Currently, there is no single national standard that explicitly prescribes specific upper and lower liquid level limits for liquefied petroleum gas (LPG) storage tanks; however, relevant codes do specify requirements regarding the filling coefficient.
Upper Liquid Level Limit
According to the national standard *Code for Design of Oil and Gas Gathering and Transportation* (GB 50350), a filling coefficient of 0.9 is recommended when storing LPG under ambient temperature and pressure. Consequently, to ensure safety, the actual liquid level should generally not exceed 90% of the tank's capacity.
Lower Liquid Level Limit
National standards do not explicitly define a lower liquid level limit; this is typically determined based on specific operational scenarios and equipment requirements. Maintaining a reasonable minimum liquid level is essential to ensure the stable operation of the gas supply system and to prevent pump cavitation (or "dry running").
For final operational parameters, one must strictly adhere to the technical manuals provided by the equipment manufacturer and comply with the regulations of local fire safety and regulatory authorities.
