How to Select a Fluid loading arm

How to choose a more reasonable form of fluid loading and unloading arm (crane tube)? The operating forms of the crane tube (fluid loading and unloading arm) for automobile loading and unloading vehicles can be divided into manual operation and pneumatic transmission. It can also be divided into upper and lower mounting types based on whether the crane tube is connected to the external tank car above or below.
So far, in the use of loading and unloading cranes in our country's tank trucks, liquefied petroleum gas, liquid ammonia, and other media are all bottom mounted, while most other media are top mounted. The upper loading and unloading crane can be divided into open loading and unloading and closed liquid loading and unloading. In principle, it is safer and more environmentally friendly to load flammable and explosive media under closed liquids. Open loading is only suitable for heavy, sticky oil and other media because it is very easy to generate static electricity; Nowadays, our country is paying more and more attention to environmental issues. From the perspective of environmental protection, volatile, toxic, harmful, and pungent odors should be sealed for loading, and China's environmental protection and safety supervision departments also require it.
Regarding whether the loading and unloading arm (crane tube) should be pneumatic or manual: the advantages of pneumatic crane tubes are still very prominent, with automated operation, easier operation, and labor saving. However, due to the high price and high failure rate, maintenance and repair are also more troublesome than manual crane tubes.
In summary, the selection of pneumatic or manual crane tubes should be based on comprehensive considerations of human and economic conditions