Abrasion |
Wearing away by rubbing, scraping. |
Adhesion |
The bonding strength between two materials. |
Ageing |
The exposure to an environment for a period of time. |
Arc of contact |
The circumferential portion of a pulley which is engaged by a belt. |
Belt clamp |
Beams or metal plates secured transversely on both sides of belt end(s) to hold ends in a desired position. |
Belt cleaning device |
A scraper or rotating or washing device pressed against the belt surface to remove material stuck to the belt. |
Belt fastener |
A device for holding two ends of a conveyor belt together. |
Belt modulus |
The force per unit width of belt required to produce a stated percentage of elongation. |
Belt sag |
The amount of vertical deflection of a conveyor belt from a straight line between idlers, usually expressed as a percentage of the center to center spacing of the idlers. |
Belt slip |
The speed differential between the belt and the pulley surface. |
Belt training idler |
An idler having a belt-actuated swivel mechanism to automatically control side drifting of a conveyor belt. |
Belt turnover |
A system of idlers to turn a belt over. |
Bending modulus |
The force required to induce bending around a specified radius and, hence, a measure of stiffness. |
Bend pulley |
A pulley used to change the direction of a belt. |
Bias cut |
A cut of a textile material or belt ends made diagonally at an angle less than 90 degrees - usually 30° - to the longitudinal axis. |
Binder warp yarn |
One of the warp systems in a straight warp fabric interlaced with the filling yarn to provide the strength to hold mechanical fasteners. |
Bleeding |
Migration to the surface of plasticizer, waxes or similar materials to form a film or beads. See also Bloom. |
Blister |
A raised spot on the surface or a separation between layers usually forming a void or air-filled space in the vulcanized conveyor belt. |
Booster drive |
Used in some long conveyors to reduce the power/tension at the drive pulley. |
Bottom cover |
The non-carrying belt side towards the pulleys. |
Breaker |
An extra ply for shock absorption to minimize gouging. |
Bucket elevator belt |
A transversely rigid belt with buckets attached, for vertical conveying. |
Calender |
A machine equipped with three or more heavy drums revolving in opposite directions. |
Capacity |
The material load on the belt, given in tons per hour (t/h). |
Carcass |
The fabric, cord and/or metal reinforcing section of a belt, as distinguished from the rubber cover. |
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. |
Center-to-center |
The distance between the center of two pulleys or idlers. Sometimes also called centers or center distance or conveyor length. |
Cleaner |
A device for removing adherent material from the belt |
Cleat |
Transverse raised sections on a conveyor belt to stabilize material carried up an incline. |
Cord fabric |
The fabric elongation is adjusted by means of the weft yarn twist. |
Compression set |
The deformation in a material remaining after it has been subjected to and released from a compressive force. |
Counter weight |
The weight applied to the take-up assembly to maintain proper belt tension. |
Cover |
The outer rubber (or PVC) components of a belt. |
Cracking |
A sharp break or fissure in the surface. See also "Wrinkle". |
Creep |
The action of a belt alternately losing speed on the driving pulley and gaining speed on the driven pulley. |
Crimp |
The waviness of the yarn in a woven fabric or 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. |
Crowned pulley |
A pulley with a greater diameter at the center, or other points, than at the edges. |
Cut edge |
The uncovered edge of a belt, created by cutting after vulcanization. |
Degradation |
A deleterious change in the chemical structure of a material. |
Delamination |
The separation of layers of material. |
Denier |
A yarn sizing system for continuous filament synthetic fibers on the basis of the weight in grams of 9000 meters of the yarn. |
Density |
The ratio of the mass of a body to its volume or the mass per unit volume of the substance. For ordinary practical purposes, density and specific gravity may be regarded as equivalent. |
Dipped fabric |
Coated with rubber compound by passing through a rubber solution and drying. |
Dutchman |
A short section of belting mechanically spliced into a length of belting and removed when the take-up allowance is exceeded. |
Dynamometer |
An apparatus capable of inducing various loads for evaluation of dynamic belting properties. |
Electrical conductivity |
A measure of how well a material accommodates the transport of electric charge, measured in Ohm (Ω). |
Endless length |
The length of a closed belt (without splice allowances). |
EOB |
Energy optimized belt |
Extrusion |
A process whereby rubber is forced through a shaping orifice. |
Eytelwein's equation |
Determines the optimum difference between the forces F1 and F2 without belt slip. |
Fatigue |
The weakening of a material occurring when repeated application of stress causes permanent strain. |
Feeder belt |
A belt that discharges material onto another conveyor belt. |
Filament |
A continuous fiber of very high length. |
Fire resistance |
Retards the burning action of fire or flame. Achieved by adding fire retardents to the compound. |
Friction |
The resistance to motion due to the contact of surfaces |
Gauge |
The thickness of a belt or its individual elements. |
Gouging |
The effect of sharp heavy material falling onto a conveyor belt cover to loosen or tear out pieces of the cover. |
Gravity take-up |
A mechanical system that adjusts for the stretch or shrinking of a conveyor belt automatically by a weighted pulley in the system. |
Hardness |
Degree of resistance to indentation |
Head pulley |
The pulley at the discharge end of the conveyor |
Hooke's Law |
Hooke's law of elasticity states that if a force (F) is applied to an elastic spring, its extension is linearly proportional to its tensile stress σ and modulus of elasticity (E): ΔL = 1/E × F × L/A = 1/E × L × σ |
