TM 9-2610-200-14
E-4
APPENDIX E: GLOSSARY (Con't)
Lug Tearing
Rupture of the lug, sometimes resulting in its removal, caused by violent
operation or mechanical interference .
Mandrel
A curved support inserted in a tire to prevent the casing from collapsing
while building a repair.
Moisture Blows
Ply separations caused by the presence of moisture in the casing that,
when subjected to heat, becomes steam and expands.
Mold
Equipment in which the new tread is cured to the worn tire. Mold
includes the steam chamber, matrix, and adjusting devices.
Optimum Cure
That state of cure at which the rubber compound exhibits the most
satisfactory physical properties. Usually expressed in minutes curing time
at a specified temperature.
Overbuff
Removal of too much material by buffing. Buffing an area too large for
reinforcement patch or die size of rubber to be used .
Overcure
Vulcanizing longer than necessary .Can result in the deterioration of
certain physical properties.
Ozone
Active form of oxygen, usually caused by static electricity, that is very
harmful to rubber. Causes checking and cracking often attributed to aging
or weathering.
Ozone Resistant
A formulation of rubber resistant to the cracking effect of ozone in the
atmosphere. Although the ozone resistance of natural rubber is poor, it
can be improved by compounding with anti-ozone chemicals and waxes.
Pinholes
Minute circular voids in cured or uncured rubber.
Plug
A piece of new rubber vulcanized into tread or sidewall injury.
Ply
A layer of rubber coated parallel cores, several of which, laid one across
the other, make up the casing of the tire.
Ply Separation
A parting of rubber compound between adjacent plies.
Potentiometer
A multivoltmeter calibrated to sense temperature in a desired range
(usually direct reading).
Premature Vulcanization
Uncontrolled curing or setup (loss of flow qualities) in material before
final cure.
Pyrometer
An instrument to measure temperatures. usually by the generation of
electric current by a thermocouple when acted on by direct heat.
Commonly used to measure surface mold temperatures or, if a
penetrating needle is used, tread rubber temperatures.
