气动活塞式执行机构可分为单作用和双作用两种。

Pneumatic piston actuators can be divided into single and double acting two.

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智能SIPART PS 2电气定位器用于气动直行程和角行程执行机构“2线制；不带hart；”“双作用；外壳：塑料”。

Intelligent SIPART PS2 electrical locator for pneumatic straight travel and quarter-turn actuators "2 wire system; without HART;" "Double role; shell: plastic".

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