and GOST 12.1.016, guidelines and other regulatory and technical documents approved by the USSR Ministry of Health. Change No. 1 , approved by the Deputy Minister of Chemical and Petroleum Engineering on January 4, 1987, paragraph 3.9 of this OST has been amended to come into force on July 1, 1987. 3.9. When degreasing with solvents of group 2 (see clause 2.2.1. and clause 4.3.7.), fire safety must be ensured in accordance with GOST 12.1.004, SNIP and PUE. 3.10. The amount of freon 113 and freon 114B2 poured into degreased systems or auxiliary equipment should not exceed 0.3 kg per 1 m 3 of the room. Amendment No. 1, approved by the Deputy Minister of Chemical and Petroleum Engineering on January 4, 1987, amended paragraph 3.11 of this OST, which shall enter into force on July 1, 1987. 3.11. Before entering the room where degreasing is carried out, warning signs should be posted: "Solvent - poison", "No entry to strangers", "No smoking" and other safety signs, in accordance with GOST 12.4.026. 3.12. Distillation residues of solvents are subject to delivery to the enterprises of the Ministry of Chemical Industry or must be subjected to regeneration at consumers. 3.13. Workers engaged in degreasing work must be provided with protective equipment in accordance with GOST 12.4.011. Amendment No. 1, approved by the Deputy Minister of Chemical and Petroleum Engineering on January 4, 1987, amended paragraph 3.14 of this OST, which shall enter into force on July 1, 1987. 3.14. When using ultrasonic cleaning, the requirements of GOST 12.1.001 and "Sanitary norms and rules for working on industrial ultrasonic installations" dated May 24, 1977 should be met. 3.15. When working with electrical appliances, the requirements of GOST 12.1.019 must be observed. 3.16. The issues of draining the residues of aqueous cleaning solutions and disposal should be resolved by the design organization in accordance with the current guidance materials "Rules for the protection of surface water from sewage pollution" N 1166.

