Portec Glossary of Terms

Conveyor Glossary of Terms

AC inverter: an electronic device that controls the speed of an AC motor by varying the frequency of the input electrical power.

Acceptance: acknowledgment by the purchaser (or user) that equipment or services provided are suitable for accommodating the intended function.

Accessibility: the ease of access or approach to equipment for operation, inspection, maintenance and lubrication.

Accumulation conveyor: any conveyor designed to permit accumulation of packages, objects, or carriers.

Adjoining conveyor: the next conveyor in the conveyor stream on the infeed or takeaway sides.

Adjustable speed drive: a drive or power transmission mechanism that incorporates a device that permits control of its speed within design limits.

Air bar: a hollow bar on the angled end of a belt merge conveyor that is used as a substitute for an end roll. Pressurized air escapes through small holes along the length of the bar to support a conveyor belt on a cushion of air.

Alignment: the position of parts, or components, in relation to each other.

Alligator lacing: lacing attached to the belt edge for the purposes of joining the ends of the belt together to form a continuous loop.

Anchor bolts: bolts used for fastening the conveyor to the floor, pit, or other foundation, or to ceiling or overhead structure when the conveyor is suspended.

Angle bar: the bar on the angled end of an angle belt merge conveyor that supports the conveyor belt as it wraps around the end of the conveyor.

Angle of inclination: the angle a conveyor is inclined from the horizontal.

Anti-runway: a safety device to prevent uncontrolled movement of a loaded incline or decline conveyor or carriers in the event of mechanical or electrical failure.

Anti-static: a measure of surface electrical conductivity of a conveyor belt material where its resistivity is in the >109 -<=1014 ohm range.

Approval: the concurrence or acceptance which ratifies or confirms an existing understanding as to the terms, construction, methods of operation, or other terms.

Arc of contact: the angular wrap in degrees of a belt around a pulley. Attachment link -a fastener that connects the edge of a conveyor belt to a roller chain. see Chain attachment.

Automatic lubricator: a device used to lubricate the chain, trolley wheels, or other conveyor components automatically.

Automatic take-up: a take-up having provisions which permit it to automatically compensate for stretch, shrink or wear of belts, cables, chains, etc., and to maintain proper tensions. See Take-up.

Axle: a shaft, either rotating or non-rotating on which are mounted driving or supporting wheels or rollers.

Bare back belt: a belt in which one textile face is free of any coating.

Bare pulley: a pulley which does not have the surface of its face covered (or lagged).

Bearing life: manufacturers rated life of bearing based on load and speed factors. Life is limited by fatigue and can be measured in number of revolutions or hours of operation at a specified speed of rotation.

Bed: that part of a conveyor upon which the load or carrying medium rests or slides while being conveyed.

Bed idler roll: a roller that is inset into a conveyor slider bed to reduce the sliding friction of the conveyor belt.

Bed roll: see Bed idler roll

Bed relief roll: see Bed idler roll

Belt assembly: a conveyor belt that is fabricated for a specific conveyor along with all associated components required for installation or operation.

Belt carcass: the tension carrying portion of the conveyor belt. May be comprised of single or multiple plies of fabric, cord, or steel cable bonded together with rubber or other material.

Belt cleaner: a device to clean or remove material which clings to a conveyor belt.

Belt cleat: an attachment fastened to the conveyor belt to act as a pusher, support, check or trip, etc., to help propel material, parts, or packages along the normal path of conveyor travel. May be of various sizes and shapes to suit the application.

Belt conveyor: an endless fabric, rubber, plastic, leather, or metal belt operating over suitable drive, tail end and bend terminals and over belt idlers or slider bed for handling bulk materials, packages, or objects placed directly upon the belt.

Belt conveyor idler: a roller or series of rollers which support the belt of a conveyor.

Belt cover: the material applied to the top and/or bottom surfaces of the carcass of a belt for abrasion resistance, to modify frictional characteristics and/or protection of the carcass.

Belt drive chain: a roller chain, that is attached to the edge of a conveyor belt, that transmits the driving force to the conveyor belt.

Belt fastener: a device for holding the ends of a belt together.

Belt grade: a classification of the quality and properties of the rubber or plastic components of belting.

Belt idler: see Idler, belt conveyor.

Belt misalignment: the lateral movement of a conveyor belt to either side of its intended path.

Belt modulus: the force per unit width of belt required to produce a stated percentage of elongation.

Belt ply: a layer of duck or cords used in constructing the carcass of a conveyor belt.

Belt power curve: a curved belt conveyor that is used to change the direction of a conveying path without changing the orientation of the product within the material flow.

Belt scraper: a blade or blades caused to bear against the moving conveyor belt for the purpose of removing material sticking to the conveyor belt.

Belt slip: the action of a belt which takes place when the pull exceeds the friction grip on the pulley, imposing a speed differential between the pulley surface and the belt.

Belt speed: the length of belt, chain, cable, or other linkage which passes a fixed point within a given time. It is usually expressed in terms of "feet per minute", "meters per minute" or "meters per second".

Belt training: to properly align an operating conveyor belt.

Belt training idler: an idler having a belt actuated swivel mechanism to control the side runout of a conveyor belt.

Belt width: the width of a conveyor belt that is exposed. This does not include any belt that may be under a shroud or cover.

Belt width centerline: the conveying path centerline as measured in the middle of the exposed belt width.

Belt wiper: a blade or blades caused to bear against the moving conveyor belt for the purpose of removing material sticking to the conveyor belt.

Bend pulley: any pulley used to change the direction of the travel of the belt. Between frame width (BF) —the distance between the conveyor frame rails on a straight belt or roller conveyor.

Between sideguard width: the distance between the sideguards of a conveyor that represents the actual width of the conveying flow. Also see Between frame width (BF).

Bobbing: the slight bumping motion made by a product as it moves across a transfer point between two conveyors.

Bottom cover: the protective cover of a conveyor belt on the surface contacting the carrying idlers.

Brake: a device for slowing down conveyor components; for bringing conveyor equipment to a controlled stop; for holding traveling or traversing equipment in a selected location; for preventing reverse travel; or for controlling overspeed due to the action of gravity.

Brake belt: a stop-feeder device for indexing, spacing, or controlling unit loads.

Build-up: that material which clings to the conveying medium or its parts.

Bushing: (1) in machinery, a removable liner fixed in a bore to improve the bearing surface; (2) in chain, a renewable liner fixed in the barrel of a link, or center link, to provide an improved bearing surface; (3) in chain, a hollow cylinder used to space the sidebars and provide a bearing surface for the chain pin, and on which the rollers may or may not be mounted.

Butt coupling: angles or plates designed to join conveyor sections together.

