The impellers are kept in their proper relationship to each other by spur gear.液轮之间借助于正齿轮保持彼此正常的关系.Mainly by the impellers, pump body and pump cover composition.主要由叶轮 、 泵体和泵盖组成.Welding is one of the important technologie...
Millstones had been cut and laboriously sledged down the rough mountainsides.石磨被琢好,然后费力用雪橇运下那崎岖不平的山坡.The children sledged all day by the lake.孩子们整天在湖面上滑雪橇.The Antarctic expedition sledged along the coastline.这只南极探险队乘雪橇沿着...