Before driving an LNG truck on the road, meticulous preparatory work is indispensable. The operation steps surrounding valves and engines may seem ordinary, but they are directly related to the performance of the vehicle, the lifespan of components, and most importantly, driving safety. Jiefang Truck has sorted out key processes. Have you done these operations correctly?
Valve opening operation
Operating method of the liquid outlet stop valve: Turn it to the left to open to the maximum, then turn it back to the right by 1/4 turn
Operation method of the booster valve: Open it to the left to the maximum, and then return it to the right by half a turn
The operation method of the vent valve: Open it to the left to the maximum, and then return it to the right by half a turn
Two major points to note
First of all, be sure to wear gloves when operating the gas cylinder valve. Due to the extremely low temperature of liquid natural gas, direct skin contact can cause serious frostbite accidents.
Secondly, some models of vehicles are equipped with intelligent pressurization systems for their gas cylinders. On the right side of the control box, there is an emergency use button, which can only be operated by professional maintenance personnel or under their direct guidance. During daily use, inspection or parking, drivers are strictly prohibited from touching or operating this emergency button without authorization to prevent system malfunctions, failures or even safety accidents.
When a vehicle is parked for a long time
If the parking time does not exceed two days, the valve usually does not require special operation and can be kept in its original state. However, when the parking time exceeds two days or it is in a cold season, the following strict steps must be followed: First, stop the vehicle steadily and keep the engine running. Then, rotate the liquid outlet stop valve to the right and tighten it until it can no longer be turned. After closing the liquid outlet cut-off valve, you need to wait patiently and let the engine keep running until it completely exhautes the remaining gas in the gas supply pipeline and shuts down by itself. After the engine has completely turned off, tighten the boost valve and the vent valve to the right until they cannot be turned.
If it is a cold season, the warm air system in the driver's cabin should be turned off in advance before the engine shuts down naturally. And after the engine is completely turned off, two no-load start-up operations need to be performed. During the process of closing all valves, special attention should be paid to the following: Just rotate the valve clockwise until you feel a distinct obstruction, which indicates that the closing requirement has been met. Do not forcibly continue to tighten the valve, otherwise it is very likely to cause deformation of the valve core, failure of the seal or damage to the valve structure, thereby posing a significant risk of gas leakage.
Standardized operation of gas cylinder valves is the foundation for ensuring the safe, efficient and stable operation of Jiefang NG models. All truck drivers must strictly follow the above procedures, operate in a standardized manner to protect your vehicles, and Jiefang will accompany you on a smooth journey of thousands of miles.
