摘要 |
PCT No. PCT/GB93/01719 Sec. 371 Date Apr. 13, 1994 Sec. 102(e) Date Apr. 13, 1994 PCT Filed Aug. 13, 1993 PCT Pub. No. WO94/04919 PCT Pub. Date Mar. 3, 1994.A method of testing for contaminating mineral oil in a sample of synthetic ester lubricating oil from mechanical vapor recompression type heat transfer equipment in a system which is to be retrofilled with hydrohalocarbon working fluid, comprises mixing a predetermined quantity of the synthetic ester lubricating oil with a predetermined quantity of a polar liquid or a mixture of polar liquids and determining whether the resulting mixture is clear or turbid, an optically clear mixture indicating non-saturation by the contaminating mineral oil and that the concentration of contaminating mineral oil in the synthetic ester lubricant is below the maximum tolerable concentration and that the system can therefore be safely retrofilled with the hydrohalocarbon working fluid; and an optically turbid mixture indicating saturation by the contaminating mineral oil and that the concentration of contaminating mineral oil is above the maximum tolerable concentration and that the system must therefore be reflushed with synthetic ester lubricant to further reduce the mineral oil contamination. |