The labor-saving wrench can also be called a labor-saving wrench torque multiplier. It is a device that can increase the torque for the operator. Since the output power does not exceed the input power, the output revolution number is lower than the input revolution number. (Torque * speed = power) The labor-saving wrenches of various brands on the market generally achieve torque multiplication through planetary gears, generally with a magnification of 5 to 125 times, and the maximum output torque can reach about 50,000 Nm.

Types of labor-saving wrenches

As a mechanical device used to increase torque output, labor-saving wrenches are widely used in operations that require high torque, such as industrial manufacturing, automobile repair, and construction. According to the design and working principle, there are mainly the following types of labor-saving wrenches:

1. Hydraulic labor-saving wrenches

Hydraulic labor-saving wrenches are also called hydraulic torque wrenches. It amplifies torque through a hydraulic system, using the principles of hydraulic pumps and hydraulic cylinders to convert input hydraulic pressure into output mechanical torque. Hydraulic torque multipliers are usually used in situations where very high torque is required, such as maintenance and repair of large machinery and equipment.

2. Pneumatic labor-saving wrenches

Pneumatic labor-saving wrenches are also called pneumatic torque wrenches. It amplifies torque through compressed air. This type of labor-saving wrench uses air pressure to drive the internal mechanical mechanism to produce greater torque at the output end. Pneumatic labor-saving wrenches are usually used in light and medium-duty industrial applications, especially those that require portability and easy operation.

3. Electric labor-saving wrenches

Electric labor-saving wrenches are also called electric torque wrenches. It relies on an electric motor to increase the torque output. The motor drives the internal gear system to produce greater torque at the output end. Electric labor-saving wrenches are often used in industrial applications that require precise control and continuous high torque output.

4. Manual labor-saving wrenches

Manual labor-saving wrenches usually refer to torque multipliers. It uses the principle of leverage and gear transmission to increase torque. This type of labor-saving wrench is usually operated manually, and by rotating the handle or other input device, a greater torque is produced at the output end. Manual labor-saving wrenches are suitable for use in environments where there is a lack of electricity or compressed air and are easy to carry.

Uses of labor-saving wrenches

Labor-saving wrenches are used to amplify the operator’s torque so that they can tighten or loosen bolts and nuts, especially in applications that require higher torque. This tool can find applications in multiple industries:

1. Automotive repair and manufacturing: In automotive manufacturing and repair, automotive labor-saving wrenches are used to tighten engine components, suspension systems, tire replacement, and other components. For example, when replacing tires on trucks, buses, and private cars, labor-saving tire wrenches are needed to remove and tighten the high-torque bolts that fix the wheel hub.

2. Heavy machinery maintenance: Maintenance and repair of excavators, loaders, and large wind turbines require labor-saving wrenches to ensure the safe tightening of bolts.

3. Energy industry: In wind turbines, oil drilling platforms, nuclear power plants, wind turbines, and hydroelectric power plants, the fasteners of the equipment may require high-torque output tools to ensure safety and performance.

4. Transportation: Labor-saving wrenches are also necessary in the maintenance and manufacturing of railway vehicles, ships, and aircraft.

5. Construction and Infrastructure: High-strength bolts used in the construction of high-rise buildings, bridges, and tunnels require a force-saving wrench to tighten to ensure the stability of the structure.

6. Industrial Equipment Manufacturing: Large industrial equipment, such as compressors, generators, and industrial machines, may require high torque for fasteners to tighten.

7. Automobile Assembly Line: In automobile assembly lines, high-torque bolts used to tighten engines, gearboxes, and other heavy-loaded components require a force-saving wrench.

8. Military and Aerospace: During the assembly of aerospace equipment, such as aircraft and satellites, and military equipment. High-precision fastening applications also require the use of a force-saving wrench.


The labor-saving wrench is one of the most important bolt removal and tightening tools in life and industrial production. The use of the labor-saving wrench improves the work efficiency of workers and ensures safety. TorcStark develops and manufactures various types of labor-saving wrenches. If you are interested in labor-saving wrenches, please feel free to contact us.