The rings have joints (they are split) so that they can be expanded and slipped over the piston head and into the recessed grooves cut in the piston.

活塞环有接口（也就是有一缝隙），这样可以使端部扩张并滑入活塞上的凹槽中。

youdao

The rings have joints (they are split) so that they can be expanded and slipped over the piston head and into the recessed grooves cut in the piston.

活塞环有接口（也就是有一缝隙），这样可以使端部扩张并滑入活塞上的凹槽中。

youdao