Hawei SEH2-3/30F-P-G24-KAL direct acting three-way proportional valve

Hawei SEH2-3/30F-P-G24-KAL direct acting three-way proportional valve

HAWE SEH2-3/30F-P-G24-CAL is a high-performance, high-precision direct acting three-way proportional pressure control valve. It is mainly used in hydraulic systems to achieve stepless, continuous, and proportional electronic control regulation of system pressure.

The following is a detailed introduction to the valve, covering model analysis, working principle, characteristics, typical applications, and precautions:

1. Model Analysis (SEH2-3/30F-P-G24-CAL)

• SEH2-3: The basic model of the Hawei SEH series proportional pressure valve, usually representing a direct acting, three-way structure.

• 30: nominal diameter, referring to the NG6 interface (according to Hawley standards, 30 usually corresponds to NG6, which is the size of the valve body interface). This is the key parameter for selection, which determines the applicable range of flow.

• F: Indicate the specific configuration form of the valve core and valve body.

• P: This valve is used as a pressure control valve. This is its core functional identifier.

• G24: The operating voltage is 24V DC. This is the control voltage for the proportional electromagnet.

• KAL: This valve integrates an analog input control module (usually a 0-10V or 0-20mA signal) and a built-in displacement sensor/closed-loop control electronic amplifier. This is the key to its high-precision control:

• K: Usually refers to an integrated electronic amplifier.

• AL: Usually refers to closed-loop control of valve core position with analog input and inductive displacement sensor, which achieves more accurate and faster pressure regulation, and has good compensation ability for load changes and temperature drift.

2. Working principle

• Direct acting: The movement of the valve core is directly driven by a proportional electromagnet, without the need for pilot control oil. The structure is relatively simple and the response is fast.

• Three way structure: It has three main oil ports: P (pressure oil port), A (working oil port), and T (return tank oil port).

• Proportional control: The integrated electronic amplifier receives analog signals (such as 0-10V) from an external controller (such as PLC). The magnitude of this signal linearly determines the thrust of the proportional electromagnet.

• Pressure regulation: The electromagnetic thrust acts on the valve core, balancing with the spring force at the other end of the valve core and the pressure at output port A (feedback through internal channels). By changing the input signal, the pressure at output port A (i.e. system pressure) can be continuously and proportionally adjusted.

• Closed loop feedback: The built-in displacement sensor monitors the actual position of the valve core in real time and feeds back the signal to the integrated amplifier. The amplifier compares the set signal with the actual position signal, and if there is a deviation, immediately adjusts the current output to the electromagnet to accurately control the position of the valve core, ensuring that the output pressure is highly consistent with the set value.

• 

3. Main features and advantages

• High precision and repeatability: Thanks to the built-in displacement sensor and closed-loop control, the pressure control is very precise and has good repeatability.

• Quick response: The direct acting design avoids the delay of the pilot stage and has excellent dynamic response performance.

• Good hysteresis and linearity: Electronic closed-loop compensation significantly improves the static performance of the valve.

• Strong anti-interference ability: relatively insensitive to oil pollution, high working stability.

• Integrated design: Integrating proportional electromagnets, valve cores and bodies, sensors, and amplifiers into one ("All in One"), saving installation space, simplifying wiring, and improving reliability.

• Stepless adjustment: It can achieve continuous setting of any pressure within its pressure regulation range (specific range needs to be checked in the sample, for example, it may be 5-300 bar).

• Multiple input signals to choose from: Although this is KAL (analog), Hawley typically offers multiple electronic module options.

4. Typical application areas

This valve is suitable for applications that require remote, continuous, and precise control of hydraulic system pressure, such as:

• Pressure testing machine: realizes precise programming and segmented control of testing pressure.

• Injection molding machine: control holding pressure, etc.

• Press (stamping, extrusion): Control the pressure curve of the forming process.

• Machine tool clamping device: realizes adjustable clamping force for different workpieces.

• Material processing equipment.

• Aerospace test bench.

Hawei SEH2-3/30F-P-G24-KAL direct acting three-way proportional valve