Repair manual

Keeping You On the Road 119
Curing Tube – Special, heavy duty tube placed
within the tire while curing.
Cushion Gum – A tacky rubber compound used for
adhesion, undertread repair, and build-up. (Also See
Precured Tread Cushion Gum).
Cut-off Rib – An indentation molded into a retreaded
tire to produce a sharp ending at the edge of the new
retread rubber.
Debagger – A device for inserting and removing
curing tubes.
Delugger – A machine used to cut the lugs from
tires prior to bufng.
Detreader – A machine that delugs and buffs a
used tire.
Die Size – A coded description of the dimensions
of tread rubber.
Extruder – A machine that shapes a rubber
compound, by the process of extruding, into a usable
form (i.e. strip or die size).
Fabric Fatigue – Fabric degradation and resultant
tire cord breakdown due to repeated exing.
Filler Strip – A free owing rubber used under the
tread when added thickness is needed.
Flow Stop – An indentation molded into a retreaded
tire to produce a sharp ending at the edge of the
new retread rubber.
Full Capping – Application of new rubber to the
tread area and some distance down the sidewall
of a used tire. Gives the appearance of a new tire.
Groove – Space between two adjacent tread ribs.
Groove Cracking – Cracking which occurs at the
bottom of a tread groove.
Heat Booster – An electric heating unit, which,
when placed between the airbag and the casing of
the tire, provides internal heat and aids in the curing
of the tire.
Kettle Cure – Cure method employing steam and air
for the heat and pressure required in vulcanizing.
Liner – The tubeless tire inner surface used to retain
the inflation media.
Lug Tearing - Rupture of the lug, sometimes
resulting in removal, resulting from violent operation
or mechanical interference.
Mandrel – A curved support inserted in a tire to
prevent the casing from collapsing while building
a repair.
Matrix – Aluminum or steel rings or segments
which form the cavity in which the tire is actually
cured and from which the tread design is formed.
Matrix Skirt – The sidewall flange of the matrix.
In a short skirt matrix the flange extends from the
shoulder to the flow stop and in a long skirt matrix
it extends below the ow stop.
Moisture Blows – Ply separations caused by the
presence of moisture in the carcass which, 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.
Mold Lubricant – Material used as a mold release
to facilitate removal of the tire from the mold after
curing.
Non-Fill – Failure of the tread rubber to properly ll
the matrix during cure, resulting in imperfectly formed
tread elements and rounded lug edges.
Open Splice – A retreaded tire defect caused by
failure of the rubber to knit together properly at the
tread splice during cure.
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 specied temperature.
Orbitread Machine – A combined tuber-builder
that applies tread rubber in ribbon form, and in a
spiral conguration.
Overall Diameter (O.D.) – A measurement used to
size a buffed tire. Usually made on an inated tire
using calipers or a diameter type rule.
Overcure – Vulcanizing longer than necessary.
Can result in the deterioration of certain physical
properties.
Overflow – Spew-out of tread compound at the mold
parting line or at the edge of the matrix skirt which
should be trimmed or buffed off the nished product.
Padding Gum – Heat resistant rubber used under
tread rubber to build up its size for mold t.
Peaking – A condition, usually in the cushion,
resulting from local material starvation and
excessive flow from adjacent areas.
Ply – A layer of rubber coated parallel cords.
Ply Separation – A parting of rubber compound
between adjacent plies.
Potentiometer – A milivoltmeter calibrated to
sense temperature in a desired range. (Usually direct
reading.)
Precured Tread – Tread which is vulcanized with
the tread conguration molded into it prior to being
placed on the buffed casing.
Precured Tread Cushion Gum – A tacky rubber
compound used to bond the precured tread to the
buffed surface.