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Glossary of technical terms
| Term | Explanation |
|---|---|
| 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. |