Capacity: the number of pieces of a defined size, volume of material, or weight of material, that can be handled by a conveyor in a unit of time.

Carcass: see Belt carcass.

Carrying belt: that portion of the belt which carries the load between the loading and discharge points.

Carrying idler: (1) in belt conveyors, the belt idlers upon which the load-carrying portion of the belt is supported; (2) in live roller conveyors, the rollers upon which the load is supported while being conveyed.

Casters: wheels mounted in a fork used to support and make conveyors portable. Can be either rigid or swivel.

Ceiling hanger: a support fastened from an overhead frame work to position and carry loads.

Center drive: a drive which transmits motion to a conveyor at a point other than the terminals.

Centerline diameter: in curved conveyors, twice the distance from the center of the arc to the centerline radius of the conveyor.

Centers: the distance measured along the carrying run of a conveyor from the center of one terminal wheel or pulley to the center of the opposite terminal wheel or pulley; also, horizontal centers or vertical centers, the distance from the center of one terminal or bend wheel to the center of another one as projected on the horizontal or vertical plane.

Central lubrication: a system to dispense lubricant to a group of bearings from a single location.

C-face/shaft mount: a motor and gear reducer drive arrangement where the motor is fastened directly to the gear reducer using a "C" type mounting flange and the gear reducer is mounted to the drive shaft of the conveyor by means of a hollow output shaft.

Chain: a series of links pivotally joined together to form a medium for conveying or transmitting motion or power.

Chain alignment: the positioning of a chain sprocket so that the chain path is centered on the sprocket.

Chain attachment: that adjunct of a chain that is used to connect it to the load-carrying medium or that which is propelled.

Chain barrel: that portion of a chain link that joins and is between the side bars at the pivot point, the inside of which forms the live bearing seat for the pin and the outside of which provides the contact surface for or with a sprocket or wheel.

Chain cover: a shroud used to cover a chain.

Chain deflection: the amount of looseness in a chain.

Chain drive: a power transmission device employing a drive chain and sprockets.

Chain elongation: as a chain is subjected to increasing stress or load, it becomes longer.

Chain guard: a covering or barricade for drive or conveyor chains for safety purposes.

Chain guides: members paralleling a chain that confine the movement of the chain within a defined path.

Chain guide support: a device that maintains the position of a chain guide.

Chain joint: the parts that form the pivoting portion of the chain (pins, bushings, barrels, and rollers). Chain link: a chain unit of one pitch length.

Chain pin: the pin that is used to connect links of a chain and upon which, or about which, the links pivot.

Chain pitch: the distance between the centers of two successive chain pins.

Chain path a defined line of movement of a chain

Chain path radius: in curved conveyors, the distance from the centerpoint of a curve to the mid-point of the chain along its line of movement.

Chain pull, effective: see Horsepower pull.

Chain tension: the pulling force of a chain under load.

Chain wear guides: members paralleling a chain that confine the movement of the chain within a defined path.

Chute: a trough through which bulk materials or objects are directed and lowered by gravity. The trough may be opened or enclosed, straight or curved.

Cleat: an attachment fastened to the conveying medium to act as a pusher, support, check or trip, etc., to help propel material, parts, or packages along the normal path of conveyor travel. May be of various sizes and shapes to suit the application.

Cleated belt: a belt having raised sections spaced uniformly to stabilize flow of material on belts operating on inclines. Cleats may be a part of the belt or fastened on.

Clipper lacing: lacing attached to the belt seam with a clipper lacing maching

Clutch-brake drive: a drive used to disengage motor from gear reducer and stop conveyor immediately without stopping the motor or cutting the power.

Clutch drive: a drive used to disengage motor from gear reducer without stopping the motor or cutting the power.

Coefficient of friction: a numerical expression of the ratio between the force of contact existing between two surfaces and the resistant force tending to oppose the motion of one with respect to the other. The coefficient of friction is used in determining the power necessary to drive a machine; to determine the slope angles used in hoppers, bins, chutes. and bunkers; or to determine the maximum angle of inclination for a conveyor.

Connecting link: a special chain link that is used to connect two ends of a chain.

Connecting link clip: a special clip that holds the connecting link plate in position.

Constant speed drive: a drive with no provision for variable speed or a drive with the characteristics necessary to maintain a constant speed.

Contamination: the presence of foreign or undesirable substance(s) in a material. Contaminants can be of many varieties: Moisture in a material, particle sizes, weight, tramp iron, and other foreign or dissimilar materials.

Converging: a section of conveyor where two or more conveyors meet and merge into one conveyor.

Conveying width: the width of the path in the conveying line where product actually flow. This is the same as the Between Frame (BF) width or Between sideguard width.

Conveyor: a horizontal, inclined or vertical device for moving or transporting bulk materials, packages or objects in a path predetermined by the design of the device and having points of loading and discharge fixed. or selective; included are skip hoists and vertical reciprocating and inclined reciprocating conveyors. Typical exceptions are those devices known as industrial trucks, tractors and trailers, tiering machines (truck type), cranes, hoists, monorail cranes, power and hand shovels, power scoops, bucket drag lines, platform elevators or conveyors designed to carry passengers or the elevator operator. and highway or rail vehicles.

Conveyor belt: a belt used to carry materials and transmit the power required to move the load being conveyed.

Conveyor belt pitch line: a horizontal plane located centrally in the carcass at which, for computation purposes, all belt tension is theoretically carried.

Conveyor belt stretch: the temporary change in length of a belt. Stretch varies directly with tension in the belt. Stretch is usually measured as a percentage of length and is a function of the working load, environmental and ambient conditions.

Conveyor chain: a chain used in the conveying medium of conveyors.

Conveyor frame: the structure which supports the machinery components of a conveyor.

Conveyor speed: the length of belt which passes a fixed point within a given time. It is usually expressed in terms of "feet per minute", "meters per minute" or "meters per second"..

Conveyor width: (1) in unit handling, the dimension inside to inside of frame rails; (2) in belt conveyors for bulk materials, the width of the belt; (3) in vibrating conveyors, distance between side walls; (4) in slat conveyors, the length of the slat.

Conveyor width, effective: (chain driven live roller)the dimension between side rail and chain cover plate.

Corner conveyor: a belt conveyor which is produced with a degree of bend so as to convey products away from the straight flow. see Curved belt conveyor.

Coupler link: a link designed for more readily connecting sections of chains.

Cover gauge: the thickness of the belt cover over the carcass of the conveyor belt.

Crossmembers: structural members which maintain frame rail spacing on unit handling conveyors.

Crown: (Pulley) crown is the rate of taper of a pulley face and is defined as the amount (expressed in inches per foot of total face width) by which the diameter at the center of the face exceeds the diameter at the edge. The amount of crown may be from 1/16 to 1/8 inches per foot of total face width.

