Working Principle of the Emergency Breakaway Valve for the Loading Arm
The emergency breakaway valve for the loading arm is a safety device, typically installed at the front end of the loading arm. Its main function is to automatically and rapidly disconnect from the tank truck or other connected equipment in case of an emergency, such as when the loading arm experiences unexpected pull or pressure beyond the preset limit. This helps protect the loading arm and related equipment, preventing leakage accidents and ensuring safety during fluid loading and unloading operations.
The breakaway valve (shut-off valve) emergency disconnect system maximizes safety in fluid transportation for both marine and land-based loading arms (land-based fluid loading arms). With a simple and unique design, this system allows the loading arm to safely disconnect automatically without leakage when it exceeds the rated load of the operating system. In the event of a hazard, the emergency breakaway valve (emergency shut-off valve) ensures quick valve closure, minimal leakage, and relatively low pressure loss. The breakaway mechanism ensures that the equipment can automatically and quickly disconnect during an emergency, while also providing a "buffer period" before disconnection to prevent accidental disconnections during regular operations, which could affect normal loading and unloading tasks.
Operating Process Under normal working conditions, after the loading arm is connected to the tank truck, the safety bolt should first be manually removed (the dovetail nut should be unscrewed), and then the valve can be opened to start the loading or unloading operation. After the operation is complete, the safety bolt should be reinstalled, and the loading arm can be separated from the tank truck to reset the arm. In an emergency, if the tank truck moves unexpectedly, the emergency breakaway valve will automatically disconnect, preventing leaks caused by accidental movement of the tank truck during the loading and unloading process.
Safety Performance The loading arm emergency breakaway valve has a very reliable shut-off action, making it ideal for cutting off or regulating and throttling media. It allows the equipment to automatically and quickly disconnect in an emergency, avoiding disconnections during regular operations that could affect the normal loading and unloading process. Additionally, the breakaway mechanism ensures that the equipment can automatically and quickly disconnect during an emergency, while providing a buffer period before disconnection to prevent accidental disconnections during normal operations.
Sealing Performance After disconnection, the end connected to the hose will inevitably fall to the ground and be dragged along with the tank truck. To prevent sparks from strong collisions, the material is usually made of stainless steel (typically 304) or brass. However, the emergency disconnect device for the loading arm is different: neither end will fall to the ground, and carbon steel can be used. Considering rust prevention, all metal components are surface-coated with hard chrome (or chemically nickel-plated). This ensures that after an emergency disconnection, the two separated parts can effectively seal.
Restoration Process After disconnection, the pipeline needs to be drained before restoration. Before restoring the emergency disconnect device, the main and secondary seals should be checked for damage (such as burning). If damaged, the main seal seat should be removed and the main seal replaced; otherwise, only the breakaway bolt needs to be replaced with a new one.
