The piston may be connected to the upper end of the connecting rod either directly (trunk piston type), or indirectly (crosshead type).

活塞与连杆上端的连接，既可以是直接连接(筒状活塞式)，也可以是间接连接(十字头式)。

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Upper and lower piston rings are arranged inside a piston gaseous ring groove, and openings on the two-piece piston rings are mutually staggered.

在一个活塞气环槽内设有上下二片活塞环，二片活塞环上的开口相互错开。

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In trunk-piston engines, a horizontal pin within the piston is encircled by the upper end of the connecting rod. This by far the most common construction.

在筒状活塞式的发动机中，活塞与连杆上端通过一个水平销子连接。这是最常见的一种结构。

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The piston then moves back up to sustain the reaction in the upper reactor, and so on.

ECONOMIST: Nuclear power