Hydraulic jack is one of the commonly used tools in industrial projects. In order to let customers know more, choose and use a hydraulic jack. TorcStark will introduce its classification, use, working principle, and precautions for use in detail.

Classification and use of hydraulic jacks

It has been two or three hundred years since the emergence of hydraulic transmission technology in the world, and it has only been widely used in cranes and construction machinery in the last century.

Later, due to World War II’s outbreak, many military weapons were also equipped with hydraulic control mechanisms. It was not until the war’s end that this hydraulic technology began to spread to the civilian industry.

But when it comes to the actual rise of hydraulic technology, it’s only a matter of the last few decades. The reason why hydraulic technology is so popular is that the hydraulic transmission device is very light, has low inertia, high power, high efficiency, low noise, and is very durable.

So this hydraulic technology is used in a lot of equipment, one of which is the jack.

The jack is originally a very simple lifting equipment, which is generally used in factories and mines.

Perhaps the most common one is when the vehicle is repaired, it is used to prop up the vehicle for easy maintenance, and that is the credit of the jack.

The use of hydraulic jacks is relatively extensive, because it is very stable in work, compact in structure, and has a self-locking effect, so it is more popular.

The only disadvantage is that the lifting speed is relatively slow, and the lifting height is limited.

Now the hydraulic jacks on the market are also divided into two types: professional hydraulic jacks and general hydraulic jacks.

Generally, special hydraulic jacks are used for special equipment, and special hydraulic jacks are double-acting.

With the progress of the times, the development of various technologies, and the technology of various equipment are also changing, I believe this hydraulic technology is gradually becoming more perfect, and the shortcomings of hydraulic jacks are believed to be improved.

The working principle of hydraulic jack

Jacks are divided into mechanical jacks and hydraulic jacks, and the principles are different.

In principle, the principle on which hydraulic jacks are based is Pascal’s principle.

That is, the pressure of the liquid is the same everywhere. In a balanced system, the pressure exerted on the smaller piston is relatively small, and the pressure exerted on the large piston is relatively large, which can keep the liquid stationery.

Therefore, through the transmission of the liquid, different pressures on different ends can be obtained, so that a transformation purpose can be achieved.

The hydraulic jacks we see commonly use this principle to achieve force transmission.

The mechanical jack adopts the mechanical principle, the handle is pulled back and forth, and the claw is pulled out to push the ratchet gap to rotate. The small bevel gear drives the big bevel gear and rotates the lifting screw so that the lifting sleeve can be lifted or lowered to achieve the function of lifting and pulling force. But not as simple as a hydraulic jack.

Preparations before using the hydraulic jack

Before using the hydraulic jack, you need to do some preparatory work, otherwise, the hydraulic jack will not be used correctly, resulting in low work efficiency and other problems.

So what are the preparations for hydraulic jacks before use? The following are four points of preparation for hydraulic jacks summarized by TorcStark.

When the hydraulic jack is lifting, it is necessary to choose a hydraulic jack with suitable tonnage. The bearing capacity should not be overloaded, and the bearing capacity of the hydraulic jack should be greater than 1.2 times the gravity of the heavy object. The minimum height of the hydraulic jack is appropriate. In order to facilitate removal, the minimum height of the hydraulic jack should be adapted to the clearance at the bottom of the heavy object. When the sleepers are used to support heavy objects during the lifting and landing process, the lifting height of the hydraulic jack should be greater than the sum of the thickness of the sleepers and the deformation of the sleepers.

If multiple hydraulic jacks are used to lift the same equipment, the same type of hydraulic jacks should be selected, and the sum of the rated lifting weights of each hydraulic jack should not be less than 1.5 times the gravity of the equipment it undertakes.

Hydraulic jacks should be wiped clean before use, and each part should be checked for flexibility and damage. Do not remove the quick connector when loaded to avoid accidents and damage to parts. This hydraulic puller should also be highly valued before use.

The hydraulic jack should be placed flat before use, not inclined, and the bottom should be flat. Strictly prevent the hydraulic jack from tilting or overturning due to the subsidence of the foundation or the offset of the load, and a tough pillow or steel plate can be placed at the bottom of the hydraulic jack to expand the pressure-bearing area to avoid accidents from falling or sliding. Do not use oily boards or steel plates as pads to prevent slippage and safety accidents when under force. The position where the heavy object is lifted must be a safe and solid place to prevent damage to the equipment.

Precautions for the use of hydraulic jacks

When using the hydraulic jack, it is not allowed to be eccentric or overloaded, so as to prevent the jack from being damaged and causing an accident. When there is a load, do not remove the quick connector to avoid accidents.

Hydraulic jacks use oil as the medium, and maintenance of oil and hydraulic jacks must be done well to avoid blockage or oil leakage, which will affect the use results.

For new or long-standing hydraulic jacks, because there is a lot of air in the oil cylinder when starting to use, the piston rod may show a small sudden jump. The hydraulic jack can be reciprocated 2-3 times with no load to remove the air in the cavity.

Maintenance of hydraulic jacks:

How to refuel or change hydraulic oil?

Put the jack in a vertical position, and the pump core and the piston are lowered to the lowest point.

Remove the rubber oil plug on the jacket and inject the cleaned hydraulic oil up to the piston port.

Regularly check and lubricate the transmission connecting rod. If it is not in use, the piston rod adjusting screw and pump core should be removed to ensure that the connecting rod is clean and rust-proof.


The above is an introduction to the classification, use, working principle, and precautions of hydraulic jacks. If you have any other questions or need to buy hydraulic jacks, please contact us.