Timing belts catalogue
A complete range of high performance timing belts for cars.
Number of references in range: 433
Reference example: 136 HTDP 25
A vital part
Synchronous belts began to appear in car engines in the 1960s. At that time they were used in several branches of the industry for the manufacture of vehicles allowing transmission of power or synchronous commands. Running alongside the development of the automobile, the timing belt began to make its mark as a central element in the operation of both petrol and diesel engines.
The main job of the timing belt is to regulate injection, by driving the camshaft and injection pumps on opening and closing of the valves. In some drivetrains, it also drives the water pump, oil pump and other accessories. The proximity of the engine and the mechanical constraints to which they are subject give us a very high set of technical specifications. Their composition and structure must therefore be adapted to each type of engine and each drivetrain.
With the development of engine technologies, "downsizing" and increased power, manufacturers have encouraged us to develop belts that are increasingly resistant to extremes of temperature in the engine compartment (from -30° to +130°C) and to climate variations (drought, humidity, ozone). We have also reduced their noise levels through the use of shock-absorbing fabric and material. The aim has always been to guarantee safe operation of the timing belts and to gradually lengthen their lifetime. Thus, some timing belts have a lifetime of 250,000km according to the manufacturer specifications.
The internal structure of the timing belts is made up of an elastomer, a fibre glass casing and a polyamide fabric.
The elastomer makes up the back of the belt and forms the teeth. These elastomers were chosen for the stability of their mechanical properties at high temperatures, as "HNBR" (Hydrogenated Nitrile Butadiene Rubber) is, in this respect, even more efficient than "CR" (polychloroprene).
Buried in the elastomer is the fibre glass casing (known as "wiring", which has the property of having a high stiffness value. This makes it possible to guarantee the rigidity of the timing belt along its length and to ensure that its length is maintained.
The polyamide fabric covers the teeth. Its purpose is, on the one hand, to give the tooth its shape during the vulcanisation of the elastomer, and, on the other hand, to strengthen it and protect it against wear. The manufacture of these belts takes place by transferring the elastomer via the layer of wires during vulcanisation in the mould.
The profile and course of the timing belt teeth changes depending on the type of engine and the course of the teeth. In cars, there are three main types of teeth profile: trapezoidal, HTP (High Torque Drive) or parabolic. The profiles of Hutchinson timing belts are identifiable in the commercial reference of the belt according to the following classification:
Example: 136 HTDP 25