Views: 201 Author: Site Editor Publish Time: 2021-05-06 Origin: Site
Since the electric actuated butterfly valve is a combination of a butterfly valve and an electric actuator, how to correctly select the electric actuator after the electric butterfly valve is determined is an important factor related to whether the engineering needs can be satisfied in practice. When selecting an electrically operated butterfly valve, not only the aforementioned working environment, electrical control and general technical functions should be considered, but also the generalized technical functions of the electric butterfly valve equipment should be fully considered.
Electric actuators mainly include electric servo actuator, electromagnetic valve actuator, electric rotary actuator, and so on. The electric actuator has convenient energy access and rapid signal transmission, but the structure is complex and the explosion-proof performance is poor.
The baffle of the butterfly valve controls the flow of fluid with the rotation of the shaft. It is composed of valve body, baffle, baffle shaft and shaft seal. Its simple structure, small volume, light weight, low cost and large flow capacity are especially suitable for the occasions of low pressure difference, large diameter, large flow gas and fluid with suspended solids, but the leakage is large. High performance butterfly valves are not only widely used in oil, gas, chemical, water treatment and other general industries, but also used in cooling water systems of thermal power stations.
When selecting a butterfly valve motorized actuator for a lifting stem valve, pay attention to the value of the stem diameter that it is allowed to pass, and the stem diameter must be smaller than this value. In addition, with regard to multi-reversal electric equipment, the height of the valve stem cover (related to the valve diameter) should also be proposed when selecting. Rotary stem valves can be equipped without stem cover.
The connection type and standard of the valve and the electric equipment should conform to the national standard: GB/T12222-1989 connection of multi-reverse butterfly valve drive equipment, GB/T12223-1989 connection of partial reversal butterfly valve drive equipment.
Output Torque and Speed of Electric Equipment
The output torque value is one of the important technical parameters of electric equipment, and it is also an important parameter that needs to be selected in the application. It is undesirable if the output torque of the electric equipment selected when combining motor operated butterfly valve and solenoid butterfly valve is too large or lacking.
Due to general conditions, electric equipment manufacturers need to test and adjust the output torque value when the product leaves the factory, which is relatively accurate. If the output torque margin is too large, the electric valve will have great potential danger. Once the failure of control and maintenance occurs, it will be very easy to cause valve damage (stem twists, valve body rupture), and it is very easy to cause pipeline system accidents. Therefore, it is not advisable to choose too large output torque margin. If the valve cannot be opened in practice, it is also attributed to unreasonable selection.
