Pump case are welded castings steel and steel plates.

泵壳是由铸钢与钢板焊接而成的。

If the pump is fitted with oil drain port, firstly fill oil in the pump case.

有泄油口的泵，要向泵壳体中灌满油。

The designer may lower the pressure on the packing by placing a throat bushing in the pump case (Figure).

设计者可在泵壳内放置喉道补心以降低在填料上的压力(图)。

Packing or seals are used to prevent the pump leaking around the shaft where it emerges from the pump case.

为防止轴穿出泵壳处轴周围的泄漏，使用填料或密封。

The factors affecting the best phase matching condition and the methods to expand the tunable range of VUV output in the weak pump case are discussed.

特别着重讨论了影响最佳相位匹配的因素和在弱泵浦光条件下增大调谐范围的途径。