New Test Method for Evaluating the scuffing load carrying capacity of lubricants
1. Scope
This test method covers a procedure for evaluating extreme pressure properties of lubricating fluids under high-frequency linear-oscillation motion using SRV-type friction and wear test machines in the geometry as per ASTM D8316/ DIN51834-4 (inclined roller on disk). In this method, the extreme pressure performance of gear oil and transmission oil is studied by using cylinder-on-disk geometry to simulate the Hertzian contact stresses in the process of gear transmission. The Hertzian contact stress load increase of FZG gear oil method (e.g. ASTM D5182 or ISO14635) of approximately in average of 153 MPa is converted to the test load steps in the SRV-type test.
This laboratory test method mimics FZG load stages as pre-screening test and provides a methodology for screening the load carrying capacity of gear oils. It aims to easy screen new alloys and coatings interacting with lubricants candidates prior bench test and field trials. It can be used to quickly determine extreme pressure properties of lubricating fluids at selected temperatures specified for FZG load stages until 14 (P0mean= 2,127 MPa) and higher up to a literally FZG load stage of 17 (P0mean= 2,586 MPa). Users of this test method should determine whether results correlate with field performance or other applications.