Automatic torque limiters perform when it counts

Italian company Bondioli & Pavesi manufactures a large range of clutches to provide security and safety to heavy machinery.

The range includes friction disc models, overrun models, combined friction and overrun models, sheer bolt models and LR series automatic torque limiter models.

BYPY Transmissions is the distributor of Bondioli & Pavesi clutches in Australia, and BYPY manager Richard Baker says the automatic torque limiter is the top of the line in clutch technology.

"Torque limiters have the ability to interrupt the transmission of power in the event of torque peaks that exceed a preselected setting. Once the driveline has ceased rotating and the obstruction that caused the overload is removed, the torque limiter automatically re-engages," Richard Baker says.

"LR series torque limiters can be fitted to a variety of shafts, depending on the power being transmitted. They can be used to provide protection from torque overloads on any machines where safety and time are vital. This includes machinery used for drilling, boring, or conveying and a wide variety of agricultural implements including rotary hoes, power harrows, balers, feed mixers and slashers.

"While automatic torque limiters are more expensive than other types of clutches, farmers and other professionals know that it is not the cost or a part but serious downtime that is the highest cost they face. The time saved should something goes wrong more than compensates for the additional cost of an LR series clutch."

Generally an automatic torque limiter is set to disengage at twice the median torque peak. The LR clutch is usually located as close as possible to the driven load.

They are designed to operate in one direction only, usually anti clockwise rotation. Special versions are available for clockwise rotation, however.

The LR clutch is securely attached to the driven shaft by means of a tapered bolt. The operator tightens it to the correct torque rating before using the machine.

Richard Baker says the LR clutch is also available as a combined overrun/automatic torque limiter.

Maintenance is simple. It requires annual inspection only, and using a special lubricant that will not throw off the internal components so a long life is ensured.

To alter the preset torque settings is as simple as replacing the internal spring pack. The spring packs are available from, 1200 to 5000 Nm.

Recommended torque settings:

150 Nm for Tapered Bolts 1 " Z6 or Z21

220 Nm for Tapered Bolts 1 " Z6 or Z20

Richard Baker says operators should always be aware of rotating shafts, and always disconnect them from the power source prior to carrying out maintenance.

For further information and assistance contact BYPY Transmissions on 1800 033 793 or e-mail

BYPY Transmissions means professionals in motion.

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