Koehler High Frequency Reciprocating Rig (HFRR)

The High Frequency Reciprocating Rig is a versatile computer controlled apparatus for evaluation of the coefficient of friction and wear properties of materials under dry and lubricated conditions. Reciprocation motion occurs between the fixed stationery counter surface material mounted on a small lubricant bath and reciprocating specimen (ball) frequency, displacement, normal load are selected according to test requirement. Frictional force and coefficient of friction are measured with an electric sensor and data will be acquired, compared and analyzed through Data Acquisition Software. The oscillating motion is generated by a voice coil actuator. Frequency and displacement are controlled with an electronic closed loop system. Displacement frequency can set and read through a PC with software. The specimen holder is mounted on a flexure which is stiff in the vertical (loading) direction, but offers limited resistance to horizontal force movement to the horizontal direction. The Electric Force Transducer converts mechanical quantities, such as force, directly to an electric charge and is proportional to the force acting on the quartz crystal in the sensor, which is specified in the PC. An accelerometer is mounted on the output shaft of an electro-dynamic shaker which measures the displacement accelerometer and utilizes the spring mass system for generating a force proportional to amplitude of the input accelerometer to the base of system.