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Manual valve is a valve operated by handle and handwheel. It is a common valve used in equipment pipeline.Its handle, hand wheel rotation direction clockwise is closed, counterclockwise is open.However, there are individual valves that open in the opposite way.Therefore, attention should be paid to check the open and close mark before operation.。

The handwheel and handle on the valve are designed according to normal manpower. Therefore, in the use of the valve, the operator is not allowed to open or close the valve with the help of a lever and a long wrench.Handwheel, handle diameter (length) 320mm handwheel, allow two people to operate together, or allow one person to use the appropriate lever (generally not more than 0.
5m long) to operate the valve.

Gate valves and globe valves, close or open the head (that is, the bottom dead point or the top dead point) to turn 1/4 ~ 1/2 laps, so that the thread is better close, advantageous operation, so as not to get too tight, damage the valve parts.

Some operators are used to using levers and long wrenches to operate, and think that the greater the closing force, the better, but it is not.This can cause premature valve damage and even cause an accident.