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 Magna characteristics. It is a function of load of each tyre and the number of kilometres covered per hour by each type of tyre, and are given at an ambient temperature of 38C (100F).

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 TMPH = Higher Heat Resistance (better for lang 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-kilometer-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 TMPH, calculated several samples, should not exceed the tyre TMPH rating. If vehicles have on-board operation monitoring systems, we recommends utilizing 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 TMPH rating data are applicable in the following situations.

• Ambient temperature at 38°C (100°F). If revised TMPH at various temperature is needed, please refer to (4) below.
• One way distance within 16 km (10 miles).
• Maximum speed: 50 km/h (30 mph), please refer to (5) when maximum speed exceeds 50 km/h.

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