HOW A RETREAD IS MADE

HOW A RETREAD IS MADE

Retreading is the generic term for tyre reconditioning which extends the useful life of a worn tyre for its original purpose by the addition of new material.

In the majority of cases the tread rubber is the only part of a tyre to wear away. The structure of the tyre remains intact. As the tyre construction has been produced to be capable of more than one life, to use this potential by replacing the worn tread makes sound environmental and economic sense.

 

After INITIAL INSPECTION of the worn casing to judge its acceptability for processing, the remaining unwanted old tread is removed. This process is called BUFFING and it provides a profile and surface texture in preparation for the application of a new tread.

SECONDARY INSPECTION then takes place during which time any necessary correction work is carried out prior to continuation of the process.

The application of a new tread and sometimes sidewall veneer is the next stage. This is called the BUILDING process. There are two main ways of building a retreaded tyre. With the hot cure or mould cure process, uncured tread rubber is applied to the casing, usually using a strip-winding machine. In the cold cure or pre-cure method a pre-cured tread strip is applied to the casing. When the operator is satisfied that all criteria have been met the built tyre then moves on to the curing operation.

CURING or VULCANISATION can also be carried out in different ways. The hot cure process uses an individual curing matrix (known as a mould), similar to that used to cure new tyres. In the pre-cure process, however, the tyres are cured in an autoclave (curing chamber). Car tyres are retreaded exclusively using the hot cure process. Commercial vehicle tyres can be retreaded using either process. During the curing process the physical properties of the tread change and the newly applied material forms a permanent chemical bond with the existing casing.

After curing, a FINAL INSPECTION is made to rule out any defect which would impair serviceability or the safety of the user. Unacceptable tyres are rejected and scrapped.

 

 WHY USE A RETREAD

SAFETY **
*Retreaded Tyres are Safe!*

Retreaded tyres are manufactured to high standards using highly sophisticated machinery. Since January 2004 it has been a legal requirement for retreads to be manufactured according to ECE Regulations 108 (car tyres) and 109 (commercial vehicles tyres), which stipulates that tyres are tested to the same load and speed criteria as new tyres.

Although many UK retreaders had been producing according to ECE 108 and 109 for some time, the introduction of the regulations as a mandatory requirement has made a considerable contribution towards ensuring and proving that the quality, integrity and performance of retreaded tyres are, at the very least, on a par with that of new tyres.

ECONOMY **__
*Retreaded Tyres are Great Value for Money!*

Retreaded tyres can and do perform as well as tyres that have never been retreaded and they do it at a substantial savings over the high cost of new tyres.

It should be remembered that every major truck tyre manufacturer, with no exceptions, manufactures its tyres for multiple lives, meaning they are designed to be retreaded. So when an owner operator or a fleet manager doesn’t retread his tyres, he is simply throwing money away.

If you are a private car owner, retreads also offer a viable economic alternative to new tyres.

ENVIRONMENT **
*Retreads are Green!*

Retreading is highly environmentally friendly and should be considered as the best practical environmental option for tyre recycling. Unlike other forms of tyre recycling or disposal, retreading does not simply defer the eventual disposal of the tyre, but actively contributes towards reducing the amount of tyres being used and hence saving valuable natural resources.

Every retread produced means one less new tyre, thereby minimising the number of new tyres produced annually, extending the life of the original product and saving substantially on resources such as oil (a passenger retread requires 20 litres less oil than a new tyre. For a truck tyre this figure is 68 litres).

The result is less tyres to be disposed of annually. At the end of their first, second or even third life retreaded tyres can then be used as a raw material for other forms of ‘deferred disposal’. This is consistent with the Government’s sustainable development policy.


FREQUENTLY ASKED QUESTIONS

Does anybody actually use retreads?

Yes, nearly half the truck and bus tyres on the road in the UK have been retreaded and operate very safely. In fact, all the major tyre manufacturers without exception manufacture their tyres for multiple lives, meaning they are designed to be retreaded. Indeed many of them also operate their own retread plants in the UK.

Retreads are also used on passenger cars throughout the UK – not only for standard vehicles but for high performance vehicles and even for motorsport.

Retreads are also used in aviation and are retreaded many times. Every commercial airline uses retreaded tyres and in fact over 90% of all aircraft tyres are retreads.

Can you drive at normal speeds on retreads?

Yes, of course. The idea that retreaded tyres can not be used at normal road speeds is a complete myth. All passenger retreads (with the exception of a few specialist winter and off-road tyres) are speed rated at least to S (180 kmh – 112mph) and many are rated as high as V (240 kmh – 149 mph)

Can you use retreads in winter?

Absolutely. In fact, retreaded winter tyres have been particularly successful across Europe. If you are looking for extra safety in the winter weather but feel that switching to new winter tyres is too much of an expense, then why not use a set of winter retreads. They offer excellent performance and superb economy.

How can we be confident of the quality of retreaded tyres?

Retreaded tyres have been manufactured to the requirements of a British Standard (the BS au 144 series) for many years. However, two new EC Regulations relating to the “type approval” of retreaded tyres (ECE Rulation 108 for car tyres and 109 for commercial vehicles tyres) became mandatory in the UK with effect from January 1st 2004.

The two new Regulations, which identify uniform conditions for the approval of individual retreading facilities, effectively means that retread producers have effectively become ‘licensed’ operations, a move which is has made a considerable contribution towards ensuring that the quality, integrity and performance of retreaded tyres are, at the very least, on a par with that of new tyres.

What about all the rubber we see on the side of motorways. Doesn’t all that come from retreads?
No. This is just as likely to come from a new tyre. The fact is that the majority of tyre failures are the result of improper tyre maintenance. If tyres are not regularly checked for damage or under/overinflation there is a risk that they might fail and it doesn’t matter whether they are new tyres or retreads.