標準號：IS 1448 Pt.108-1982
發布日期：1982/5/1 12:00:00
實施日期：1999/12/31 12:00:00
適用范圍：This method covers the laboratory determination of apparent viscosity of engine oils at — 18°C and at high shear rates. The results are related to engine-cranking characteristics of engine oils ( see Notes 1, 2 and 3 ).Note 1 — The CRC test oils used to establish this method cover the range from 600 to 8 400 cP ( mPa.s ) at — 18°C and 2 000 to 20 000 cP ( mPa.s ) at - 29°C. Precision data for this method are based only on the data at — 18°C.Note 2 — The detailed relations between the apparent viscosities determined by this method and engine-cranking performance as determined by the Coordinating Research Council ( CRC ) L-49 test are shown in Appendices I and II of Method ( ASTM ) D 2602-67 T. See also CRC Report No. 409 ( available from Coordina-ting Research Council, INC., 30 Rockefeller Plaza, New York, N. Y. 10020 ). It is important to be aware that the CRC L-49 test is much less standardized and precise than this method. Therefore, apparent viscosity values obtained by this method may not predict accurately the engine-cranking viscosities in individual engines, even though the correlation with average engine results is satisfactory.Note 3 — Since this method was developed solely for use in relation to engine cranking characteristics of engine oils, the apparent viscosity values obtained should not be used to predict other types of performance. For example, the method is not suitable to predict flow rates to rocker arm bearings, or other engine locations at low temperatures.