Best practice wheel fitting- How to stop the 'Wheels coming off' your fleet
With the great number of hours spent on the road, commercial vehicles are extremely vulnerable to stresses and strains. With over 120,500 articulated vehicles registered to the UK in 2015, it should be of little surprise that specific measures need to be taken to minimise the risk of a road traffic accident.
Wheel safety is of the utmost importance, although it continues to be greatly overlooked across the industry. In many cases, wheels become detached from vehicles and result in serious injury or death. Unfortunately, the cause of such accidents is largely down to human error and includes (but is not limited to) early relaxation of tension, low quality replacement parts and careless torque.
In 2015, The Department of Transport published advice in its campaign ‘Careless Torque Costs Lives,’ yet a disturbing number of vehicles still demonstrate poor levels of maintenance. In fact, many continue to regard a missing wheel as a ‘mystery.’
A thorough wheel check should be an important and essential part of your maintenance and should be done regularly. Here are a few generalised safety checks that you should be doing:
- When refitting wheels, lightly oil all wheel fixing threads and lubricate the nut to captive washer interface
- Always use a calibrated torque wrench for tightening wheel fixtures. Avoid using power tools or long bars for final tightening.
- Tighten to vehicle manufacturers recommended torques and procedures in the correct sequence. If a sequence is not quoted, apply the principal of gradually tightening diametrically opposed nuts in turn.
- Check for marks or minor damage in wheels, particularly around the fixing holes, in studs, nuts and washers. If in doubt, renew.
- Check for wear and distortion of wheel and nut seats and seating areas. Over tightening on cone or spherical sets can raise a lip around the edge which, in turn affects seating of twin wheels. If in doubt, renew.
- Check all mounting interfaces; hub mounting face, wheel faces and nut/washer faces must be free from corrosion, damage and dirt.
- Ensure that you pay attention to paint, it might improve the appearance of the vehicle but can prove to be fatal. Paint softens under heat generated from braking and causes loss of clamping of the wheel and looseness. Paint on the interfaces should be microscopically thin.
- Check wheel fixings regularly and thoroughly, ideally at the start of each shift. Wheel fixings can be checked for looseness using a calibrated torque 4 wrench, a socket and short bar. You can also strike the nuts with a small hammer and listen to the noise generated. Ensure that the driver responsible for the check is properly trained.
- In the event of tightening a loose wheel fixing, be sure to try and establish the reason why it has occurred and locate any damage caused.
- Always use trained personnel and document all findings.
Routine visual inspections are an important stage of checking vehicle safety. However, these checks are largely focussed on opinion and experience which can minimise the efficacy of the inspection. Moreover, loose wheel nuts are not always obviously visible and can easily be overlooked. If a wheel nut has loosened, the consequences can be severe.
Parma’s safety indicator products offer a simple solution to this problem by offering high visibility assurance of wheel nut security. Made from high quality plastic that will not melt in normal operating conditions, the indicators are designed to cover the wheel nut and protect from dust, dirt and corrosive traffic grime. Indicators are fitted over adjacent wheel nuts and face each other. Should a wheel nut lose torque, the nut will turn and the indicators will no longer face each other; an ideal visual solution to assure you that nothing is being overlooked.
There are further products that can be combined with visual inspections to further enhance safety and give vehicles an even higher level of security. The Zafety Lug Lock can be added to any bus or truck wheel to minimise the risk of wheel nuts loosening or falling off; its fitting provides a clear visual status of the wheel nuts during inspection and greatly reduces the risk of overlooking potential problems. When nuts have been correctly torqued, the Zafety Lug Lock fits over two adjacent nuts to secure them together. As a high temperature product, it is ideal for vehicles involved in stop/start journeys or on routes that necessitate heavy braking.
Wheel safety should be prioritised by anyone that runs a fleet and should never be compromised. The use of pre-launch visual checks combined with pre-emptive safety products offer an optimal level of safety and help to keep your vehicles on the road, and more importantly, your team’s in safe hands.