Cable
yarn:
Two or
more plied yarns twisted together.
Calculated
center distance:
In belt
drives, the distance between two shaft centers calculated from pulley diameters
and belt length being used.
Calender:
A
machine with three or more internally heated or cooled cylinders used to (1)
continuously sheet out polymeric compound or fused PVC (2) to wipe polymeric
compound into the interstices of a fabric leaving a small portion of it on the
surface of the fabric, or (3) to lay a continuous sheet of compound on a fabric.
Calendered
"rubber" sheets:
Continuous
film of uncured elastomer produced from a calendar.
Camber:
The
curvature of a belt relative to the center line (see bow).
Capacity:
The
maximum number of pieces, volume, or weight of material a belt conveyor can
handle in a given time interval and belt speed.
Capped
edge:
A rubber
protective edge placed around a product internally reinforced with textile or
other material.
Capped
end:
A belt
end covered with an elastomer to protect the carcass end.
Carcass:
The
fabric, cord and/or metal reinforcing section of any rubber product such as a
belt, as distinguished from the rubber cover.
Carcass
break:
A ply or
plies of fabric ruptured by impact or gouging.
Carcass
tear strength:
The
resistance of a belt against tearing.
Carcass
tear test:
The
determination of the tension at which a belt may be torn.
Carrier:
See
idler (2).
Carry
(or carrying) side cover:
See top
cover.
Carrying
roller:
See
carrying idler.
Carrying
run:
The
portion of a conveyor that carries the load between the loading and discharge
points.
Carrying
surface:
The
outward face or side of the belt which carries the conveyed material.
Castfilm:
A film
made by depositing a layer of plastic, either molten, in solution, or in a
dispersion onto a surface, solidifying and removing the film from the surface.
Catenary
idler:
A type
of flexible belt-carrying idler with ends supported in pivoted stands. The
tube or rollers sag under the weight of the load to form trough.
CEMA:
Conveyor
Equipment Manufacturers Association.
Cement:
A
mixture of polymeric compound or elastomer used as an adhesive or sealant.
Cemented
edge:
An
application of cement around the edge of a fabricated product with or without
internal reinforcement for protection or adhesion. (A form of Capped Edge.)
Cemented
end:
A belt
end sealed with the application of elastomeric cement.
Center
roll:
The
horizontal roll between the side troughing rolls.
Center-to-center:
The
distance between the center of two pulleys or idlers. Also called centers
or center distance.
Centrifugal
bucket elevator:
A type
of bucket elevator having a belt which travels at sufficient speed to discharge
material from the buckets by centrifugal force.
Chafer
duck:
A
relatively open weave duck of approximately square woven construction made with
single or ply yarn.
Chalking:
Formation
of a powdery surface condition due to disintegration of surface binder or
elastomer due in turn to weathering or other destructive environments.
Checking:
Short
shallow cracks on the surface generally due to effect of destructive action of
environmental conditions.
Chevron:
A ridge
or profile arranged in a Vee shaped configuration on a belt carrying cover to
stabilize material carried up an incline.
Chute
lining:
Highly
abrasion resistant elastomeric lining in a chute to protect the metal chute from
abrasion wear.
Chute
slope:
Angle
relative to the horizontal a chute is inclined.
Cleated
belt:
Transverse
raised sections on a conveyor belt to stabilize material carried up an incline.
Closed
belt conveyor:
A
moving, endless conveyor belt formed into a tubular shape by joining its edges
while carrying material, and opening the edges while in motion to receive and
discharge material.
Cloth
impression:
See
fabric impression.
Cluster
end:
A flat
disc idler with several discs adjacent to each other at the ends of the idler.
Coefficient
of friction:
The
ratio of the force required to move a package across a belt surface to the
weight of the package.
Cog:
A tooth
on the rim of a wheel or rubber product.
Cogged
V-belt:
A V-belt
cut or produced with a series of evenly spaced V-shaped indentations in the
inner face to increase the belt's flexibility.
Cohesive:
Tendency
of a material to stick to itself.
Coil:
Usually a squared end belt piece of full manufacturing length but not
full manufacturing width. See also slab belting.
Cold
feed:
The
introduction of plastic pellets into processing equipment without milling.
Cold
flex:
See low
temperature flexing.
Cold
flexibility:
The
relative ease of bending following exposure to low temperature.
Cold
flow:
Continued
deformation under stress. See Creep.
Cold
splice/bond:
Usually
the joining of two or more sub-straits together, using a two-part cement that is
chemically cured without using supplemental heat from an external source.