4. General technological requirements

4.1. The degreasing process consists of the following operations: - preparation for degreasing; - degreasing; - removal of residues of used degreasing agents. 4.2. Preparation for degreasing. 4.2.1. Before degreasing, the equipment must have a temperature of 12°C to 30°C. If it is technically necessary to carry out degreasing at lower or higher temperatures, a special technological process must be developed in each specific case. Safety valves and instrumentation must be removed from the equipment and degreased separately. 4.2.2. Items coated with conservation lubricants must be depreserved before degreasing with aqueous detergent solutions or solvents in accordance with OST 26-04-2138. 4.2.3. Before degreasing with solvents, in order to avoid corrosion, the products must be thoroughly dried. 4.3. Degreasing. 4.3.1. Degreasing with solvents and aqueous cleaning solutions is carried out by the following methods: - filling the internal cavities of products; - immersion in baths; - circulation of solvents or cleaning solutions in washed products; - condensation of solvent vapors in washed products; - jet cleaning; - rubbing; - ultrasonic cleaning. 4.3.2. Choice of degreasing method according to clause 4.3.1. is produced depending on the size of the degreased products and the available technical means of degreasing. It is preferable to degrease the products before assembly, taking into account the requirements of clause 1.3. 4.3.3. Degreasing by filling the internal cavities of products or immersion in baths is used for individual parts or assembly units, as well as for small products, and is carried out using solvents and aqueous cleaning solutions. The solvent must be in degreased products for at least 30 minutes. The stay of the solvent in the products should not exceed 1.5 hours. Degreasing with aqueous cleaning solutions is carried out twice with intermediate and final washing with hot water (60-80 ° C), the temperature of the solution is indicated in Table. 3. In each bath with aqueous cleaning solutions, the products should be 30 minutes, in baths with hot water - 15 minutes. Degreasing time composition N 2, table. 3 - 15 minutes. Staying products in contact with aqueous cleaning solutions should not exceed 2 hours. 4.3.4. The method of circulation of solvents or aqueous cleaning solutions is used for degreasing pipelines, hoses, as well as assembled products, the design of which makes it possible to wash all surfaces to be degreased with a circulating solution (tubular heat exchangers, etc.). ). Degreasing by the circulation method is carried out in the product with solvents or cleaning solutions, the circulation rate is from 0.5 to 1.0 m/s. When circulating the solvent, the following conditions must be observed: - circulation time of at least 20 minutes. and no more than 1.5 hours; - the amount of circulating solvent - not less than the volume of the product, while washing with the solvent of the entire degreased surface must be guaranteed; - the need for repeated degreasing is determined by the results of the analysis of the solvent drained from the product (see clause 5.3.). When circulating the washing solution, the following conditions must be observed: - the duration of circulation is at least 30 minutes, but not more than 2 hours; - the amount of circulating aqueous cleaning solution is not less than the volume of products, while washing the entire degreased surface with the solution must be guaranteed; - degreasing should be done twice with intermediate and final washing with hot water. 4.3.5. The method of degreasing by condensation of solvent vapors is used for degreasing cryogenic vessels, pipelines, hoses and is carried out by supplying solvent vapor heated to the boiling point to the degreased cavities, and then condensing the vapor on the surface to be degreased. The condensate is drained from the equipment. The solvent poured into the evaporator is not subject to requirements for the content of fatty contaminants in accordance with paragraphs. 2.2.5. and 2.2.6. The solvent consumption for a single degreasing is 5-10 dm 3 per 1 m 2 of the degreased surface. Degreasing ends when the content of fatty contaminants in the condensate drained from the product is not more than 20 mg / dm 3, however, in any case, the solvent consumption must be at least 5 dm 3 /m 2. 4.3.6. The jet cleaning method is used to degrease individual products or the internal surfaces of vessels and is carried out by supplying a solvent or aqueous washing solution to the surface to be degreased with a jet under high pressure through special nozzles that provide washing of the entire degreased surface. The amount of solvent or aqueous cleaning solution supplied to the surface to be degreased must be at least: for solvents 25 dm 3 /m 2, for cleaning solutions 50 dm 3 /m 2. When degreasing with a jet method, intermediate washing with hot water is not necessary. 4.3.7. The wipe method is used in the absence of special equipment or more effective methods of degreasing. This method is used for degreasing large-sized products, cryogenic vessels, if they have hatches, and for small-sized products, subject to free access to degreased cavities and is performed by repeatedly wiping the degreased surfaces with napkins with hemmed edges moistened with a hot aqueous washing solution at a temperature of 40-45 °C. Subject to compliance with safety requirements, it is allowed to use freon 113 and freon 114B2 or group 2 solvents for wiping small items. 4.3.8. The ultrasonic cleaning method should be used for degreasing products of complex configuration. Degreasing is carried out with group 1 solvents or hot aqueous washing solutions (see Tables 1, 3) in special ultrasonic baths. The duration of degreasing is 10-15 minutes. After degreasing with aqueous detergent solutions, the products are washed with hot water. 4.4. Removal of residues of used degreasers. 4.4.1. Removal of solvent residues from products after their degreasing is carried out by blowing with compressed air or nitrogen, according to clause 2.3.7. For group 2 solvents, only nitrogen is used. The gas used for purge must be heated to a temperature of 60-70°C. By the end of the purge at the outlet of the apparatus, the gas must have a temperature of at least 40-50°C. The duration of the purge depends on the dimensions and shape of the products to be degreased and on the physicochemical properties of the solvents. Purging should be carried out until the smell of the solvent is completely removed. The purge procedure is the same as when warming up equipment from a cold state. It is necessary to exclude the ingress of air contaminated with solvent vapors into the room. 4.4.2. Purge of products intended for the storage and transportation of medical oxygen should be carried out until the solvent vapors in the gas are completely absent; during the control purge, no more than a two-fold gas exchange in the product within 1 hour should be provided. 4.4.3. Removal of residues of aqueous cleaning solutions should be carried out by washing the products with hot drinking water at a temperature of 70-80°C. Rinsing is stopped in the absence of foam in the water and a neutral reaction of the medium (PH-6-8) when checking with universal indicator paper according to TU 6-09-1181. 4.4.4. After degreasing the products with aqueous cleaning solutions by the "wiping" method, the remains of the solution are removed by rubbing with napkins moistened with warm water at a temperature of 35-40°C. Wiping the surface with napkins moistened with water ends after there are no traces of foam on the wiped surface and on the napkins. The pH of the last wash water should be 6-8. 4.4.5. Before drying products, they must be completely drained of water. Particular attention should be paid to the completeness of the removal of water from the internal cavities and pockets. Drying of metal products washed in water is carried out until complete removal of moisture by blowing with compressed air at a temperature of 100-120°C, and assembly units with non-metal parts at a temperature of 70-80°C. By the end of the purge, the air temperature at the outlet of the apparatus should be no more than 10-15°C lower than the temperature of the supplied air. Natural drying of parts of simple configurations and open surfaces is allowed in compliance with safety regulations. The break between the end of washing and drying of the product should not exceed 10-15 minutes. Spots of white plaque from aqueous washing solutions are allowed with an area of ​​\u200b\u200bno more than 10% of the surface of the washed products.

5. Degreasing quality control

5.1. Quality control of degreasing and technological parameters is carried out during the development of the technological process, as well as at the request of the Quality Control Department or the customer's representative. In the absence of control, the quality of degreasing must be guaranteed by the observance of the accepted technology. 5.2. The need to control the degreasing of products, the percentage of controlled products and the chosen method should be specified in the technological documentation. 5.3. Depending on the degreasing method and the design of the product, the quality of the degreasing is controlled by directly determining the content of fatty contaminants on the surface of the product after degreasing or indirectly, by determining the content of fatty contaminants in the solvent, before the control degreasing and in the drained product after the control degreasing, or on the surface of "witnesses". " degreased at the same time as the product. The consumption of the solvent during the control degreasing is 20-30% of the amount required for a single degreasing of the product. 5.4. Quality control of degreasing is carried out in accordance with OST 26-04-2574. 5.5. Temperature control of solutions, temperature and composition of gases is carried out by universal measuring instruments (thermometers, gas analyzers of any type). ______________________________ * An example entry is preferred.

