ASTM D3336 Test Method for Life of Lubricating Greases in Ball Bearings at Elevated Temperatures
9. Procedure
9.1 Rotate the bearing by hand for approximately 100 revolutions in each direction at a speed not exceeding 200 rpm. Start the drive motor and heater simultaneously and adjust the temperature controller to raise the bearing to test temperature within 1 1/2 h. After two hours of test operation at speed and control temperature, measure the temperature of the outer race of the test bearing. Adjust the controller such that the outer race of the test bearing is at test temperature for the grease. Record test hours (running time), control temperature, and outer-race temperature of the bearing at least every 24 h. Unless automatic controls are employed, a 72-h shutdown (without applied heat) over the weekend, shall be followed. For Navy Type spindles the oven door shall remain closed during periods of shutdown.
NOTE 5 - Once satisfactory thermal stability has been established with the test bearing, no further manual adjustment is normally necessary. However, minor adjustments may be made to accommodate changing conditions of voltage, ambient temperatures, etc.
9.2 Continue the test until failure or completion of a specified number of known running times.
