Jiangsu Chengsen Jiaze Energy Technology Co., Ltd.

Liquefied natural gas (LNG), abbreviated as “LNG”, is a series of natural gas cryogenic condensation processes that liquefy at ultra-low temperatures (-163 °C) to become liquefied natural gas. The main components are methane (CH4) and ethane (C2H6). It is recognized as the cleanest energy source on earth, colorless, odorless, non-toxic and non-corrosive. Its volume is about 1/625 of the volume of the same amount of gaseous natural gas, and the weight of liquefied natural gas is only about 45% of the same volume of water.
First, LNG natural gas vehicles, natural gas is very low temperature liquid storage temperature is very low, so when using vehicles in winter should pay attention to:
1. After filling is complete, secure the dust cover of the recharging seat and refill seat to protect it. The presence of dust or other debris on the surfaces of the refueling seat and the refueling seat will affect the sealing accuracy with the air gun and the air return gun, resulting in the leakage of the liquefied gas. When filling the gas, it must be ensured that the gas filling port is clean, avoiding water and dirt entering the gas cylinder and blocking the pipeline.
Expand the remaining 81%
3. When icing occurs in pipes or valves, use clean, oil-free warm water or hot nitrogen for thawing. Do not use hammers or other objects to knock.
4. The filter element must be cleaned or replaced in time to avoid over-contamination of the filter element.
5. Before the vehicle stops, it needs to run at idle speed for 3 minutes. After the water temperature is stable, it will stop after power off.
6. When the vehicle is parked overnight, close the pressure booster valve, liquid outlet valve, and vent valve, and start the vehicle until it stops automatically. This will prevent the ice block in the pipeline due to nighttime low temperatures.
7. There should be no ice freezing on the supercharger coil. If there is any ice or dirt, please clean it in time to ensure that the supercharger runs smoothly.
8. When the vehicle starts, idle 3 minutes. When the water temperature reaches 40 degrees, run the vehicle again.
9. Before the vehicle is running, turn on the liquid outlet valve (turn it clockwise and turn it counterclockwise). When it is turned on, please operate it slowly. If the opening speed is too fast, the over-flow valve will automatically close and the gas cylinder will not be able to supply air.
10. Please check the tightness of the cylinder fittings every week, and use hammers or other hard objects to strike the pipes or fittings.
Second, the common gas system fault diagnosis and maintenance

Fault phenomenon	Cause Analysis	Solution
Inflated bottle pressure is too hig	Refueling equipment setting pressure is too high	Apply proper pressure to refueling equipment regulator
Hot bottle filling	Normal phenomenon	Press return pipe to vent
When the gas pressure is too high	Saving valve improper adjustment	Adjust the saving valve to the appropriate pressure
Save valve failure, damage		Repair or replace saving valve
Rising quickly after filling	Overfilling	Fill according to the rated amount
Hot bottle filling	normal phenomenon	Increase gas consumption
Loss of vacuum		Contact the Santa Fe local service station
Bottle pressure is too low	Saving valve improper adjustment	Adjust the saving valve to the appropriate pressure
Gas pipeline and pipe leakage		Repair pipelines and fittings. And leak test again
Liquid temperature is too low or quality problems		Check liquid quality and temperature
Before and after filling, the pressure gauge does not respond	Bad pressure gauge	Replace pressure gauge
Safety valve opens, pressure gauge does not respond	Bad pressure gauge	Replace pressure gauge
Cylinder head frosting	May be using gas	normal phenomenon
	There may be leaking fittings	Check, then follow the operating procedures
Bottle sweat or frost	Low ambient temperature, high air humidity	normal phenomenon
Vacuum failure		Contact the Santa Fe local service station
Safety valve opens	Liquid storage time is too long	Immediately use air or vent
Turbocharged fast		Check cylinders are normal
Safety valve set pressure or fault		Replace safety valve according to operating instructions
Level display zero	The cylinder has run out of liquid	Fill the cylinder with the required amount
Improper setting of converter		Reset the converter capacitor value
Display or converter is damaged	Check each part	Repair or replace
After the liquid in the bottle is used up, the liquid level shows the full position	Improper setting of converter	Reset the converter capacitor value
Display or converter is damaged	Check each part	Repair or replace
Wire breakage or connection isotonic water	Check wire	Dry the water and reset the connection
Supply air temperature is too high or too low	Reasons for hot water supply	Adjustment of hot water supply
Supply pressure is too high or too low	Saving valve, pipeline pressure regulating valve	Check the set pressure is accurate, work is normal
No gas supply	The gas and liquid in the cylinder have been used up	Fill the bottle
Fluid supply valve is not open		Find open valve
Solenoid valve does not open or malfunction		Check the power supply is normal,Solenoid valve is intact

Third, the inspection of the main components of the gas cylinder is as follows:

Maintenance content	Maintenance interval	Maintenance
Gas cylinder and bracket connection nut	Fifteen days	Check and tighten the nut
Each pipe connection site nut	Every time you check out the car	Soap water visual leaks
Vaporizer	Six months	Clean internal scale
All parts of the valve	One year	Soap water detection leak
Safety valve	One year	Technical supervision department annual inspection
Pressure gauge	One year	Technical supervision department annual inspection
Cylinder vacuum	One year	Pressure test
Comprehensive leak detection	Frequently	Airtight test or leak detection

Fourth, gas supply system components
◆ Vent valve ---------- ------ for pressure relief cylinders
◆Outlet valve ------ ----------Control LNG fuel
◆Self-pressure booster --------------Cylinder auto-pressurization under heavy load
◆ Liquid-filled Check Valves ------------- Prevent Liquid Fillback
◆ Saving valve ------------- --- Control the internal pressure of the cylinder
◆Overflow valve ----------------- fuel leakage when pipeline breaks
◆Boost regulator valve------------- cylinder auto-pressurization
◆ Pressure gauge ----- ----------- read the cylinder and engine intake pressure
◆Main safety valve --------- Pressure relief gas cylinder
◆ Deputy safety valve --------- Pressure relief gas cylinder
Fives. Emergency handling
1, emergency personnel dress requirements
Eyes or skin contact with cryogenic liquids can cause cold burns similar to burns. Be careful not to spill or spill them. Protect eyes, skin, and other parts that are prone to contact with cryogenic fluids. Wear protective goggles or face shields; Wear protective gloves and long sleeves that are easy to remove and protect your arms. Wear long pants that cover your shoes to block the spilled cryogenic liquid. The emergency handler’s clothing should be made of cotton, preferably with no pockets or rolled up parts. Do not wear chemical fiber clothing that may cause static electricity.
2, accident or fire situation processing
In the event of an accident or other unexpected situation, it is necessary to promptly close the fuel supply valve of the gas cylinder, ensure air circulation, set up a safe area, evacuate personnel, and maintain a safe distance. If a fire situation occurs, care should be taken to keep the gas cylinder away from the ignition point. Call the police. When the valve cannot be closed or the leak cannot be blocked, the liquid leaking point must not be directly sprayed with water. A dry powder (preferably potassium carbonate) fire extinguisher is recommended.
Warning: You cannot use water to spray LNG liquids. This can cause large amounts of LNG to evaporate and increase the fire.