Iv

Cummins by Dr. Malcolm Naylor using a Cameron Plint tester, will now be made. Figure 13 shows the results from Dr. Naylor's tests for a variety of material pairs in terms of ring wear coefficient as a function of temperature. The wear coefficient is defined as the volume of material removed per unit length of sliding distance per Newton of force imposed. Note that the conventional chrome plated gray iron combination on the lower left-hand corner of the graph gives values of about lO-^2 mm3/mm/N at temperatures below 200 C. Such temperatures would be considered normal for highly turbocharged engines. As the temperature increases, the conventional chrome plate, gray iron combination begins to deteriorate significantly, giving wear up to 10~10 mm3 /mm/N at 400°C. The results listed in Table II show good agreement between the Hohman-A9 and Cameron Plint (TE77) wear tests.

0 0

Post a comment