• Dec 17, 2018

The Dukes of Hazard

Tyre replacement and inflation is a daily procedure for the tyre and wheel industry. Millions of tyres are replaced each year, so it may seem a simple task to replace or inflate a tyre but it can be a serious hazard causing injury and death.

The sudden depressurisation of a tyre can release a large amount of energy as a percussive shock wave. For tyre assemblies that have split wheels or multi-piece rims these components can become projectiles following a sudden depressurisation.

The risk of a tyre burst is particularly high during the first inflation of a tyre after assembly or mounting i.e. components (e.g. the bead) fail to engage properly, or the wheel or rim is not correctly assembled. This initial inflation is often undertaken in a workshop or maintenance area. The percussive shock wave and projectiles generated can damage equipment and be potentially lethal to personnel in the "line of fire".

Many tyre inflation cages are purchased or manufactured without comprehensive designer or manufacturer instructions for their installation, operation, inspection and maintenance. During installation, this can lead to mining operators:

• bolting tyre inflation cages to concrete floors or other structures. The bolts and nuts used, the concrete floor or support structure are usually not designed to withstand the forces generated during a tyre burst, and therefore may generate projectiles.
• over-restraining the cage structure which reduces the capacity of the tyre inflation cage to deflect or deform and adsorb the energy of the tyre burst. Most tyre inflation cages are more effective if they are free-standing and should not be bolted down without consulting the manufacturer.

In 1996, RLM Distributing were asked by industry peers to develop a Tyre Safety Inflation Cage, one that would meet with OH&S requirements, while being simple and practical to use.

After months of material research and design engineering, RLM's cage was carefully inspected, then blast tested by WorkCover NSW, resulting in Australia's only fully tested and certified tyre safety inflation cage.

RLM went onto develop several certified models, tailored to meet with different workshop requirements; for general automotive, heavy transport, earthmoving and aircraft tyres.

Safety Tips for Users of Tyre Inflation Cages

1. Do not modify a tyre inflation cage without the approval of the manufacturer.
2. Cages should be freestanding, and at least 500 mm from a solid wall or structure, and a 3 metre personnel exclusion zone to all sides.
3. Permanently mounting an inflation cage to the floor prevents the cage absorbing and defusing the energy released during a tyre explosion.
4. Tyre inflation must be controlled from a minimum distance of 3 metres, using an air regulator, shut off valve, extension hose with a clip-on chuck, and the tyre valve core removed.
5. Never rest or lean on a tyre inflation cage during the inflation procedure.
6. Never allow any part of your body inside an inflation cage during the inflation procedure.
7. If adjustments to the tyre assembly are required, the tyre must be completely deflated before removing the assembly from inflation cage.
8. Operators should be trained in tyre fitment procedure, always wear PPE, and be certain that everyone is outside the exclusion zone.

A Seriously Funny Cage Story

RLM are aware of one occasion where some tyre-workers, let's just call them The Dukes of Hazard, failed to read the instructions regarding their newly acquired RLM tyre cage.
Rather than place the tyre inside the inflation cage, the workers placed themselves inside the 'safety' cage and proceeded to inflate the tyre that remained outside the cage.
We've all heard of cage diving with sharks. It appears we now we have cage diving with tyres!

Researched, composed and written by Dr Steve Gration - December 2018.