Crown face pulley: a pulley with greater diameter at the center than at the ends.

Cup point set screw: a type of allen set screw used to hold a key in place.

Curve conveyor: any belt, roller or skatewheel conveyor which is produced with a degree of bend so as to convey products away from the straight flow.

Curved belt assembly: a conveyor belt for a curved belt conveyor with all associated hardware.

Curved belt conveyor: a belt conveyor which is produced with a degree of bend so as to convey products away from the straight flow.

Curved belt segments: pieces of curved conveyor belt that are connected together to make a curved conveyor belt. If a curved conveyor belt is damaged by a product jam, it may be repaired by replacing only the effected belt segments.

Cycling: the process of starting and stopping a conveyor in order to control product flow.

Dead load: the combined weight of the conveyor elements and supports. See also Live load.

Declining conveyor: a conveyor transporting down a slope.

Deflector: a device across the path of a conveyor placed at the correct angle to deflect objects. See also Diverter.

Deflector wheel: a wheel on the side of a product flow path used to reposition the product.

Degree of incline: angle of slope of a conveying surface.

Direction of belt: travel the direction of travel of the product on the conveyor

Discharge chute: a chute used to receive and direct materials or objects from a conveyor.

Discharge end: the end of a conveyor or feeder most downstream usually where the material is fed off the unit.

Diverging section: a section of roller, wheel, or belt conveyor which makes a connection for diverting articles from a main line to one or more branches.

Diverter: a mechanism used to alter the path of a unit load for traffic control or sortation purposes. See also Deflector.

Double helix: two spiral conveyor lines attached on opposite sides of a common center support structure.

Drive: an assembly of the necessary structural, mechanical and electrical parts which provide the motive power for a conveyor.

Drive belt: a belt which is used to transmit power or motion from one part to another.

Drive chain: a chain used to transmit power.

Drive end: the end of the conveyor where the drive unit is located.

Drive pulley: a pulley mounted on the drive shaft that transmits power to the belt with which it is in contact.

Drive shaft: (1) a main driving shaft on which conveyor sprockets, gears. or pulleys are mounted. This shaft is connected to the drive unit through a coupling, sprocket, gear, or other form of mechanical power transmission; (2) a shaft used to support the end of a conveyor screw in a trough end and as a driving connection between a conveyor screw and the power transmitting medium.

Driven roller: any carrying roller driven by belting, chain or other propelling medium.

Drive shaft extension: the end of a drive shaft that extends outside the supporting bearing and is used to transmit power from the drive unit to the drive pulley.

Drop: (l) the distance from the top of a bearing hangar to the center of the shaft of a screw conveyor, (2) in a trolley conveyor the vertical distance from the top of the power track to centerline of the chain, (3) in a trolley conveyor the distance which describes the amount of change in elevation of a compound curve, (4) the vertical distance from the bottom of power track to the bottom of the free track in a power and free track section, (5) see Pitch.

Drop hanger: a support fastened from an overhead frame work to position and carry loads. see Ceiling hanger.

Dual drive: (1) any conveyor drive employing two prime movers; (2) a single prime mover powering two conveyors.

Duck: a term used in describing belting applied to a wide range of medium and heavyweight woven fabrics made from cotton or synthetic fibers or a combination of both. Duck is also identified as canvas, army duck, belt duck, harvester duck, hose duck and shoe duck.

Durometer: a measure of the hardness of rubber or plastic materials.

Dutchman: a short section of belt, provided with a mechanical splice, in a conveyor belt which can be removed when take-up provision has been exceeded.

Dynamic load: the reversing forces transmitted to the supporting structure by the vibrating equipment when operating. Peak dynamic loads may occur at other than the running frequency.

Eccentric shaft: a shaft upon which an eccentric is integral or mounted.

Eccentric locking collar: a bearing collar that uses an eccentric as a means of fixing it to a shaft.

Effective chain pull: see Horsepower pull. Not to be confused with chain tension.

Electric braking: a form of retardation accomplished by electrical means. Typical examples are: (1) regenerative braking: a form of braking resulting when an induction motor is driven beyond its synchronous speed and consequently acts as a generator. In this condition, it will exert braking torque; (2) dynamic braking;(a) in a DC motor a form of braking resulting from the motor acting as a generator loading itself through a resistance loop; (b) in AC motors this type of braking is accomplished by disconnecting the power supply and applying DC excitation to one phase; (3) eddy current braking: a form of electric coupling used as a brake through excitation of its coil.

Elevating conveyor: any conveyor used to discharge material at a point higher than that at which it was received. The term is specifically applied to certain underground mine conveyors.

Elevation differential: in elevating and declining conveyors, it is the distance between the entry elevation and the exit elevation.

Elongation: a permanent change in length of a conveying medium such as belt, chain, or cable. Elongation usually results from one or more conditions; for example, wear, readjustment of members comprising construction, exceeding elastic limit, change in form from force applied, etc. See Stretch.

Emergency stop: a stop arising from a sudden and unexpected need, and not as a part of the normal operation.

Emergency stop device: a device which must be actuated to stop a conveyor in an emergency situation.

Enclosure: a guard, shield or housing to effect a certain degree of isolation for a component, a piece of equipment or material.

End roll: a pulley at the terminal ends of a belt conveyor.

End roll: assembly an end roll and end roll shaft.

End roll diameter: the diameter of an end pulley. On curved belt conveyors with tapered end rolls, the diameter of the end pulley varies across its face.

End roll sprocket: on chain/belt conveyors, it is the sprocket on the end roll shafts adjacent to the end roll.

Engineering change: any alteration or revision made to engineering drawings or specifications.

Explosion-proof: equipment designed in accordance with existing codes and standards such that it will operate in a specified hazardous environment without causing an explosion.

Exposed belt width: the actual width of the belt within the conveying path. Normally, the exposed belt width is narrower than the conveying width.

Extendable conveyor: a conveyor which may be lengthened or shortened while in operation to suit operating needs.

Face: the outer surface of a pulley in contact with a belt; the outer surface of a gear, roller, or drum usually expressed in terms of inches of width.

Factor of safety: ratio of the ultimate strength as related to the rated working load of a given material or apparatus.

Factory sealed: closed or sealed at place of manufacture.

Fall: see Pitch.

Feed conveyor: an adjacent conveyor within a conveyor flow that brings the product to the conveyor entry.

Feed end: the end of a conveyor or feeder most upstream usually where the material is fed onto the unit.

Feeder: a conveyor or other mechanism adapted to control the rate of delivery of bulk material, packages, or objects, or a device that controls, separates, or assembles objects

Field adjustment: necessary work done as a part of normal equipment erection to provide proper assembly or operation of the equipment.