Attachment 1

Reference

Explanation of terms

	Explanation
Degreasing	Technological operation of reducing the content of fatty contaminants to the standards established by regulatory and technical documents or technical documentation.
Skim equipment	Equipment, the content of fatty contaminants on the surface of which meets the standards.
Pollution	According to GOST 24869.
Fat contamination	Pollution consisting of mineral oils and other fatty substances.
	The amount of grease contaminants per unit surface of the product.

Annex 2

Features of degreasing various types of equipment

1. General Provisions

1.1. Equipment operating with oxygen in accordance with GOST 5583 and GOST 6331 is not degreased during operation, with the exception of liquid oxygen evaporators and other equipment in which fatty contaminants can enter oxygen. 1.2. Equipment operating with oxygen containing 0.01 mg / dm 3 of fatty contaminants or more must be degreased after the amount of fatty contaminants calculated by the formula reaches the norm

Where S- inner surface of the vessel, m 2 ; v- volume of oxygen filled or pumped into the vessel, dm 3 ; C - the content of fatty contaminants in oxygen, mg / dm 3; n- number of vessel fillings; m- permissible content of fatty contaminants according to OST 26-04-1362 or GOST 12.2.052, mg/m 2 . The equipment passport or other document should record the amount of oxygen passed through and the content of fatty contaminants in it. By change No. 2, this appendix was supplemented by clause 1.3 1.3. The need for degreasing of oxygen service equipment can be determined by a control degreasing. If the design of the product allows, control degreasing should be carried out in places of the most probable deposition and accumulation of fatty contaminants. It is allowed not to degrease the equipment if the oil content does not exceed the values ​​regulated by the normative and technical documents specified in clause 1.1. of this standard.

2. Degreasing air separation units

2.1. Degreasing of separation units in assembly is carried out only with group 1 solvents (see Table 1) of the standard. The use of group 2 solvents for these purposes is not permitted. 2.2. The amount of solvent required for degreasing depends on the size of the separation unit and the degree of oil contamination. The approximate amount of solvent required for a single flush of some blocks is given in table. 1. Table 1

Estimated solvent consumption for a single flush of air separation units

2.3. To avoid corrosion, before degreasing with solvents, all apparatuses of separation units must be thoroughly dried. 2.4. Before degreasing the air separation units, the equipment must be checked for tightness and all detected gaps must be eliminated. 2.5. Degreasing of communications and internal cavities of heat exchangers is carried out by circulation of the solvent in the washed cavities for 1-1.5 hours. 2.6. Degreasing of apparatuses (condensers, lower column cube, regenerators, etc.) is carried out by filling with a solvent up to 3/4 of the volume, followed by bubbling with air or nitrogen for 1-1.5 hours or by condensing solvent vapors. 2.7. The adsorbers are degreased after the adsorbent is removed from them by wiping the adsorber body and basket. It is not allowed to degrease assembled acetylene adsorbers. 2.8. The degreasing of the filter elements of expander filters is carried out with aqueous washing solutions, for example, in washing machines, or by circulating a solvent through a filter element in a special device. It is not allowed to degrease the filter fabric by hand washing in a solvent.

3. Degreasing of cryogenic vessels, cylinders and transport tanks

3.1. Vessels of liquid medical oxygen are degreased upon detection of fatty contaminants in liquid oxygen in an amount of 0.01 mg/dm 3 or more, confirmed in five consecutive analyzes. 3.2. Vessels and cylinders are degreased by filling with a solvent up to 1/3 of the vessel, followed by rotation or rocking in a special device. The specified equipment can also be degreased with a hot aqueous cleaning solution, filling the equipment with it or washing its walls by the jet method. 3.3. For degreasing transport tanks and vessels, the method of condensation of solvent vapors can be used. Before degreasing transport tanks and vessels by this method, the evaporators that complete them should be removed, which are degreased separately. In the vessel, pre-heated to a temperature of 30-40°C, solvent vapor is fed through the "fill-empty" valve. Air is expelled from the vessel through the gas relief valve during the first hour of solvent vapor supply. The condensate drains to the bottom of the vessel. If the pressure in the transport tank or vessel rises above 0.05 MPa (0.5 kgf / cm 2) when the solvent vapor is supplied, the vessel should be cooled by blowing cold air or nitrogen until the outlet gas temperature drops to a temperature of 293- 298 K (20-25°C), then continue degreasing. The condensate is drained and the content of fatty contaminants in it is determined. Degreasing is completed when the content of fatty contaminants in the drained solvent is not more than 20 mg/DM 3 . 3.4. Vessels and cylinders with hatches can be degreased by washing their walls with a jet method or wiping the inner walls of the vessels with cloth napkins moistened with a hot aqueous washing solution; after wiping, the remaining solution is drained through the bottom drain. The evaporator and lower drain communications are washed again with a clean solution. 3.5. When degreasing vessels using the “wiping” method, the following rules must be observed: - before degreasing, a vessel that has been in operation must be warmed up in accordance with clause 3.3. standard; — workers performing degreasing should be instructed on the rules and safe methods of working inside enclosed apparatus; - the person responsible for carrying out the degreasing must inspect the place of work and make sure that the vessel is warmed up and prepared for work; - when working, the requirements of the "Temporary standard instruction for the organization of safe gas hazardous work at enterprises of the USSR Ministry of Chemical Industry", approved by the USSR Gosgortekhnadzor and the USSR MHP, must be observed.