Hysteresis loss |
A loss of mechanical energy due to successive deformation and relaxation, measured by the area between the deformation and relaxation stress-strain curves. |
Idler |
A nonpowered roller supporting the belt |
Impact |
A stroke of a body dropping on the belt |
Impact idler |
A belt idler having a resilient roll covering, resilient molded elastomer rings, springs or other means of absorbing impact energy at the place where material falls onto the belt. |
Impact resistance |
The relative ability of a conveyor belt assembly to absorb impact loading without damage to the belt. See also "transverse reinforcement". |
Joint |
The connection of two belt ends |
Kevlar |
A trademark for aramid |
Lagging |
A smooth or embossed covering on a pulley to increase friction between belt and pulley. |
LRR |
Low rolling resistance |
Maximum tension |
The highest tension occurring in any portion of the belt under operating conditions |
Mechanical fastener |
Any mechanical device used to join the ends of belting. |
Modulus of elasticity |
The force divided by the percent elongation to cause the elongation. |
Molded edge |
A solid rubber belt edge formed in a mold. |
Nylon |
A trademark for polyamide. |
Ozone cracking |
Cracks caused by exposure to an atmosphere containing ozone. |
Overend discharge |
A discharge over the head of the conveyor |
Payne effect |
Is observed under cyclic loading conditions with small strain amplitudes, and is manifest as a dependence of the viscoelastic storage modulus on the amplitude of the applied strain. |
Permanent elongation |
Elongation permanently removed from belting when it is first used |
Permeability |
Usually the quality or condition of allowing passage of air through a steel cord to identify the degree of rubberization. |
Plastisol |
A suspension of a finely divided polymer (PVC) in a plasticizer. |
Ply |
A layer of fabric in a belt. |
Rating |
The minimum belt breaking strength (DIN) of a belt in Newtons per millimeter of belt width.
In the USA sometimes used as a term for the working tension. |
Regenerative conveyor |
A conveyor for which the head is at a substantially lower altitude than the tail (downhill conveying), generating power. |
Return idler |
Part of a conveyor's return run. |
Safety factor |
A multiplier applied to the calculated maximum force to which a conveyor belt splice (as the weakest link in a conveyor belt) will be subjected. A factor of safety accounts for imperfections in materials, flaws in assembly, material degradation, and uncertainty in load estimates.
Note: In the USA usually the safety factor is related to the belt but not to the splice. |
Screw take-up |
A take-up for a conveyor system in which movement of a pulley-bearing block is accomplished by means of a screw. |
Self-extinguishing |
If set under fire the belt will generate gases that extinguish the fire. |
Shelf storage life |
The period of time prior to use during which a product retains its intended performance capability. Important for (uncured) splicing material. |
Shuttle conveyor |
A belt conveyor having overend discharge, the whole being mounted on a travelling carriage capable of being shuttled backwards and forwards. |
Skim coat |
A layer of rubber material laid on a fabric but not forced into the weave. Normally laid on a frictioned fabric. |
Skirt board |
In a conveyor system, the vertical or inclined plates located longitudinally and closely above the belt to confine the conveyed material. |
Skiver |
Grinding equipment to bevel belt ends for an overlap splice. There are sanding belt, drum and disk skivers in use. |
Slab belting |
Belting made in wide widths and long lengths for later slitting into narrower widths and cutting into shorter lengths. |
Slope belt |
A conveyor belt used to carry material along an inclined flight. |
Snub pulley |
A non-driven pulley located close to the drive pulley to provide a greater arc of contact around the drive pulley. |
Solid woven |
A single ply ("monoply") interwoven fabric. |
Splice allowance |
Additional length required to make a splice. |
Splicer |
A field splicing engineer. |
Straight warp |
Made of high tenacy polyester fibres for the warp and weft polyamide yarns, both held together by a polyamide composite yarn. |
Tail pulley |
The pulley near the loading end of the conveyor system |
Take-up pulley |
A pulley which can move in space in order to maintain relatively constant tension. |
Tensile member |
The fabric, cord and/or metal reinforcing section of a belt, as distinguished from the rubber cover. |
Tension |
Stress on the belt tending to cause extension. |
Tie gum |
A thin sheet of unvulcanized rubber inserted between plies in vulcanized repairs of splices. |
Training idler |
An idler mounted on a mechanical device, actuated by the belt moving against it to make the belt run straight. |
Transition distance |
The distance between the last fully troughed idler and the flat driving or discharge pulley. |
Transverse reinforcement |
An additional layer of single polyamide cords in custom-made pitch and diameter for increased rip and impact resistance. |
Tripper |
A device for discharging material from a belt. |
Troughability |
The property of a belt that permits it to conform to the contour of troughing idlers. |
Viscoelasticity |
The property of materials that exhibit both viscous and elastic characteristics when being deformed. Viscoelasticity is the result of the diffusion of atoms or molecules inside of an amorphous material. |
Viscosity |
The resistance of a material to flow under stress. |
Vulcanization |
An irreversible process during which a rubber compound, through a change in its chemical structure, becomes elastic. See more. |
Vulcanizer |
A mobile curing machine for field splicing (also called press). |
Warp |
The lengthwise yarns in a woven fabric. |
Weft |
The crosswise yarns in a woven fabric. |
Wrinkle |
An appearance usually resulting from curing with separation paper or cloth. |
Young's modulus |
The stress per unit strain for elastic materials. |