Teach you to choose an electric actuator for the valve
The valve electric device is an indispensable driving device for realizing valve program control, automatic control and remote control. The movement process can be controlled by the stroke, torque or axial thrust. So how can we choose a suitable valve electric device? From the point of view of sales, what parameters do we need to determine which valve electric device the customer needs? The following is a small series to explain in detail:
Of course, the easiest thing is that the customer directly provides the model of the valve electric device, which is the easiest to determine, but there is a problem here. There are many models of the valve electric device on the market, which also causes some troubles for the comparison between the products. If there is no model of the valve electric device, then take the following steps:
According to the operation mode of the valve electric device, it can be divided into a multi-turn electric device, a partial-turn electric device, a straight-stroke electric device, and a quarter-turn electric device.
For example, gate valves, globe valves, etc. need to be turned many times to realize the opening or closing of the valves, so they are multi-turn valves, and such valves require multi-turn electric devices.
For example, butterfly valves, ball valves, etc. only need to be rotated 90° to open or close the valve, so they are partial-rotation valves, which need to be equipped with partial rotary electric devices.
For example, single-seat valves, double-seat valves, sleeve valves, etc. are straight-stroke valves, that is, valves that normally reciprocate in a straight line (including movement in a spiral manner) require a linear actuator.
For example, a flapper door, a gate, etc., which have a fixed rotating shaft and need to be rotated from 0° to 90°, require a quarter-turn electric actuator.
The first type: ordinary electric device This type of electric device has a simple dial to display the switch of the valve, and the external control requires the electric control box, which is the most basic model.
The second category; mechatronics electric devices. Such electric devices come with a control box, so-called electromechanical integration. With liquid crystal display, it can feedback 4~20mA standard signal, which can determine the full open, full off, and uncertain intermediate position of the valve, that is, the switch quantity control.
The third category: the adjustment type electric device, the difference from the electromechanical integration electric device is the difference of the control mode; the analog quantity control can receive and feedback the 4~20mA standard signal, so that the precise adjustment of the valve can be realized, and the valve can be determined Fully open, fully closed and precise intermediate position.
For multi-turn electric devices, partial rotary electric devices, and angular-stroke electric actuators, the most important parameter is torque, the unit is N.m. The opening or closing of the valve requires a torque to act on it. If the torque is small, it may result in failure to close and not open.
The most important parameter for a straight-stroke electric actuator is the force in N. If the force is small, the valve will not open or close. Therefore, in the process of electric device selection, follow one of the simplest principles: Ning can be large, not small.
Generally divided into whether remote control is required (adding non-invasive modules), whether explosion protection is required, etc.
Such as the voltage used, valve opening and closing time, etc.
Through the above five steps, I believe you can choose a suitable valve electric device.
Whether you have any questions about valve electric actuators, please feel free to contact us.