I. Confirmation of Preparations for Ball Valves before Installation
1. To ensure that the installation position of the ball valve is in the coaxial position of the pipeline, the two flanges on the pipeline should be kept parallel to ensure that the pipeline can bear the weight of the ball valve itself. If it is found that the pipeline can not bear the weight of the ball valve, the pipeline should be equipped with corresponding support before installation.
2. To confirm whether there are impurities and welding slag in the pipeline, the control valve must clean the pipeline.
3. Check the nameplate of the ball valve, and operate the ball valve fully open and closed several times to confirm that the valve can work properly, and then check the details of the valve comprehensively to ensure that the valve is intact.
4. Remove the protective caps at both ends of the valve, check whether the valve body is clean, and clean the inner cavity of the valve. Because the sealing surface of the valve is spherical, even small debris may cause damage to the sealing surface.
II. Installation of Ball Valves
1. Any section of the ball valve can be installed at the upstream end. Shanghai Nippon-American ball valve handle ball valve can be installed at any position in the pipeline. If the ball valve with actuator (such as gearbox, electric-pneumatic actuator) is equipped, it must be installed vertically, and the valve inlet and outlet are in the horizontal position.
2. Install gasket between ball valve flange and pipeline flange according to pipeline design requirements.
3. Bolts on flanges should be tightened symmetrically, successively and evenly.
4. If the ball valve adopts pneumatic and electric actuators, complete the installation of air source and power source according to the instructions.
3. Inspection of Ball Valve after Installation
1. After installation, start the ball valve open and close several times. It should be flexible, even in force, and the ball valve works normally.
2. According to the requirement of pipeline pressure design, the sealing performance of the joint of ball valve and pipeline flange is tested after the pressure is turned on.
IV. Maintenance of Ball Valves
1. Only by removing the pressure before and after the ball valve can the ball valve be disassembled and decomposed.
2. In the process of decomposition and reassembly of ball valves, it is necessary to protect the sealing parts, especially the non-metallic parts, such as O-rings and other parts, with special tools.
3. Bolts must be tightened symmetrically, step by step and evenly when the ball valve body is reassembled.
4. Cleaning agent should be compatible with rubber parts, plastic parts, metal parts and working media (e.g. gas) in ball valves. When the working medium is gas, the metal parts can be cleaned with gasoline (GB484-89). Non-metallic parts are cleaned with pure water or alcohol.
5. Decomposed individual parts can be washed by immersion. Metallic parts that remain undissolved can be scrubbed with clean, fine silk cloth impregnated with detergent (to avoid fibers falling off and adhering to the parts). When cleaning, all the grease, dirt, glue and dust adhering to the wall should be removed.
6. Non-metallic parts should be removed from the cleaning agent immediately after cleaning, and should not be immersed for a long time.
7. After cleaning, it needs to be assembled after the wall cleaning agent evaporates (can be wiped with silk cloth without soaking detergent), but it should not be put on hold for a long time, otherwise it will rust and be polluted by dust.
8. New parts should also be cleaned before assembly.
9. Use grease to lubricate. Lubricating grease should be compatible with ball valve metal material, rubber parts, plastic parts and working media. When the working medium is gas, such as Te221 grease can be used. A thin layer of grease is coated on the surface of the sealing groove, a thin layer of grease is coated on the rubber seal, and a thin layer of grease is coated on the sealing surface and friction surface of the valve stem.
10. Metal debris, fibers, grease (except for prescribed use) dust and other impurities, foreign bodies, etc. shall not be allowed to contaminate, adhere to or stay on the surface of the parts or enter the inner cavity when assembling.
