Extending Clutch Brake Service Life for the Most Demanding Applications
Posidyne Clutch Brakes Have 5 Cooling Options for Extreme Conditions
Clutch brakes and brakes can end up in extreme application environments. Dirty, dusty, wet, hot, cold, high inertia loads, high cycle rates, or all at the same application location. How can you ever get a clutch brake or brake to provide decent service? For this discussion let’s just concentrate on 3 issues—high cycle rates, high inertia loads, hot temperatures. The common denominator for all three when relating to clutch or brake solutions is heat.
First it is important to understand that a clutch or brake converts rotating energy to heat. Therefor anytime the clutch or brake is engaged heat is created and must be removed from the friction surfaces. When engaging a clutch approximately 1/3 of the energy coming to the clutch is converted to rotating energy on the output, the balance is converted to heat. When braking 100% of the rotating energy coming into the brake is converted to heat. So, the more energy coming into the friction surfaces the more heat. Note that the Positorq products typically are partially engaged for long periods of time and generate high heat levels continuously.
Heat is one of the biggest enemy’s of clutches and brakes causing friction disc wear, degradation, glazing, loss of torque, hanging or binding, and early failure. Dry friction clutches and brakes have difficulty removing heat from the friction surface causing the challenge of creating higher heat resistant materials, and minimal success by adding fan or water cooling.
Force Control Posidyne clutch brakes, Posistop brakes, MagnaShear brakes, and Positorq continuous slip brakes all feature Oil Shear Technology. Oil Shear Technology is a system of continuously circulating transmission fluid through the friction stack. A thin film of fluid between the friction disc and drive plate separates the parts reducing direct mechanical contact, while the transmission fluid squeezed between them transmits torque through a process known as oil shear technology or hydroviscous. Now we have most of the generated heat created within the fluid which can be cooled in several ways.
Force Control Industries has developed several ways to assure a continuous fluid film of cooled fluid in all of their clutch and brake products. They include;