Actuators are most commonly either electric or pneumatic and can be equipped with a variety of functions and accessories for controlling valve operation.

常见的执行机构是电动执行机构或气动执行机构，而且可以配置各种各样的功能和附件来实现各种阀门操作控制要求。

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On-off valve shall be pneumatic ball valve, and the leakage class is V or VI. All the valve accessories such as limit switches, solenoid valves and filter regulators shall be supplied with the valves.

切断阀采用气动球阀，泄漏等级为V或VI级，限位开关、电磁阀、空气过滤减压阀等应随阀成套供货。

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