How to Calculate TKPH

Before we explain how you can calculate TKPH we first need to specify what we mean by this term and why you need it. TKPH stands for Tonne Kilometers Per Hour. TKPH is a method of answering one of the fundamental questions regarding load transport: How much load can I transport on a set of tires per working hour?

The Tonne Kilometers Per Hour index indicates what your tires can handle. It depends on the compound and materials that are used. A common misunderstanding is that TKPH gives information about the vehicle too. This is not the case. Tonne Kilometers Per Hour has nothing to do with the size of the tire, the type of vehicle or the soil condition it is used on.

The Importance of TKPH

Choosing the right OTR tire for your vehicle is one of the most important factors that determine tire life. If a tire is selected with a deviating TKPH marking, the tire wear will drastically increase and the overall cost of transport will increase too. If you calculate TKPH correctly, your tires will last like they are meant to and maybe even longer!

Calculate Tonne Kilometer Per Hour

The formula for calculating TKPH may look difficult at a first glance, but is actually not that hard to work with.

TKPH = ( mean tire-load ) x ( average work-shift speed )

Mean Tire-Load

As you can see, the formula consists of two parts. In order to figure out the TKPH we need to know the average tire load a vehicle carries. To be more precise, how much is the total weight of the vehicle with and without carrying a load. In this case ‘mean’ means the average weight of a full and an empty vehicle. We add both weights to get a total and then divide it by two to get the average. This gives us the next fairly simple sub-formula:

Mean tire-load = ( tire-load empty + tire-load fully loaded ) / 2

Average work-shift speed

The second half of the formula focusses on the actual kilometers covered during shifts. First we need to know the amount of distance the tires need to cover for a full cycle. To be more plain; how much distance does a tire travel to haul a load from point A to point B and back to point A again. We call that a round-trip or a cycle/shift. To get a total of the covered distance we need to multiply this amount by the number of cycles a tire makes per shift. In order to bring it back to an average work-shift speed we divide the multiplied amount of distance by the total hours of operation per shift. This may look confusing in writing, but if we formulate it as a formula it may be more clear to you:

Average work-shift speed = ( round-trip distance x number of cycles/shift ) / total hours of operation/shift

If you use both outcomes in the first formula you will get a certain number. Congratulations, you just calculated the Tonne Kilometer Per Hour for your vehicle! This number should always be lower than the load index. You can learn how to read your tire here.

In general, a higher TKPH has a higher heat resistance and is more suitable for long hauls. A lower TKPH has a better wear resistance and is better suited for slower speeds and shorter distances. If you wish to know which of our tires would fit your machinery, feel free to contact us! We will gladly help you select the right tire for your machinery.