Tire Plugs

A tire was found with a plug in the sidewall as a repair with no patch or other reinforcement. Is this a recommended practice and should it be allowed. There is currently nothing in the OOS criteria to address this situation.

The Tire and Wheel Study Group from TMC was contacted and the response from them was as follows: NO!! This is not an acceptable practice. Any puncture/damage in the sidewall must be treated as a section repair. A section repair requires that uncured rubber be applied to the finished injury, it must be heat cured, and a repair unit must be installed on the inside. Further, plugs inserted into the tire from the outside are never acceptable anywhere in the tire. It is very common to find these in the tread, however, these are not acceptable either. All tires that are to be repaired, must be: Demounted from the rim, carefully inspected on the inside to ensure that there is no further damage inside the tire, the injuries must be filled with either uncured rubber or a rubber plug, a repair unit must be installed over the injury on the inside of the tire. It is very common to find rubber coated \"string\" repairs shoved into the tire from the outside to fill the hole. I have seen relatively large repairs made that required at least a dozen rubber strings to fill the hole. These are tire failures waiting to happen and it is not uncommon for them to be the cause of accidents. People use this repair material because it is cheap and fast since the tire does not have to be demounted. The tire industry does not approve at all of these repairs. I think it would be good to consider making these repairs an out of service condition.

It is recommended that tires in this condition should be placed OOS. Here is the recommended language for the OOS condition. Rubber coated cord or cured rubber plugs are used to fill the hole with no repair unit reinforcing the injury on the interior.