Testing all year round
Testing is an essential element of product development. Nokian heavy tyres undergo versatile testing in genuine working conditions, without cutting any corners or compromising precision. In addition, indoor testing is used for additional data. Testing activities are continuously ongoing around the world.The indoor testing focuses on the tyre’s structural durability, rolling resistance and noise levels, as well as its contact area and surface pressure. In genuine conditions – on fields, in forests, mines and harbours – the tyres are put to a real test. Tests are carried out in different seasons to gain information on such properties as grip, wear resistance and handling properties in different temperatures and on different surfaces.
The aim is not only to meet the required or permitted levels but to achieve continuous improvement and offer our customers safe, efficient, durable and environmentally friendly top-quality products.
Effortlessly forward
Low rolling resistance means that Nokian heavy tyres roll effortlessly, which reduces fuel consumption and lower CO2 emissions. The rolling resistance depends on tyre pressure, as well as on the tyre structure and profile. Rolling resistance is measured, among other ways, using testing machine in which the tyre is pressed against a rolling drum with a certain load, and a sensor detects the torque caused by the tyre. The rolling resistance rate is then computed.Lower surface pressure
Contractors who make their living from the soil or forest value the environmental friendliness and cost efficiency of tyres in terms of how they treat the terrain. On fields, the weight of the machines and footprint left by the tyres cause soil compaction, both in the cultivated layer and in the underlying subsoil. Compaction deteriorates the soil’s cultivation properties, decreases crops and increases the environmental load. Subsoil compaction can have long-term consequences. In the forest, roots can be damaged.The soil compaction caused by tyres at different depths can be monitored using the so-called Cone Index measurement, in which a sensor is pressed into the ground and the values from the tyre track are compared with those of untouched ground. The higher the degree of compaction, the more the soil resists the sensor.
For example, when the aim is to minimise the surface pressure burdening a field, the tyre must have a large contact area. Flotation tyres, for example, have a large contact area but also a low rolling resistance, causing the tyre to roll very effortlessly. Studies have indicated that these tyres save nearly 20% fuel as compared with cross-ply tyres. In other words, the tyres help gain bigger crops, and they also save fuel and, consequently, the environment.
Proven to be more comfortable
Ergonomic working conditions are included in the principle of sustainable development. In addition to driving properties, the elimination of harmful noise and vibration is essential. These properties are measured using a vibration indicator placed in the machine operator’s seat. The lowering of vibration is particularly important in forestry machines and during on-road transition drives.Nokian heavy tyres have proven to be a more comfortable choice. For example, the Nokian Forest Rider forestry tyre has won test after test. The tyres have been tested in co-operation with the University of Helsinki and the Forestry Research Institute of Sweden at the Jämsänkoski Forestry College and on the test track of the forestry machine manufacturer Rottne between 2006 and 2008.
Read more about Nokian Tyre’s testing of passenger car and truck tyres on www.nokiantyres.com.