Caster Terms (PDF)

In order to correctly select a caster, one must first become acquainted with the terminology used when referring to casters. Below is a table defining various caster terms that may assist you when choosing the correct caster for your needs.

It may also be helpful to consult the other reference materials Monroe has provided in the casters section of our site. If there are any further questions or concerns, feel free to direct them towards one of Monroe's helpful sales representatives.

Bolt Hole Spacing: The distance between top plate bolt holes. Mounting (Top) Plate: The plate at the top of the caster which is bolted or welded to the equipment. Raceway: Surface on which ball bearings roll. Swivel Radius: Horizontal distance between the centerline of the swivel kingpin and the outside edge of the wheel.
Capacity: Maximum load per caster based on expected operation (expected maximum load divided by number of casters) Fork Assembly (Rig or Yoke): The casterassembly without wheel and axle. Rollability: Force required to begin or maintain motion. Thrust Washer: The washer between the wheel hub and the inside of the caster leg.
Caster Size: Same as wheel diameter. Load Height: Vertical distance from top surfaceof top plate to the bottom of the wheel. Spanner Bushing: The fixed sleeve in which the
axle runs.
TPR: Thermoplastic Rubber
Dynamic or Rolling Load: Load on a caster or wheel while in motion. Offset: Horizontal distance between the centerline of the swivel kingpin and the centerline of the axle. Shorter offsets are stronger while longer offsets improve maneuverability. Static Load: Load on a caster or wheel while at rest. Tread Width (Face): Width of the wheel tread.

Updated: 3/22/2018

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