JB/T 6977-1993 Technical conditions for rust prevention pretreatment of mechanical products
Some standard content:
Machinery Industry Standard of the People's Republic of China
JB/T 6977-93
Technical Conditions for Pretreatment of Rust Prevention of Mechanical Products
Published on July 27, 1993
Ministry of Machinery Industry of the People's Republic of China
Implementation on July 1, 1994
Mechanical Industry Standard of the People's Republic of China
Technical Conditions for Pretreatment of Rust Prevention of Mechanical Products
1 Subject Content and Scope of Application
JB/T6977-93
This standard specifies the technical requirements for cleaning, cleaning methods and inspection methods for cleanliness of pretreatment of rust prevention. This standard applies to the cleaning of pretreatment of rust prevention between processes of steel machinery products, rust prevention in intermediate warehouses and rust prevention before sealing of finished products, and also applies to the cleaning of steel metal products before surface treatment.
2 Reference standards
GB4879 Anti-rust packaging
JB4322 Water-based metal cleaning agent and test method 3 Technical requirements for cleaning
3.1 Selection of cleaning agent
3.1.1 When selecting cleaning agent, you can choose the cleaning agent specified in Appendix A (reference) or other cleaning agents. 3.1.2 According to the material of the cleaning part, the type and degree of contamination of the dirt or the cleanliness to be achieved, or when it is difficult to clean the surface of the cleaned part, one or more cleaning agents can be used to remove the dirt in stages. 3.2 Cleaning equipment
, 3.2.1 Cleaning equipment and auxiliary containers should be made of materials suitable for cleaning agents, and if necessary, they should have heating devices, stirring devices, filtering devices, ultrasonic devices, conveying devices, ventilation and exhaust devices, etc. 3.2.2 Wiping tools are brushes, etc., and wiping materials are non-linting fabrics and equivalent porous materials. 3.2.3 The spray device is composed of a pump, a pressure gauge, a nozzle, etc. 3.2.4 The vapor degreasing is composed of a heater, a cooling tube, a moisture separator, a thermometer, etc. 3.2.5 The DC power supply for electrolytic degreasing is composed of an ammeter, a voltmeter, and insoluble electrodes such as iron, carbon, titanium, and platinum. 3.3 Operation precautions
3.3.1 Safety protection measures must be adopted during operation. 3.3.2 The process conditions can be adjusted according to the batch, shape, size, material, and degree of dirtiness of the workpieces to be cleaned. 3.3.3 The surface that is prone to rust after cleaning must be dried in time and properly treated with rust prevention. 3.3.4 The cleaned workpiece must not be touched with bare hands. 4 Cleaning methodswww.bzxz.net
The cleaning methods in this standard include wiping cleaning, immersion cleaning, spray cleaning, vapor cleaning, and electrolytic cleaning. These methods are generally used alone or in combination.
4.1 Wiping cleaning method
4.1.1 Use a wiping tool containing a cleaning agent to wipe the surface of the part to be cleaned to remove dirt, then dry it. If necessary, wipe it again with a cleaning tool before drying.
4.1.2 When wiping with acid to remove rust, immediately neutralize with alkali, wash with water, and then dry it. However, if wiping with phosphoric acid, the neutralization and subsequent processes can be omitted.
Approved by the Ministry of Machinery Industry on July 27, 1993
Implemented on July 1, 1994
JB/T 697793
4.1.3 The residual alkali and acid test shall be carried out in accordance with the provisions of Article 4.1.4 of GB4879. 4.2 No-smear cleaning method
4.2.1 Immerse the part to be cleaned in the cleaning agent at room temperature or under heating, and keep lifting to remove dirt. 4.2.2 When using solvent cleaning agents, the parts should be dried naturally or blown dry with hot air after cleaning. 4.2.3 When using surfactants or emulsion cleaning agents, the parts should be washed with water and dried after cleaning, but anti-rust emulsion cleaning agents can be dried naturally after cleaning.
