Self-regulating valve basics overview

Since the self-operated regulator valve does not require other external energy sources such as power supply and gas source, it is driven by the energy of the medium alone. It is energy-saving, environmentally-friendly, and easy to use. After the installation, the pressure value can be set to automatically run, so the The requirements for low control accuracy and lack of power supply and air supply have been used more and more widely. However, in the use of the process, we must pay attention to the particularity of the type selection, otherwise it will easily lead to accidents. During use, attention should be paid to the type selection and installation environment used. Therefore, it is very important to understand in detail the working principle and structure of the self-regulating valve.

First, the structure and working principle of self-regulating valve

The pre-valve pressure P1 of the process medium is throttled by the valve core and valve seat, and then becomes pressure P2 after the valve. The post-valve pressure P2 acts on the top plate via the lower membrane chamber of the control line input actuator. The resulting force balances the reaction force of the spring. Determines the relative position of the valve plug and valve seat and controls the pressure behind the valve. When the pressure P2 increases after the valve, the force acting on the top plate with the pressure P2 of the valve also increases. At this time, the force of the top plate is greater than the reaction force of the spring, so that the valve core is closed to the position of the valve seat until the force of the top plate counterbalances with the spring reaction force. At this time, the flow area between the valve plug and the valve seat is reduced, and the flow resistance becomes larger, so that the pressure P2 of the valve is reduced to a set value. Similarly, when the pressure P2 decreases, the direction of action is opposite to the above, which is the working principle of the pressure adjustment after the valve. When it is necessary to change the setting value of the pressure P2 after the valve, the adjustment nut can be adjusted.

Second, the technical characteristics of self-regulating valve

The self-regulating valve is an actuator product that does not need any external energy and uses the self-energy of the controlled medium to achieve automatic adjustment. It integrates detection, control, and execution of all functions into one independent instrument control system. The biggest feature of this product is that it can work in a place without electricity and air, and at the same time saves energy. The pressure setting value can be adjusted freely during operation. Applicable to explosive dangerous environment; simple structure, small maintenance workload, can be realized unattended; integrates the functions of transmitter, controller and implementing agency, low cost, saving project investment. With the quick opening flow feature, quick action and good sealing performance, it is widely used in various industrial equipment such as petroleum, chemical industry, electric power, metallurgy, food, light textile, machinery manufacturing and residential buildings and other gases and liquids. Steam medium decompression, voltage regulation (for valve adjustment), or pressure relief, pressure control (for valve pre-regulation) automatic control. The attached condenser can be used at a temperature of ≤350°C.

Third, the type of self-regulating valve

There are many types of self-operated regulating valves, which can be divided into self-operated pressure (differential pressure) regulating valves, self-operating liquid level regulating valves, self-operated temperature regulating valves and self-operating flow regulating valves according to controlled parameters.

Fourth, the use of self-regulating valve and the scope of application

The self-regulating valve is an energy-saving product that automatically adjusts the pressure without relying on external energy and only relying on the pressure change of the regulating medium itself. It has a comprehensive function of measurement, execution, and control. Widely used in petroleum, chemical, metallurgy, light industry and other industrial sectors and urban heating, feeding system. In the oil industry has been widely used, especially in the oil field remote sites. It can also be used for non-corrosive (up to 350°C) pressure control devices for liquids, gases, and steam.