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Power Transmission

We off­er expert advice for power transmission, whether it is belts, pulleys, chains, couplings, sprockets, gears or electric motor drives. We have decades of experience allowing us to provide unparalleled support and advice, and we supply globally recognised brands.

What is Power Transmission?

Power transmission, in its simplest form, is the transfer of energy from one place to another. Mechanical power is transmitted using a few basic systems - driveshafts, gears, belts, chains, hydraulic systems or pneumatic systems.

Driveshafts can carry extremely high loads with almost 100% efficiency, which is one of the reasons they are ubiquitous in automotive and transport applications, but they do have disadvantages. The shaft is often heavy and because it is mechanically coupled to the motor it transmits vibration from the motor to the rest of the equipment. They also require lubrication and maintenance.

Gears are also capable of carrying high loads but suffer some of the same disadvantages as a driveshaft, such as vibration transmission and the need for lubrication and maintenance. In addition, they struggle to transmit power over long distances as the cogs must be in contact.

Power Transmission Belts

Drivebelts solve many of these problems. They are looped over pulleys and transmit power between those pulleys; they are also used to transmit position information (typically using toothed belts) to synchronise different parts of equipment.

They key advantages of using belts for power transmission are low weight, high efficiency, low vibration transmission, low maintenance and protect against overload and jam. They are often the best way of transmitting power between shafts that are not axially aligned. Load fluctuations are shock absorbed, so both the motor and the target pulley are cushioned.

Flat belts are still used but it is much more common to use V-belts or toothed belts.

Despite being called ‘V’ belts, they are actually trapezoidal in cross section. They self-centre and, and power increases, they wedge further into the V groove of the pulley which increases torque.

Toothed belts have teeth on the inside side, and these teeth fit into matching teeth on the pulley. They don’t slip, they run at constant speed, and as well as power transmission they also excel at timing or indexing.

Belt Maintenance

Belt drives rely on friction to operate (though less so for toothed belts). However, friction wastes energy and causes belt wear. This can be mitigated by correctly tensioning the belt and making sure it is operating at the correct angle.

Power transmission depends on belt tension, but increasing the tension also loads the bearings which reduces their life. Toothed belts are able to transfer power with higher efficiencies at lower tensions.

Belts do wear, but most belt failure is due to fatigue which is caused by the belt rolling round the pulley. Belts suffer from fatigue faster at higher loads and tensions, so again toothed belts have an advantage.

Power Transmission Support

We stock world leading brands such as Bando and Elatech, with a vast range of different belt types, technologies, lengths and widths. Talk to us about the belt products we can supply and the support we can offer.

Power Transmission