OpenLegislation

Appendix 3

United Kingdom

Original text. Later amendments are not shown.

Calculation of the standard torque loss

The standard torque losses for axles are shown in Table 1. The standard table values consist of the sum of a generic constant efficiency value covering the load dependent losses and a generic basic drag torque loss to cover the drag losses at low loads.

Tandem axles shall be calculated using a combined efficiency for an axle including drive-thru (SRT, HRT) plus the matching single axle (SR, HR).

Table 1

Generic efficiency and drag loss

Basic functionGeneric efficiencyη Drag torque(wheel side)Td0 = T0 + T1 * igear
Single reduction axle (SR) 0,98

T0 = 70 Nm

T1 = 20 Nm

Single reduction tandem axle (SRT) /

single portal axle (SP)

0,96

T0 = 80 Nm

T1 = 20 Nm

Hub reduction axle (HR) 0,97

T0 = 70 Nm

T1 = 20 Nm

Hub reduction tandem axle (HRT) 0,95

T0 = 90 Nm

T1 = 20 Nm

The basic drag torque (wheel side) Td0 is calculated by

Td0 = T0 + T1 * igear

using the values from Table 1.

The standard torque loss Tloss,std on the wheel side of the axle is calculated by

T loss,std = T d 0 + T out η − T out

where:

Tloss,std

  • Standard torque loss at the wheel side [Nm]

    • Td0

  • Basis drag torque over the complete speed range [Nm]

    • igear

  • Axle gear ratio [-]

    • η

  • Generic efficiency for load dependent losses [-]

    • Tout

  • Output torque [Nm]