... fit to high viscosity lubricant oil, freezing machine oil, hydraulic oil and gear oil etc.Guarantees & Documentation:TONGRUI Warrant ... required, please contact TONGRUI for additional charges. Working principe& flow chart:1, Working principleWhen the oil purification starts, firstly ... . Thirdly oil goes into intermediate filter. Fourthly oil flow into water separator, the water separator adopts a special ...