Quality Tests of Wheels, Rims and Tires

In general, passenger car tires have a complex structure. Rubber tires have been produced for over a century. Today's tires have played an important role in the development of today's steel-belted radial tires. Essentially, tire components are divided into two main structural elements: the tread and belt assembly and the casing. These elements consist of several layers. The outer layers, which form the tread and belt of the tire, mainly the rubber component, envelop the casing and provide low rolling resistance, optimum road holding, long life and good fuel consumption. The tire tread is made of synthetic and natural rubber. The tire tread connects to the road and sidewall and has three areas: The cap is the part of the tire that comes into contact with the road the most. It provides grip, wear resistance and directional stability on all road surfaces. The base is the part located under the cap and reduces rolling resistance and damage to the casing, the internal structure of the tire. The shoulder is an area located on the outer edges of the tread and creates a smooth transition from the tread to the sidewall of the tire.

The cap layer is the layer located just below the tread and allows for high speed travel. This caiman consists of a single strong nylon cord embedded in the rubber. This cord spirals from one side to the other around the circumference of the tire without overlapping.

Strong steel cords in the belt layer provide rigidity to this tire, and this layer increases the directional stability of the tire, reduces rolling resistance and increases the mileage of your tire.

Tyre component testing is typically performed at ambient and typical environmental temperatures ranging from minus 70 to plus 250 degrees. These tests include:

Tensile and tear growth testing on elastomers with various sample shapes

Hardness, rebound and wear tests on elastomers

Abrasion tests on steel and textile cords made of elastomer bearings

Tensile tests on steel and textile cords Automatic sample feeding due to large sample quantities during the development of new compounds

Determination of viscoelastic properties

• Testing of rims: In the automotive sector, rims are made of steel, light metal or composite materials and their tires. Tires are complex composite bodies made of materials with various physical properties. As the link between the road and the vehicle, they transmit all forces and torques. Various test systems are used to determine the quasi-static and dynamic properties of rims and tires. This ranges from standard tests on rubber, textiles and spokes to tests on the entire rim/tire system.
• Testing of tyres and rims: The hardness of car tyres is determined by measuring the force ratios under vertical and horizontal loads as well as variable tyre pressure. A 50 kN testing machine is used, with a horizontal linear unit and a multi-component force measuring platform on the sub-base crosshead.
• Testing axial deformations of the rim flange: To determine the hardness properties, compression tests are performed on the rim flange with a special pressure spindle. For this purpose, a floor-standing testing machine with a forward-projecting, height-adjustable T-slot crosshead is used. In this way, the rims can be positioned and fixed at an ergonomically comfortable height in the test area. The load cell ensures that the axial force is measured precisely, even when lateral forces occur due to the geometric shape of the rim. Thanks to its special construction and layout, the load cell can be placed in the upper and lower test areas of the machine for measurements.
• Determination of full surface deformations in a lightweight rim: Axial or radial axle load is applied variably via an electromechanical actuator and the deformation behavior is recorded via an optical 3D deformation measurement system. The strain results provide information about possible weak points in the component.
• Hardness testing on flanges: Hardness tests for steel and aluminium wheels are primarily carried out according to the Brinell method HBW 2.5 or using Rockwell tests (e.g. HRB) for production control purposes and also to provide strength characteristic values. In addition, loads up to 250 kg can be carried out using closed-loop controlled technology for all classical hardness testing methods (Brinell, Rockwell, Vickers, Knoop and ball indentation hardness) for metal and plastic applications.
• Testing disc brake pads: Disc brake pads are one of the most important parts of a wheel brake. To assess the quality of the pads, among other things, the change in pad thickness is determined by one-dimensional compression loading in the direction of the friction surface studs of the disc brake pad. To accomplish this task, the material testing machines used are equipped with a compression test kit with an integrated measuring system.

Among the numerous tests, measurements, analyses and evaluations carried out by our organization for businesses in various sectors, our organization also provides quality testing services for wheels, rims and tires with its trained and expert staff and advanced technological equipment.