1. Test the sealing performance of the valve to ensure its performance.  

2. Check whether the sealing surface of the valve is worn, and repair or replace it according to the situation.  

3. The valve storage environment should be kept in a dry and ventilated room and blocked at both ends of the channel.  

4. The valve installed and used should be regularly checked to ensure its normal operation.  

5. The valve in operation shall be in good condition. The bolts on the flange and the bracket are complete, the threads are not damaged, and there is no looseness.  

6. Check the trapezoidal thread wear condition of stem and stem nut, whether the packing is outdated and invalid, etc., and make necessary replacement.  

7. If the valve is in a harsh environment, it is easy to be contaminated by rain, snow, dust, sand and other dirt, and the valve should be installed with a protective cover.