Do you know how a hydraulic jack works?

What makes you apply a small force to it to raise your car? Yes, it is a jack that can be carried with the car to perform basic mechanical operations. However, in addition to this portable jack, there are various jacks available on the market. Jacks can be classified according to the force generation mechanism. We have mechanical jacks, electric jacks, hydraulic jacks and pneumatic jacks. All these types of jacks can lift heavy objects, but their application fields, lifting capacity and design will be different.


A hydraulic jack is a mechanical device that uses fluid power to operate. With the help of hydraulic jacks, heavy objects can be lifted easily with a small amount of force. Generally, the lifting device uses hydraulic cylinders to apply initial power. Hydraulic jacks have a wide range of applications in railways, defense, construction, aviation, cargo handling equipment, hydroelectric power plants, mining and lifting platforms. The smooth and smooth movement of the variable speed jack under varying or maximum loads makes the hydraulic jack suitable for all of the above applications. Similarly, the use of hydraulic jacks can provide greater lifting capacity over greater distances.

When we look back on history, the patent for the portable hydraulic jack was granted to Richard Dudgeon in 1851. Prior to this, William Joseph Curtis applied for a British patent for hydraulic jacks in 1838.



Oil storage tanks or buffer tanks, hydraulic cylinders, pumps, check valves and release valves are important components of hydraulic jacks, which help lift heavy objects. Like every hydraulic system, the oil storage tank will store the hydraulic oil and deliver the pressurized hydraulic oil to the connected cylinder with the help of the hydraulic pump. A check valve located between the cylinder and the pump will direct the flow. When fluid enters the hydraulic cylinder, the piston extends and pressurizes the second hydraulic cylinder. After finishing the work, the release valve is used to retract the hydraulic piston. The capacity of the reservoir or buffer tank will depend on the hydraulic oil demand for the cylinder to extend and retract. More detailed information on hydraulic jacks is described below.


How does a hydraulic jack work? The working principle of hydraulic jacks is based on the principle of Pascal pressure. That is, the pressure applied to the fluid stored in the container will be equally distributed in all directions. The important components of a hydraulic jack are the hydraulic cylinder, the pumping system and the hydraulic oil (usually oil). Select hydraulic jack fluids by considering certain fluid properties (such as viscosity, thermal stability, filterability, hydrolytic stability, etc.). If you choose a compatible hydraulic oil, it will provide the best performance, self-lubrication and smooth operation. The hydraulic jack design will consist of two cylinders (one small and the other large) connected to each other by pipes. Both hydraulic cylinders are partially filled with hydraulic oil. When a smaller pressure is applied to the smaller cylinder, the pressure will be evenly transferred to the larger cylinder through the incompressible fluid. Now, the larger cylinder will experience the force multiplication effect. The force applied to all points of the two cylinders will be the same. However, the force generated by a larger cylinder will be higher and proportional to the surface area. In addition to the cylinder, the hydraulic jack will also include a pumping system to push fluid into the cylinder through a one-way valve. This valve will restrict the return of hydraulic oil from the hydraulic cylinder.


Bottle jacks and plate jacks are two types of hydraulic jacks. The bearing pad supported by the vertical shaft is responsible for balancing the weight of the lifted object. Jacks are used for the maintenance of car and house foundations, as well as for short vertical lifts. Jacks can provide a wider range of vertical lifting. Therefore, these jacks are commonly used in the mining industry. Unlike the bottle lifter, the horizontal shaft pushes the crank to connect to the lifting pad, and then lifts it vertically.


We can draw conclusions after discussing some troubleshooting techniques for hydraulic jacks. What should I do if the hydraulic jack cannot lift objects? Low oil level may be the cause of this fault. Therefore, first, you need to check the oil level. If you find that the amount of oil in the system is insufficient, please refuel. Leaks or seal failure may be another cause of this situation. If the gasket is damaged, the gasket on the compression cylinder needs to be replaced.

Post time: Sep-30-2021