上升与下降电磁阀的控制；

and an increase in decline solenoid valve control;

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防裂阀可防止油管破裂导致工作台失控下降的事故。

Crack resistant valve can prevent the oil pipe rupture resulting in table control falling accident.

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安全阀可以防止因液压系统故障等原因而引起的油缸输出推（拉）力急骤下降，可确保加工安全。

The pressure safety devices can help to retain the draw bar pulling force in the event of a breakdown of the hydraulic system.

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