New TH technology Valeo clutch disc

Sets containing this type of discs are produced for first assembly line of heavy duty vehicles and buses manufacturers. They are also available on the aftermarket.

New TH technology discs can be currently found in 3 clutch kits available on the aftermarket. Two of them are applicable to Scania buses and coaches, the third one is applicable to Renault and Volvo trucks.

A very specific race has been going in Europe for over 25 years. The race of manufacturers of trucks and buses and the European legislator, introducing more and more demanding emission standards.

Since 1993, the European legislator has been introducing more and more strict emission standards on harmful substances, including in particular nitrogen oxides, hydrocarbons, carbon oxides and particulate matter. The role of truck manufacturers is to construct and improve trucks already available on the market so that they are able to meet these standards.

At the same time, another race is taking place. The race between truck manufacturers on the maximum reduction of fuel consumption. It is estimated that the cost of diesel oil constitutes more or less 40% of the costs of running of a transport company. Therefore, the choice of a truck by transport company is first and foremost predetermined by fuel consumption.

How does Valeo contribute to reducing fuel consumption and meeting emissions standards? The answer is – the new generation TH clutch disc.

Engine down-speeding is one of the most important ways of improving fuel economy and reducing CO2 emissions. Unfortunately, it also increases torque and vibrations that can induce noise and even damage the gearbox. There appears a dilemma: torque (power) vs vibrations. The lower the rpm, the higher the vibration.

To solve this dilemma, Valeo has developed the TH disc, a breakthrough damper technology. TH disc is able to increase the dampening performance by 30% comparing to TG disc, while transmitting a torque up to 3500 Nm (depending on the application). This allows the reduction of the engine speed by up to 200 RPM, which translates into fuel savings of even 3%.

How it is possible? To achieve this, damper diameter was increased from 254 to 285 mm (comparing to TG technology). What are the benefits of the larger damper diameter? It allows higher filtration by transferring torque up to 3 500 Nm (depends on application). At the same time the level of vibration and noise. In some cases allows even the avoidance of DMF application.  

The angular range of work of the TH damper is broader by 20 degrees. This allows optimization of vibration filtration. New spring seat bed (Valeo patent): limits springs torsions, increases reliability of the whole system.

Pre-dampers are well-known from the previous technology of TG discs. They ensure working comfort on neutral gear. The TH technology is characterised by lower spring stiffness. Damper stiffness gets lower with TH technology to enable optimized dampening. For the same engine torque, the stiffness will be much lower for TH damper compared to previous generations.

Let’s have a look at the friction material. The surface of the friction material of a TH disc is smaller than the surface of a TG disc. This has no negative effect on the clutch operation. Valeo always uses the same friction material, regardless of whether the clutch is to be the original equipment of the truck or produced for aftermarket. O.E. quality friction material ensures high heat resistance and reduces clutch juddering. New groves design (Valeo patented) in the TH type improves the coefficient of friction.

Owing to its extra-ordinary ability of vibration dampening TH discs are perfect for trucks and buses equipped with robotized gearboxes. So they are perfect for cases where the main requirement for the clutch designer is the ability of effective vibrations damping at low rpm, not high heat resistance.

The popularity of trucks with robotized gearbox has been growing rapidly recently. Valeo engineers have predicted this trend and thanks to this, Valeo offers truck manufacturers a new generation of TH clutch discs as original equipment for Euro 6 vehicles, and in the future also for Euro 7 vehicles.

From now on these products are also available on aftermarket. It is worth mentioning that Valeo clutches for trucks and buses are covered by a two-year warranty period in Europe with no mileage limit.