Mechanical Power Transmission Newsletter Signup
Get the Engineering360
Stay up to date on:
Systems that use belts and chain drives, gears and gear drives, couplings, clutches and brakes, and other components.

Slipping clutch

Product Announcement from Orttech, Inc.

Ortlinghaus multi-plate slipping clutches (torque limiting devices) are permanently engaged by means of spring pressure. They are factory set to transmit a predetermined level of torque. If this amount of torque is exceeded, as in the case of an overload, the friction clutches are designed to slip for a limited period of time.

These torque-limiting devices can thus be used to safeguard all types of torque transmitting shafts in machines and equipment from overloading and destruction. They are able to smooth out high torque peaks at start-ups and during operation. This is done when the clutch plates start slipping past each other, for a short period of time, when the desired maximum torque is reached. The torque at which a clutch starts to slip can be varied, within limits, by varying the spring pressure.

In this way these friction clutches safeguard gear wheels, shafts and other drive elements from damage and thus guarantee operational reliability for an extended period of time. This reliability helps prevent the need for repairs.

It must be noted that when the friction clutch is slipping, frictional heat is produced and released within the set of plates and that the permissible amount of heat is limited. This thermal loading must be kept within the required limit with the aid of a slip-monitoring device, which would switch off the drive. This is necessary with fast running drives where the critical amount of heat is reached very rapidly when slipping commences.

The principle of a spring-loaded set of plates is the same with all sizes and models of slipping clutches. However, variations are possible in the following areas:

  • The friction combination selected can be steel/organic lining for dry-running, and steel/sintered lining for both dry-running and for wet-running, e.g., in enclosed gearboxes.


  • Friction clutches are available with torques from 6 lb.ft. to 66,300 lb.ft. (9 Nm to 90,000 Nm). The torque at which a clutch starts to slip can be selected or set on each clutch within the range from maximum torque down to 60% of the maximum torque. The torque at which each clutch starts to slip is set initially at our facility but can subsequently be adjusted at any time. Ortlinghaus takes into consideration plate wear and changed conditions and compensates for there effects.



  • The inner hub of the friction clutch is normally located on the machine shaft with the aid of a keyway. There are many different possible ways of connecting the outer housing of the clutch to the adjoining machine components.