Tyres are an important safety component of any wheeled machine, however, their condition is often overlooked. Because tyres are the only contact your vehicle or machine has with the surface it’s operating on, they need to respond accurately to steering commands and cope with the stress associated with braking, cornering and accelerating. Here are some important things to consider when inspecting tyre condition.
Above all, tyres need to keep vehicles safely and securely on the operating surface in different conditions including when dry, wet, slippery or covered in snow and ice. Tyres should be inspected regularly as part of a proactive maintenance regime and both tyres and wheels must be part of any daily pre-start checklist.
It’s important to keep the right amount of air pressure in your tyres (including your spare). Correct pressure helps to ensure optimum braking performance and minimises wear. Correct pressures also optimise comfort, handling and fuel economy.
Under or over inflation reduces the ability to grip properly, which impacts upon braking capability. This not only causes uneven tread wear but also has a significant influence on handling. If inflation is not adequate for the load the tyre temperature increases due to flexing. Excessive temperature can result in structural damage to the tyre.
Tyres must be inflated to the pressure recommended by the manufacturer and checked on a regular basis when the tyres are cold.
Tread wear issues can appear as flat spots or areas of rapid wear on the tyre. Tread wear issues are commonly caused from brake issues, suspension or alignment problems, and unbalanced tyre from misuse.
Tyres have tread wear indicators and these are important tools for judging remaining tread depth. The indicators include raised bars in the main longitudinal tread grooves that are distributed evenly around the circumference of the tyre, which become level with the rest of the tread pattern once the minimum tread depth is reached. If uneven tyre wear is identified, and the minimum depth has not been reached, tyre rotation is a practical option to reduce the risk and increase the life of the tyre.
If the minimum tread depth has been reached the tyre must be replaced. Any damage such as exposed wire, gashes in the tread or smooth spots means the tyre must be replaced. Smoothness is only acceptable on solid tyres that are designed to be smooth, such as those fitted on some self-propelled elevated work platforms.
It is important to inspect the sidewalls of tyres, which includes both external and internal sidewalls. Inspectors must ensure that they make the effort to inspect internal sidewalls. Sidewall damage can appear as cuts, tears, bubbles or scrapes anywhere along the sidewall of the tyre. This type of damage commonly occurs when a tyre encounters an unexpected hazard, which can include anything from rocks and curbs to pieces of metal.
Sharp objects or concentrated stress usually cause cuts and tears. Bubbles and scrapes occur due to impact damage or prolonged abrasion. Any sidewall damage should be inspected regularly and a judgement needs to be made regarding the need to replace a tyre. Tyre suppliers are able to assist in making judgements regarding the extent of damage and whether a tyre should be replaced.
Separations can appear as bulges on the shoulder of a tread face, or as a localised wear above the separated area. A groove worn along the shoulder could be a sign of separation. Separations are mainly caused by excessive heat during prolonged high speed driving, when a vehicle or trailer is overloaded or of tyres are under inflated. If tyre separation is visible the tyre must be replaced.
Wheel nuts must be checked regularly to ensure they are tightened to the correct torque. Improperly torqued nuts or bolts can result in wheel assemblies coming off, brake damage or broken/stripped nuts, bolts and studs. There are many different wheel-nut indicator systems available that identify when a nut is loose or damaged. Torque settings should be as per the manufacturer’s guidelines.
How does Plant Assessor help with inspection of tyres?
Plant Assessor risk assessments and pre-start checks include specific questions in relation to the inspection of tyre condition. Assessors need to answer these questions, capturing suitable comments and photos in the event that a deficiency needs to further identified, examined and rectified.
As usual, when conducting an inspection, assessors should err on the side of caution and when unsure answer no to the question, which will flag the issue for further investigation. Assessors need to follow their usual lock out/tag out procedures if any significant deficiency is identified during an inspection.
Plant Assessor reports, which are immediately available following completion of an assessment, contain comprehensive risk ratings to assist in making a decision on whether or not to tag out a piece of equipment.
In summary, when inspecting tyre condition, assessors need to consider the following important aspects:
- Tyre pressure
- Tread wear
- Any damage to the tyre
- Any damage to the wheel or components
- Wheel nuts are securely fastened
Disclaimer: This information is intended to provide general information on the subject matter. This is not intended as legal or expert advice for your specific situation. You should seek professional advice before acting or relying on the content of this information. Please contact us for further assistance.
Lauren Butler is the assistant editor for Utility Magazine. She’s based in Melbourne, Australia.