The parallel seat gate assembly consists of two interchangeable spring loaded discs, a fully guided disc carrier, and retaining pins.
平行阀座闸阀由两个可互换弹簧负载阀瓣，一个全导向阀瓣托架和扣环销钉构成。
2
Note: the first and second check assemblies are not interchangeable and the first check assembly must be removed prior to removing the second check assembly.
注意：第一和第二止回阀总成不能互换，第一止回阀总成必须先拆卸，然后再拆卸第二止回阀总成。
3
An interchangeable method of outer ring assembly of needle roller bearings with or without inner rings is introduced in this paper.