Van, Truck, Trailer, Bus and Coach Aftermarket News in Ireland

CV brake discs – re-engineered to improve performance

It is now 20 years since the safety regulation, ECER90, was introduced for replacement disc brake pads and drum brake linings. The aim of ECER90 was to establish a common minimum standard of braking performance, product integrity and manufactured quality, for replacement brake linings across the whole of Europe.

Prior to the introduction of ECER90 the market was unregulated and products of dubious performance and quality could be sold with impunity with consequent safety risks to all road users.

The benefits of the regulation were quickly recognised outside Europe and as a result many other countries worldwide have also adopted this as their safety standard for replacement braking parts and consequently the regulation is now a UN regulation, not European and is now designated UNECER90

Once UNECER90 had been implemented and “bedded down” for brake linings, attention was turned to the other element of the braking couple, the brake disc and drum. These too are safety critical components with hitherto no regulatory standards to control their performance, integrity or manufactured quality.

A working group was therefore formed from experts at vehicle, and brake component manufacturers and government technical services across Europe, to develop an extension to UNECER90 to cover brake discs and drums.

The outcome of five years of vigorous discussion and testing finally resulted in the 02 series of amendments to UNECER90. The 02 series of amendments is now in force. It applies to replacement brake discs for trucks, buses and trailers, whose brake systems were type approved after 1/11/2014.

Whilst brake discs for vehicles first type approved before this date do not need a legal approval there is clearly merit for the customer in showing that the whole of the range of brake discs that you provide meets the legislative requirements and safety standards which is why more than 95 per cent of Juratek’s range of CV brake discs are now UNECER90:02 approved

The approval for replacement brake discs and drums follows the same general concept as for replacement brake linings; there are performance tests to check that the replacement part meets the requirements of Regulation 13– this is the braking regulation that all new vehicles must meet before they can be sold on the market. Then there are Structural Integrity tests. These tests, in particular the Thermal Fatigue test, really lie at the heart of UN ECER90:02 for replacement brake discs and drums and are designed to ensure that replacement parts at least match the capability of OE parts in dissipating high levels of braking energy without excessive cracking or structural failure.

As with brake linings replacement brake discs and drums will carry the “E” approval mark which will be of the following general form (for example) E11 02 C 0359 7248”, “E11” indicating approval by the UK.

This extension to UNECER90 is welcome. Like brake pads and linings, brake discs and drums are safety critical parts, and the extension of the regulation will help ensure that only replacement brake discs of a high level of quality are sold and used, and that can only be of benefit to all owners, operators and road users.

In addition to the exacting standards imposed by the UNECER90 regulations, Juratek also looks for ways to improve on existing OEM design. For example the latest version of the DAF111D is a case in point. The original design consists of a complicated fitting kit to attach the braking ring to the hub. So as not to infringe on the original patented design, Juratek have re-engineered the disc. There are several other suppliers offering a different version, but Juratek’s version differs significantly.

One of the main issues with the various aftermarket versions is that the discs fits on the same mounting surface as the original, which sounds logical, however the hub can wear over time, so fitting a new disc to a worn hub can still cause service issues. In order to address this issue, the Juratek engineers have designed their version to fit on a different plane of the hub. When fitted to a new or un-worn hub the fit is perfect, however the design really shows its advantage when fitting to a worn hub as the surface it is now being fitted to has previously been free of wear. So again the fit is perfect. The obvious advantage to this design then is the savings from having to replace a worn hub, which can typically be around £500 per hub, thus giving the transport industry real value for money.