Faultless History

CASTER INFORMATION
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CASTER TERMINOLOGY
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1. Overall Height - The vertical distance between the floor and
the mounting plane of the equipment.
2. Offset - The horizontal distance between vertical center lines
through the kingpin and the wheel center. (Not shown in diagram.)
3. Swivel Radius - The horizontal distance from the vertical
center line of the kingpin to the outside edge of the wheel tread.
This dimension specifies the minimum distance required for the
caster to swivel 360° when mounted.
4. Wheel Diameter
5. Tread Width
Steering - Steering is affected by the type of wheel, tread, and swivel. Swivel offset is a factor in ease of
steering. Too short a lead will increase steering effort, but too much lead can reduce load capacity and may
cause wobble.
Dynamic or Rolling Load - The load imposed upon a caster or wheel while in motion.
Static Load - The load imposed upon a caster while it is stationary.
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Impact Load - A momentary load imposed upon a caster or wheel when a load is dropped on the equipment
or it strikes an obstruction or experiences vibration.
Rollability - Rollability is the ease with which a wheel or caster can be rolled. Rollability is affected by wheel
size, type of tread and bearings. The larger the wheel, the easier it will roll. A hard, narrow crowned tread rolls
easier than a flat, soft tread on a smooth floor, but may be hard on floors. Soft treads protect floors and pass
over floor obstructions more easily.
Reprinted 7/15/94 with the written permission of The Institute of Caster Manufacturers from “A Guide To Understanding And Specifying Industrial
Casters And Industrial Wheels”