TKPH and Compound of OTR Tyres

What is TKPH?

The TKPH stands for Tonne Kilometres per Hour and is an essential expression of the working capacity of a tyre. It represents the load capacity of a tyre in relation to heat generation. A tyre's TKPH depends on its design and varies according to size, type and compound.

How is it calculated?

TKPH values are given along with other characteristics. It is a function of the load of each tyre and the number of kilometres covered per hour by each type of tyre, and is given at an ambient temperature of 38C (100F). Learn more in this article.

Why is it important?

Tyre selection is one of the most important factors for tyre life. Choosing the correct tyre specification with the most appropriate TKPH rating for site operations can significantly improve tyre life and reduce vehicle operational costs.

• Higher TKPH = Higher Heat Resistance (better for long haul cycles) and Lower Wear Resistance (bad for worn out tyre life)
• Lower TKPH = Lower Heat Resistance (bad for long haul cycles) and Higher Wear Resistance (good for worn out tyre life)

How to use Ton-kilometre-per-hour?

The most suitable tyre specifications for the job should be selected by determining TKPH under actual working conditions. This can be obtained by observing the following conditions:

1. The average operating TKPH, calculated from several samples, should not exceed the tyre TKPH rating. If vehicles have on-board operation monitoring systems, we recommend utilising such data for improved statistical estimation.

2. Awss (average work shift speed) must be used.

• Working hours during the shift is defined as excluding ''break time for shift change'' and including ''break time within shift.''

3. The TKPH rating data are applicable in the following situations.

• Ambient temperature at 38°C (100°F). If revised TKPH at various temperatures is needed, please refer to (4) below.
• One way distance within 16 km (10 miles).
• Maximum speed: 50 km/h (30 mph).

4. Revising the TKPH subject to change in maximum ambient temperature.