Q. QR, QV type throttle valve
Work pressure Pmax=315 bar
Traffic Qmax=120Ipm
1. Overview
SE2 and SEH2, as well as SE3 and SEH3 proportional speed control valves, are used for stepless remote control of the working speed of hydraulic actuators independent of pressure
They can make the actual flow rate of the actuator change proportionally to an electrical signal (control current) within the adjustment range according to demand, involving manual remote control adjustment of working speed, achieving simple acceleration and deceleration, until the pre selected speed in the automatic working cycle
The control of these valves is achieved through a proportional amplifier that can maintain a constant current,
For the simplest cases (such as pump on/off), control can be achieved through a potentiometer connected in series with the proportional magnetic field
The main functional components of these pressure compensated speed control valves are proportional electromagnets, flow measurement holes, and flow controllers. The proportional electromagnets adjust the flow measurement holes of their overcurrent section to generate a small pressure drop required for the flow controller function
It has the following different genotypes;
SE type direct acting flow hole
The biggest advantage is that the minimum control flow rate Qmin is close to O, but the large motion mass limits its response time
SHE type with pilot flow hole
The advantage is fast dynamic control and short response time, but due to oil leakage in the pilot control circuit, a minimum flow rate is required
Two types are available; Two way or three-way speed regulating valve
Single valve structures can be divided into tubular connections or plate connections
Additional functions (three-way valve); Pressure limiting valves are used to limit load pressure, any unloading cycle, etc
Additional functions (two-way valve); Bypass one-way valve, a bridge circuit composed of one-way valves for any flow direction
PB type proportional throttle valve
Used for systems that do not require safety and load independent speed control (such as acceleration and deceleration) and limiting flow
Can provide two structural forms of flow measurement holes
When powered on (in shutdown state), the current measuring hole is fully open, which means that there is all the load flow at interface A. Increasing the control current to the proportional electromagnet gradually reduces the load flow to the minimum value
When there is no power (shutdown state), the current measuring hole is closed, which means that as the control current of the proportional electromagnet increases, the minimum load flow at point A gradually increases until it reaches its maximum value
