From aspect ratio to virgin tyre, this glossary covers the essential terminology used in the commercial transport industry in Anguilla. Use the search bar or jump to a letter below.
A
- Aspect Ratio
- The ratio between the height of a tyre's sidewall and its section width, expressed as a percentage (for example, 75 in 295/75R22.5).
B
- Bead
- The steel-wire-reinforced edge of the tyre that seats securely against the wheel rim to maintain an airtight seal.
- Belt Package
- Steel-cable plies positioned beneath the tread that stabilise the contact patch, resist punctures and improve handling.
- Bias Ply
- A tyre construction in which the plies cross diagonally over the casing. Largely replaced by radial construction in commercial applications.
C
- Cap-and-Base Compound
- A two-layer tread design that uses a harder top compound for wear resistance and a softer base layer for heat management.
- Casing
- The structural body of the tyre beneath the tread rubber, designed to withstand retreading and deliver multiple service lives.
- Closed Shoulder
- A tread design in which the outer ribs are connected, reducing stone retention and uneven wear on drive-axle tyres.
- CPM / CPK (Cost Per Kilometre)
- Total tyre cost divided by the total kilometres travelled before removal. The standard metric for comparing the value of commercial tyres.
D
- DOT Code
- A serial number moulded into the sidewall that identifies the manufacturer, the production plant, the tyre size and the date of manufacture.
- Drive Position
- The rear-axle drive position(s) of a commercial truck, requiring tyres with deep, aggressive tread for maximum traction.
- Dual Assembly
- A configuration in which two tyres are mounted side by side on a single wheel, common on drive and trailer axles.
F
- FMVSS
- Federal Motor Vehicle Safety Standards -- US-origin standards that govern tyre performance, labelling and safety requirements. In Anguilla, commercial tyres are expected to meet international tyre safety standards such as FMVSS 119 and ECE R54.
- Footprint
- The area of the tyre's tread in direct contact with the road surface at any moment under load.
G
- Grooves
- Channels moulded into the tread surface to evacuate water, dissipate heat and provide edges that improve traction.
H
- HATT
- Hanksugi Advanced Tire Technology -- a proprietary engineering platform that optimises tread compounds, bead strength and casing geometry.
I
- Inflation Pressure
- The air pressure inside a tyre, measured in PSI. Correct inflation is critical for load capacity, wear and fuel performance.
- Uneven Wear
- Irregular erosion of the tread caused by misalignment, incorrect inflation, mechanical problems or running tyres in the wrong positions.
L
- Load Index
- A numerical code that indicates the maximum weight a tyre can safely carry at its rated inflation pressure.
- Load Range
- A letter designation (G, H, J, L) that represents a tyre's equivalent ply strength and its maximum inflation pressure.
- LRR (Low Rolling Resistance)
- Tyres designed to minimise the energy lost to deformation as the tyre rolls, directly improving fuel performance.
- Lug Pattern
- A tread design with deep lateral grooves for aggressive traction, commonly used on drive axles and in off-highway applications.
M
- M+S (Mud and Snow)
- A sidewall marking indicating that the tyre's tread meets Rubber Manufacturers Association standards for traction in mud and light snow.
P
- Ply Rating
- A traditional measure of tyre strength that indicates the cord plies supporting the load. Now replaced by the Load Range designation system.
- PSI
- Pounds per square inch -- the standard unit of measure for tyre inflation pressure used in Anguilla.
R
- Radial Construction
- A tyre structure in which the plies run perpendicular to the direction of travel, providing even wear and flexible sidewalls.
- Retread
- The process of buffing a worn casing and applying new tread rubber, extending the tyre service life at a significantly lower cost.
- Rib Pattern
- A tread design with continuous circumferential grooves, optimised for long highway mileage and even wear on steer axles.
- Rolling Resistance
- The energy a tyre consumes through internal friction as it rolls under load. Lower values translate into better fuel performance.
S
- Sidewall
- The vertical section between the tread and the bead that carries the tyre size, the load rating, the DOT code and the manufacturer's markings.
- Siping
- Fine cuts made in the tread blocks to create additional grip edges that improve wet traction and reduce hydroplaning.
- SmartWay
- An EPA verification programme that certifies tyres meeting fuel-saving and emissions-reduction standards.
- Speed Rating
- A letter code (for example, L, M) that indicates the maximum sustained speed at which a tyre can safely operate under load.
- Steer Position
- The steer axle of a commercial truck, which requires tyres optimised for precise handling, lateral stability and even tread wear.
- Stone Ejectors
- Small raised rubber elements moulded into the tread grooves that prevent stones from becoming embedded and puncturing the casing.
T
- TPMS
- Tyre Pressure Monitoring System -- electronic sensors that monitor continuously and alert drivers when inflation falls below safe levels.
- Trailer Position
- Non-drive axle positions on trailers, which require tyres designed to resist lateral scrub and minimise rolling resistance.
- Tread Compound
- The specific rubber formulation of the tread surface, designed to balance wear resistance, traction and heat dissipation.
- Tread Depth
- The distance from the tread surface to the bottom of the deepest groove, measured in 32nds of an inch.
U
- UTQG
- Uniform Tire Quality Grading -- a DOT grading system that measures tread wear, traction and temperature resistance (mainly for passenger tyres).
V
- Virgin Tyre
- A completely new tyre that has never been used or retreaded, also known as a new or original casing.