Field fitting: work done as part of normal equipment erection which requires the assembly of parts which were fabricated to generally acceptable shop tolerances.

Field rework: work done which is not part of normal equipment erection but is necessary for the proper operation of the equipment and/or to meet contract specifications.

Filler plates: see Fill-in plates.

Fill-in plates: closely fitted plates positioned between the rollers of non-powered or powered roller conveyors. See also Guard.

Finger splice: a type of belt splice that utilizes die cut fingers on the end of each belt segment to increase the strength of the splice by increasing the length of the glued edge.

Flanged bearing: a bearing having a housing with a mounting surface in a plane normal to the axis of the shaft.

Flat belt conveyor: a type of belt conveyor in which the carrying run of the conveyor belt is supported by flat belt idlers or by a slider bed.

Flexible coupling: a mechanical connector to transmit torque without slip and to accommodate misalignment between axially oriented driven machine members.

Floor supports: supporting members with vertical adjustments for leveling the conveyor.

Flow: the direction of travel of the product on the conveyor.

Foot end: see Tail end.

Frame: the structure which supports the machinery components of a conveyor.

Frame rails: members which support the conveying components of non-powered or powered conveyors. Friction, coefficient of: see Coefficient of friction.

Functionality: the essentail intended purpose for which the machine was designed.

Gearmotor: a motor and speed reducer combination where the two units are flanged for connection to each other and have one output shaft; or where the two units are closely coupled with the motor resting on a base which is an integral part of the speed reducer housing.

Gravity conveyor: see Roller conveyor, Wheel conveyor.

Gravity feeder: conveyor bed of closely spaced wheels or rollers used to transfer unit loads from gravity flow to incline belt conveyor or from decline belt conveyor to gravity flow.

Gravity hopper: a surge bin attached to the tail end of a portable conveyor which utilizes the conveyor belt as a live bottom.

Guard: (1) a covering or barricade for safety purposes such as gear, chain and nip guards; (2) a structure mounted below an overhead conveyor to protect personnel.

Guard rails: see Guide.

Guide: (1) members paralleling the path of a conveyor and limiting the conveyor or its parts to movement in a defined path; (2) members paralleling the path of a conveyor and limiting the product on the conveyor to movement in a defined path.

Guide rails: see Guide. Half-dog point set screw—a type of allen set screw that is used to hold a bearing, collar or sprocket on to a shaft.

Head end: usually the ultimate delivery end of a conveyor.

Head frame: the structure that supports the terminal machinery at the head end of a conveyor or elevator. See Frame.

Head pulley: a pulley mounted on the head shaft of a conveyor.

Headroom: the vertical distance needed to make possible a workable arrangement of some specified piece of equipment or portion thereof.

Head section: the head end of a conveyor or elevator consisting of the head frame and terminal machinery.

Head shaft: the conveyor terminal shaft at the head end of a conveyor. Not always the drive shaft.

Hinged section: a section of conveyor equipped with a hinge mechanism for movable service.

Hopper: a container having a funnel-shaped bottom, or a bottom reduced in size, narrowed, or necked to receive material and direct it to a conveyor, feeder, or chute.

Horizontal curve: a conveyor section used to change the direction of travel.

Horsepower: a measure of the time rate of doing work defined as the equivalent of raising 33,000 pounds one foot in one minute. Electrically, one horsepower is 746 watts.

Horsepower pull: the effort necessary to maintain normal operating speed of a conveyor under a rated capacity load. To this must be added the effort of acceleration, drive losses, etc., to arrive at a final driving effort. Horsepower pull may be referred to in terms such as effective tension, chain pull, turning effort, gear tooth pressure, etc.

Idler: a pulley, sheave, sprocket, or wheel around which a belt, cable, or chain passes in changing direction of travel. See Snub pulley; Bend pulley. See also Idler, belt conveyor.

Idler, belt conveyor: a roller or series of rollers which support the belt of a conveyor.

Idler pulley: see Idler; Pulley; Snub pulley.

Idler roller: any carrying roller of alive roller conveyor not driven. Also the rollers of a belt idler. Idler shaft: a shaft which supports an idler wheel, pulley, etc,

Inching: see Jogging.

Indexing: the controlled operation of equipment to obtain predetermined intermittent movements.

Induct: a conveyor or conveyor subsystem including required controls which properly gaps, identifies, and tracks for transferring a wide range of unit loads as required by the sort subsystem.

In-feed end: the end of the conveyor nearest the loading point.

Inside radius: on curved and spiral conveyors, it is the side of the conveyor closest to the vertex of the curve.

Inside radius bearing: on curved and spiral conveyors, the end roll bearings on the inside radius side of the conveyor.

Inspection: the process of comparing a system and/or its component units with accepted contract specifications.

Insulative: a measurement of the electrical conductivity of a belt material where the resistivity is greater than 1014 ohms.

Intermediate drive: a drive which transmits motion to a conveyor at a point other than the terminals.

Jackscrew: a horizontally or vertically mounted screw used for the purpose of adjusting and maintaining adjustments for alignment of a machine part.

Jogging: the manual operation of equipment to obtain small movements of the driven machine.

Knee brace: a structural brace at an angular position to another structural component for the purpose of providing support and/or stability of the conveyor frame.

Knife-edge conveyor: a belt conveyor with a very small diameter of end roll.

Laced seam: a means of attaching belt segments together that uses hinged metal fasteners that are mechanically secured to the belt ends.

Lacing: a mechancial means of fastening belt segments together. Common types of belt lacing include Alligator, Clipper, Flexco and Minet.

Lagging: a smooth or embossed covering or coating applied to a pulley to reduce belt slippage, wear, and prevent material build-up.

Lagged pulley: a pulley having the surface of its face covered with lagging.

Lap splice: a type of belt splice where the ends of the belt segment overlap each other. The belt ends must be skived so the finished thickness of the splice is the same thickness as the belt.

Left hand: in straight conveyors, the left hand is determined by facing in the direction in which the material is flowing. In curved and spiral conveyors, one stands in the vertex of the curve and faces the inside radius frame. When the material flows from the right to the left (counter-clockwise), it is a left hand conveyor. In a left hand merge conveyor, the material flows left as it leaves the angled end of the conveyor. In a left hand diverge conveyor, the material enters the conveyor from the left.

Left inside: on curved and spiral conveyors, it is the side of the conveyor that is closest to the vertex of the curve and on the left side when viewing the conveyor from the vertex.

Left outside: on curved and spiral conveyors, it is the side of the conveyor that is farthest from the vertex of the curve and on the left side when viewing the conveyor from the vertex.

