Owing to JiaRun series products with the characteristics of good cooling, washing and deionization, the products are not only suitable for "HS-WEDM", but also for "MS-WEDM" and ordinary metal cutting. Whether the working liquid is suitable for "MS-WEDM" processing, the most intuitive phenomenon is that the hard and adhesive eroded particles can not adhere to the workpiece surface. Once the appearance of adhesion, the trim cuts with smaller energy parameters will be unstable, and the trim cuts can not be carried out. The most intuitive judgement in the machining is that if the workpiece can slide automatically or pick up easily after cutting, the working liquid is suitable for trim cuts of "MS-WEDM". The emulsion used in the past, thanks to the adhesive eroded particles produced in the inter-electrodes, can not be used in trim cuts and is not suitable for " MS-WEDM ".