ASTM D5182 Evaluating the Scuffing Load Capacity of Oils (FZG Visual Method)
10. Procedure
10.1 Prior to starting a test apply load stage 12 to the system for 2 to 3 min without running the motor (Table 1). This is done to ensure all clearances are in the correct working position. Remove all weights before proceeding to 10.2.
10.2 With the test gears mounted, load clutch locking pin in place, and load clutch bolts loose, apply load stage 1 (see Table 1) to the loading clutch. Tighten the bolts of the load clutch, (the load clutch bolts should be tightened in a star or crosswise pattern to a torque of 100 Nm) remove the weight assembly and lever arm, and remove the load clutch arresting bolt. Start the motor (1450 rpm) and turn on the heaters. Run for 15 min (21700 revolutions), then stop motor.
10.3 Insert the locking pin and loosen the load clutch bolts so that the load is removed from the shafts. Apply load stage 2 according to Table 1. Tighten the bolts of the load clutch, (the load clutch bolts should be tightened in a star or crosswise pattern to a torque of 100 Nm) remove the weights and lever arm, and remove the load clutch locking pin. Start the motor (1450 rpm) and turn on the heaters. After 15 min (21700 revolutions) stop the motor. Repeat this sequence for load stage 3.
10.4 Beginning with load stage 4, and all subsequent load stages, the procedure is the same as outlined in 10.2 except that the oil temperature must be between 90 and 93°C prior to starting the motor.
10.4.1 At the end of load stage 4 and each subsequent load stage, record the final temperature and inspect the pinion gear for damage without removing the gears from the gearbox. Record the type and amount of damage observed on the gear flank in accordance with the terminology described in Section 3 and from the examples shown in Fig. 4. The inspection is carried out without the aid of magnification. It is recommended that an inspection sheet such as that shown in Fig. 5 be used to record the damage observed after each load stage.
10.4.2 The failure criteria is reached when the summed total width of scuffing (adhesive wear) or scoring damage from all 16 teeth is estimated to equal or exceed one gear tooth width, that is, 20 mm. This is then reported as the failure load stage. Examples of acceptable and unacceptable distress levels are shown in Annex A3.
10.5 The test is continued until the failure load stage is reached. If the failure criteria has not been met after completing load stage 12, the test is terminated at that time.