Leg angle: the angle between the centerline of the supporting legs and a line normal to the deck surface or base.

Life of the equipment: the time period that the piece of equipment will operate in performing the specified function with normal maintenance.

Lift: the net vertical distance through which material is moved against gravity by a conveyor.

Limit switch: a mechanical device which, when activated, opens or closes contacts to alter the control circuit.

Linear load at centerline: on curved and spiral conveyors, a measurement of conveyor loading that divides the total load on the conveyor by the centerline length.

Live load: the weight of material being moved. See also Dead load.

Live storage: storage on a suitably designed power-operated conveyor, power-and-free conveyor, roller conveyor or other combinations upon which accumulated packages or objects can advance as other loads are removed from the discharge end.

Load: (1) unit load is the weight per unit of length, or weight of an individual unit on a conveyor, (not to be confused with capacity); (2) total load is the total weight on the conveyor. See also live load.

Lock-out/tag-out: a procedure of disconnecting power to a machine before performing maintenance and placing tags on the power switches to prevent reconnecting the power before the maintenance is completed.

Loctite: a liquid threadlocker that fills the gaps in screw threads and prevents a screw from loosening from vibration.

Lowering conveyor: any type of vertical conveyor for lowering objects at a controlled speed.

Lubricator, automatic: a device used to automatically lubricate the chain, trolley wheels or other conveyor components.

Magnetic brake: a brake usually mounted on a motor shaft with means to engage automatically when the electric current is cut off or fails.

Maintenance: upkeep of the property or equipment including regular programmed inspection, lubrication, adjustment, and repair or replacement of working parts as required.

Materials handling: the art and science involving movement, packaging, and storage of substances in any form.

Mating butt flange: angles or plates designed to join conveyor sideguard sections together.

Mating conveyor: the next conveyor in the conveyor stream on the infeed or takeaway sides.

Maximum angle of inclination: the maximum angle from the horizontal at which a conveyor may be inclined and still deliver a predetermined quantity of bulk material within a given time. As the maximum angle is approached, the rate of handling of bulk materials is usually decreased. For unit handling conveyor the maximum angle of inclination is that at which the unit load may be conveyed without slippage or tumbling. See Coefficient of friction.

Maximum belt tension: the highest tension occurring in any portion of a belt in a conveyor or elevator system under operating conditions. In conveyors the maximum tension may occur at a point other than at the drive pulley.

Maximum capacity: the greatest capacity rate that can be placed on a conveyor during operation. Maximum or surge capacities are expected to be of a duration of usually 10 seconds or less. If they are for a longer duration, the time increment is to be accurately defined in the request for quotation by user and may become the rated capacity.

Mechanical lacing: See Lacing.

Merge: a conveyor or conveyor subsystem complete with required controls to consolidate material handled from two or more inbound conveyors.

Meter belts: one or more in-line conveyors used to provide controlled material discharge. See also Induct and Brake belt.

Metering conveyor: in package handling, a short powered conveyor whose speed and motion are controlled to release unit loads at a predetermined rate.

Minimum accelerating time: the minimum time allowed to accelerate a conveyor from rest to normal speed without exceeding the permissible starting tension established by the belt manufacturer for the particular belt used.

Minimum arc: on curved and spiral conveyors, the minimum allowable degree of arc of the conveyor. Minimum arc is limited by the space required for bearing housings, the type of belt splice and the diameter of the tapered end rolls on the inside radius.

Minimum belt tension: the lowest tension occurring in a belt in a conveyor or elevator system under operating conditions.

Minimum braking time: the minimum time allowed to decelerate a conveyor belt from normal speed to rest without exceeding the permissible braking tension of the belt or causing festooning of the belt.

Motor enclosures: for specific definitions, refer to NEMA standards "Classification According to Environmental Protection and Methods of Cooling." The following definitions are condensed from this standard. 1. Open Motors (a) Drip Proof (ODP): a housing having ventilating openings so constructed that liquid falling on it at an angle of not more than 15° from the vertical cannot enter the interior. (b) Splash Proof:a housing having ventilating openings so constructed that liquid or solid particles falling on the machine or coming toward it on a straight line or at an angle of 100° from the vertical cannot enter the interior of the housing. (c) Weather Protected: a housing with ventilating passages so constructed as to minimize the entrance of rain, snow, and air borne particles to the electric parts. 2. Totally Enclosed Motors (a) Non-Ventilated (TENV):a completely enclosed housing so arranged to prevent the exchange of air between the inside and outside, but not termed air tight. (b) Fan Cooled (TEFC}: totally enclosed machine equipped for exterior cooling by means of a fan integral with the machine but external to the enclosing parts. (c) Explosion Proof: a housing designed and constructed to withstand an explosion of specified gas or dust which may occur within it and prevent ignition of external gas or dust surrounding the machine.

Motor starter: an electric controller for accelerating a motor from rest to normal speed.

Motor torque: the turning effort expressed in pounds/feet. It is the measure of the ability of a motor to develop power; (1) locked rotor torque (also known as static torque; starting torque) is the minimum torque which a motor will develop at rest for all angular positions of the rotor with rated voltage applied at rated frequency; (2) pull up torque is the minimum external torque developed by a motor during the period of acceleration from rest to the speed at which breakdown torque occurs; (3) breakdown torque is the maximum torque which a motor will develop with rated voltage applied at rated frequency without an abrupt drop in speed; (4) accelerating torque is the net difference at any speed between the torque required by the external load and the torque developed by the motor.

Motorized pulley: a drive unit consisting of a motor, gears, pulley and shaft combination wherein the pulley face (rim) is the rotating member. The shaft is stationary and the gears and motor windings are within the pulley enclosure.

Multi-section frame: a conveyor frame that is disassembled into multiple sections for transport.

Nip point: a point at which a machine element moving in line meets a rotating element in such a manner that it is possible to nip, pinch, squeeze or entrap a person or objects coming into contact with one of the two members. The same definition holds for the similar point with respect to two rotating parts of two converging parts in linear movement.

Nip point guard: a guard placed to eliminate points or areas on the conveyor where injuries might occur.

Noise level: the combined volume and frequency of sound generated by operating equipment whose intensity is measured on the A scale of a standard sound level meter at slow response.

Nominal conveying width: See conveying width

Non-drive shaft: the end roll shaft on a conveyor that is not connected to the drive unit.

Non-powered transfer roll: a non-powered roller that is positioned in the gap between two conveyors in order to aid in products transfering from one conveyor to another.

Non-sparking: the absence of sparking such as may be caused by the striking of one piece of ferrous metal against another or by the discharge of static electricity generated by two or more materials rubbing against one another.

