Spring Testing

Multi-Channel Spring Testing

Multi-channel measuring platforms allow the force vector of compression coil springs (used as a valve spring or in MacPherson struts) to be determined. Standard testing systems are equipped with a six- or nine-component force measuring platform for this. This enables the specific determination of the spring intersection points and the resulting force from the force components when loading the spring under compressive force. These characteristic values are important to evaluate the following quality attributes: friction, wear, and service life.

Testing Pneumatic Springs

Testing Pneumatic Springs at Various Temperatures

With this testing system, the visco-elastic properties of pneumatic springs and their fatigue properties are examined under various temperatures. A servo-hydraulic testing machine with hydrostatic cylinder bearing serves as the foundation. A special compression unit (mounted on a T-slotted plate) allows you to mount various pneumatic spring shapes and sizes. The fixture is also equipped with two measuring transducers for measuring the pneumatic spring diameter. The entire fixture can be inserted into a temperature chamber in a temperature range from -80 to +250 °C.

Testing of Multi-Axial Springs

Multi-axial loading of pneumatic springs to EN 13597

This testing system supports quality assurance and the development of pneumatic springs. It consists of a floor-standing testing machine with Fmax 250 kN. It is equipped with an additional horizontal, electromechanical drive with Fmax 50 kN and a force measuring platform with five load cells (3 vertical and 2 horizontal). The axial and horizontal stiffness characteristics of pneumatic springs are determined under vertical, horizontal or combined loading, and the following channels can be individually controlled:

Force and travel, vertical
Force and travel, horizontal
Air or liquid internal pressure

For easy insertion of the specimen, the system is equipped with a loading table that can be used to push the specimens into the testing machine.

Multi-Axial Testing of Struts

This testing system is equipped with three test axes to measure the damping characteristics of the hydraulic shock absorbers. The vertical force (wheel load) is applied by the testing machine axis. Horizontal forces and torsion moments that occur when maneuvering curves, approaching, and braking, etc. are generated through a horizontally affixed single testing actuator and a torsion drive. The test axes can be individually and independently controlled from one another. This way you can determine the characteristics (damping friction, viscosity) at different axial speeds with and without lateral forces and torque.

Quality assurance in suspension development at BMW

In the premium car segment, Bavarian automobile manufacturer BMW is synonymous with innovation and driving pleasure. In living up to this claim, BMW attaches great importance to comprehensive quality assurance right from the development stage of vehicle suspension, beginning with the testing of individual suspension components such as helical compression springs. Relevant parameters include spring characteristic curves, distribution of resulting forces and intersection points.