back-pressure valve

基本解释

The utility model relates to a back-pressure gauge valve which is freeze proof and theft proof.
本实用新型涉及一种防冻、防盗回压表阀。
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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.
回压阀被设计用来顶住来自下面的压力，使流体仍能从上面抽出，如井控时可能需要这种阀。
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.
开发了一种集液控单向阀、溢流阀和自调整背压阀于一体的背压自调整复合阀。