Non-woven belt: a type of conveyor belt material that does not use woven fabric in the carcass

Nose-over: curved or segmented frame sections having rollers properly spaced to provide a transition from incline to level or from level to decline.

Nose roller: a small roller, used on belt conveyors, to reduce the gap at the transfer points. Nylatron —a type of engineered plastic used for making sprockets and conveyor rollers.

Nylock: a nylon insert inside a screw nut that prevents it from loosening from vibration.

Offset coupler link: a coupler link made in the form of an offset link.

Offset link: a link with sidebars offset to provide a center link construction at one end and outside link construction at the other.

Outside conveying radius: on curved and spiral conveyors, it is the distance from the vertex of the curve to the farthest point within the conveying path.

Outside perimeter chain guide: on chain operated curved and spiral belt conveyors, the polymer strips used to guide the belt chain around the outside edge of the conveyor.

Outside radius: on curved and spiral conveyors, the frame side that is farthest from the vertex of the curve.

Outside radius bearing: on curved and spiral conveyors, the end roll bearings on the outside radius side of the conveyor.

Overall length (OAL): the dimension outside the pulley to outside of pulley including belting or lagging, of any conveyor lengthwise.

Overhung load: the weight on a drive shaft extension that can cause the shaft to deflect.

Overload device: a mechanical or electrical device designed to disconnect the driven equipment from the motive power in the event of an overload on the conveyor.

Peak capacity: see Maximum capacity.

Permanent stretch: see Stretch.

Pin: see Chain pin.

Pinch point: a point at which a machine element moving in line meets a rotating element in such a manner that it is possible to nip, pinch, squeeze or entrap a person or objects coming into contact with one of the two members. The same definition holds for the similar point with respect to two rotating parts of two converging parts in linear movement.

Pinch point guard: a guard placed to eliminate points or areas on the conveyor where injuries might occur. Pinch roll drive: a double roll drive which transmits motion to an endless conveyor belt by means of pressure exerted on the belt as it passes between the two rolls.

Pitch: (1) (also Fall) the amount of vertical drop in one turn (360°) of a spiral; the amount of vertical drop in a given unit of length of roller or wheel conveyor; (2) in chain, the distance between the centers of two successive chain pins; (3) the conveyor belt pitch line a horizontal plane located centrally in the carcass at which, for computation purposes, all belt tension is theoretically carried; (4) in sprockets and gears, the distance measured on the pitch circle between centers of adjacent teeth.

Plow: a device positioned across the path of a conveyor at the correct angle to discharge bulk material. See Deflector.

Ply: a layer of duck or cords used in constructing the carcass of a conveyor belt.

Ply tensile: the measurement of the ultimate breaking strength of a belt expressed in either pounds per inch per ply, or pounds per inch of width. Sometimes used in reference to allowable working tension of belts, usually as recommended by the belt manufacturer and expressed as either pounds per inch per ply, or in pounds per inch of width.

Pneumatic take-up: an automatic take-up in which tension is maintained by the use of air cylinders.

Pop-out roller: a special load carrying roller mounted in such a manner as to pop out when foreign objects are introduced between the belt and the roller.

Portable conveyor: any type of transportable conveyor, usually having supports which provide mobility.

Positive drive: a conveyor drive system where all of the compenents are positively connected and does not depend upon friction between component surfaces in order to function.

Power conveyor: any type of conveyor which requires power to move its load.

Power curve: a power driven conveyor for moving unit loads around a horizontal curve.

Powered transfer roll: a powered roller that is positioned in the gap between two conveyors in order to aid in products transfering from one conveyor to another.

Precision roller chain: a type of steel roller chain manufactured to relatively close clearances and tolerances and with highly finished surfaces.

Pressure roller: a roller used for holding the driving belt in contact with the load carrying rollers in a belt driven live roller conveyor.

Preventive maintenance: repairs that are designed to prevent a breakdown of a machine.

Pulley: a cylindrical member, but sometimes polygonal in cross section with provision for mounting on a shaft.

Pulley Face: see Face.

Pulley scraper: a flat blade, the edge of which bears against the face of the pulley to scrape off any foreign material that may be clinging to the pulley face.

Pusher: a powered mechanical device mounted on or adjacent to a conveyor that, when activated will transfer material handled from or to the conveyor. See also Diverter.

Pusher mode: operating a belt conveyor with the drive unit at the feed end of the conveyor.

Queuing conveyor: a belt conveyor that is designed to hold a product and deliver at as required.

Rated capacity: the rated or design capacity of the conveying equipment as stated by vendor. This is the continuous uniform capacity the conveyor can handle.

Receiving hopper: a hopper used to receive and direct material to a conveyor or feeder.

Reducer: see Speed reducer.

Reliability: the ability of equipment to function repeatedly or continuously without unpredictable failure.

Reliability factor: the measurement of the actual number of part failures at predetermined life relative to the total quantity of measured parts as expressed in percentage. Removeable inside radius frame —on curved and spiral belt conveyors, the detachable inside radius frame that allows the replacement of seamless conveyor belts.

Return idler: an idler or roller supporting the return run of the belt. Return roll assembly —a return idler with shaft.

Return roll(er): see Return idler.

Return wheel: a wheel supporting the return run of the belt.

Reversing: (1) under operating design load, the load will move in either direction; (2) for maintenance purposes only, the definition does not imply the ability to run continuously in the opposite direction (sometimes called reverse jog).

Right hand: in straight conveyors, the right hand is determined by facing in the direction in which the material is flowing. In curved and spiral conveyors, one stands in the vertex of the curve and faces the inside radius frame. When the material flows from the left to the right (clockwise), it is a right hand conveyor. In a right hand merge conveyor, the material flows right as it leaves the angled end of the conveyor. In a right hand diverge conveyor, the material enters the conveyor from the right.

Right inside: on curved and spiral conveyors, it is the side of the conveyor that is closest to the vertex of the curve and on the right side when viewing the conveyor from the vertex.

Right outside: on curved and spiral conveyors, it is the side of the conveyor that is farthest from the vertex of the curve and on the right side when viewing the conveyor from the vertex.

Rigid coupling: a mechanical connector between two shafts which transmits torque but does not provide for misalignment.

Riveted chain: a chain in which the ends of the pins are headed and/or swaged so that the chain cannot be disassembled without cutting off the pin.

Rivet & washer: fasteners used to attached a chain to the outside edge of a curved conveyor belt.

Roll: a rotating component of a belt conveying idler. See Roller.

Roller: (1) a round part free to revolve about its outer surface. The face may be straight, tapered, crowned, concave or flanged, corrugated, ribbed or fluted; (2) a component part of a roller chain in which it may serve only to reduce frictional loss occurring as the chain passes over the sprockets. Rollers may also serve as the rolling support for the chain and the load being conveyed; (3) the rotating element upon which a conveyor belt or chain or the object being transported is carried. See Belt idler.

