Jacks

A jack is a device for lifting, lowering or moving various items in space. By purpose, jacks are divided into load-lifting and alignment jacks.

The type of jack is selected based on the task. Screw and diamond-shaped jacks are suitable for passenger vehicles. Hydraulic jacks are the most versatile, suitable for most work.

By operating principle, 4 types are distinguished:

• Hydraulic;
• Wedge;
• Rack-and-pinion;
• Operating on compressed air.

Design and operating principle

A screw jack is used for installation work. The main part of the device is a screw, on which a cup is fixed by means of a hinge, driven by a handle. The weight is held at the set height due to the self-locking of the screw.

A wedge jack is used for moving a load or equipment in height, during alignment. It is distinguished by minimal dimensions, which improves ease of use.

A lever-and-rack jack has increased load capacity with a lifting height of up to 35 centimeters. The drive is a lever mechanical one. A rack moves inside the frame. A head is fixed to it at the top, on which the lower element additionally rests.

Hydraulic jacks are the most widespread. Several groups of devices are distinguished:

1. Load (cargo) jacks — used for moving loads when installing or dismantling equipment in various fields of economic activity. They have high lifting force and service life with relatively small size and weight.
2. Universal. They have threads both on the outside of the body and holes in the base; in some models the thread is also applied to the rod.
3. Double-acting hydraulic. Can be used in any position.
4. Self-contained. Have a built-in pump with a handle. In some cases the design is supplemented with a screw to compensate for a small distance between the support mechanism and the load.

Pneumatic jacks are designed for mounting various equipment.

Manufacturing materials

The mechanical and hydraulic elements of a jack must have increased mechanical strength, so they are made of high-strength alloy compositions capable of withstanding loads of several tons.

Elastic models have a shell structure made of reinforced materials. The pressure level of such devices does not exceed 0.8 MPa, which improves safety during operation.

How to choose correctly?

The type of jack is selected based on the task. Screw and diamond-shaped jacks are suitable for passenger vehicles. Hydraulic jacks are the most versatile, suitable for most work.

Next, you need to determine the maximum load that the jack is expected to move.