With the continuous improvement of the country and the people's environmental protection requirements, the country promulgated three standards in 2007, namely: GB20950-2007 "Air Pollution Emission Standard for Oil Storage Depots", GB 208591-2007 "Air Pollution Emission Standard for Gasoline Transportation", GB20592-2007 "Gas Station Air Pollution Emission Standard". The implementation of these three standards has greatly promoted the technical transformation of liquid storage and transportation equipment, especially the environmental protection, safety, and energy saving in the process of liquid receiving and sending have received more attention. As a result, airtight loading and unloading special crane pipes for vapour recovery and closed loading and unloading crane pipes came into being. Airtight loading and unloading truck crane pipes have been used more and more widely in the operation of oil and toxic material loading and unloading trucks, which greatly meets the needs of liquid storage. Environmental protection and safety requirements during transportation.
