How do you avoid sideloader accidents?

A sideloader refers to two different pieces of equipment: a forklift that loads to its side, and a lorry that has two cranes to lift containers on and off (e.g. a Megalift, Hammar or Swinglift). This article deals with the latter.

We’ve covered how to avoid problems when picking up a container. This article is about the actual accidents and what causes them.

Because the containers easily weigh more than 25 tonnes, when they fall or tip the vehicle over, there’s a lot of kinetic energy to stop. For this reason, sideloader training is crucial and can be done online.

Rollover

There are four types of rollover.

Container-side rollover

When lifting, the vehicle can roll to the container’s side. This happens for one or more of eight reasons:

1. The crane operator moves the controls too quickly or jerkily, or doesn’t keep the lifting even
2. The ground isn’t level and is actually already leaning towards the container
3. The container is too heavy for the stable base of the lorry or trailer (this is very easy to do if the stabiliser legs aren’t deployed, or the operator is trying to lift a container that the vehicle isn’t rated for)
4. Something in the container moves, shifting the centre of gravity
5. Some other force acts on the container, for example, strong winds either push the container away from the truck or cause the container to swing.
6. Something breaks. This is uncommon, but some older sideloaders don’t have hydraulic leak protection.
7. The stabiliser legs sink into soft ground causing the vehicle to lean
8. The operator forgot to apply the park brakes and the vehicle moves while lifting

Offside rollover

All sideloaders have stabiliser legs that extend to the lifting side (i.e. where you would usually pick up the container). This gives stability when lifting. However, as mentioned above, jerky operation, wind or something that causes the vehicle to lean in one direction can cause the container to swing over the offside of the vehicle. There are bash plates that extend up about a foot above the twistlocks to help seat the castings when lowering the container; these will stop the container swinging but are not very tall.

Some sideloaders have offside stabilisers and these should be used if available.

On-road rollover

The driver usually cannot inspect what’s in the container, so it can often be difficult to understand if a container is unevenly loaded. We covered the dangers of transporting shipping containers here. The only ways to tell are:

• The container has scales on each crane (reliable for end-to-end measurements, but not side-to-side)
• Visiting a weighbridge after it has been loaded (you have to drive a certain distance to get there)
• Inspecting the load (often not possible if it’s sealed)
• Trying to feel if the handling or braking is odd (an unreliable method)
• Looking at how the container sits when loading (is it leaning heavily one way)

If the container is very unbalanced side-to-side, this presents a greater rollover risk when cornering on a road. View this rollover prevention training course for ways to mitigate the risk.

Transfer rollover

Technically, this is still an off-side rollover, but it’s caused by other factors. When transferring a container from another vehicle (in this case, a trailer or lorry, not a rail car), the stabilisers are sometimes rested on the chassis. When the load is removed from the other vehicle, its suspension rises as the weight is shifted across to the lifting vehicle. This can tilt the lifting vehicle to the offside, creating more offside rollover risk. The operator should stop and adjust the stabiliser legs. Dumping the air from the suspension on the other vehicle can prevent this, too.

Breakages and worn parts

There are four main breakages to be aware of.

Chain failure

Older chains that are stretched, bent, gouged or corroded are weaker and more likely to fail. If the chain fails, the container will drop and swing. The container might even roll and, depending on the weight, it has the potential to take the truck with it. The end of the broken chain, which will have been under pressure, will whip back; an impact from this can be enough to kill a person.

Sideloader chains will be certified for a certain date; ensure that the chains are reinspected or replaced. They have a weight rating. As there are four chains, it’s expected that the load would be reasonably evenly balanced. If the load is heavily unbalanced, this will overstress one or two of the chains, increasing the risk it will snap.

Twistlock failure

A big hit by a swinging container can damage a twistlock. However, it’s unlikely it will fail completely. A bigger risk is drivers forgetting to lock them before leaving or unlock them before another vehicle such as a gantry crane or straddle carrier lifts it off the vehicle.

Hydraulic leaks or burst hoses

The hoses are out in all weather and eventually degrade, which is why a pre-trip inspection is an important part of a driver’s routine. Most modern hydraulic systems have a failsafe which stops the crane from dropping if hydraulic pressure suddenly decreases

Lug/corner casting failure

At the end of the chain is a lug that fits into the corner casting. Over time, these get worn and the fit gets sloppy. If it fails, it’s the same type of result as a broken chain, except worse because it breaks at the longest extent of the chain, leading to that chain whipping back with a potentially larger danger zone. Again, inspecting them every day helps avoid this situation.

Crane damage

Drivers sometimes cause damage to the cranes through carelessness. However, these are the four main things to watch for:

• Never move the vehicle while the stabiliser legs are deployed as you can hit something with them, bending them
• Never use the cranes to push or pull a container that’s on the ground as this can bend the components
• When travelling empty, move the containers to the 20-foot position so that the risk of hitting the cranes is minimised.
• Never load a container when the truck is not level – the container can swing into the cranes or the truck, causing damage

All these can lead to weak points while operating the crane which then can cause a failure.

Human risk

Finally, we need to consider the risk to the operator and others around the sideloader. The sideloader will have an exclusion zone in which people should never be while the crane is operating. People have been crushed by the cranes and the container by being in the wrong place at the wrong time.

The operator must use the e-stop to stop the cranes’ movement when a person enters the exclusion zone.