1. Emergency Cut-Off Valve Product Overview

The Emergency Cut-Off Valve is a safety-critical component designed for installation at the inlet pipeline of submersible pump-type fuel dispensers. Engineered to mitigate fire and contamination hazards, the valve automatically and rapidly isolates the fuel flow in the event of severe emergency situations, such as vehicle collision, dispenser knockdown, or fire exposure.

2. Emergency Cut-Off Valve Technical Specifications & Performance Data

Technical Parameter	Specification / Requirement
Main Part Material	Ductile Cast Iron
Nominal Pressure	0.2 MPa
Inlet & Outlet Connection	NPT 1.5″ Threaded Joint
Flow Rate Range	Up to 120 L/min
Closure Speed (Rate of Valve Closure)	$\le 0.5\text{ s}$
Operating Medium	Gasoline, Diesel, Kerosene (Coal Oil)
Operating Ambient Temperature	-20°C to +55°C

3. Emergency Cut-Off Valve Key Features & Working Principle

Rapid Automatic Containment: Features a high-sensitivity mechanical shear zone and triggering mechanism that shuts off fuel supply within 0.5 seconds during fire or structural impact.
Heavy-Duty Construction: Built from robust ductile cast iron to ensure structural integrity and high chemical resistance against various fuel types.
Broad Media Compatibility: Suitable for conventional fuel handling systems including gasoline, diesel, and kerosene/coal oil.

4. Emergency Cut-Off Valve Rigorous Installation Guidelines

To guarantee proper operation and structural integrity under impact, strict compliance with the following installation procedures is required:

Piping & Sealing:
- Connect fuel pipelines using oil-resistant, non-hardening flexible piping.
- Apply appropriate thread sealant to threaded connections. Avoid excessive tightening to prevent casting strain.
Torque Application:
- Do not apply wrenching torque across the shear slot, as this may twist off or fracture the valve body.
- Secure the hexagonal lug on the valve top using a primary wrench while tightening the pipe joint with a second wrench.
Shear Groove Positioning:
- The shear slot (groove) must be flush with the top of the island/dispenser base, or within ± $\pm 10\text{ mm}$ relative to the base level.
- Critical Caution: If the slot is misaligned outside this ± $\pm 10\text{ mm}$ tolerance, heavy collision forces may rupture the inlet/outlet piping connections instead of shearing cleanly at the intended slot.

5. Emergency Cut-Off Valve Maintenance & Component Replacement Procedures

5.1 Replacement of Top Slot Assembly

If the upper section of the valve requires replacement due to impact activation or inspection findings:

Safety Isolation: Shut off the power supply to the submersible pump and oil drainage systems. Manually close the emergency valve.
Disassembly: Unbolt the top hexagonal screw, pull out the valve top assembly, and remove the internal gasket.
Reassembly: Apply grease/butter evenly onto the gasket, seat the new valve top, and securely tighten the top hexagonal screw.
Quality Standard: Replace any component that displays even slight surface damage or distortion.
Re-commissioning: Reinstall the dispenser fuel delivery lines and perform a leak/pressure test before resuming normal operation.

5.2 Routine Preventive Maintenance

Operational Test: Manually open and close the valve mechanism several times to ensure smooth actuation, then reset it to the normal operating position.
Inspection Frequency: Perform this operational verification and structural visual check at least annually to assess valve condition and evaluate whether maintenance or part replacement is required.

Emergency Cut-Off Valve Factory

Emergency Cut-Off Valve ESV40/ESV40A