Tire Cut Repair

Systematic and conscientious preventive maintenance of a tire’s work environment
provides a solid foundation for economical tire service. It is, however, understood that
damage to tires will occur and cannot be totally eliminated. Once damage occurs, steps
should be taken to repair the damage. Situations to consider are:

1. Punctures and Rock Penetration Å These situations require immediate tire
removal.
The tires should be inspected to determine the extent of the damage and the
possibility of repair. If the tire is determined to be repairable, it should be sent to a
qualified repair installation for further inspection and the necessary repairs.

2. Cuts -- The extent of the damage determines what course of action should be
followed.
It is important to remember that although a cut may not require immediate
removal, if left unattended it can lead to eventual failure of the tire. Cuts are
classified as follows:
a. Tread surface cuts not extending into the carcass.
b. Cuts through tread penetrating into or through the carcass.
c. Sidewall cuts.

3. Cut Through Tread -- If the damage is severe enough, it could lead to premature
tire failure. When it is determined that the tire has been damaged, the tire should
be immediately removed from service and sent to a qualified repair facility. The
three general repair classifications are:

a. Spot Repairs -- are for penetrations normally no deeper than 1/4 or less of
the total carcass. After removal of damaged material, the skived opening is
filled with repair rubber and cured to make the repair.


b. Reinforcement Repairs -- are for cuts that penetrate more than 1/4 but
less than 3/4 of the tire plies. In such cases, strength must be reinforced.
Fabric repair material is used to reinforce the tire and then repair processes
similar to those used in spot repairing are followed to complete the repair.

c. Section Repairs -- are for cuts that penetrate more than 3/4 of the plies
and completely rupture the casing. This often requires a reinforcing patch
on the inside of the tire and additional repair materials placed in the cut
from the outside. Repair rubber is again used to replace what has been
removed.


4. Sidewall Cuts -- Sidewall cuts are repairable, depending on the location and
extent of the damage. Mining personnel at the repair facility will determine after
inspection if a successful repair can be made.

5. Loose Rubber -- Loose rubber from a snag or cut should be removed from a tire
to prevent further damage.