Hydraulic damper test bench

The bench is designed for checking hydraulic dampers of the primary (axlebox) and secondary (central) suspension of passenger car bogies after repair, and for incoming inspection of new dampers. It determines the damping coefficient, the forces on the compression and rebound strokes, the symmetry of the diagram and the tightness of the unit, after which the damper is cleared for installation on the bogie or returned for repair.

The damper is mounted by its eyes between a fixed crosshead and a slider. The slider is driven by a crank mechanism from an electric motor through a frequency converter, producing reciprocating motion with adjustable amplitude and frequency. A strain-gauge load cell in the upper grip measures force, and a displacement sensor measures rod travel. The PLC plots the working diagram in real time, calculates the damping coefficient and compares it with the tolerance for the selected damper type.

The bench is built on a cast bed with vertical guideways, a height-adjustable crosshead and a polycarbonate protective screen. The stroke amplitude is changed by relocating the crank pin, and the frequency is set from the operator panel. The delivery includes interchangeable pins and adapter bushes for dampers with different eyes, as well as a heating chamber for bringing dampers to working temperature before the test.