Calculate the capacity rating of an endless wire rope sling used in a 338 °C (640 °F)
atmosphere. The 13-mm (1/2-in) diameter sling's tag shows a basket hitch capacity rating of 4.9 ton. The hitch is used to lift a 1.22-m (4-ft) diameter load by a hook, which has a 8.9-cm (3.5-in) diameter saddle surface. The rope's manufacturer describes a temperature efficiency factor of 0.65 for use in an atmosphere between 300 °C (572 °F) and 400 °C (752 °F).

A. Determine the D/d ratio for the curved surfaces.
D/d =
D/d =
B. Determine the Curved Surface Efficiency Factors using the graph.
Curved Surface Efficiency Factor =
(%)
C. Calculate the rated load for the entire hitch.
Rated Load =
(ton)