Views: 0 Author: Site Editor Publish Time: 2025-09-30 Origin: Site
As a key component in the hydraulic system, the superimposed hydraulic control check valve has attracted much attention. The following is a detailed analysis of this hydraulic component:
Working principle of superimposed hydraulic control check valve
Although the core working principle of the superimposed hydraulic control check valve is similar to that of conventional hydraulic valves, it is the same in structural design and connection size, forming a standardized series. It not only has the control function of traditional hydraulic components, but also plays the role of oil passage. The layout of the main oil passage and bolt connection holes of each diameter series are consistent with the reversing valves of the same specifications, thus supporting flexible superposition and building a hydraulic control system with diverse functions.
The valve is mainly composed of a solid steel valve body, one or two check valves, a pilot stage piston and a pilot cone valve spool embedded in the main valve spool of the check valve. When the oil flows from port A1 to port A2, the check valve (2) opens, and at the same time pushes the pilot piston (4) to the right position, and through the action of the pilot cone valve core (5), the check valve (3) also opens. Once the oil inlets A1 and B1 are out of pressure, the spring force presses the valve core tightly on the valve seat, cutting off the oil path between the check valve and the actuator. To ensure that the conical valve accurately closes the valve port, a Y-type functional reversing valve is required to make the piston (4) in the middle, and the oil ports A1 and B1 are connected to the oil tank.
Typical application scenarios of superimposed hydraulically controlled check valves
Hydraulic cylinder support function: In vertical hydraulic cylinders, leakage of the slide valve and pipeline may cause the piston and piston rod to slide down. By connecting the hydraulic control check valve into the oil circuit in the lower chamber of the hydraulic cylinder, the moving part can be effectively prevented from sliding down and ensure the stability of the system.
Pressure maintenance: The slide valve reversing valve has gap leakage and the pressure holding time is limited. For situations where pressure is required for a long time, a hydraulically controlled check valve can be added to the oil circuit to utilize the tight closing characteristics of the cone valve to achieve long-term pressure holding of the oil circuit.
Hydraulic cylinder locking: When the reversing valve is in the middle position, the two hydraulically controlled check valves are closed, tightly sealing the oil in both chambers of the hydraulic cylinder to prevent the piston from moving due to external force, and realize reliable locking of the hydraulic cylinder.
Optimization of large flow oil discharge: When the hydraulic cylinder piston is returned, if the effective working area of the two chambers is large, the oil discharge volume of the right chamber will increase sharply. Using a small flow spool valve may cause throttling and limiting the piston's backward speed. After adding a hydraulically controlled check valve, the pressure oil can open the check valve and smoothly discharge the oil in the right chamber to improve the system efficiency.
Oil filling valve application: When the vertical hydraulic cylinder piston drops at high speed, it may cause air suction and negative pressure due to the action of high-pressure oil and self-weight. At this time, the hydraulically controlled check valve can be used as an oil filling valve to complete the oil filling function and ensure the normal operation of the system.
Combined into a reversing valve: When designing a hydraulic circuit, a hydraulically controlled check valve can be combined into a reversing valve. For example, connecting two hydraulically controlled check valves with one check valve in parallel (the check valve is centered) can create a reversing circuit equivalent to a three-way three-way exchange valve. However, it should be noted that when the control pressure oil port is not working, it should be opened to the oil tank to ensure the control piston reset and the reverse cutoff of the liquid flow of the check valve.
Unique advantages of superimposed hydraulically controlled check valves
Compact structure and small size: The hydraulic system designed with superimposed valves is more compact, with a significantly reduced volume and weight.
Easy to install and short cycle: The installation process of the superimposed valve hydraulic system is simple and fast, and the assembly cycle is significantly shortened.
Flexible assembly and strong adaptability: When the working conditions of the hydraulic system change and components need to be added or decreased, the assembly process of the superimposed hydraulic control check valve is both convenient and fast.
Pipeless connection to reduce leakage: pipeless connection between components effectively eliminates leakage, vibration and noise problems caused by oil pipes, pipe fittings, etc.
Flexible configuration and convenient maintenance: the entire system is flexible and changeable, with a uniform appearance, making maintenance work easier and simple.
High degree of standardization: Superimposed hydraulic control check valves have a high degree of standardization, universalization and integration, which is easy to select and replace.
