How Important is Centre of Gravity for Liquid Transport Tanks?

What is centre of gravity?

Centre of Gravity is the imaginary point at which the weight of the object is concentrated. In real terms, this means where gravity is expected to act upon a certain object so that we can predict the behaviour of it. If something has a high centre of gravity, we expect gravity to act more on the top of an object, if something has a low centre of gravity, we expect gravity to act more on the bottom of an object.


So…Why is it important?
When it comes to stationary objects, centre of gravity is not all that important. However, when it comes to moving objects, it can help us to predict how the object will move. While this is important for predicting the behaviour of moving objects, it becomes all the more important when we’re talking about something that moves around inside an object and changes the weight depending on its movement – which is what liquid does.

When liquid is transported, it moves around the tank, meaning that different areas of the tank become heavier depending on where the liquid has moved to. As a vehicle transporting a tank moves on the road, it shifts the liquid inside to one side or another, meaning that the heaviest point is constantly different as the liquid finds it level.


If you have a high centre of gravity (the greatest weight is concentrated at the top of your tank) this means that driving around corners and up hills allows gravity to have more influence over the weight than if you have a low centre of gravity. A low centre of gravity is important, as this means that as the liquid shifts around, it is less likely to cause tipping and rolling than if you have a high centre of gravity.




So how do we influence centre of gravity?
If you think about it – a circular cross section would allow for more liquid to fit inside the tank than the common elliptical cross section tanks. However, circular cross sections have a much higher centre of gravity, meaning that the risk of rolling the truck is much, much higher when turning tight corners. Interestingly, a rectangular cross section would have the lowest centre of gravity – but due to issues like fitting in lanes and cleaning, the elliptical cross section is the safest and most practical for driving and usage.


Centre of gravity is hugely important when considering buying a transport tank, as this will influence how safe it is to drive, and how likely you are to tip, as well as its ability to climb hills and inclines. This can make a huge difference to safety when it comes to using and transporting liquid fertiliser, fuel or water for firefighting. All TTi tanks are designed carefully to ensure the Centre of gravity is as low as practically possible.