Roller bed: a series of rollers used to support a conveying medium.

Roller centers: distance between center lines of adjacent rollers. For curves, roller centers are measured at the inside radius.

Roller chain: a chain having a roller encircling the barrel or bushing of each link joint. See Steel side bar bushed roller chain; Transmission roller chain.

Roller conveyor: a series of rollers supported in a frame over which objects are advanced manually, by gravity, or by power.

Roller conveyor curve: a circular section of roller conveyor.

Rough top belt: a belt cover intentionally made with irregular ridges or projections to produce a broken surface for greater traction or carrying abilities. Used for inclined service.

Rubber tire bearing: rubber covered bearings that are used as return wheels.

Run: the distance or route covered by a conveyor.

Run-in: includes final alignment of components, distribution of lubricants by the relative movement of parts and the initial wear between mating surfaces resulting in free running.

Screw take-up: (1) a take-up in which movement of the bearing block is accomplished by means of a screw; (2) a take-up assembly having provision for manual adjustment by one or more screws to compensate for stretch, shrink, or wear of a conveying or power transmission medium.

Self-aligning roller bearing: a roller bearing capable of accommodating shaft misalignment through design of the roller elements or the housing.

Self-cleaning: a conveyor is self-cleaning if, by operating for a time after the feed is shut off, it will deliver substantially all material contained in it to the discharge point.

Sequence starting: an arrangement of interlocking controls for a series of conveyors by means of which the conveyor at the final discharge end is started first to be followed in sequence until the last conveyor at the loading end is set in motion. The order of stopping the units of such a series is directly opposite to the sequence for starting. The conveyor under the loading end is stopped first and the conveyor at the final discharge end is stopped last. This arrangement prevents any pile-up of material in the transfers between the various units of the system.

Service factor: the amount by which the normal rating of a unit is altered to compensate for increased service requirements.

Shaft: a bar, usually of steel and usually round, to support rotating parts or to transmit power.

Shaft deflection: the amount of bending that occurs when an overhung load is placed on a drive shaft extension.

Shaft-mounted drive: a drive unit where the gear reducer is mounted to the drive shaft of the conveyor by means of a hollow output shaft.

Shear pin: see Shear pin device.

Shear pin device: a safety device assembly designed with a free driven component such as a wheel, sheave, sprocket or gear connected by a pin to a driving component such as a hub. The pin must be of a diameter necessary to drive the conveyor within safety limits and must shear when that safety limit is exceeded. When the pin shears, the driving component is disconnected from the driven component.

Shear pin hub: see Shear pin device.

Shear pin sprocket: see Shear pin device.

Shear point or line: the point at which, or the line along which, a moving part meets or passes close enough to a stationary part or objet so that parts of the human body or other objects can be caught, trapped, or pinched between them.

Sheave: a wheel with a grooved rim used with ropes, cables, chains, belts, etc.

Side bow roller chain: roller chain designed for side bending to a relatively large radius for use in powered curves.

Side frame: members that support the slider bed on the sides of the conveyor

Sideguard: vertical panels paralleling the path of a conveyor and limiting the product on the conveyor to movement in a defined path.

Side-mounted drive: a drive assembly mounted to the side of the conveyor, normally used when minimum elevations are required.

Single width chain: a chain having one row of links.

Singulation: where packages are automatically separated while traveling down the conveyor.

Skate-wheel conveyor: a type of wheel conveyor making use of series of skate-wheels mounted on common shafts or axles, or mounted on parallel spaced bars on individual axles.

Skived splice: a type of belt splice where the ends of the belt segment overlap each other. The belt ends must be shaved so the finished thickness of the splice is the same thickness as the belt.

Slat: a member supported between chains in a slat conveyor. The series of slats form the conveying bed.

Slat conveyor: a conveyor employing one or more endless chains to which non-overlapping, non-interlocking spaced slats are attached.

Slave drive: a conveyor drive powered from' another conveyor instead of having its own prime power source.

Slick top belt: a belt material with a low friction top cover.

Slide: a sloped surface to permit free flow of bulk material, packages or objects without particular confinement or restraint at point of discharge. Similar to a straight chute, but without restraining sides or top. See Chute.

Slider bed: a stationary surface on which the carrying run of a belt conveyor slides.

Smooth product transfer: an arrangement of two conveyors so that a product passes across the gap between the conveyors without effecting the product flow.

Snub drive: a drive where the arc of contact with the drive wheel or pulley has been increased by the use of a snub wheel or pulley.

Snub pulley: any pulley used to increase the arc of contact between a belt and drive or tail pulley.

Snub roll: see Snub pulley.

Snub shaft: a shaft that supports a snub wheel or snub pulley.

Soft start: an electrical device that gradually increases the speed of the drive unit upon startup.

Solid woven conveyor belt: a type of conveyor belt wherein the carcass is a single ply consisting of multiple layers of warp and filling yarns interwoven. The carcass usually is impregnated and/or coated with rubber or plastic.

Sortation: a unit handling conveyor system made up of three subsystems: Merge (consolidate), Induct (gap and identify), and Sort (distribute) for processing materials at rated capacity.

Sort conveyor: a conveyor which receives mixed unit loads and discharges them to segregated spaces or conveyors in response to an automatic dispatch control.

Sorting conveyor: see Sort conveyor.

Sorting table: any horizontal conveyor where operators along its side(s) sort bulk material, packages, or objects from the conveyor.

Spare parts: repair parts kept on hand for ready access and rapid repair or maintenance of equipment

Speed: the length of belt, chain, cable, or other linkage which passes a fixed point within a given time. It is usually expressed in terms of "feet per minute", "meters per minute" or "meters per second".

Speed reducer: a power transmission mechanism designed to provide a speed for the driven equipment less than that of the prime mover. Speed reducers may have either constant speed or adjustable speed. They are generally totally enclosed to retain lubricant and prevent the entry of foreign materials.

Speed-up conveyor: a powered conveyor operating at a higher speed than its feeder to create space between unit loads.

Spiral belt conveyor: a belt conveyor which follows a helical path, wherein the input is at a different elevation than its output.

Spiral chute: a continuous curved trough over which bulk materials or objects are guided while being lowered by gravity in a substantially helical path.

Spiral curve: a conveyor section that has both a horizontal and vertical change in direction.

Spiral-Lift: a spiral curve or multiple spiral curve supported by a center support structure.

Splice (Belt): a joint or junction made by lapping or butting, straight or on a bias, and held together through vulcanization or mechanical means.

Spring take-up: a take-up mechanism where adjustments are made automatically by the potential energy of springs.

