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Maxion Wheels has been supplying OEMs with the highest quality wheels and most innovative technologies for over 100 years.

Glossary

The following industry-specific terms are commonly used when spec'ing or ordering wheels.

Adaptor
The component of a tubeless demountable rim assembly that provides a surface for mating to the bevel (28°) of a cast spoke wheel.
Air Wrench
An air-powered tool designed to tighten and loosen fasteners.
Ball Seat
The spherical area around the bolt holes and on the nuts, used in the stud-piloted mountings to center and clamp the wheel.
Bead Seat (Tire Seat)
The tire-seating surface of a rim.
Bolt Circle (Pitch Circle)
The circle diameter through the center point of the bolt holes.
Bolt (Stud) Hole
A hole in a disc wheel for attachment fasteners.
Butt Weld
The weld running across the rim or other component that joins its ends together during manufacturing to make a hoop.
Cast Spoke Wheel
A casting, usually with 3, 5, or 6 spokes, that provides a means of attaching a demountable rim to a vehicle.
Center Hole
(Pilot Hole, Hub Hole)
The large hole in the middle of a disc wheel.
Clamp Load
The resulting force between the hub or drum and/or wheel after torqueing the wheel nuts.
Cone Lock Nut (CLN)
See Flange Nut.
Demountable Rim
A rim with 28° permanent mountings intended for use on a cast spoke wheel.
Disc (Spider)
The center member of a disc wheel that connects the rim to the hub.
Disc Face
The flat central portion of a disc wheel in which the bolt holes are located, and which contacts the drum, hub or mating wheel.
Disc Thickness
The thickness of the disc in the disc face.
Disc Wheel
A permanent combination of a rim and disc.
Double Cap Nuts (DCN)
Two wheel nuts used in stud-piloted mountings. They include inner cap nuts used to fasten inner wheels to a vehicle and outer cap nuts used to fasten single wheels and outer wheels to a vehicle. These nuts have both left- and right-hand threads, and have ball seats that fit into the wheel ball seat bolt holes to center and clamp the wheels on the hub.
Dual Spacing
The distance from the center of a tire (rim) to the center of the other tire (rim) in a dual tire arrangement. It is determined by adding the two half dual spacings (disc wheels) or two rim offsets plus the spacer band width (demountable rims).
Fixed Flange
The permanent flange on a rim base designed to support the tire.
Flange
One removable component (split, non-continuous) of a two-piece tube-type rim which provides lateral support for one tire bead. It is sometimes referred to as a "split side ring".
Flange Nut
A nut with a flat face or flange that bears against the wheel (can be one-piece or multi-piece).
Half Dual Spacing
The distance from the outside disc face (surface between the wheels as a dual assembly) to the center of the rim. Also see Wheel Offset.
Hand Hole
An opening in the wheel disc area between the disc face and rim.
Hub
The rotating member that represents the attachment face for wheel discs.
Hub Mounting Face
The flat surface of a hub containing the studs that contacts the wheel or drum.
Hub-Piloted Mounting
A wheel mounting system in which location of the wheel is accomplished by positioning the wheel center hole on a machined pilot (continuous or interrupted) on the hub. Fastening is accomplished by flange nuts bearing against the flat face of the wheel disc.
Inner Cap Nut
The ball seat nut used to install the inner stud-piloted dual wheel to a vehicle. The outer cap nut screws onto this nut.
Inset
The distance from the center of the rim to the wheel mounting surface when the rim center is inboard of the mounting surface.
Lock Ring
One removable component (split, non-continuous) of a three-piece tube-type rim, which locks the side ring to the rim base.
Multi-Piece Wheel/Rim
A rim consisting of more than one part, usually two pieces (rim base and flange) or three pieces (rim base, side ring, and lock ring) for use with tube-type tires.
Outer Cap Nut
The ball seat nut used to install the outer wheel of a stud-piloted dual assembly or a single stud-piloted wheel to a vehicle. The outer nut screws onto the inner cap nut in a dual assembly.
Outset
The distance from the center of the rim to the wheel mounting surface when the rim center is outboard of the mounting surface.
Rim
The supporting member for the tire or tire and tube assembly.
Rim Base
The major portion of a rim that remains after all removable components have been detached.
Rim Clamp
A device used to hold a demountable rim on a spoke wheel.
Rim Drop Center (Rim Well)
The portion of a single-piece rim that is made to a smaller diameter than the bead seats to allow mounting of the tire.
Rim Flange
The edge of a rim that has a larger diameter than the tire bead designed to support the tire.
Rim Gutter
The recessed area of a rim base that accepts a locking ring or flange.
Rim Offset
For demountable rims, the distance from the outside of the mounting ring (surface that contacts the spacer band) to the center of the rim.
Rim Size Designation
The characteristic used to describe the rim (nominal diameter, type, nominal width).
Runout
Total indicator reading in the lateral or radial direction, taken at the rim bead seat, for one revolution with the wheel (rim) located on the specified datum.
Side Ring
One removable component (solid, continuous) of a three-piece tube-type rim which provides lateral support for one tire bead.
Spacer/Spacer Band
A metal band that separates two demountable rims on a rear spoke wheel.
Spoke Wheel
See Cast Spoke Wheel.
Stud
A threaded bolt that is used with wheel nuts to fasten wheels or rims to a vehicle.
Stud-Piloted Mounting
A wheel mounting system in which location and fastening of the wheel are both accomplished by nuts which fit corresponding at each wheel bolt hole.
Torque
The measurement of nut tightness.
Torque Wrench
A tool that measures fastener torque.
Tubeless Wheel/Rim
A single-piece wheel or rim with a drop center designed for use with tubeless tires.
Valve Hole
A round hole in a single-piece rim to accommodate the valve stem.
Valve Locators
Embossments located on either side of the rim valve slot or valve hole to properly locate the tire valve stem between the spokes. They are sometimes called "drivers".
Valve Slot
An opening in a multi-piece rim to accommodate the tube valve system.
Wheel Mounting
Surface/Face
See Disc Face.
Wheel Offset
For disc wheels, the distance from the center of the rim to the wheel mounting surface (surface between the wheels as a dual assembly) or calculated as inset plus disc thickness. Also see Half Dual Spacing.
Wide-Base Wheel
A tubeless drop center wheel with rim width of 10.50" or more, for use with wide base tires, typically used either for increased load capacity on steer axles, increased flotation, or to replace dual wheels.

 

IMPORTANT

The terms "rim" and "wheel" are often confused in colloquial speech. This may cause misunderstanding and lead to improper application or incorrect orders. It is important to use the terms properly.