Tank Truck Components Manufacturing

The valve features a 3/2-way configuration with manual push actuation and automatic spring return. It forms a pneumatic interlock system with the emergency shutoff valve at the bottom of the tank and the vapor recovery coupling.

The bottom unloading valve can only be opened after the tank truck is properly connected to the oil depot's vapor recovery line and the required air supply pressure is available. This design provides a safety interlock between vapor recovery and fuel unloading operations, preventing direct unloading without vapor recovery and fuel leakage caused by accidental opening of the bottom valve.

• Oil- and Corrosion- Resistant Materials
  The valve body is available in high-strength engineering plastic (in black) or die-cast zinc alloy. The valve stem is made of brass, and all connection ports are made of nickel-plated brass. These materials provide good oil and corrosion resistance, making the valve suitable for demanding fuel transportation conditions. The one-piece die-cast valve body provides good airtightness and vibration resistance, helping reduce the risk of air leakage.
• Installation and Independent Compartment Control
  The valve is installed near the manhole compartment and vapor recovery coupling on the side of the tank and is connected in series with the vehicle's main pneumatic control circuit. One valve controls the interlock function of a single compartment, while multiple valves can be combined on multi-compartment tank trucks to provide independent interlock control for each compartment.
• Low-Pressure Self-Locking Protection
  The valve is equipped with low-pressure self-locking protection. When the air supply pressure drops below 0.2 MPa, the valve remains locked and cannot be released. If leakage occurs in the pneumatic circuit, the valve automatically shuts off the air supply and resets, returning the bottom valve to the locked position. This design complies with relevant safety regulatory requirements for hazardous-goods transportation.