Why are engine shut-off (shut-down) valves used?
Diesel engine air-intake shut-off valves are installed to ensure a means of stopping the engine in the event of an uncontrolled over-speed caused by an inhaled combustible gas or fumes from the surrounding atmosphere.
The requirement for air-intake shut-off valves may also be enforced by; government regulations or laws, Oil and Gas company Safety Policies, Oil and Gas service and supply company Safety Policies, Petrochemical Plant Safety policies, Pipeline construction and Operator company Safety Policies, and the bulk fuel and gas transportation industry policies to name a few.
In the event of an inhaled combustible gas induced engine over-speed, shutting off the engine electronics and / or the ignition system will not stop a running diesel engine because it can continue to run and over-speed due to compression ignition of the combustible gas in the engine cylinders.
Without an engine shut-off valve, an uncontrolled engine over-speed can result in a catastrophic engine failure and / or the ignition of the surrounding combustible gas cloud or fumes. Actuating a gate valve type intake shut-off valve, and therefore eliminating the engine air-supply and the inhaled combustible gas or fumes is the best method of stopping such an over-speeding engine.
The installation and use of a gate valve type air-intake shut-off valve is the easiest and most cost-effective way to safeguard against catastrophic engine failure and gas cloud ignition.
