2.1.4 Air pressure vessel
Air pressure vessels should be mounted in convenient positions. Each APV is fitted with a pressure relief valve set at its maximum operating pressure.
A drain valve should be installed at the low point of each APV. The standard APV has a pipe connection on three sides permitting easy drain valve installation. If the APV is mounted with the main connection flange down
本人也是学英语的，只是想找个人翻译下来核对一下。机器的别来糊弄我
