Pressure reducing valve are valves that automatically stabilize the outlet pressure by adjusting the inlet pressure to a desired outlet pressure and relying on the energy of the medium itself. From the point of view of hydrodynamics, the water pressure reducing valve is a throttling element with local resistance varying. In other words, by changing the throttling area, the flow rate and the kinetic energy of the fluid will change, resulting in different pressure losses, so as to achieve the purpose of reducing pressure. Then, by means of the control and adjustment system, the fluctuation of the pressure behind the valve is balanced with the spring force, and the pressure behind the valve remains constant within a certain error range.
(1) Pressure regulation range: It refers to the adjustable range of the pressure reducing valve output pressure p2, within which the specified accuracy is required. The pressure regulation range is mainly related to the stiffness of the pressure regulating spring.
(2) Pressure characteristics: It refers to the characteristic that the output pressure fluctuates due to input pressure fluctuation when the flow rate g is constant. The smaller the output pressure fluctuation, the better the characteristics of the pressure reducing valve. The output pressure must be lower than the input pressure—the set value does not substantially change with the input pressure.
(3) Flow characteristics: It refers to the input pressure-timing, and the output pressure changes with the change of the output flow g. When the flow rate g changes, the smaller the change in the output pressure, the better. Generally, the lower the output pressure, the smaller the fluctuation with the output flow.