From the graph shown in the illustration, determine the size of the regulating ring required for the proper operation of the fuel oil centrifuge if the fuel oil specific gravity is 0.9 kg/dm3 at 68°F, and the separating temperature is 158°F. Illustration MO-0113

Correct Answer: Option D — 110 mm

Fuel oil centrifuge separating efficiency relies on correct gravity disk sizing. Using the specific gravity of 0.9 at 68°F and a separating temperature of 158°F on the manufacturer nomograph MO-0113 yields a required regulating ring size of 110 mm to maintain the proper oil/water interface.