Wednesday, 26 February 2020, 4:54 PM
Site: IMI eLearning
Course: IMI eLearning (IMI eLearning)
Glossary: Automotive Glossary
U

Unsprung Mass

The part of the vehicle not supported by the suspension springs. The road wheels, hubs, brakes and part of the suspension system.

Unsprung Mass (Weight)

The part of the vehicle not supported by the suspension springs. The road wheels, hubs, brakes and part of the suspension system.

Up Draft

A carburettor where the choke tube (venturi) is fitted vertically and the air enters from the bottom. Upwards movement of air.

Upper Beam

The upper of the two headlamp beams. Also driving beam and main beam.

Upper Control Arm

The upper and shorter wishbone in an independent suspension system.

Upper Quartile

Data is split into 4 equal quarters. The highest quarter is referred to as the Upper Quartile. For example the Upper Quartile of 100 is the highest 25 of the numbers.

Urethane

A type of paint or polymer which results from the reaction of an isocyanate with a hydroxyl containing component. Urethanes are noted for their toughness and abrasion resistance.

USA

United States of America: North American republic containing 50 states - 48 states in North America plus Alaska in northwest North America and the Hawaiian Islands in the Pacific Ocean; achieved independence in 1776.

UV

Ultra violet.

UV Stabilizers

Chemicals added to paint to absorb the ultraviolet radiation present in sunlight. Ultraviolet radiation decomposes the polymer molecules in a paint film and thus UV stabilizers are used to prolong paint life.