4. Degreasing liquid oxygen pumps

4.1. Parts of liquid oxygen pumps are degreased by immersion in baths, preferably with aqueous cleaning solutions, in accordance with the instructions in paragraph 4.3.3. standard. 4.2. Communications to the pump are degreased by circulating an aqueous washing solution or solvent or condensing solvent vapors in accordance with the instructions in section 8. 4.3. Flake graphite is degreased with a solvent in a separate vessel. After thorough mixing, the solvent is drained off, and the graphite is poured out and dried in the open air or in an oven until the smell of the solvent is completely removed.

5. Degreasing of gasification plants

5.1. Vessels of warm and cold gasifiers are degreased by filling with a solvent, followed by bubbling nitrogen or air. 5.2. Evaporators of gasification plants are degreased by circulation of solvents through them. The frequency of degreasing of evaporators operating with liquid oxygen in accordance with GOST 6331 is determined by formula 1, clause 1.2. while the content of fatty contaminants in oxygen is assumed to be 0.01 mg/dm 3 . Degreasing of gasifiers at a pressure of 15 MPa (150 kgf / cm 2) should be carried out at least after 1000 hours of plant operation.

The paragraphs are numbered according to the source.

5.4. After degreasing and purging the medical oxygen gasifier, the gaseous product is released into the atmosphere for 1 hour without increasing the pressure.

6. Degreasing of cryogenic cold gasifiers of the GKH type

6.1. When the gasifier is operated on oxygen according to GOST 6331, the control degreasing of one of the evaporators is carried out after the mass of oxygen passes through the gasifier, determined by the formula:

Where M- mass, t; F- internal area of ​​the gasifier panel, m 2 . Control degreasing is carried out with solvents of group 1 of the table. 1 standard in the amount of 20-30% of the total volume to be filled. After the control degreasing, the content of fatty contaminants in the solvent is determined according to OST 26-04-2574. 6.2. Degreasing of the remaining evaporators is carried out if the content of fatty contaminants exceeds the allowable standards according to 26-04-1362. Degreasing is carried out by the method of circulation with a solvent of group 1 of the table. 1 standard. 6.3. When using oxygen containing fatty contaminants more than 0.01 mg / dm 3, the gasifier (reservoir, valve cabinet, evaporators and pipelines) is degreased after the mass of oxygen, determined according to clause 1.2, passes through the reservoir. 6.4. Degreasing of the gasifier tanks is carried out by the method of condensation of solvent vapors in accordance with clause 4.3.5. standard. Evaporators are degreased using the solvent circulation method. Degreasing ends when the content of fatty contaminants in the drained condensate is not more than 20 mg/dm 3 .6.5. Spindle groups of fittings are degreased by wiping with aqueous detergent solutions. 6.6. Degreasing of spindle groups of fittings with solvents of group 1 tab. 1 standard is not allowed. Degreasing of evaporators with aqueous cleaning solutions is not allowed. 6.7. After degreasing, the gasifier is purged until the solvent residues are completely removed. Completeness of solvent removal should be verified by analysis. Purge of the medical oxygen gasifier should be carried out until the complete absence of solvent vapors in the gas during the control purge (no more than 2 mg/m3). 6.8. When oxygen is used in the gasifier in accordance with GOST 6331, degreasing of the tank, valve cabinet and pipelines is not performed.

7. Degreasing oxygen compressors

7.1. Small parts are degreased in accordance with clause 4.3.3. standard. 7.2. Degreasing of valves with solvents should be carried out only in disassembled form. 7.3. Large parts, for example, a cylinder, a cover, rods, pistons, etc., are degreased in baths with an aqueous washing solution or solvent, or by wiping the surfaces with cloths moistened with low-toxic solvents (see clause 4.3.7. of the standard) or hot water detergent solution. 7.4. Shell-and-tube refrigerators, moisture separators, receivers and other containers are filled with 1/3-1/2 volume of solvent, after which they are turned over. If the parts are degreased after depreservation, two or three times washing of the parts with a solvent is necessary. It is recommended to degrease these devices by solvent vapor condensation or to wash them with a hot cleaning solution (see clause 4.3.5. of the standard). 7.5. Coil coolers are degreased with a solvent or hot cleaning solution by circulation or filling (see clause 4.3.4.; 4.3.3. of the standard). 7.6. After degreasing, the compressor must be run in air or nitrogen for 2 hours. 7.7. Degreasing of oxygen turbocompressors is carried out in accordance with RTM 26-12-43.

