A control valve vibration, fault phenomenon and the reasons are as follows:
1. Regulating valve in He Kaidu under vibration, (1) support instability; (2) there is vibration source near; (3) the valve core and bushing wear serious,
2. The regulating valve full close position near the end of the vibration, (1) regulator is chosen, often used in the small open degrees; (2) the flow direction of medium single-seat valve and closed in the opposite direction,

Two, control valve action is slow, slow phenomenon and the reason is as follows:
1. The valve stem in one direction only moves slow, pneumatic diaphragm actuator of the diaphragm leakage; (2) the "O" type seal leakage in the actuator,
2. Stem in reciprocating movements were slow phenomenon, (1) the body with sticky content block; (2) a asbestos packing ptfe or graphite packing metamorphic sclerosis lubricating oil dry; (3) packing too tight, the friction resistance increases; (4) frictional resistance due to the valve stem is not straight; 5. No locator pneumatic regulator can also lead to action is slow,

Three, regulating valve leakage increase, the reasons for the leak of the following:
1. Valve leakage when fitted, (1) the valve core is wear and tear, severe leakage, (2) valve is not adjusted the closed lax,
2. The short of full closed position, (1) medium pressure difference is too big, small rigidity, actuator valve closed lax; (2) valve with foreign body; (3) bushing sintering,

Four, smaller flow adjustable range, the main reason is that the valve core is corroded smaller, so that the minimum flow of adjustable,