A method of measuring pumpability of oils used for power saw chain lubrication at low temperatures
1995
Skoupy, A. | Stastny, H. | Zach, J. (Mendelova Zemedelska a Lesnicka Univ., Brno (Czech Republic). Lesnicka a Drevarska Fakulta)
A methodology of testing pumpability of oils used for power saw chain lubrication at temperatures to -20 degrees C is proposed. The principle of the test is pumping of oil through throttle holes by in advance set vacuum at various temperatures. The limiting condition is a requirement to pump at least 5 ml of oil per 60 seconds. A total of 19 oils, two mineral oils among them, were tested according to the method proposed in this paper. The curve of the relationship of time needed for pumping 5 ml of oil and its temperature was fitted with hyperbolic functions with the best shape for all oils. Correlation indexes were mostly higher than 0.9. The curves of pumpability for the oils are largely different. Some oils are easy to pump almost by the point of thawing, others have the point of congelation approaching temperatures lower than -20 degrees C but they can be pumped by -5 degrees C only.
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