ASTM D4693 for low-temperature torque of grease-lubricated wheel bearings
ASTM D4693 standard test method for low-temperature torque of grease-lubricated wheel bearings
9. Bearing Preparation
9.1 New bearings must be conditioned prior to first use in this method. Install any wheel bearing grease in the bearings and run them at room temperature for 48 h at 1000 rpm under a thrust load of 110 N•m. The apparatus used in Test Method D3527 has been found suitable for conditioning the bearings. Alternatively, other means, such as a drill press, may be employed if the proper speed, load, and duration can be provided.
9.2 Remove excess grease from the bearings. Place the bearings in a beaker and cover with 1,1,1-trichloroethane (7.3). Place the beaker containing the bearings and solvent in the ultrasonic bath containing distilled water at a depth of about 60 mm. After cleaning for 5 to 10 min, transfer bearings to another solvent-containing beaker and repeat. Repeat as often as necessary (commonly, three times) to clean bearings; use shorter wash times with successive washes. Drain and air dry bearings.
