The screw jack, also known as the mechanical jack, is driven by a manpower through a screw pair, and a screw or nut sleeve can be used as a jacking member. The Conveyor Chains normal screw jack supports the pounds by the thread self-locking function, and the framework is simple, but the transmission efficiency is normally low and the come back stroke is gradual. The thread of the self-propelled screw jack does not have any self-locking action and has a brake. When the brake is normally released, the weight can be quickly lowered by itself and the return period can be shortened, but the structure of the jack is definitely complicated. The screw jack can support heavy items for a long period, and the utmost lifting capacity has already reached 100 tons, which is widely used. After the horizontal screw is usually mounted on the low part, the weight could be traversed at a little distance.
Principle of use:
The mechanical jack is among the types of manual lifting tools. Its compact framework makes reasonable usage of the rocking of the rocker to rotate the pinion. It really is operated by a set of conical gears to operate a vehicle the screw to rotate and drive the lifting sleeve so that the fat rises or decline.
Instructions:
1. Before use, it is necessary to check whether the jack is regular, whether the components are flexible, increase lubricating oil, and correctly estimate the pounds of the heavy object. Make use of a jack of suitable tonnage and steer clear of overloading.
2. Adjust the method of supporting one’s teeth on the rocker. Firstly, turn the rocker straight in the clockwise direction by hand to make the lifting sleeve quickly ascend the top weight.
3. Insert the handle into the rocker hole, move the deal with along, and the weight will rise. When the red warning line appears on the lifting sleeve, the handle ought to be stopped instantly. If you need to lower the teeth in the contrary direction, the fat will start to fall.
Precautions:
1. Constantly keep the surface of the machine clean, verify the internal 
structure frequently, make the pinion in the rocker versatile and dependable, and lift the lifting sleeve openly.
2. The friction surface between your lifting sleeve and the casing must be oiled anytime. Other oil filling holes ought to be lubricated regularly.
3. To be able to consider the safety used, avoid overloading, use illness, it isn’t appropriate to use multiple units in order to avoid danger.