The working principle and technical parameters of the electric double-seat control valve
The electric double-seat control valve is an indispensable and important component in the industrial automation control system, which is widely used in various processes to realize the regulation and control of the flow, pressure, temperature and other parameters of the fluid medium. This article will focus on the working principle, technical parameters and selection methods of electric double-seat control valves, to help readers better understand and choose the control valve suitable for their process needs.
1. The working principle of the electric double-seat control valve
The electric double-seat control valve is composed of main components such as valve body, valve plate (or valve cage), valve shaft, and electric actuator. Its working principle is to drive the valve shaft to rotate through the electric actuator, and then drive the valve plate (or valve cage) to move up and down inside the valve body to realize the regulation and control of the fluid medium. According to the process requirements, the electric double-seat control valve can adopt different valve plate (or valve cage) structure forms, such as single-seat, double-seat, cage, etc.
Second, the technical parameters of the electric double-seat control valve
1. Flow regulation range
The flow regulation range refers to the range between the minimum and maximum flow rates that can meet the process requirements under normal operating conditions. When selecting a control valve, it is necessary to determine the appropriate flow adjustment range according to the actual process needs.
2. Working pressure
The working pressure refers to the pressure of the fluid medium on the valve body under the normal working condition of the regulating valve. Depending on the process requirements, the working pressure of the control valve will be different, so it is very important to choose the appropriate pressure level to ensure the normal operation of the control valve.
3. Temperature range
The temperature range refers to the range between the minimum and maximum temperatures at which the control valve can meet the process requirements under normal operating conditions. When selecting a control valve, it is necessary to determine the appropriate temperature range according to the actual process needs.
4. Leakage
The amount of leakage refers to the amount of fluid that the control valve allows the fluid medium to pass through when it is closed. The amount of leakage directly affects the performance of the control valve and the accuracy of the process control. In general, the smaller the leakage, the better the performance of the control valve.
5. Drive power supply and input signal
The electric double-seat control valve needs to be equipped with an electric actuator, and the driving power supply and input signal refer to the power supply voltage supplied to the electric actuator and the type of control signal received. The common power supply voltage is 220VAC, 24VDC, etc., and the control signal has two types: analog signal and digital signal.
3. Selection method of electric double-seat control valve
1. Determine the type of control valve according to the process requirements
When selecting a control valve, it is necessary to determine the appropriate type according to the actual process needs. For example, a single-seat control valve can be selected for applications requiring high flow regulation, and a cage control valve can be selected for applications requiring high-precision control.
2. Determine the main technical parameters of the control valve
According to the process requirements and the actual situation, determine the main technical parameters of the control valve, such as flow adjustment range, working pressure, temperature range, leakage amount, etc. These parameters will directly affect the performance and use of the control valve.
3. Consider the material and anti-corrosion performance of the control valve
According to the nature and corrosiveness of the fluid medium, select the appropriate material of the control valve to ensure its anti-corrosion performance and service life. For example, for corrosive fluid media such as strong acids and alkalis, corrosion-resistant stainless steel can be selected.
4. Consider the ease of installation and maintenance of the control valve
When choosing a control valve, you also need to consider its ease of installation and maintenance. Choosing a control valve that is easy to install and maintain can reduce operating costs and increase productivity.
To sum up, this article introduces the working principle, technical parameters and selection method of electric double-seat control valve. In practical application, it is necessary to comprehensively consider the above factors according to the process requirements and the actual situation, and choose the electric double-seat control valve that suits your needs. At the same time, in order to ensure the normal operation and use of the control valve, it is also necessary to strengthen the attention and management of its maintenance and maintenance work.