8. Degreasing pipelines and hoses

8.1. The need for degreasing assembly pipelines with a pressure of more than 4.0 MPa (40 kgf / cm 2) is determined by the technical documentation, it is recommended to make a decision on degreasing after checking the open ends of the pipeline, in accordance with OST 26-04-2574. 8.2. Liquid oxygen pipelines are checked for the presence of fatty contaminants at least once a year, in the case when oxygen with a content of fatty contaminants higher than the requirements in accordance with GOST 6331 is transported through it. - entrance areas. Control is carried out according to section 5 of the standard. In case of exceeding the standard OST 26-04-1362, the entire pipeline is subjected to degreasing. 8.3. When degreasing by immersion in baths, the pipes are placed in special baths filled with aqueous cleaning solutions or solvents, and kept in accordance with the instructions in clause 4.3.3. standard. 8.4. For circulation degreasing, pipelines are connected to a special system equipped with a pump, through which aqueous cleaning solutions or solvents are pumped (see clause 4.3.4. of the standard). 8.5. Degreasing the inner surface of the pipes by filling is carried out as follows: technological plugs are installed on the ends of the pipes. A solvent is poured through the appropriate fitting in the plug, after which the fitting is closed, and the pipes or hoses are laid horizontally. The pipes should be in a horizontal position for 10-20 minutes, during which time they should be turned 3-4 times in order to wash the entire inner surface with a solvent. Pipes filled with solvent can also be moved in special rocking chairs or rotary mechanisms. 8.6. The sections of the installed pipeline are degreased by circulating a solvent or an aqueous cleaning solution. 8.7. The approximate solvent consumption required for a single degreasing of the inner surface of one linear meter of pipe is calculated by the formula:

(2)

Where Q- solvent consumption, dm 3 /m; D- inner diameter of the pipe, see Solvent consumption for a single degreasing of pipes is given in Table. 2. Table 2

Solvent consumption for single pipe degreasing

Continuation of the table. 2 Continuation of the table. 2 8.8. Small sections of pipelines can be degreased by wiping or jetting with an aqueous cleaning solution using special tools. 8.9. The outer surfaces of the ends for a length of 0.5 m during installation are wiped with napkins soaked in a solvent or an aqueous washing solution and dried in the open air. 8.10. All parts intended for connecting hoses to the tank must be degreased by wiping, if they were contaminated during storage. 8.11. Hoses of medical oxygen tanks are degreased together with the vessel. 8.12. Fat-free sections of pipelines to be stored or transported must be plugged and sealed. 8.13. Sections of pipelines subjected to chemical passivation or other types of chemical surface treatment before assembly may not be degreased if the requirements of clause 1.3 are met. standard. 8.14. Sections of pipelines and hoses, degreased during manufacture, received for installation with plugs and having the appropriate marks in the passport, are not degreased. 8.15. Assembly pipelines are not subjected to degreasing, with a pressure of up to 4.0 MPa (40 kgf / cm 2), if the pipeline sections before assembly or the assembly pipelines were cleaned from scale, slag, etc. by pickling, sandblasting and shot blasting. 8.16. The main pipelines and intershop pipelines of oxygen, with a pressure of up to 1.6 MPa (16 kgf / cm 2), as an assembly are not degreased if, before connecting individual pipes, visual inspection confirms the absence of stains of fatty contaminants on the surface of the pipelines, for which an act must be drawn up .

9. Degreasing fittings and appliances

9.1. Degreasing is carried out after manufacture, before installation and after repair, i.e. in cases where contamination of the fittings was possible. 9.2. The fittings are degreased in disassembled form with aqueous detergent solutions. It is allowed to pre-wipe with a cloth soaked in white spirit or kerosene. In this case, special attention should be paid to fire safety measures. 9.3. In case of technical necessity, it is allowed to degrease the fittings without dismantling. To determine the possibility of degreasing purchased fittings without dismantling, it is recommended to degrease it, dry it, and then disassemble and check for the residual content of fatty contaminants. If the residual content complies with the standards, in accordance with clause 1.1. standard, further fittings can be degreased without dismantling. Particular attention should be paid to the stuffing box and its packing. 9.4. When degreasing fittings without dismantling, the compatibility of all materials from which the fittings are made, especially seals, with the detergents used should be taken into account. 9.5. The valve is not subject to degreasing before its installation, if the degreasing was carried out at the factory (which must be confirmed by the accompanying documents or appropriate branding) and the packaging is not broken. 9.6. Gaskets made of rubber, paronite, fiber, fluoroplastic gland rings, parts made of fiberglass, polycarbonate and textolite are degreased by wiping with aqueous detergent solutions and rinsed with water. 9.7. Asbestos used for gland packing of fittings is degreased by calcination at a temperature of 300°C for 2-3 minutes. 9.8. Degreasing of devices for measuring flow and pressure is carried out according to OST 26-04-2158.

Annex 3

Mandatory

Solvent Requirements

Input control

Name of indicator

Control method

1. Appearance

Colorless, clear liquid

Determined visually

2. The content of mechanical impurities and water

It must be transparent and not contain foreign impurities suspended and settled on the bottom of the cylinder.

Pour the solvent into a glass cylinder with a diameter of 40-50 mm

3. Reaction of the environment

The water layer should not turn pink

The solvent in the amount of 15 cm 3 is placed in a separating funnel, 40 cm 3 of distilled water are added and shaken for 3-5 minutes; after settling, the aqueous layer is drained and methyl orange 0.1% aqueous solution is added to it

4. Oil content

Section 2 of the standard, tab. 2

According to OST 2 6-04-2574

Appendix 4

Mandatory

Preparation of baths with aqueous cleaning solutions, their control and adjustment

1. Composition of baths

1.1. The amount of each component provided by the recipe is calculated based on the composition of the baths and its useful capacity. The components of the solution, depending on local conditions, can be dissolved individually in auxiliary vessels or directly in the bath in which the degreasing is carried out. Dissolution is carried out by heating to a temperature of 60-70°C with vigorous stirring of the solutions with mechanical agitators or air bubbling. 1.2. After drawing up the bath, determine the total alkalinity of the freshly prepared composition according to the method below.

