back-pressure valve

基本解釋

The utility model relates to a back-pressure gauge valve which is freeze proof and theft proof.
本實(shí)用新型涉及一種防凍、防盜回壓表閥。
ip.com
The back-pressure valve is designed to hold pressure from below yet enable fluids to be pumped from above, as may be required for well-control purposes.
回壓閥被設(shè)計(jì)用來頂住來自下面的壓力，使流體仍能從上面抽出，如井控時可能需要這種閥。
www.infopetro.com.cn
An automatic back pressure adjustment complex valve combining hydraulic control check valve, overflow valve and auto-adjusting back pressure valve has been developed.
開發(fā)了一種集液控單向閥、溢流閥和自調(diào)整背壓閥于一體的背壓自調(diào)整復(fù)合閥。