4.2.4 When using acid or alkali cleaning agents, the parts should be washed with water after cleaning, or the necessary neutralization, washing with water and drying should be carried out according to the requirements of the anti-rust process. 4.2.5 If necessary, the residual acid or alkali should be tested in accordance with the provisions of Article 4.1.3. 4.3 Spray cleaning method
4.3.1 Spray the cleaning agent at room temperature or heated on the parts to be cleaned to remove dirt. 4.3.2 When using acid or alkali, the parts should be washed with water after cleaning, or the necessary neutralization, washing with water and drying should be carried out according to the requirements of the anti-rust process. 4.3.3 If necessary, the residual acid or alkali should be tested in accordance with the provisions of Article 4.1.3. 4.4 Steam cleaning method
4.4.1 Place the cleaning agent in the degreasing device and heat it to an appropriate temperature according to the type of cleaning agent. 4.4.2 Pass cooling water into the cooling pipe at the steam outlet of the clean room to condense the solvent vapor for recovery or recycling. 4.4.3 Place the cleaned parts in the solvent vapor and clean them for a certain period of time to remove dirt. 4.4.4 After cleaning, the cleaned parts should be dried naturally or blown dry with hot air. 4.5 Electrolytic cleaning method
4.5.1 Place the cleaning agent in the electrolytic cell (normal temperature or heated), and then immerse the cleaned parts in the cleaning agent to become an electrode to energize and remove the dirt attached to it.
4.5.2 The energization method has the following methods:
Anode electrolysis method: the cleaned parts are used as anodes; a.
Cathode electrolysis method: the cleaned parts are used as cathodes, and periodic reversing electrolysis method: the cleaned parts are exchanged between cathodes and anodes at appropriate time intervals. After the dirt is removed from the cleaned parts, they should be washed with water or hot water and dried if necessary. 5 Cleanliness test methods
The cleanliness test methods of this standard include visual inspection, wiping method, water hanging method, spray method, pressure spray method, contact angle method, copper sulfate method, electroplating method, weight method and fluorescence method. These methods are generally used alone or in combination. 5.1 Visual inspection method
According to Article 4.1.1 of GB4879.
5.2 Wiping method
According to Article 4.1.2 of GB4879.
5.3 Water hanging method
Immerse the cleaned surface in water and lift it up (when the cleaning agent used is alkali, it can also be etched with 3% to 5% dilute hydrochloric acid for 3 to 5 seconds before immersing in water, and then rinsed with water). Leave it for 10 seconds and observe the water film on the clean surface. If the water film is complete and continuous, it is qualified, otherwise it is unqualified.
5.4 Spray method
On the clean and dried surface, use a common manual sprayer to spray distilled water. When spraying, make the clean surface tilt 5°~10° from the vertical plane, and the distance between the nozzle and the sprayed surface is 15~30cm. Spray in a state where water droplets do not flow down. After spraying, let it stand for 30~60s. If the water film is complete and continuous, it is qualified, otherwise it is unqualified. 5.5 Pressure spray method
On the clean and dried surface, use a common manual sprayer to spray distilled water or distilled water with added agent with 60kPa (450mmHg) compressed air. When spraying, make the clean surface tilt 5°~10° from the vertical plane, and the distance between the nozzle and the sprayed surface is 60cm. Spray 30~40B. 2
JB/T697793
After spraying, place it for 30 to 60 seconds. If the water film is complete and continuous, it is qualified, otherwise it is unqualified. 5.6 Contact angle method
Place the clean surface on the support table of the contact angle measuring instrument, open the lower hole of the dripping point, start the piston of the micro-burette to drip water drops, and immediately activate various micro-movements after the water drops fall, so that the water drop image is in the field of view of the measuring instrument. Read the contact angle about 1 minute after the water drop falls on the protractor. Measure 4 to 5 points on each surface of the cleaned surface, and take the average value as the contact angle. The contact angle of the oil-contaminated surface is large, and the contact angle of the clean surface is close to 0. The length of time after degreasing has a great influence on the contact angle. The time of measurement after degreasing and the determination of the size of the contact angle are determined by the upper and lower processes.
