Extreme operating conditions tests

On-road

Extreme operating conditions tests involving an on-road vehicle were performed on a track at RDW’s Test Center in Lelystad in The Netherlands. The tests involved the wheel joints of a 3-axle extended trailer being secured with Nord-Lock wheel nuts. The truck was then driven in both directions on the test center’s oval track with concave, banked curves in order to exert the same stress on all wheel joints. The Nord-Lock wheel nuts were not retightened after 100 km of driving in order to simulate human error in combination with a worst case driving scenario.

Test vehicle data:
Trailer: NBT, 3-axel bogie by BPW, (adapted for forklift)
Truck:Scania R380
Vehicle total weight:45 000 kg
Tires:Michelin
Rims:Michelin steel rims
Corner speed at test:86 km/h
Track specifications:
Length of test track:2850 m71/320/EEC
Curve radius:160 mECE R13/R13H
Curve gradients:5%, 30% and 60%ECE R39
Maximum axle load:15 000 kgECE R78
Friction coefficient:
Longitudinal gradient:0%

Off-road

For the extreme operating conditions test involving an off-road vehicle, the wheel joints of an 8-wheeled truck were secured with Nord-Lock wheel nuts. During these tests, the following maneuvers were performed to maximize the load on the axles and wheel joints:

• Driving at accelerated speeds over boulders until failure of the vehicle or wheel nut loosening
• Entire vehicle weight was carried by: the rear axle only, the front axle only, and each side.
• Vehicle slid down the hill repeatedly

Test vehicle data:
Truck:MAN TGS 35.480
Power output:600 bhp
Gears:32 gears
Drive chain:8-wheel drive with all axles lockable

Results

There was no signs of wheel nut loosening. The Nord-Lock wheel nut safely secured the wheel joints even under severe on-road and off-road conditions.