Sprocket: a wheel with suitably shaped and spaced cogs or teeth to engage with the links of a chain.

Sprocket alignment: the positioning of sprockets in relation to each other so that the chain path is centered on both sprockets.

Sprocket ratio: the ratio between the number of teeth of the driven sprocket to the driving sprocket.

Static conductive: a measurement of the electrical conductivity of a belt material where the resistivity is less than 105 ohms.

Static dissipative: a measurement of the electrical conductivity of a belt material where the resistivity is greater than 105 ohms, but less than 109 ohms.

Static load: force on the supporting structure resulting from the weight of equipment plus material when not operating.

Step ply: a belt carcass in which the number of plies at the center line is less than the number at the edges. It gives the carcass increased lateral flexibility and provides additional cover thickness along the center of the width, where abrasion is most severe.

Straight return roll: cylindrical return roller

Stretch: the temporary change in length of a conveying medium such as belt, chain, or cable. Stretch varies directly with tension in the conveying media. Stretch is usually measured as a percentage of length and is a function of the working load, environmental and ambient conditions. See Elongation.

Supports: arrangement of members used to maintain the elevation or alignment of the conveyor. Supports can take the form of hangers, floor supports, or brackets and can be either stationary or portable.

Sweep: a device across the path of a conveyor placed at the correct angle to deflect objects. Synchronous motor: an electric motor which transforms electric power from an alternating current system into mechanical power. Synchronous motors have direct current field excitation and maintain constant speed.

System: an assemblage or combination of pieces of equipment (conveyor or other) which interact to accomplish a coordinated result. The system may be automated, mechanized, computer, or manually controlled. The term "system" does not denote the level of responsibility between user and vendor for accomplishing the coordinated result required of various pieces of equipment.

Tail end: usually the end of a conveyor nearest the loading point.

Tail frame: the structure which supports the machinery components at the tail end of a conveyor.

Tail pulley: a pulley mounted at the tail end of a conveyor.

Tail section: the frame or structure at the tail or loading end of a conveyor.

Tail shaft: the shaft supporting the tail end pulley, sprockets, sheaves or other components at the tail end of a conveyor.

Take-away conveyor: an adjacent conveyor within a conveyor flow that takes the product away from the conveyor exit.

Take-up: the assembly of the necessary structural and mechanical parts which provides the means to adjust the length of belts, cables, chains, etc., to compensate for stretch, shrinkage, or wear and to maintain proper tension.

Take-up belt tension: the actual amount of tension in each of the two runs of conveying medium approaching and leaving the take-up.

Take-up pulley: a pulley mounted on the take-up shaft.

Take-up shaft: the conveyor shaft which is moved along by the take-up as it is actuated.

Take-up sprocket: a sprocket mounted on the take-up shaft.

Tapered roller: a conical conveyor roller for use in a curve with end and intermediate diameters proportional to their distance from the center of the curve.

Taper lock bushing: a sprocket or end roll hub that is designed to squeeze the shaft as it is installed.

Terminal: a term normally applied to the extreme ends of a belt system, i.e., head and tail pulleys.

Tight side belt tension: in a belt system, where the two portions of a length of a belt on either side of a driving or driven pulley have different tensions, the tight side tension is the greater of the two.

Tolerance: the limit of allowable departure from a designated value of performance.

Top cover: the cover on the material conveying surface of a rubber or plastic belt.

Torque arm: an arm that is attached to a bracket on the conveyor side frame and holds the position of a shaft-mounted gear reducer.

Torque arm drive: a type of drive incorporating a shaft-mounted speed reducer in which the developed torque is resisted by a pivoted connecting link between the reducer and a fixed anchor point.

Torque limit control: a motor control assembly incorporating a torque sensing device which transmits a signal to the associated control components which are arranged to correct and maintain a preset torque value. When sensing current, this device is also known as a current limit control.

Torque limiting coupling: a type of overload release coupling which slips when the torque transmitted exceeds a predetermined value.

Torque pin: a pin that connects the torque arm to the torque arm bracket.

Tracking: see Training.

Training: the process of adjusting idlers, pulleys, and loading conditions in a manner which will correct any tendency of the belt to run other than centrally.

Training idler: see Belt training idler.

Trajectory: the path described by material freely discharging from a conveyor unit.

Transfer: see Transfer mechanism.

Transfer capacity: rate at which unit loads can be transferred through merging or diverging switches or transfer mechanisms in a given period of time.

Transfer distance: the distance between the end rolls on two adjoining conveyors.

Transfer gap: see Transfer distance.

Transfer mechanism: any device that transfers objects onto or off of a conveyor line or from one conveyor line to another.

Transfer plate: a flat steel plate used to fill in the gap between the end rolls of two adjoining conveyors.

Transfer roll: a roller that is positioned in the gap between two conveyors in order to aid in products transfering from one conveyor to another.

Tray sorter: a conveyor consisting of a continuous series of trays attached to a chain(s), each tray being capable of carrying a unit load, and by tilting the tray, will discharge the load from the conveyor.

Trim-lok: a plastic protective strip that is installed on the edge of sheet steel to prevent injury.

Ultimate strength: as applied to chains, belts, or other linkage is the total tensile force which must be applied to cause failure of the part under stress. Ultimate strength may be expressed in pounds; in terms of strength per square inch of cross section, pounds per ply inch, etc.

Underguarding: sheet or mesh material placed on the bottom side of a conveyor to prevent contact with moving components during operation.

Unloader: a conveyor designed to receive the discharge directly from a truck or rail car. Variable speed drive: see Adjustable speed drive.

V-belt: a belt with a trapezoidal cross section for operation in grooved sheaves permitting wedging contact between the belt sides and groove sides for power transmission.

Vent plug: a device that equalizes the internal and external pressures in a gear reducer. A vent plug normally must be installed after a gear reducer in mounted, but before it is operated.

Vertical conveyor: any conveyor that carries only inanimate objects vertically from one elevation(s) to another elevation(s).

Vulcanized endless seam: a belt splice where belt segments are fused together using heat to make a one-piece conveyor belt.

Washdown: construction of conveyors, motors, gear reducers, etc, so that their operation is not effected by water spray.

Weather cover: a removable cover placed over the carrying run of a conveying medium to protect it from the weather.

Wiper: see Scraper.

Wire mesh conveyor belt: a flexible belt composed of a series of formed wires laterally connected, or of longitudinally articulated wires laterally connected for operation over straight face pulleys. Sometimes chains are attached to the edges of the wire mesh and, by means of sprockets attached to the pulley shafts, provide positive belt motion.

Working load: a load rating beyond which a conveying medium should not be stressed.

Wrap: see Arc of contact.

Upcoming Events