2. Control and adjustment of baths

2.1. General requirements

2.1.1. Control analyzes of the composition of aqueous detergent solutions in degreasing baths are carried out at least 2 times a week by determining the total alkalinity of the solution. Baths are adjusted according to the results of control analyses. The general change of the aqueous washing solution with regular loading of the bath is carried out once a week. 2.1.2. When using the baths, do not allow the accumulation of contaminants on the surface of the solutions. Regularly remove grease from the surface using special tools (perforated spoon or mesh) or special grease traps. 2.1.3. Before taking a sample of the solution for control analysis, it is necessary to bring the solution to the desired level and mix.

2.2. Determination of the total alkalinity of a solution

Amendment No. 1, approved by the Deputy Minister of Chemical and Petroleum Engineering on January 4, 1987, amended subparagraph 2.241 of this Appendix, which shall enter into force on July 1, 1987.Amendment No. 2 to subparagraph 2.2.1 of this appendix has been amended 2.2.1. Used reagents, solutions and utensils: - hydrochloric acid, according to GOST 3118, 0.1 m solution; - methyl orange indicator according to TU 6-09-5171, 0.1%; - distilled water, according to GOST 6709; - conical flasks, according to GOST 25336, with a capacity of 250 cm 3; - measured pipettes, according to GOST 1770, with a capacity of 100 cm 3; - measuring burette, according to GOST 1770, with a capacity of 25 cm 3. 2.2.2. To carry out the determination, 5 cm 3 of a cooled aqueous washing solution is placed in a 250 cm 3 conical flask, diluted with water to 100 cm 3, 2-3 drops of methyl orange solution are added and titrated with 0.1 N, HCl until the yellow color changes to pale pink. 2.2.3. The total alkalinity of the solution in terms of NaOH in g / dm 3 is calculated by the formula:

Where q- amount of 0.1 n solution HCl, spent on titration, cm 3; 0.004 - solution titer HCl, G; To- correction to the titer of 0.1 N solution HCl;m- the amount of solution taken for analysis, cm 3.

2.3. Bath adjustments

2.3.1. According to the results of control analyzes, the baths are adjusted if the total alkalinity of the solution decreases by more than 20%. 2.3.2. When adjusting, all components of the solution are added to the bath. The calculation of the added amount is carried out according to the main component, which determines the total alkalinity of the solution. For example, according to the control analysis of the composition bath: NaOH - 10 g; Na 3 PO 4 -15 g; Na 2 SiO 3 -2 g; OP-7 - 2-3 g; H 2 O - 1 dm 3 total alkalinity decreased by 35%. When adjusting, it is necessary to add to the bath based on 1 dm 3: NaOH - 3.5 g; Na 2 SiO 3 - 0.7 g; Na 3 PO 4 - 5.2 g; OP-7 - 0.7-1 g. Amendment No. 2 amended this ListAmendment No. 1, approved by the Deputy Minister of Chemical and Petroleum Engineering on January 4, 1987, amended this List, effective from July 1, 1987.

List of reference normative and technical documents (NTD)

Designation

Name

Sheet (page)

GOST 9.010-80

ESZKS. Compressed air for spraying paints and varnishes. Technical requirements. Rules and methods of control

GOST 9.305-84

E C 3 COP. Metallic and non-metallic, inorganic coatings. Operations of technological processes for obtaining a coating

GOST 12.1.001-83

SSBT. Ultrasound. General safety requirements.

GOST 12.1.004-85

SSBT. Fire safety. General requirements.

GOST 12.1.014-84

SSBT. Work area air. Method for measuring the concentration of harmful substances with indicator tubes.

GOST 12.1.016-79

SSBT. Work area air. Requirements for methods for measuring concentrations of harmful substances.

GOST 12.1.019-79

SSBT. Electrical safety. General requirements.

GOST 12.2.052-81

SSBT. Equipment operating with gaseous oxygen. General safety requirements

GOST 12.3.008-75

SSBT. Production of metallic and non-metallic inorganic coatings. General safety requirements.

GOST 12.4.011-89

SSBT. Means of protection for workers. Classification.

GOST 12.4.026-81

SSBT. Signal colors and safety signs

GOST 17.2.3.02-78

Protection of Nature. Atmosphere. Rules for Establishing Permissible Emissions of Harmful Substances by Industrial Enterprises

Trisodium phosphate. Specifications.

Nephrases S2-80/120 and SZ-80/120. Specifications.

GOST 1770-74E

Ware measured laboratory glass. Cylinders, beakers, flasks. Specifications.

GOST 22 63-79

Sodium caustic technical. Specifications.

GOST 2874-82

Drinking water. Hygienic requirements for quality control.

GOST 3118-77

Hydrochloric acid. Specifications.

GOST 3134-78

Gasoline solvent for the paint and varnish industry. Specifications.

GOST 4328-77

Reagents. sodium hydroxide. Specifications.

GOST 4753-68

Kerosene lighting. Specifications.

GOST 5583-78

Oxygen gaseous technical and medical. Specifications.

