An alphabetical list of popular terms, and their definitions, are listed below.

If you need help, or have further questions, please feel free to contact us.

If there is a term not listed, and you think it should be, please reach out.

Bolt Hole Pattern: Length and width from the centers of the top plate bolt holes.

Caster Fastener/Fastening Type: Refers to the way a caster is attached to a piece of equipment. (i.e.: top plate, stem, hollow kingpin, and etc).

Caster Type: Swivel, rigid or total-locking frame of a caster. Also referred to as Fork, Rig or Yoke.

Crown Tread: Wheel face that is slightly rounded; reduces surface area & friction. Crown tread helps wheel roll & turn easier.

Double Ball Raceway: 2 sets of bearings rolling in embossed tracks held together with a kingpin; one set supports the load, while the other assists in swivel thrust.

Drop Forged / Hot Forged: A procedure that billet is heated to burning red before being stamped for forming to certain shapes that otherwise could have been done by welding. The process increases the density of metal and further enhances its strength by eliminating any inconsistency of welding. Most of our heavy duty casters are madewith top plate, raceway and king bolts forged to one piece.

Durability: Capacity of a caster to last in demanding applications.

Durometer: System of establishing the hardness of rubber, plastic or polyurethane wheels using either an “A” scale or “D” scale when it is beyond “A” scale’s range.

Dustcap: Metal cap that helps keep foreign materials out of raceways. Dynamic Load: Maximum load of a caster/wheel while rolling.

Ergonomic: Features which improve safety and rollability by providing easier maneuverability or lower rolling resistance. Decreasing push/pull force required to move a caster

Flat Spot: Condition of a wheel tread flattening or compressing without the ability of rebounding to normal shape, causing undesirable rolling condition; happens with overloading or misapplication.

Floor Lock: Accessory used in conjunction with casters; a devise to secure carts from moving on level floors.

High-Temp: Casters or wheels (including all parts), that are capable of operating at higher temperatures without failure or deformation.

Integrally Forged: Different components are made into one single component through hot forging process. The process increases the density of metal and further enhances its strength by eliminating the problem of one or more components failure at severe application. Our Momentum 49 Series has an integrally forged top plate, kingpin and upper raceway. Our Kingpinless casters also have integrally forged top plates & inner raceways.

Kingpin: Bolt or rivet used to hold swivel raceways together; some of our heavier duty drop forged casters have the kingpin integrally forged as one piece with the top plate. Kingpins are typically the weakest point of a caster; kingpinless casters are stronger.

Kingpinless: Casters without a bolt & nut kingpin. A kingpinless caster’s top plate and inner raceway are a one piece construction or integrally forged; the outer raceway with legs attached are held together with the inner raceway by hardened steel ball bearings. This design offers unsurpassed durability and use in abusive and demanding shock load applications that may cause kingpin casters to fail.

Load Capacity: Recommended maximum weight carried by a single caster or wheel under ideal operating conditions. Overloading could result in catastrophic failure.

Mechanical Bond: Method of bonding wheel tread to the wheel core by means of inter-locking materials together.

Mobility: A caster or wheel’s ability to roll freely; many factors are involved, such as wheel hardness, shape, type, bearings, etc.

Mounting Bolt / Attaching bolt: Fastening bolt or screw to attach casters to equipment. Top plate specs will list maximum bolt size. Attaching hardware is not furnished.

Non-Marking: The feature in which a wheel, or caster assembled with a wheel, has a tread that does not leave marks on the floor which it is rolled over.

Overall Height:The vertical distance from the top of the casters fastener (that the equipment rests on) to the bottom of the wheel.

Plain Bore: Wheel bore that rides directly on axle, no bearing.

Raceway: Section of a swivel caster or wheel bearing; bearings that roll in an embossed or machined track.

Roll-ability: A caster or wheel’s ability to roll in its application. The optimum of roll-ability can only be reached by correct selection of caster frames, wheels & bearings.

Seals: Select swivel raceways & wheels may have seals installed to keep debris out and keep grease in. Some wheel bearings are sealed and don’t require maintenance. Check temperature ranges & limitations.

Shock Load: Impact or vibration sustained by caster/wheel from loading or outside forces, such as weight dropped on equipment, equipment running into obstacles.

Thread Guards: Metal or plastic disks that cover wheel hub preventing debris from getting into bearings or wrapping around axle.

Top Plate: A flat metal plate, usually rectangular or square, used to fasten casters to various surfaces.

Top Plate Size: The outside dimensions of a top plate.

Thrust Washer: Washers used between wheel hub and caster leg.

Tread Width: Measurement of a wheels tread from the outside edge to the opposite outside edge.

Wheel: Wheel only, not in a caster frame.

Wheel Diameter/Overall Diameter: Measurement of the outside diameter of a wheel, bearing, tube, socket, etc.

Wheel Material/Wheel Type: The manufacturers/distributors official name of a wheel, or the materials that a wheel is composed of.

Zerk: Grease fitting on wheels, caster raceways or axles.