1.Manual valve operation requires the operator to hold the handle or hand wheel for operation. The valve cannot be opened and closed with the help of lever and long wrench to avoid damage to the handle or hand wheel caused by excessive force. Furthermore, it cannot be operated violently to avoid accidents.
2.Hand gate and hand globe valves are operated by hand wheel. After the valve is fully opened or closed, turn 1/4 to 1/2 turn to allow better sealing between threads and avoid damage to the valve due to over-tightening.
3.Operate the manual steam valve, preheat the pipe before opening, and remove the condensed water from the pipe. Open the valve slowly to prevent damage to the valve and piping equipment caused by water rushing.
4.Impurities and dirt are easily attached to the sealing surface of the valve, which is often in the open state. Before closing, slightly open a slit to allow the high-speed flowing medium to wash away foreign objects, and then gently close to improve the sealing effect of the valve.
5.In some pipelines of overly high temperature medium, the temperature inside the valve body drops after the manual valve is closed. As the heat expands and contracts, the valve piece shrinks. There will be some small cracks in the sealing surface and the valve will leak.In this case, close the manual valve again after closing it.