Materials & Structure:​ The valve body and shutoff sealing surfaces use corrosion-resistant, wear-resistant alloy with precision-machined and hardened treatment. Seals are high-performance fluoro-carbon rubber (FKM) to ensure shutoff reliability over long service. The unit is configured with a single-speed frameless resolver as the position-feedback element; the driver interface is compatible with the standard LQ25 series.

Working Principle:​ Under normal operation the valve acts as a standard metering valve—the driver adjusts the rotary plate position per the 4–20 mA command to precisely control fuel flow. The internal ΔP regulator maintains a constant differential across the metering port. When a shutoff command is issued or the driver loses power, a spring force or motor brake rapidly returns the plate to the fully-closed position, cutting off fuel.

Installation Requirements:​ Install in the main fuel-supply line with an upstream filter. Orient the valve body to facilitate actuator heat dissipation and maintenance. Ensure the electrical shutoff-command circuit is independent and reliable. Perform a leak-tightness verification test at the fully-closed position.

Usage Precautions:​ Regularly inspect internal sealing performance in the shut-off state; repair immediately if leakage is found. Avoid prolonged operation at partial opening to prevent uneven seat wear. Perform periodic emergency-shutoff tests to validate response time. Manually cycle the valve before initial start-up after long-term storage to confirm no sticking.