back valve

基本解釋

Casing back pressure valve plays a important role in well cementing operation as a casing accessories.
套管回壓閥作為一種簡便的套管附件，在固井施工作業(yè)中起著重要作用。
According to flow in a different, balanced spool valve the pressure can be pre-pressure, can also be a back pressure valve .
根據(jù)流向不同，平衡閥芯所受的壓力可以是閥前壓力，也可以是閥后壓力。
The performance and structure of existing back valve are introduced, and an ultra-low pressure startup back valve, which can be fixed freely in any pipes with any directions, is designed.
對現(xiàn)有止回閥的性能、結(jié)構(gòu)進(jìn)行了分析，設(shè)計了一種可以隨意安裝于各種方向的管道中的超低壓力啟動上回閥。

We've yet to hear back from Valve for clarification.
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