Basic Knowledge And Maintenance Skills Of Ball Valves

The ball valve is a valve with a ball as the opening and closing part. With the rapid development of our domestic processing technology, detection technology and intelligent control technology, as well as the continuous emergence of various new sealing materials, ball valve products will be more and more widely used. At present, ball valve products are not only used in general industrial pipelines, but also widely used in coal-to-liquid projects, nuclear industry, and aerospace industry pipelines. [Wenzhou Keda Valve] takes you to learn more about ball valves.

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Basic knowledge of ball valve

Classification of ball valves. There are many structural forms and varieties of ball valves, and new products and new structures are still emerging. According to the characteristics and uses of ball valves, ball valves can be divided into several types. According to the support method, such as floating ball valve and fixed ball valve, the main feature of floating ball valve is that the ball has no supporting shaft, the ball is supported by the valve seat at both ends of the valve inlet and outlet, and the valve stem and the ball are movably connected. The ball of this kind of ball valve is clamped by the two valve seats and presents a "floating state". The sphere of the fixed ball valve is integrated with the upper and lower valve stems, or made into an integral shaft-connected ball. The sphere and the upper and lower valve stems are welded into one piece. On the bearing, the sphere can be free along the axis perpendicular to the valve channel. Rotate, but not move along the channel axis. Therefore, when the fixed ball valve is working, the force generated by the fluid pressure in front of the valve on the ball is all transmitted to the bearing, and the back seat of the valve will not move, so the valve seat will not bear excessive pressure, which is more suitable for high pressure and large diameter. occasion. Ball valves can also be classified according to installation method, spherical structure classification and so on.

Ball valve maintenance skills

1. First check whether the pressure of the upstream and downstream pipelines of the ball valve has been relieved, and then proceed to the disassembly and decomposition operation after confirmation.

2. To prevent damage to the sealing surface of parts, especially non-metallic parts, special tools should be used when removing the o-ring

3. When assembling the bolts on the flange, they must be tightened symmetrically and evenly

4. The cleaning agent should be compatible with the rubber parts, plastic parts, metal parts and working medium in the ball valve. For example, when the working medium is gas, gasoline can be used to clean metal parts, and non-metal parts can be cleaned with pure water or alcohol.

5. The decomposed single parts can be cleaned by dipping, and the metal parts can be scrubbed with a clean cloth with detergent

6. After cleaning, it is necessary to wait for the cleaning agent on the wall to be washed before assembling, but it cannot be put on hold for a long time, otherwise it will rust and be polluted by dust.

7. The grease used should be compatible with the ball valve metal material, rubber parts, plastic parts, and working medium. The working medium is gas, for example, special 221 grease can be used.

8. Metal chips, fibers, grease dust and other impurities and foreign matter are not allowed to contaminate or adhere to the surface of the parts during assembly.

When the final installation is completed, the ball valve is switched on and off several times. If it is flexible and has no stagnation, it proves that it is working properly. Then check the sealing performance of the flange joint surface of the pipeline and the ball valve according to the design requirements of the pipeline. If possible, after the piping is installed, the sealing pressure and performance of the ball valve can be tested according to the standard.