Glossary of Terms

Glossary of Common Terms

Abrasion resistance	Resistance of a material to abrasion.
Ambient Operating Temperature	Temperature of the medium surronding an object; for example, a belt at room temperature.
Centerline circle	Distance around the centerline of a belt, same as centerline circumference (figure 3).
Centerline circumference	Distance around the centerline of a belt (figure 3).
Centerline diameter	Distance from cross sectional center of one side of a belt through center point to cross sectional center of belt on opposite side (round: figure 1), (flat: figure 2).
Circumference	Distance around a circle (figure 3) Belt circumference must be specified as inside, outside or centerline circumference.
Coefficient of Friction	A term which represents the friction between two surfaces
Compression set	Difference between the thickness before compression and after compression, reported as % at duration and temperature.
Conductive	Material will conduct. Can refer to electricity, static electricity or heat.
Connectable belt	Usually refers to a repair belt which is used to temporarily replace failed live roller conveyor belts also known as a PC Belt (Pyramid’s Brand), quick fix, zero down time, twisted belt or band, temp belt or band as well as under other names.
Copolyester Elastomer	Plastics with the combined strength and processing characteristics of engineering plastics with the performance of thermoset elastomers.
Cross section	Describes the dimension across the outside of a belts section. Round belts will have one dimension, if concentric, and flat belts will have both a thickness and a width and a width.
Cut length	Length of a belt if it were cut and laid out straight (mathematically the same as centerline circumference or pitch circumference).
Diametape	Flexible, graduated tape used for nondestructive measurement of inside diameter and inside circumference of round or flat belts.
Diameter	Distance from one side of a circle through center point to opposite side of circle (round: figure 1), (flat: figure 2).
Dissipative	Neither conductive nor insulative, but dissipates Can refer to electricity, static electricity or heat.
Drive band	Another name for belts used to transmit rotational driving force from a source to driven object.
Drive belt	Belts used to transmit rotational driving force from a source to driven object.
Drive Shaft	This could describe a motor shaft but more often is used to describe a shaft which receives rotational power from the motor via gears, chain or belts and then transmits or distributes that power to other devices or equipment.
Durometer	Hardness of an elastomeric material, reported as a value on Shore A or Shore D scale.
Elastomeric	Stretchable, compressible rubber-like material.
Elongation	Distance a product a has been stretched, reported in %.
Flex fatigue	Failure due to repeated flexing.
Free length	Length of a belt when laid out straight and measured end to end (equivalent to Pitch circumference or Centerline circumference).
Glass transition	Temperature at which a material loses its glass-like properties and becomes elastic.
Hygroscopic	Ability of a material to absorb moisture.
IC	Inside Circumference (figure 3).
ID	Inside Diameter (round: figure 1), (flat: figure 2).
Inside circle	Distance around the inside surface of a belt, same as inside circumference (figure 3).
Inside circumference	Distance around the inside surface of a belt (figure 3).
Inside diameter	Distance from inside surface of a belt through the center point to opposite inside surface of the belt (round: figure 1), (flat: figure 2).
Insulative	Material will not conduct. Can refer to electricity, static electricity or heat.
Modulus	Elastic materials resistance to elongation (tension), reported in PSI.
Modulus decay	Reduction of modulus (tension) over a given time, reported as % loss at duration or PSI loss at duration.
N.I.S.T.	National Institute of Standards and Technology.
Non-conductive	Material will not conduct. Can refer to electricity, static electricity or heat.
Non-reinforced belt	Elastic belt with no fiber reinforcement embodied within the body.
Non-supported belt	Elastic belt with no fiber reinforcement embodied within the body.
O-bands	Name for a drive belt which is derived from the use of O-rings as makeshift drive belts, also known as O-belt, O-ring belt, O-ring drive belt, etc.
O-belt	Name for a drive belt which is derived from the use of O-rings as makeshift drive belts, also known as O-ring belt, O-ring drive belt, O-band, etc.
OC	Outside Circumference (figure 3).
OD	Outside Diameter (round: figure 1), (flat: figure 2).
O-ring	Elastomeric ring developed to be used as a seal to prevent fluid leakage and at times substituted for a drive belt.
O-ring belt	Name for a drive belt which is derived from the use of O-rings as makeshift drive belts, also known as O-belt, O-ring drive belt, O-band, etc.
