The invention relates to a water-soluble 
cutting fluid, which comprises the following 
raw material components by weight: 3-5% of monoethanolamine, 5-8% of 
triethanolamine, 2-5% of 
boric acid, 3-5% ofsebacic acid, 2-5% of 
tribasic acid, 15-25% of 25# 
transformer oil, 4-6% of 
pentaerythritol ester, 5-12% of a T702 anionic surfactant, 5-8% of a 
nonionic surfactant, 0.1-0.8% of a 
copper corrosion inhibitor, 0.3-1.0% of an 
aluminum corrosion inhibitor, and the balance of water. According to the present invention, the water-soluble 
cutting fluid is the universal water-soluble anti-
hard water cutting fluid; the 
processing range of the water-soluble 
cutting fluid is wide, wherein the water-soluble 
cutting fluid can process 
cast iron, steel, stainless steel, 
copper alloys, aluminum alloys and a variety of 
metal materials; the water-soluble 
cutting fluid is generally suitable for 
soft water and 
hard water, can be used in all parts of the country, and has excellent hard-
water resistance, whereinthe water-soluble cutting fluid can 
resist the 
hard water in Shandong area (the hard water rang is 500-1300); and with the independently researched and developed anticorrosion 
system, the product does not produce deterioration and 
odor changing within the service life of 1 year, and is environment-friendly .