GOST 6331-78

Oxygen liquid technical and medical. Specifications.

GOST 6709-72

Distilled water.

GOST 8505-80

Nefras-S 50/170. Specifications.

GOST 9293-74

Nitrogen gaseous and liquid. Specifications.

GOST 9337-79

Sodium phosphate 12-water. Specifications.

GOST 9976-83

Trichlorethylene technical. Specifications.

GOST 2533 6-82

Ware and laboratory glassware. Type, main parameters and dimensions.

GOST 10652-73

Ethylenediamine disodium salt - N, N, N ¢, N ¢ tetraacetic acid, 2-water (Trilon-B).

GOST 13078-81

Liquid sodium glass. Specifications.

GOST 15899-79

Freon 114V2. Specifications.

GOST 19906-74

Sodium nitrite technical. Specifications.

OST 26-04-13 62-75

OST 26-04-2138-81

Temporary anticorrosive protection of products.

OST 26-04-2158-78

SSBT. Means for measuring flow and pressure. Safety requirements for use in an oxygen gas environment.

OST 26-04-2574-80

Gases, cryogenic products, water. Methods for determining the content of mineral oils.

OST 26-04-2578-80

Gases, cryoproducts. Chromatographic method for the determination of impurities in organochlorine solvents.

OST 26-04-2600-83

The equipment is cryogenic. General specifications.

RTM 26-12-43-81

Degreasing of centrifugal oxygen compressors.

TU 6-01-927-76

Trichlorethylene stabilizer (STAT-1) .

TU 6-02-640-80

Nonionic drug synthamide-5.

TU 6-09-1181-76

Universal indicator paper for determining pH 1-10 and 7-14.

TU 6-09-5171-84

Indicator methyl orange (para-dimethylanino-azobenzenesulfonic acid sodium)

TU 6-01-956-86

Tetrachlorethylene (perchlorethylene)

TU 6-14-577-88

Detergent Sintanol DS-10

TU 6-15-978-76

Synthetic detergent HC-8.

Preparation KM-2.

TU 38.103 62-87

Surfactant NEONOL AF9.12

TU 38-10761-75

Synthetic detergent Vimol.

Detergent technical Vertolin -74.

TU 38-107113-78

Detergent technical TNS-31.

TU 38.50724-84

Degreasing equipment designed to work with liquid oxygen

from "Liquid Oxygen Safety"

In the process of manufacturing parts of oxygen equipment, storing them under production conditions, assembling and mounting the product, the surfaces of parts can be contaminated with organic and combustible substances (oil, grease, etc.). In addition, many parts of oxygen equipment units are covered with conservation grease for the period of storage. Contact with liquid oxygen of such equipment without preliminary cleaning of its surfaces from organic substances (degreasing) can lead to detonation or ignition of the organic matter film - liquid oxygen system. Cleaning oxygen equipment from organic and combustible substances is achieved by degreasing individual parts before assembly, assemblies or the entire product after its installation.
The equipment is also degreased during the period of its operation within the terms established by the design and technological documentation. The degree of degreasing of the equipment must be such that the thickness of the layer of fatty contaminants on surfaces in contact with oxygen does not exceed the values ​​at which combustion and detonation are impossible.
The procedure for degreasing oxygen equipment, the requirements for detergents and solvents, and the cleanliness of degreasing surfaces in contact with oxygen are regulated by the industry standard OST 26-04-312-71 Oxygen equipment. degreasing methods. Applied materials.
According to the ability to create combustible and explosive mixtures with air and oxygen, solvents are divided into two groups. The first includes fire and explosion-free hazardous solvents that are used to degrease parts, assemblies and assembled products. Solvents belonging to the second group are explosive and flammable when in contact with liquid oxygen, and their vapors mixed with air and gaseous oxygen can form combustible and explosive systems. Such solvents can only be used under conditions that ensure their complete removal from the internal cavities of degreased assemblies and parts.
Aqueous cleaning solutions are used for degreasing individual parts, fittings, pipelines and the entire product when their design makes it possible to completely drain the cleaning solution and remove its residues by washing with water.
The duration of surface cleaning and the quality of degreasing depend on the temperature of aqueous cleaning solutions. The most effective is degreasing at a solution temperature of 60-80 °C.
If oil is found in liquid oxygen in an amount of more than 0.4 g/m, confirmed in five consecutive analyzes (GOST 6331-68), degreasing of the blocks should be carried out immediately.
Air separation units intended for the production of medical oxygen are degreased immediately upon detection of oil in liquid oxygen in an amount of 0.01 g/m3 or more, confirmed in five consecutive analyzes. Degreasing of air separation units can be omitted within the time periods specified above, if the means of protecting the unit from oil ensured the absence of oil in liquid oxygen during the entire period of operation of the unit after the next degreasing within the sensitivity of the analysis method.
If there is no calculation data for degreasing periods, then degreasing should be carried out every 6 months.
For degreasing, carbon tetrachloride, trichloroethane, tetrachlorethylene, freon-113, as well as hot aqueous washing solutions are used.
Oxygen Dewars should be degreased at least once every 6 months. Degreasing must be carried out with one of the solvents (see Table 39), for example, carbon tetrachloride, freon-113, etc. The solvent is poured in an amount of at least 1/3 of the capacity of the vessel to be degreased. The mouth is closed with a rubber stopper and the vessel is shaken by turning in different directions so that the entire surface of the inner vessel is irrigated with solvent. Rinsing should be carried out for at least 10 minutes, after which the solvent must be poured out, the vessel must be turned upside down and held in this position for 1-2 hours, and then dried in an upright position for a day (at least).
Parts of liquid oxygen pumps that come into contact with oxygen are degreased before final assembly, after depreservation or repair, and also during the operation of the product (for example, a gasifier) ​​that includes the pump.
Gasifier evaporators are degreased by circulating solvent through them. Degreasing should be carried out at least every 1000 hours of plant operation.
Liquid oxygen pipelines are degreased during manufacture or installation, after repair, during which contamination of internal surfaces is possible, as well as during operation. If the oil content in the transported liquid oxygen exceeds 0.01 g/m, then the pipeline is degreased at least once a year.
After degreasing, solvent residues or aqueous cleaning solution must be removed from the equipment. This is achieved by purging the product with nitrogen or air preheated to 60-70°C. Only nitrogen is used to remove gasoline residues.
The duration of the purge depends on the dimensions and shape of the products to be degreased, as well as on the physicochemical properties of the solvent. Purging should be carried out until the smell of the solvent is completely removed. Control of the completeness of the removal of solvent vapors from the product is carried out according to the results of the analysis (OST 26-04-312-71).
Residues of cleaning solutions are removed by washing the product with water. Rinsing is stopped when the medium is neutral (pH = 6-8) and there is no foam in the water. The neutrality of the medium is checked using a universal indicator paper.
Before drying, water must be completely removed from parts and assemblies. Drying is carried out with dry compressed air, followed by holding in electrical cabinets at 100-120 ° (2) or with dry hot compressed air at a temperature of 90-100 ° C. For parts of a simple design, natural drying is allowed.
Carbon tetrachloride Trichlorethylene.
Kerosene (in terms of carbon). .