O-ring drive belt	Name for a drive belt which is derived from the use of O-rings as makeshift drive belts, also known as O-belt, O-ring belt, O-band, etc.
Outside circle	Distance around the outside surface of a circle or belt. Same as outside circumference.(figure 3)
Outside circumference	Distance around the outside surface of a circle or belt (figure 3).
Outside diameter	Distance from outside surface of a circle through the center point to opposite outside surface of the circle (round: figure 1), (flat: figure 2).
PC belt	Connectable repair belt manufactured by Pyramid Inc. which is used to temporarily replace failed live roller conveyor belts.
PD	Pitch Diameter (round: figure 1), (flat: figure 2).
Pitch circumference	Distance around the centerline of a belt (figure 3).
Pitch diameter (belt)	Distance from cross sectional center of one side of a belt through center point to cross sectional center of belt on opposite side (round: figure 1), (flat: figure 2).
Pitch diameter (pulley)	Distance from cross sectional center of one side of a belt that will be used in pulley, through center point to cross sectional center of belt on opposite side (round: figure 1), (flat: figure 2).
Pitch length (application)	Distance around the center of the belt when installed on the application.
Pitch length (belt)	Distance around the center of the belt. Same as free length and centerline circumference.
Polyester based PU	Most commonly used polyurethane with excellent physical properties and moderate pricing.
Polyether based PU	Polyurethane with improved resistance to combinations of elevated temperatures and high humidity at somewhat higher pricing.
Polyurethane	A high grade plastic with better abrasion, cut, impact, and tear resistance than rubber or many other plastics. Also known as Urethane.
PSI	Pounds per Square Inch of area.
PU	Abbreviation for polyurethane or urethane.
Pulley	Wheel used to transmit power by means of a belt passing over its rim, usually within a groove. Groove configurations vary depending upon type of belt used and include “v” bottom, round bottom (sometimes called u bottomed) or flat bottom (with or without flanges).
Pyrathane®	Pyrathane® is Pyramid’s registered trade name for the polyurethane products offered.
Quick fix belt	Usually refers to a repair belt which is used to temporarily replace failed live roller conveyor belts. Also known as a PC Belt (Pyramid’s Brand), quick fix, zero down time, twisted belt or band, temp belt or band as well as under other names.
Resins	Viscous liquid materials capable of hardening.
RPM	Revolutions Per Minute.
Shore Durometer	Hardness of an elastomeric material, reported as a value on Shore A (softer) or Shore D (harder) scale.
Specific gravity	Weight of item related to water, reported as a %.
Splice	Joining two pieces, or ends of cord, together.
Tear strength	Force required to propagate a tear in a direction perpendicular to the direction of elongation, reported in PSI.
Temp belt or band	Usually refers to a repair belt which is used to temporarily replace failed belts. Also known as a PC Belt (Pyramid’s Brand), quick fix, zero down time, twisted belt or band as well as under other names.
Temporary belt or band	Usually refers to a repair belt which is used to temporarily replace failed belts. Also known as a PC Belt (Pyramid’s Brand), quick fix, zero down time, twisted belt or band as well as under other names.
Tensile modulus	Elastic materials resistance to elongation (tension), reported in PSI at a given elongation.
Tensile strength	Force required to break an object by stretching, reported in PSI.
TPE	Thermoplastic Elastomer.
TPU	Thermoplastic Urethane.
Twisted belt or band	Usually refers to a repair belt which is used to temporarily belts. Also known as a PC Belt (Pyramid’s Brand), quick fix, zero down time, temp belt or band as well as under other names.
Twisty Belt or band	Usually refers to a repair belt which is used to temporarily belts. Also known as a PC Belt (Pyramid’s Brand), quick fix, zero down time, temp belt or band as well as under other names.
Ultimate elongation	Percentage an elastomeric product will stretch before rupturing (breaking).
Ultimate tensile strength	Force required to rupture (break) an object by stretching, reported in PSI.
Unreinforced belt	Elastic belt with no fiber reinforcement embodied within the body.
Unsupported belt	Elastic belt with no fiber reinforcement embodied within the body.
Urethane	Another term used for polyurethane.
Zero down time	Usually refers to a repair belt which is used to temporarily replace failed live roller conveyor belts. Also known as a PC Belt (Pyramid’s Brand), quick fix, twisted belt or band, temp belt or band as well as under other names.