"Cold
bond cement" usually is an uncured mixture of varied elastomers, chemicals,
and solvents that will not self-cure or vulcanize until mixed with an activator
to create a chemical vulcanization (usually exo-thermic).
Commercially
smooth:
A degree
of smoothness of an article which is acceptable in accordance with industry
practice.
Compound:
A
mixture of a polymer(s) and other materials to give the desired chemical and
physical properties in the elastomeric components of a belt.
Compression
member:
The
portion of a belt beneath the pitch line as the belt bends around a pulley.
Compression
set:
The
deformation in a material remaining after it has been subjected to and released
from a compressive force.
Conductivity:
Quality
of power of conducting or transmitting heat or electricity.
Contact
stain:
When
staining occurs on the area of an object directly in contact with the rubber
article it is known as "contact stain".
Continuous
bucket elevator:
A bucket
elevator belt that discharges by gravity over the inverted bottom of the
preceding bucket on the descending side of the elevator.
Control:
A
material or a product of known characteristics included in a series of tests to
provide a basis for evaluation of other products.
Conveyor:
A system
for the continuous movement or transport of bulk materials, packages or objects
along a predetermined path.
Conveyor
belt:
A belt
that carries materials from one place to another.
Conveyor
belt package deflector:
A
mechanical diverter placed at an angle across the belt to deflect packages off
the belt at specific locations.
Conveyor
belt stretch:
The
increase in belt length which occurs when tension is imposed. Stretch is
either elastic or permanent. Elastic stretch is a temporary change in length
which varies directly with the pull. Permanent stretch is the residual change in
length after tension has been removed; it generally accumulates over a period of
time.
Conveyor
width:
In belt
conveyors, the width of a belt.
Copolymer:
A
substance consisting of molecules characterized by the repetition of two or more
types of monomeric units.
Cord:
Several
strands of yarn twisted together.
Cord
belt:
A belt
with inserted textile or steel cords for the longitudinal tension-bearing member.
Cord
fabric:
A fabric
with plied or cabled yarns in the warp direction and a light weight filling yarn
spaced only sufficiently to process the fabric.
Cotton:
A
natural fiber of high cellulosic content.
Count:
In a fabric, the number of warp ends, the number of filling picks, or both in a
square inch of fabric.
Counter
weight:
In
conveyor belting, the weight applied to the take-up assembly to maintain proper
belt tension.
Cover:
The
outer component of a belt.
Cover
seam:
See
cover splice.
Cover
splice:
The
transverse joint formed by connecting two lengths of cover stock.
Cover
surface profile:
A
cross-sectional view of the cover surface.
Cover
wear:
The loss
of material during use due to abrasion, cutting or gouging.
Cracking:
A sharp
break or fissure in the surface. Generally due to excessive strain.
Crater:
A small
shallow surface imperfection.
Crazing:
A cover
surface with many fissures.
Creep:
(1) The
deformation occurring with the lapse of time in both cured and uncured rubber,
in a body under stress in addition to the immediate elastic deformation. Some
related terms and properties are stress-relaxation, hysteresis, damping, flow,
compression set and viscosity. See Cold Flow. (2) In belts, the action of a belt
alternately losing speed on the driving pulley and gaining speed on the driven
pulley.
Creeper
drive:
An
auxiliary drive, usually consisting of a small motor and speed reducer, used to
keep a belt conveyor in motion at a very low speed during non-operating periods
in extremely cold weather. It is used to prevent freezing of a belt and
other components.
Crimp:
(1)
The waviness of the yarn in a woven fabric. (2) The difference in distance
between two points on a yarn as it lies in a fabric and the same two points when
the yarn has been removed and straightened. Expressed as a percentage of
the distance between the two points as the yarn lies in the fabric.
Crown:
The
difference between the diameter at the center and at the edges of a pulley or a
roll.
Crowned
pulley:
A pulley
with a greater diameter at the center, or other points, than at the edges.
There are radial and trapezoidal crowns. Apex crowns are not
recommended for industrial belts.
Crystallization:
A change
in physical properties resulting from the crystalline reorientation caused by
temperature.
Cure:
The act
of vulcanization.
Cure
time:
Time
required, at a given temperature, to produce optimum physical properties in an
elastomer.
Curing
temperature:
The
temperature at which the rubber product is vulcanized.
Curl:
The
action of the edges of a belt bending upward on the carrying run and downward on
the return run. Also called cupping.
Cushion
breaker:
A leno
or cord breaker imbedded in a belt cover.
Cut
belts:
See cut
edge.
Cut
edge:
The
uncovered edge of a laminated product, such a belt, created by cutting after
vulcanization.
Cut
resistance:
The
ability of a belt cover to withstand the cutting action of sharp objects.
