How to retract a jack?

1 Answers
Linda
07/30/25 6:43am
The method to retract a jack is: You need to unscrew the hydraulic valve to release the hydraulic pressure before retracting it. Turn the vent valve at the bottom counterclockwise. A loaded jack will descend automatically, while an unloaded one can be retracted by adding some weight on top or pressing down the lifting column. Self-lowering screw jacks have non-self-locking threads and are equipped with a brake. Releasing the brake allows the jack to descend quickly on its own. A jack refers to a compact lifting device that uses a rigid lifting component as the working mechanism to elevate heavy objects within a small stroke via a top saddle or bottom claw. Jacks are primarily used in factories, mines, transportation sectors, and other industries for vehicle repairs, lifting, and support tasks. They feature a lightweight yet sturdy structure, are flexible and reliable, and can be carried and operated by a single person.
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