How to Use the Three Valves on an LNG Vehicle?
2 Answers
When the buffer tank pressure reaches zero, first open the valve a quarter turn. You will hear a hissing sound of gas escaping. Once the sound stops, fully open the valve and then turn it back one full turn. When the cylinder pressure is below 0.8 MPa, open the valve while simultaneously activating the pressurization valve. Open the pressure relief valve when replacing cylinder components or when the cylinder pressure is too high and needs to be emptied.
I've been driving LNG vehicles for over a decade, and those three valves are actually crucial: The filling valve is for adding fuel - you must first align and securely connect the refueling station's nozzle to it, ensuring an airtight seal without gas leakage. The vent valve is for discharging excess gas - connect it before refueling to direct evaporated gas out and prevent pipeline pressure buildup. The relief valve is for emergency use only - normally untouched, manually operated only when pressure gets too high. Remember to wear gloves during operation as LNG's extremely low temperature can cause frostbite. Tightly close all valves immediately after refueling. Frequently check connections for looseness as leaks can be extremely hazardous. New drivers will master it with practice - safety always comes first.
