Duff-Norton Air Jacks

Hydraulic Jacks 101: A Guide to Their Function and Uses

Hydraulic jacks are essential for lifting heavy loads, making them indispensable for various industries such as automotive, construction, and manufacturing. They use the power of hydraulics to produce a large amount of force to lift, lower, or move large and heavy objects. In this article, we will delve into the inner workings of hydraulic jacks to understand the principles behind their functioning and explore some of their common uses.

The Principle of Hydraulics

Hydraulic systems operate based on Pascal’s Law, which states that when pressure is applied to a confined fluid, the pressure change occurs equally throughout the fluid. This principle is crucial to the operation of hydraulic jacks as it allows them to generate a significant amount of force without requiring a large input force.

The Components of a Hydraulic Jack

A typical hydraulic jack consists of the following components:

  1. Cylinder

The cylinder is the main body of the jack, housing the hydraulic fluid and providing a space for the piston to move up and down.

  1. Piston

The piston is a movable component that slides within the cylinder, creating a pressure difference in the hydraulic fluid as it moves.

  1. Pump

The pump transfers the hydraulic fluid from the reservoir to the cylinder, creating pressure and causing the piston to move.

  1. Reservoir

The reservoir is a container holding the hydraulic fluid when not in use.

  1. Valves

Valves are used to control the flow of hydraulic fluid between the reservoir, pump, and cylinder.

How a Hydraulic Jack Works

The operation of a hydraulic jack involves the following steps:

  1. When the pump handle is pushed down, the pump plunger moves into the pump cylinder, forcing hydraulic fluid through a one-way valve into the main cylinder.
  2. As the fluid is forced into the main cylinder, it creates pressure in the confined space, pushing the piston upwards.
  3. The upward movement of the piston causes the load-bearing surface of the jack to rise, lifting the load.
  4. When the pump handle is released, the one-way valve closes, preventing the hydraulic fluid from flowing back into the pump cylinder.
  5. To lower the load, a release valve is opened, allowing the hydraulic fluid to flow back into the reservoir, reducing the pressure in the main cylinder and causing the piston to descend.

Uses of Hydraulic Jacks

Hydraulic jacks are used in various applications due to their versatility and ability to generate a large amount of force. Some of the common uses include:

  1. Vehicle Repair and Maintenance

Hydraulic jacks are widely used in automotive repair shops to lift vehicles, allowing mechanics to access and work on the undercarriage.

  1. Construction and Infrastructure

Hydraulic jacks are used in construction projects to lift and position heavy equipment, materials, and structures. They are also used for bridge maintenance, structural repairs, and foundation leveling.

  1. Manufacturing and Industrial

In manufacturing plants and industrial settings, hydraulic jacks are used for lifting and moving heavy machinery and equipment during installation, maintenance, and repairs.

  1. Mining and Excavation

Hydraulic jacks are used in mining operations to lift and move heavy equipment and in tunneling projects to support tunnel walls and ceilings.


Understanding the mechanism behind hydraulic jacks allows us to appreciate the power and versatility of these indispensable tools. By harnessing the principles of hydraulics, they offer an efficient and reliable solution for lifting and moving heavy loads across various industries. Whether it’s a car needing repair, a construction project, or a mining operation, hydraulic jacks play a crucial role in making our work more manageable and efficient.

If you are looking for a 100-ton hydraulic jack, look no further than Duff-Norton Air Motor Jacks. Our product line includes heavy-duty lifting devices with capacities up to 150 tons, designed for use in a variety of industries, including railroad, mining, construction, and shipbuilding. Get in touch with us today!

Hydraulic Jacks

Why Hydraulic Jacks Are the Go-To Choice for Heavy Lifting

Heavy lifting can be daunting, especially when dealing with loads that weigh several tons. Hydraulic jacks have been the go-to choice for heavy lifting for decades. These tools use fluid pressure to lift heavy objects, making them ideal for a wide range of applications. This blog will explore why hydraulic jacks are the go-to choice for heavy lifting.

History of Hydraulic Jacks

Hydraulic jacks have been around for over a century. The first hydraulic jack was patented by Richard Dudgeon in 1851. However, it wasn’t until the early 20th century that hydraulic jacks became widely used. The development of high-pressure hydraulic systems enabled hydraulic jacks to lift heavier loads more easily.

How Hydraulic Jacks Work 

Hydraulic jacks work on the principle of Pascal’s law, which states that pressure applied to a confined fluid is transmitted equally in all directions. The jack consists of a cylinder and a piston. The cylinder is filled with hydraulic fluid, and the piston is inserted into the cylinder.

When force is applied to the piston, it compresses the hydraulic fluid, which in turn generates pressure. This pressure is transmitted to the other end of the cylinder, where it lifts the load.

Advantages of Hydraulic Jacks

Hydraulic jacks have several advantages over other types of jacks. Firstly, they can lift heavier loads than mechanical jacks. This is because hydraulic jacks use fluid pressure, which can generate much greater force than a mechanical lever.

Secondly, hydraulic jacks are easier to operate than mechanical jacks. They require less effort to lift heavy loads, making them ideal for people who may not have the strength to operate a mechanical jack.

Finally, hydraulic jacks are more precise than mechanical jacks. The fluid pressure can be controlled more precisely than the force generated by a mechanical lever.

Applications of Hydraulic Jacks

Hydraulic jacks have a wide range of applications. They are commonly used in the automotive industry to lift cars and trucks for repairs. They are also used in construction to lift heavy loads, such as steel beams and concrete slabs.

Hydraulic jacks are also used in the shipping industry to lift and move cargo containers. They are even used in the entertainment industry to lift heavy equipment, such as speakers and lighting rigs.

Types of Hydraulic Jacks

There are several types of hydraulic jacks, each designed for a specific application. The most common type is the bottle jack, which is shaped like a bottle designed to lift heavy loads vertically. 

Another common type is the floor jack, which is used to lift cars and trucks. A third type is a hydraulic cylinder, which is used to lift and move heavy loads horizontally.

Maintenance of Hydraulic Jacks

Proper maintenance is essential to ensure that hydraulic jacks continue to operate safely and efficiently. The hydraulic fluid should be checked regularly and topped up as necessary. The cylinder and piston should be inspected for wear and damage, and replaced if necessary. The jack should also be kept clean and free of debris.

Key Takeaways

Hydraulic jacks are the go-to choice for heavy lifting for several reasons. They can lift heavier loads than mechanical jacks, are easier to operate, and are more precise. They have many applications, from automotive repairs to construction to entertainment. 

Proper maintenance is essential to ensure that hydraulic jacks operate safely and efficiently. With their long history of success, hydraulic jacks will likely remain the go-to choice for heavy lifting for many years.

If you need hydraulic jack parts, look no further than Duff-Norton Air Motor Jacks. Our high-quality parts are designed to keep your hydraulic jacks operating safely and efficiently. Contact us today to learn more about our extensive selection of hydraulic jack parts and how they can benefit your business.