5.7 Copper sulfate method
Immerse the clean surface in an acidic copper sulfate aqueous solution [copper sulfate (chemically pure) 50g/L, sulfuric acid (chemically pure) 20g/L] for 1 minute, then lift it up, wash it with water, and observe its clean surface. If the copper film is uniform, it is qualified. If there is leakage plating, spots or bubbles, it is unqualified. 5.8 Electrolysis method
Mix the bonding liquid composed of nickel sulfate (chemically pure) 240g/L, ammonium fluoride (chemically pure) 45g/., boric acid (chemically pure) 30g/1. and appropriate additives, at pH 4.0~5.6, temperature 50℃, the anode is a nickel plate, the cathode is a cleaned test piece, the anode current density is 4A/dm2 and under stirring conditions, electroplate for 20 minutes, and wash with water or hot water and dry immediately after plating. 5.8.1 Appearance inspection
If the coating is smooth and complete, it is qualified. If there is leakage, spots, fog, stripes, or pinholes, it is unqualified. 5.8.2 Thermal shock test
Put the test piece in a furnace at 200C and heat it for 10 minutes. Take it out and immediately immerse it in water at room temperature for quenching. Observe the surface condition of the coating. If there is no peeling or blistering, it is qualified. Otherwise, it is unqualified. 5.9 Gravimetric method
According to Chapter 4 of JB4322.
5.10 Fluorescence method
According to the provisions of Chapter 5 of JB4322.
See Table A1 for commonly used cleaning agents.
A Bath agent
D Surfactant
JB/T 697793
Appendix A
Cleaning agent
Aviation washing gasoline (GB1789)
Aviation washing gasoline (GB1789) plus a small amount of replacement anti-rust oil
Additive oil
Kerosene for lamps (GB253)
Light diesel (GB252)
Isopropyl alcohol (GB7814)
Trichloroethylene
Tetrachloroethylene
Methylene diamine
Tricyanotrifluoroethane
|Methyl chloroform
Tetraammine carbon
Sodium hydroxide
Sodium carbonate
Sodium bicarbonate
Sodium silicate
Sodium metasilicate
Water glass
Sodium phosphate
Sodium tripolyphosphate
Sodium hexametaphosphate
Sodium pyrophosphate
Anionic surfactant
Nonionic surfactant
Amphoteric surfactant
No. 120, No. 190
Chemical pure
Chemical pure
Industrial grade or chemical pure
Industrial Grade or chemical pure
Industrial grade or chemical pure
Industrial grade or chemical pure
Industrial grade or chemical pure
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Suitable Scope of application: Mainly used for immersion cleaning, spray cleaning and steam cleaning, etc., among which A-1~A-8 are mainly used for wiping cleaning, mainly used for stain cleaning and spray cleaning, among which B2 and B-3 can also be used for wiping cleaning, mainly used for immersion cleaning, spray cleaning and electrolytic cleaning, mainly used for correct cleaning, spray cleaning and electrolytic cleaning. E-emulsion cleaning agent Additional instructions: JB/T 6977-93 Continued Table A1 Use surfactant to emulsify petroleum solvent and water. This standard is proposed and managed by Wuhan Materials Protection Research Institute of Ministry of Machinery Industry. This standard was drafted by the Wuhan Materials Protection Research Institute of the Ministry of Machinery Industry. The main drafters of this standard are Wu Laixing, Chen Yuezhen, Liu Yiwu, Liu Han and Pan Feng. Grade
Scope of application
Mainly used for rust cleaning
and spray cleaning
People's Republic of China
Mechanical Industry Standard
Pretreatment of mechanical products for rust prevention
Cleaning Technical Conditions
JB/T697793
Published by the Mechanical Standardization Research Institute of the Ministry of Machinery Industry Printed by the Mechanical Standardization Research Institute of the Ministry of Machinery Industry (Beijing 8144 Mailbox
Ministry of Industry and Information Technology 100081)
Copyright reserved
No reproduction allowed
2 Words: 10,000
Format: 880×12301/16
Printing sheet: 1/2
First edition in April 1994
First printing in April 1994
Print run: 00,001-500
Number: 1421
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