What are the characteristics of superimposed relief valves

As the core component of modern hydraulic systems, the superimposed relief valve can be analyzed from three dimensions: structural design, functional performance, and application advantages. The specific details are as follows:

1. Structural design: modular and standardized integration

Overlay installation

The valve body is designed as a flat plate structure, with standard oil port connection surfaces (such as cavity holes that comply with ISO 4401 standards) on both sides, and is directly superimposed on the bottom of the direction control valve, the surface of the main oil block or the top of another superimposed valve, without additional piping connections.

Advantages: Save space (the installation volume is reduced by more than 60% compared to traditional split valves), simplify the layout of hydraulic circuits, and make the system more compact and tidy.

Built-in oil circuit

The oil flows through the cast or drilling channels inside the valve plate, eliminating external pipe connections.

Advantages: Reduce leakage caused by pipe fittings and joints (statistics show that pipe fitting leakage accounts for 35% of hydraulic failures), vibration and noise, and improve system reliability.

Standardization and universality

The International Organization for Standardization (ISO) has formulated standards for connecting dimensions and height dimensions (such as ISO 7790, ISO 4401), and superimposed valves of the same diameter (such as NG02, NG06, NG10, etc.) can be used interchangeably.

Advantages: It is convenient for system expansion or modification, and only requires adding or decreasing the valve module to adjust the function, no need to re-pipe, shortening the assembly cycle.

2. Functional performance: accurate control and safety protection

Pressure regulation function

Fixed pressure overflow: In the throttling control system of the quantitative pump, when the system pressure exceeds the set value, the overflow valve is opened and the excess flow overflows back to the oil tank to ensure constant inlet pressure (such as the injection mold cavity pressure control).

Voltage stabilization: When connected in series on the oil return circuit, back pressure can be generated, increasing the stability of moving parts (such as machine tool hydraulic system).

System unloading: Connect a small flow solenoid valve in series at the remote control port. When the solenoid is powered on, the remote control port is open to the oil tank and the hydraulic pump is unloaded to reduce energy consumption (such as the standby state of the die-casting machine).

Safety protection: The valve is closed when the system is working normally. When the load exceeds the specified limit (such as overload of the stamper), the overflow valve opens and overflow to prevent overpressure damage to the system.

Proportional control characteristics (proportional relief valve)

The core control part is a proportional electromagnet that receives the controller's electrical signals (such as 0-800mA or 0-2A), realizing stepless adjustment of pressure and complex control logic (such as pressure changes linearly with time).

Advantages: High adjustment accuracy (Error ≤±1%), fast response speed (millisecond level), suitable for scenarios where dynamic pressure control is required (such as test machine force/pressure control).

Pilot structure (high voltage working condition optimization)

Compared with the direct-acting relief valve, the pilot design controls the opening of the main valve through the pilot valve, which is suitable for high-pressure and large flow conditions (such as the rated pressure can reach 31.5MPa and the flow rate reaches 1000L/min).

Advantages: Stable pressure regulation, smaller leakage, and strong anti-pollution ability (the valve core is sensitive to action and is not easy to block).

3. Application advantages: efficient, reliable, easy to maintain

High efficiency and energy saving

The superimposed design reduces pressure loss (the oil passes through the internal passage of the valve plate) and reduces energy consumption (10%-15% energy savings than traditional systems).

The internal oil drain design simplifies the oil circuit and avoids the use of the installation space by the external oil drain pipe.

High reliability

The core components are precision-processed using alloy steel (such as the tolerance of the valve core and the valve body is controlled at the micron level), and are combined with high-precision grinding technology to ensure long-term stability.

High-quality materials (such as cast iron valve bodies and hard steel valve cores) improve durability and can last tens of thousands of hours.

Easy installation and maintenance

Standard installation sizes and user-friendly design (such as pressure adjustment handles, lock nuts) are convenient for on-site operation, and technicians can quickly complete pressure setting and adjustment.

The modular design allows a single valve to be disassembled and replaced separately when it fails, without affecting the overall oil circuit and reducing maintenance costs.