Three Control Methods Of Hydraulic Valve

  Three control methods of hydraulic valve

  Hydraulic valve is a pressure oil operation of the automation components, which is controlled by the pressure valve oil pressure, usually combined with the use of electromagnetic pressure valve can be used for long-distance control of hydropower station oil, gas, water pipe system off. Commonly used in clamping, control, lubrication and other oil. Hydraulic valve in accordance with the control mode can be divided into direction control, pressure control, flow control three categories.

  Directional control of hydraulic valves

  Directional control The hydraulic valve is divided into one-way valve and directional control valve according to its application.

  Check valve: only allows the fluid in the pipeline in one direction, reverse that cut off.

  Directional valve: hydraulic valve change the relationship between the different pipe between the break.

  According to the number of channels controlled by the two-way, three-way, four-way, five-way, etc .; according to the spool drive way manual, mobile , Electric, hydraulic and so on.

  In the late 1960s, electro-hydraulic proportional control valves were developed on the basis of several hydraulic control valves. Its output (pressure, flow) can be continuously changed with the input electrical signal. Electro-hydraulic proportional control valve according to the role of different, correspondingly divided into electro-hydraulic proportional pressure control valve, electro-hydraulic proportional flow control valve and electro-hydraulic proportional directional control valve.

  Pressure control hydraulic valve

  According to the use of overflow valve, pressure relief valve and sequence valve.

  Relief valve: can control the hydraulic system to maintain a constant state when the set pressure is reached. A relief valve for overload protection is called a safety valve. When the system fails, the pressure rises to the limit may cause damage, hydraulic valve the valve port will open and overflow, to ensure the safety of the system.

  Pressure relief valve: can control the branch circuit to get lower than the main circuit pressure pressure. Decompression valve according to its control of the pressure function is different, but also divided into the value of the pressure relief valve (output pressure is constant) ﹑ differential pressure valve (input and output pressure difference is set) and the ratio of pressure reducing valve (The input and output pressure to maintain a certain ratio).

  Sequential valve: can make an implementation of components (such as hydraulic cylinders, hydraulic motors, etc.) after the action, and then in order to make other executive elements. The pressure generated by the pump first to promote the movement of the hydraulic cylinder 1, while the inlet valve through the sequence of action on the area A, when the hydraulic cylinder 1 after the movement is complete, the pressure increases, the role of the upward thrust in the area A greater than the spring Value, the spool up so that the inlet and outlet port connected to the hydraulic cylinder 2 movement.

  Flow control hydraulic valve

  The flow rate is adjusted by adjusting the area of the orifice between the valve plug and the valve body and the local resistance it produces to control the speed of movement of the actuator. Flow control hydraulic valve according to the use of five kinds.

  Throttle: After adjusting the orifice area, hydraulic valve the moving speed of the actuator with little change in load pressure and less uniformity of movement is basically maintained.

  Speed regulating valve: in the load pressure changes can keep the throttle inlet and outlet pressure difference for the set value. In this way, after the throttle area is set, regardless of how the load pressure changes, the governor can keep the flow through the throttle constant, thus stabilizing the speed of the actuator.

  Diverter valve: regardless of the size of the load, hydraulic valve can make the same oil source of the two actuators are equal flow equal to the diversion valve or synchronous valve; get proportional distribution of the proportion of the diversion valve.

  The output valve is operated in proportion to the diverter valve so that the flow into the manifold is proportionally distributed.

  Shunt flow valve: hydraulic valve both flow distribution valve and the two functions of the collector.