No. ________ "__" ______ 20__

Representative of the builder or customer _____________________________________

(job title,

Representative of the person carrying out the construction, __________________________

(job title,

__________________________________________________________________________

surname, initials, details of the representation document)

Representative of the person carrying out the construction on the issues of construction control __________________________________________________________________

(job title,

__________________________________________________________________________

surname, initials, details of the representation document)

Representative of the person carrying out the construction, performing the technical supervision of the installation work, (chief engineer) _____________________________

__________________________________________________________________________

Representative of the person preparing project documentation, ______

__________________________________________________________________________

(position, surname, initials

__________________________________________________________________________

details of the representation document)

Representative of the person carrying out the construction, who performed the degreasing of the equipment, _______________________________________________

(position, surname, initials,

__________________________________________________________________________

details of the representation document)

as well as other representatives of persons involved in degreasing, _________________

__________________________________________________________________________

(position, surname, initials,

__________________________________________________________________________

details of the representation document)

carried out control of processes and consideration of the results of degreasing of equipment, fittings, pipelines, assembly units and parts (hereinafter referred to as the product), presented by ____________________________________________

(name of the person, in fact

__________________________________________________________________________

presenting the product for degreasing)

and have drawn up this act as follows:

1. The product has been degreased:

a) technological equipment (apparatus, container, etc.)

b) fittings of the same type

c) pipeline, pipeline network

d) assembly unit, detail

2. Accompanying documents are presented __________________________________

__________________________________________________________________________

__________________________________________________________________________

as well as project documentation for non-standard equipment ________________

__________________________________________________________________________

(number, other details of the drawing, name of the design

__________________________________________________________________________

documentation, information about persons carrying out

__________________________________________________________________________

preparation of a section of project documentation)

3. Documents were presented confirming the compliance of the product with the requirements for it, including:

a) for compliance with the requirements of the technical documentation of manufacturers and design documentation of developers, technical regulations (norms and rules), other regulatory legal acts _______________________________

(Name

__________________________________________________________________________

document of conformity, date, number, other details)

b) the results of examinations, surveys, laboratory and other tests and work performed, carried out in building control

__________________________________________________________________________

(document name, date, number, other details)

4. Necessary tests and tests have been carried out ___________________________

__________________________________________________________________________

(document name, date, number, other details)

5. Documents were presented confirming the quality of degreasing of the product from the manufacturer, ______________________________________________________________

__________________________________________________________________________

(document name, date, number, other details)

6. The product is manufactured (delivered) __________________________________________

(name of the manufacturer (supplier, intermediary),

__________________________________________________________________________

name, number and date of issue of the certificate of state registration, PSRN, TIN,

__________________________________________________________________________

postal details, telephone, fax - for legal entities;

__________________________________________________________________________

surname, name, patronymic, passport data,

__________________________________________________________________________

place of residence, telephone, fax - for individuals)

7. Characteristics of the product subjected to degreasing of internal surfaces, ______________________________________________________________

(product purpose, technological

__________________________________________________________________________

environment in the product, its condition and characteristics,

__________________________________________________________________________

requirements for cleanliness of internal surfaces)

8. A work permit has been presented for work

__________________________________________________________________________

(document name, date, number, other details)