The Castor and Wheel Jargon Buster

07 Mar 2018

Working in the castors industry is sometimes a communication nightmare, everyone has 10 words or phrases for the same thing so we thought that we would help you crack the code by writing this jargon buster, so you know where to come when you’re being baffled by jargon!

If you have any suggestions, or know of anything that we’ve left out, we’re keen to know about it!

Axle: The supporting shaft which a wheel or a set of wheels revolves on.

Bearing: Known as either the swivel bearing or the wheel bearing. Bearings enable a castor to swivel freely, and can also be used for added roll ability within a wheel.

Bolt Hole: The single mounting hole in the ball race of the castor that are used to secure the castor to a product.

Bore: The centre hole of the wheel where an axle passes through.

Brake: Stops or prevents the movement of the wheel. Various styles of brakes are available for a variety of different applications (i.e. total lock, friction, tread lock, etc.).

Capacity: (Or Load Capacity) The maximum load per castor or wheel (please note that there are different types of capacity ratings- such as dynamic load rating, impact load rating, and static load rating).

Castor/ Caster: A wheel fastened within a mounting rig that is attached to a product in order to provide a mobility solution.

Directional Lock: When this type of brake is applied, only the swivel section of the castor locks to a rigid straight position to help aid in easy steering.

Durometer: A measurement of the hardness of the wheel tread.

Dynamic Load Rating: A load rating that describes the overall capabilities of the castor. The dynamic load rating consists of durability testing at the established rating, 2x the rating in impact testing, and 4x the rating in static load testing. All Revolution castors are rated as dynamic load.

Fastening: The method of which a castor is mounted to a product. Typical fastenings include top plates, threaded stems, and grip ring stems.

Friction Brake: A style of brake that when applied pinches the legs of the horn together to create friction against the wheel hub.

Horn: The castor parts that comprise legs, plus a base.

Hub length: The measurement through the bore to each side of the wheel.

Kingpin: A rivet or threaded bolt that securely holds the mounting plate, bearings, and horn assembly securely together allowing for swivel ability.

Legs: The axle support brackets that extend down from the horn base or mounting plate.

Offset: (Or Swivel Lead) the perpendicular distance between the vertical centrelines of the king pin and the axle of a swivel castor.

Overall Height: The vertical distance from the bottom of the wheel to the top of the mounting plate (stem versions measure differently based on the style of stem).

Rigid: Another term for stationary or fixed castor. The Rigid castor can roll forward or back, but it’s restricted from swivelling 360˚.

Rig: A swivel or rigid castor assembly less the wheel and axle.

Roll Resistance: The ease of starting the rolling motion of a castor.

Stem: A fastening method on the castor used to mount the castor to a product. Typical stems include grip ring stems, threaded stems, grip neck stems, expanding stems, etc.

Swivel Lock: When applied, it converts a free swivelling castor into a rigid castor scheme.

Swivel Raceway: Single or double rows of ball bearings which support the swivelling movement of the castor.

Swivel Radius: Horizontal measurement from the middle of the kingpin to the edge of the wheel.

Thread Guard: The piece of metal or plastic covering the wheel to prevent dirt, threads, and other debris from attaching to the wheel.

Total Lock: When this style of brake is applied, it locks both the wheel and swivel of the castor simultaneously.

Tread Lock Brake: A brake that when applied locks securely down onto the tread of the wheel.

Wheel Diameter: The nominal diameter of the wheel, this typically describes the basic size of the castor, usually in mm or inches

Wheel Tread: The outside material composition on the wheel which rolls directly on the ground.

Wheel Core: The inside material composition on the wheel in which the tread is formed onto.

Tread width: The width of the wheel when held upright.

Yoke: Another term for horn.

Toe Guard: A protective Steel cover around the wheel of the castor to avoid contact with users’ feet

Top Plate: Also known as 4 Bolt fixing, square plate, Standard Plate

Ball Race: This is the term used for the circle of ball bearing which are set into the head of the castor enabling the swivel motion. As the bracket duty increases you will see taper and thrust bearings used more often.

If you have got any requirements for castors or wheels, please contact the Revolution team today on 01457 832516