Page 22 - CTB N14 - 2016-02

TYRE REPAIR
CommercialTyre
Management
and Fleet Business
Tyre Repair - Minor Tread Injuries –
Plugging v the Permanent Vulcanised Tyre Repair
Many countries in Europe do not have tyre repair standards which equate or stand up to the official accreditation BS AU159g 2013 that exists in Great Britain. This statute is the recognised and
being a tyre repair, they are referred to as a Temporary Seal, a means to be able to drive the vehicle at low speed to the nearest tyre repair service centre. The British Standard makes it clear to
any secondary damage that may have resulted from either the original penetrating object or from running the tyre in an underinflated state.
Minor Tread Area Penetrations
Under the standard a minor penetration repair is referred to as a crown or tread injury
maximum 6 mm for passenger car, and a maximum of 10 mm for commercial vehicles. However, it should be noted that a 10 mm minor repair is limited to 50% of the nominal section width of the tyre. (25%
each side of the tread centre line) Penetrating rubber on minor repairs are not permitted in sidewall or shoulder areas.
Once the tyre has been thoroughly inspected, the liner is cleaned within the damaged area. Normally a Liquid Buffer or a Fast Dry Buffer is applied to the repair area inside the tyre, then immediately scraped and vacuumed to remove all traces of silicone and other mould lubricants.
A probe is placed inside the injury to assess the angle of the penetration, maximum 15˚ off the perpendicular is possible with a Combi unit. (Combination of a stem and patch – sometimes referred to as a Mushroom repair unit)
Above 15˚ to a maximum angle of up to 25˚, a pre cured stem is often used to seal the penetration before the application of a separate rubber only or reinforced patch unit.
REMA TIP TOP Minicombi repair.
Following the full inspection of the tyre the appropriate rotary mill cutter is used to mill out the injury, starting from the inside of the tyre. The angle of the injury is followed as close as possible, then a reverse cut is performed from the outside of the tyre. This reversing of the milling procedure will remove all rust or damage from the injury area, leaving it clean and clinical for further repair material to be inserted. The liner area is now buffed using a low speed encapsulated wire brush. All buffing dust should be removed by vacuum.
REMA TIP TOP Fast Dry Cement is placed inside the penetration and to the buffed liner area inside the tyre.
Following the drying time, the
approved standard which regulates tyre repair material and repair procedures.
Plugs inserted into the tyre externally are not recognised as
accomplish a repair the tyre must first be removed from the wheel or rim, then thoroughly inspected from both the inside and out. This inspection should root out
22 Commercial Tyre Business