1. The manual valve is the most widely used valve. Its hand wheel or handle is designed according to ordinary manpower, taking into account the strength of the sealing surface and the necessary closing force. Therefore, you cannot use a long lever or a long wrench to move. Some people are accustomed to using wrenches, and they should be careful not to use too much force, otherwise it will easily damage the sealing surface, or break the handwheel and handle.

2. When opening and closing the valve, the force should be steady without impact. Some parts of high-pressure valves with impact opening and closing have considered that this impact force cannot be equal to that of general valves.

3. For the steam valve, before opening, it should be pre-heated and the condensed water should be removed. When opening, it should be as slow as possible to avoid water hammer.

4. When the valve is fully opened, the handwheel should be turned upside down to make the threads tightly to avoid loosening and damage. For rising stem valves, remember the valve stem positions when fully open and fully closed to avoid hitting the top dead center when fully open. And it is convenient to check whether it is normal when fully closed. If the valve stem falls off, or large debris is embedded between the valve core seal, the position of the valve stem will change when it is fully closed.

5. When the pipeline is first used, there are a lot of internal dirt. You can open the valve slightly, use the high-speed flow of the medium to wash it away, and then close it gently (not fast or violently to prevent residual impurities from damaging the sealing surface), turn it on again, repeat this many times, flush out the dirt, and then put it into normal work.

6. For a normally open valve, there may be dirt on the sealing surface. When it is closed, use the above-mentioned method to flush it clean, and then formally close it tightly.