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I. Installation of Ball Valves Preparations before installation 1. The pipelines before and after the ball valve are ready. The pipes at the front and back should be coaxial, and the sealing surfaces of the two flanges should be parallel. The pipe must be able to support the weight of the ball valve; otherwise, appropriate supports must be provided on the pipe. 2. Blow out the pipes upstream and downstream of the valve to remove any oil, welding slag, and other impurities from within them. 3. Check the markings on the ball valve to ensure that it is in good condition. Open and close the valve several times to confirm it is working properly. 4. Remove the protective covers from the connection flanges at both ends of the ball valve. 5. Inspect the valve orifice, remove any possible dirt, and then clean the orifice. Even tiny particles of foreign matter between the valve seat and the ball can damage the sealing surface of the valve seat. Installation: 1. Install the valve on the pipeline. Either end of the valve can be installed at the upstream side. A handle-driven valve can be installed at any position on the pipeline. However, ball valves equipped with gearboxes or pneumatic drivers should be installed vertically, that is, on horizontal pipes, with the driving mechanism located above the pipe. 2. Seals should be installed between the valve flange and the pipeline flange in accordance with the requirements of the pipeline design. 3. The bolts on the flanges must be tightened symmetrically, one by one, and evenly. 4. For connecting pneumatic pipelines (when a pneumatic driver is used), inspections after installation are required: 1. Operate the driver to open and close the ball valve several times; it should move smoothly without any resistance, confirming that it is working properly. 2. Check the sealing performance of the joint between the pipe and the ball valve’s flange according to the pipeline design requirements. Preparations before installing the ball valve: 1. The pipelines must be ready before and after installing the ball valve. The pipes at the front and back should be coaxial, and the sealing surfaces of the two flanges should be parallel. The pipe should be able to support the weight of the ball valve; otherwise, the pipe must be equipped with appropriate supports. 2. Install valves before and after the outlet pipe to remove oil, slag, and other impurities from the pipe. 3. Check the markings on the ball valve to ensure it is in good condition. Open and close the valve several times to verify its proper operation. 4. Remove the protection from the flange at the end of the ball valve. 5. Check whether there is dirt in the valve holes, and then clean them. Even small foreign particles between the valve seat and the ball can damage the sealing surface of the valve seat. Ball valve installation: 1. Connect the valve to the pipeline. Either end of the valve can be installed at the upstream side. Valves driven by a handle can be installed at any position on the pipeline. However, the ball valve should be installed vertically together with the gearbox or pneumatic actuator; that is, in a horizontal pipeline, the transmission mechanism is located within the pipeline. Sealing gaskets 3 should be installed at the valve flange and the pipeline flange in accordance with the pipeline design requirements. The bolts on the flanges must be tightened symmetrically, progressively, and evenly. When connecting pneumatic pipelines (when using a pneumatic driver), after the ball valve is installed, the following checks should be carried out: 1. Operate the transmission mechanism to open and close the ball valve several times – it should move smoothly without any resistance, confirming its proper functioning. 2. Check the sealing performance of the ball valve joints in accordance with the pipeline design requirements. II. Maintenance of the Ball Valve ◆ Before disassembling the ball valve, it is necessary to ensure that the pressure in the upstream and downstream pipes has been released first. ◆ During disassembly and reassembly, care must be taken to prevent damage to the sealing surfaces of the components, especially those made of non-metallic materials. The bolts on the flanges must be tightened symmetrically, gradually, and evenly. ◆ The cleaning agent used must be compatible with the rubber, plastic, metal components inside the ball valve, as well as with the working medium (such as gas). When the working medium is gas, metal parts can be cleaned with gasoline (gb484-489). Non-metallic parts should be cleaned with pure water or alcohol; individual components can be cleaned by immersion. ◆ Metal components that contain unreduced non-metallic parts can be wiped with clean, fine silk soaked in cleaner (to prevent fibers from falling off and sticking to the components). ◆ Non-metallic parts should be removed from the cleaning solution immediately after cleaning; they should not be left immersed for long periods. ◆ All non-metallic residues on surfaces, such as grease, dirt, glue, and dust, should be removed from the cleaning solution right after cleaning; they should not be left there for long. After cleaning, the surfaces should be dried (a silk cloth may be used for this purpose), and then the components can be assembled. However, they should not be left in that state for long, as otherwise they will rust and get contaminated with dust. ◆ New components should be cleaned and lubricated with grease before assembly. The grease should be compatible with the ball valve’s metal components, rubber parts, plastic parts, and the working medium. ◆ Apply a thin layer of grease on the surface of the sealing installation groove, as well as on the rubber seals. A thin layer of grease should also be applied to the sealing surfaces and friction surfaces of the valve stem. ◆ Metal fragments, fibers, grease (except as specified in the usage rules), dust, other impurities, foreign objects, and contaminants must not adhere to or remain on the surfaces of the parts or within their cavities