1 The role of self-regulating valve
Self-regulating valve are the use of valve output feedback signal (pressure,temperature) through the signal tube to the actuator-driven valve to change the valve opening, to regulate the pressure, flow, temperature purposes.
2 Self-regulating valve advantages
Self-regulating valve is a new type of self-regulating valve. Relative to the manual control valve, it has the advantage of being able to automatically adjust; relative to the electric control valve, its advantage is that no external power. Application practice shows that in the closed water circulation system (such as hot water heating system, air conditioning chilled water system), the correct use of such valves, can easily achieve the system flow distribution; can achieve dynamic balance system; can greatly simplify the system Of the commissioning work; can stabilize the working state of the pump.
Classification of Self - operated Regulating Valves
Self-regulating valve is divided into two kinds of direct action and indirect action:
1) Direct acting regulating valve
Direct-acting regulating valve, also known as spring-loaded control valve, its structure has elastic components: such as springs, bellows, bellows-type temperature package, the use of elastic force and feedback signal balance principle.
2) Indirect acting regulating valve
Indirect effect of the control valve, an increase of a pilot (pilot valve) it plays a role in the amplification of the feedback signal and then through the implementing agencies to drive the main valve valve movement to change the valve opening purposes.
If the pressure control valve, the feedback signal is the valve outlet pressure, through the signal tube into the implementing agencies.
If the flow control valve, the valve at the exit there is an orifice plate (or other resistance devices) from the orifice plate out of the differential pressure signal into the implementing agencies.
If the temperature control valve, the valve outlet there is temperature sensor (or temperature package) through the temperature sensor thermal expansion and contraction of the medium drive actuators.
4 self-regulating valve characteristics
Self-regulating valve without external energy, can work without electricity in the air, convenient and save energy. Pressure segmentation range of fine and cross-cutting, high precision adjustment. The pressure set point can be set continuously during operation. On the valve after the pressure adjustment, the pressure before the valve and the valve after the pressure ratio of 10: 1 to 10: 8. Rubber diaphragm detection, the implementing agencies to measure high precision, action sensitive. Using pressure balance mechanism, the control valve responsive, precise control.