A Laboratory Method for Predicting the Permanent Viscosity Loss of Polymeric Crankcase Oils in Field Service
680069
02/01/1968
- Event
- Content
- A mechanical shearing test has been developed to evaluate the permanent viscosity loss of multigrade crankcase oils in field service. The test shows two advantages over a sonic shear test used previously. It causes polymer breakdown directionally the same as engines in the field, higher with higher viscosity oils; and test severity does not depend on the polymer type used. The new procedure provides a reliable laboratory technique for designing the used oil viscometric properties of multigrade formulations. Results from a 4 hr test predict the used oil viscosity with and without crankcase dilution, and also the extent of polymer breakdown in field service.
- Pages
- 12
- Citation
- Pearce, A., "A Laboratory Method for Predicting the Permanent Viscosity Loss of Polymeric Crankcase Oils in Field Service," SAE Technical Paper 680069, 1968, https://doi.org/10.4271/680069.