Add: Mechanical&Electrical Industry Zone,Yuhuan,Zhejiang,China
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. There are direct and pilot type of the points, multi-use pilot type.
Used to reduce and stabilize the system in a branch of the oil pressure, commonly used in clamping, control, lubrication and other oil. Direct-type, pilot type, superposition of the points.
A component used in a hydraulic drive to control liquid pressure, flow, and direction. One of the control pressure is called the pressure control valve, the control flow called the flow control valve, control through the ﹑ off and flow direction called the direction control valve.
According to the use of overflow valve, pressure relief valve and sequence valve. ⑴ relief valve: to control the hydraulic system to achieve the set pressure to maintain a constant state. A relief valve for overload protection is called a safety valve. When the system fails, the pressure rises to the limit may cause damage, the valve port will open and overflow, to ensure the safety of the system. ⑵ pressure reducing valve: can control the branch circuit to get lower than the main circuit pressure and low 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). ⑶ sequence valve: can make an implementation of components (such as hydraulic cylinders, hydraulic motors, etc.) after the action, and then in order to make other elements of the action. 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.
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 valves are divided into five types. ⑴ throttle valve: in the adjustment of the orifice area, can make the load pressure is not changed and the movement uniformity of the implementation of the component is not high speed basically stable. ⑵ speed control valve: the load pressure changes can keep the throttle valve inlet and outlet pressure for the fixed 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. ⑶ diverter valve: regardless of the size of the load, 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 flow distribution valve. ⑷ collector valve: the role of the opposite with the diversion valve, so that the flow into the flow of the proportional distribution of the valve. ⑸ shunt flow valve: both flow distribution valve and two functions.
According to the use of one-way valve and valve. Check valve: only allows the fluid in the pipeline in one direction, reverse that cut off. Directional valve: change the relationship between the different pipe between the break. According to the number of the control of the number of channels in two, three, four, five, etc.; according to the spool drive way manual, mobile, electric , Hydraulic and so on. Figure 2 for the three four-way valve works. P is the oil supply port, O is the return port, and A and B are the output ports leading to the actuator. When the spool is in the middle position, all the port cut off, the implementation of the component does not move; when the spool moved to the right position, P and A, B and O through; when the spool to the left position, P and B Pass, A and O pass. In this way, the actuator can be positive and reverse movement.
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.