The High Temperature Wheel Bearing Grease Tester provides a comprehensive evaluation of lubricating grease performance under simulated automotive wheel bearing conditions.
Two key ASTM procedures are performed:
-
ASTM D3527 – Life Performance Test:
Grease is subjected to cyclic operation under high load, speed, and temperature until deterioration causes a defined torque increase in the drive motor. The total hours to failure represent the grease life performance.
-
ASTM D4290 – Accelerated Leakage Tendencies Test:
Similar test conditions are maintained for 20 hours to measure grease and oil leakage, followed by inspection for gum and varnish deposits.
The apparatus consists of a modified automotive front wheel hub-spindle-bearing assembly housed in a thermostatically controlled oven. The system integrates a 1/4 hp variable-speed drive motor, balanced 1/20 hp circulation fan, and microprocessor-controlled heating system to ensure uniform temperature up to 177°C (350°F).
A digital control cabinet continuously monitors and displays motor torque, rpm, chamber and spindle temperature, cycle timing, and elapsed test hours. When grease failure occurs (motor torque exceeding the calibrated limit), the test automatically terminates and records the total on-cycle duration.
A built-in 30-second surge delay circuit prevents false test terminations from startup torque spikes. The insulated oven includes sliding access doors and a swing-out drive motor platform for easy spindle access and maintenance. The hub-spindle assembly, machined to 1971 Chevy II dimensions, includes bearing thrust load controls, thermocouples, and an anodized aluminum grease collector for reliable, repeatable results.
