The screw jack, also called the mechanical jack, is driven by a manpower through a screw pair, and a screw or nut sleeve is used as a jacking member. The ordinary screw jack 
supports the excess weight by the thread self-locking function, and the framework is simple, but the transmission efficiency is definitely low and the come back stroke is sluggish. The thread of the self-propelled screw jack has no self-locking action and has a brake. When the brake is definitely released, the weight can be quickly lowered alone and the return period can be shortened, but the framework of the jack can be complicated. The screw jack can support heavy objects for a long period, and the utmost lifting capacity has already reached 100 tons, which is trusted. After the horizontal screw is mounted on the low part, the weight can be traversed at a small distance.
Principle useful:
The mechanical jack is one of the types of manual lifting tools. Its compact framework makes reasonable use of the rocking of the rocker to rotate the pinion. It is operated by a set of conical gears to operate a vehicle the screw to rotate and press the lifting sleeve so that the fat rises or decline.
Instructions:
1. Before use, it’s important to check whether the jack is regular, whether the components are flexible, add lubricating oil, and correctly estimate the excess weight of the heavy object. Make use of a jack of appropriate tonnage and avoid overloading.
2. Adjust the method of supporting the teeth on the rocker. Firstly, turn the rocker straight in the clockwise direction by hand to help make the lifting sleeve quickly ascend the top weight.
3. Insert the handle into the rocker hole, move the handle up and down, and the pounds will rise. When the crimson warning line shows up on the lifting sleeve, the handle ought to be stopped instantly. If you want to lower the teeth in the contrary direction, the weight will start to fall.
Precautions:
1. Constantly keep the top of machine clean, verify the internal structure Conveyor Chains frequently, make the pinion in the rocker versatile and reliable, and lift the lifting sleeve openly.
2. The friction surface between the lifting sleeve and the housing must be oiled anytime. Other essential oil filling holes should be lubricated regularly.
3. To be able to consider the basic safety in use, avoid overloading, work with illness, it isn’t appropriate to make use of multiple units in order to avoid danger.
