|
|
|
Axle weight calculation 1) Theoretical exercise (used mainly in CPC examinations) to determine the weight on an axle when other given weights are known. Formula (P x D)/W applies when P = vehicle payload, D = the distance from the load centreline to the axle and W = the vehicle wheelbase.
Axle weight 1) Sum of the weights transmitted to the road surface by all the wheels of a vehicle axle.
Axle spread 1) Distance between the centre lines of the outermost axles (ie the foremost and rearmost axles) on a goods vehicle (see also relevant axle spacing).
Two-speed axle 1) Rear axle of goods vehicle containing two crown-wheel pinions for changing between high and low ratios. Operated from cab by vacuum or electrically. No longer popular with advent of multi-ratio gearboxes. Axle load indicator 1) A built-in device for indicating the weight of the load borne by a goods vehicle axle – intended to help prevent axle overloading.
Axle interspace 1) Legally specified minimum ground clearances for trailers. The distance from point of support on the tractive unit in the case of semi-trailers, or the centre line of the front axle in the case of other trailers, to the centre line of the rear axle or the centre point between the rear axles if more than one.
Gross weight (vehicle/axle) 1) The total weight of a vehicle/trailer or vehicle/trailer combination transmitted to the road by all the wheels. Includes load, driver/passenger, loose equipment and fuel. Tri-axle/bogie 1) Bogie comprising a number of linked axles (usually on trailer). In this case three such axles linked by suspension. Double reduction axle 1) Vehicle rear axle with gearing (ie crown wheel and pinion – differential) designed to provide normal and lower drive ratio. Also double reduction hubs – in heavy goods vehicle to reduce stress on differential and half- (ie drive) shafts. See also Hub reduction. Lifting axle 1) Axle on vehicle/trailer which is designed to be raised from the ground (usually by means of compressed air) to reduce tyre wear and scrub when running empty but to provide full gvw potential when lowered for running loaded. Trailing axle 1) Term for non-driven axle usually in a tandem bogie on goods vehicle (ie provided to enable extra weight to be carried but not needed for traction purposes). Airsprung axle (bogie) 1) Axle or set of axles with suspension provided by air bags (see Air suspension).
Air-lift axle 1) Retractable (ie lift-up) axle on vehicle/trailer lifted from road surface by means of compressed air to reduce rolling resistance (for fuel economy reasons) and tyre wear.
Relevant axle spacing 1) Legal term used in connection with determining the permissible weights for articulated vehicle combinations, namely distance between rearmost axle of drawing vehicle and rearmost axle on semi-trailer. Tandem axle 1) Second axle in a tandem bogie (ie linked by suspension units). See also Trailing axle. |
|
|
|
|