The electric valve with electric actuator control valve, enabling the valve on and off. Which can be divided into two parts, the upper part of the electric actuator, the lower half is divided into the valve. Electric valves are two, one for the rotary electric valve: the rotary electric actuator with rotary valves used to achieve the control valve 90 degrees or less spin off the fluid conduit; another way for the electric valve straight trip: From straight stroke electric actuator with straight travel valve used to achieve control pipe valve plate under the action of fluid off. Usually in the higher degree of automation equipment supporting the use.
The operation of the electric valves, all valves should be complete and intact. Flanged threaded and bracket bolts indispensable thread should be intact, does not allow loosening. Hand tighten the nut on the wheel, if found loose should be tightened to prevent wear and tear or lost connection handwheel and plate. If the handwheel is lost and does not allow wrench instead should be fully serviced. Gland not skew or no pretension gap. For vulnerable rain, snow, dust, sand and dirt contamination of the environment of the
electric valve, the valve stem to install protective cover. Electric valves on the gauge should be kept complete, accurate and clear. Electric valve seals, caps, pneumatic accessories, etc. should be complete and intact. Insulation jacket should be no dents, cracks.
Valve electric device is programmed to achieve valves, automation, and remote indispensable equipment, its movement can be stroke, torque or axial thrust to control the size. Since valve
electric device operating characteristics and utilization depends on the type of valves, fittings and valves in the pipeline job specification or equipment on location, therefore, the correct choice valve electric device for preventing overload phenomenon (operating torque than the control torque) is essential. Typically, the correct choice of valve actuators based on the following: Operating torque: operating torque is to select the most important parameters of valve actuators, electric device output torque valve operation should be the maximum torque of 1.2 to 1.5 times.
Valve electric actuator output shaft rotation number of laps and the valve nominal diameter,
stem pitch, the first few threads about, according to M = H / ZS calculated (M is the total electric device should satisfy rotation number, H is the valve opening height, S is stem transmission thread pitch, Z for the first few stem threads).
Classes for the next shot multi-turn valves, if the electric device allows the maximum stem diameter can not be dispensed through the valve stem, it can not be assembled into electric valve. Therefore, the electric unit hollow output shaft next shot must be greater than the inside diameter of the valve stem diameter. On the part of the rotary valve and rotary valve stem valves in the dark, though without considering stem diameter, but should also take full account of the matching stem diameter and keyway dimensions, so that assembly can work.
