Centrifugal Clutch For Military & Defense

Centrifugal Clutch For Military Defense

A centrifugal clutch is a mechanical device used to transmit torque between the driving equipment (e.g., a motor, engine, or another prime mover) and the driven rotary equipment. It is often employed in applications requiring a “soft start” with no load engagement as it engages only when the input speed reaches above a set value and disengages when the input speed falls below the value. This design makes it suitable for use in a wide range of industrial applications, including in the military and defense industry.

Why Are Centrifugal Clutches Ideal for Military and Defense Applications?

Centrifugal clutches consist of a housing, a hub (for placement of the driving shaft), flyweights, and springs (to keep the flyweights retracted against the shaft). During operations, an increase in input speed results in a proportional increase in centrifugal force. At low speeds, the centrifugal force does not overcome the spring pressure that holds the flyweights against the shaft, preventing the clutch from engaging with the driven equipment. At high speeds, the centrifugal overcomes the spring pressure, allowing the weights to deploy and the clutch to engage. These qualities result in smooth and shock-free acceleration, which is ideal for military and defense applications.

Two main advantages of using centrifugal clutches in military and defense equipment are:

  • Lower risk of engine stalling and damage. Both heavy loads and sudden startups can cause damage to engines and motors. As centrifugal clutches allow for progressive load engagement, they prevent damage during acceleration, ensuring equipment remains stable and reliable throughout its service life.
  • Smaller maintenance requirements. Centrifugal clutches designed and constructed with quality in mind are less likely to break or experience premature wear, reducing the amount of time and money required for maintenance and repair operations.

Military and Defense Applications of Centrifugal Clutches

Centrifugal Clutch for Military Defense
Centrifugal clutches are employed to connect the driving and driven shafts of a wide range of rotary equipment. In the military and defense industry, some of the systems in which centrifugal clutches are commonly found include:

  • Cooling towers (i.e., chillers)
  • Shipboard helicopter elevators
  • Ventilation systems

Case Study: Clutches for a Military Chiller

At BLM Automatic Clutch, we offer high-quality centrifugal clutches suitable for use in a wide range of industries. Below we highlight one example of how we’ve served the military and defense industry.
The United States military formed a contract with an engineering firm to manufacture a 6-inch, F60H clutch for use in a 21 horsepower, 3600 RPM/1500 Idle chiller. In turn, the company partnered with us for the production stage as we demonstrated our ability to accommodate maximum drive capability in a limited workspace.

Our team was responsible for all of the manufacturing work, including material sourcing and precision manufacturing. By employing state-of-the-art CNC lathes, milling machinery, and finishing equipment, we shaped gray iron into the required profile with a ± 0.003 inch tolerance throughout. Afterward, the unit was assembled and subjected to a parkerizing phosphate plating process for corrosion and wear resistance that left the part with a black finish. We produced and shipped 800 units within a six month period.

BLM Centrifugal Clutch Solutions for the Military and Defense Industry

BLM is a recognized leader in the manufacture of centrifugal clutches for demanding applications. All of our products are fully inspected to ensure they meet some of the most rigorous customer specifications and highest industry standards. For this reason, we are often called on by the Navy and Army to manufacture clutch components for special projects.

For more information about the above case study or our general centrifugal clutch solutions and how they benefit the military and defense industry, see the table below or contact us today.

Highlights of this Custom Clutch Machining Project

Project Scope

Worked with an engineering firm contracted by the US military. The BLM clutch was sourced by the firm as the best solution for their design. The belt style used was a timing pulley used for a space limitation with a maximum drive capability.

Product Application

Chiller 21 HP/3600 RPM/1500 IDLE

Product Description

6″ Clutch F60H

Clutch Fabrication Capabilities Applied/Processes


  • Material Sourcing
  • CNC Turning
  • CNC Milling


  • Assembly Plating


Modification of appropriate drawing from portfolio of 4000+ drawings to military specs

Equipment Used to Manufacture Part

CNC Lathes, CNC Mills, Various Machine Shop Equipment

Equipment Used to Manufacture Part

CNC Lathes, CNC Mills, Various Machine Shop Equipment

Tightest Tolerances

± 0.003″

Material Used

Gray Iron

Material Finish

Parkerizing Plating
Color: Black

In process testing/inspection performed

Dimensional Inspection


800 Units

Delivery/Turnaround Time

6 Months

Delivery Location


Product Name

Centrifugal Clutch