排出管

The actual production needs from oil field,aimed at tractor hoist that need replace pipe string and outside slippery jet pump that isn′t satisfied with discharge fracturing quickly in reality,a new type of jet pump inside sleeve type of jet pump is designed.

针对外滑套式射流泵在油田应用中不能满足压裂后快速排液的现况，研制出了一种新型的内滑套式射流泵，并提出了射流泵、喉嘴距、喉管长度、扩散管角度及长度的计算公式。

Do not gum up the work by telling mother what we are going to do .

别告诉母亲我们要干的事，那会把事情搞糟的。

In recent years, application of the partial prestressed concrete beam s is developed.

近年来，随着部分预应力砼梁应用的推广，发现我国规范所采用的名义拉应力法的计算结果不稳定。