Wheel Nut

What a Nord-Lock wheel nut is

A Nord-Lock wheel nut is a class 10 wheel nut permanently connected to two Nord-Lock wedge-locking washers. The washers have cams on the facing sides and radial teeth on the outer sides. When the nut is tightened, the teeth grip the nut and the rim, so any movement can only happen across the cams; because the cam angle is greater than the thread pitch, the wedge effect of the cams blocks the nut from turning loose. Nord-Lock describes it as securing the joint with tension instead of friction, and says that when assembled correctly the nut cannot loosen by itself.

Hobson distributes them and lists them for flat-faced steel rims on heavy on-road vehicles such as buses, trucks and trailers, off-road vehicles such as tractors, forestry machinery and military vehicles, and farming and mining equipment. They come pre-lubricated and coated in Delta Protekt for corrosion resistance, and fit standard wheel tools.

Will they fit your wheels?

• •Seat: Nord-Lock designs these nuts for flat-faced rims. Check your wheel's seat type and the vehicle maker's wheel nut specification before fitting.
• •Aluminium rims: Nord-Lock says yes, as long as the rim is flat faced and designed for standard wheel nuts.
• •Thread: M18 x 1.5 or M22 x 1.5 metric fine. Measure the stud or check the vehicle maker's parts list. Hobson lists no left-hand thread version.
• •Spanner: 27mm hex on the M18 and 32mm on the M22.
• •All studs: Nord-Lock says to fit Nord-Lock wheel nuts to every stud on the wheel, so the clamp load is kept across the whole wheel. Order enough for every stud.
• •Ratings: Hobson publishes no load rating for these nuts. Wheels are safety critical: the nut, stud, rim and torque must match the vehicle or trailer maker's specification, and the wheel must be fitted to their procedure.

Wheel nut sizes and dimensions

Both sizes we carry. Select a row to open that nut.

Wheel nut torque and fitting

Tighten to the torque the vehicle or wheel maker specifies: Nord-Lock designs its wheel nut to be tightened at the same torque as conventional wheel nuts. Nord-Lock's own figure, for the M22 x 1.5 only: 600 to 650 Nm with the nut as supplied (pre-lubricated), or re-lubricated on the threads and under the flange when reused, tightened with a calibrated torque wrench in the wheel maker's sequence, gives a clamp load of about 200 kN. Where the vehicle or wheel maker specifies a torque, use theirs. Neither Nord-Lock nor Hobson publishes a figure for the M18 x 1.5, so use the vehicle maker's torque for it.

1. Place the rim over the hub and check the wheel studs are not damaged and the threads are free of dirt and particles.
2. Fit the nuts (pre-lubricated as supplied; re-lubricate the threads and under the flange on reused nuts) and tighten them with a calibrated torque wrench to the recommended torque, in the tightening sequence the vehicle or wheel maker gives (Nord-Lock's manual illustrates the sequences).
3. Impact or pulsating tools can be used, but Nord-Lock notes a calibrated torque wrench is the more accurate way to tighten.
4. Retighten as normal. The nuts do not lose clamp load by rotating, but settling in other parts of the wheel assembly can, so Nord-Lock recommends keeping standard retightening procedures.

Removing and reusing them

• •The nut takes less torque to undo than to tighten, because it slides on the low-friction cam faces when undone. So the undoing torque cannot be used to tell how much clamp load was left.
• •They can be reused. Inspect the nut, the cams and serrations, and the wheel studs first: no damage and no particles in the threads.
• •Re-lubricate the threads and under the flange before reuse, as Nord-Lock recommends.
• •How many times they can be reused depends on the conditions of use, and Nord-Lock's lifetime warranty does not apply to reused nuts.

Delta Protekt coating

The nuts are coated with Delta Protekt, a zinc and aluminium flake coating (base coat KL 100, top coat VH 302 GZ), rated by Nord-Lock to 600 hours of salt spray testing to ISO 9227. Nord-Lock's Delta Protekt sheet, written for its washers, says the coating is applied by dip spin, not electroplating, which removes the risk of hydrogen embrittlement, and that temperatures above 180°C affect its corrosion resistance.

Wheel nuts in Adelaide

Allmat supplies Nord-Lock wheel nuts and washers to transport operators, fleet workshops, farmers and contractors across Adelaide and South Australia. Tell us the thread and how many studs you need to cover, and we will price the lot.

Questions