Henan Hengtai Machinery Parts Co., Ltd. runs 28 two-shift CNC machining centers for cast iron brake discs and mechanical components. The previously used general emulsion featured insufficient lubrication and mediocre rust resistance, resulting in yellow oxidation on workpieces within 3–6 days of workshop turnover, with a 4.5% rework rate and massive monthly defective products. Poor lubrication also accelerated carbide tool wear and triggered frequent unplanned downtime. After upgrading to our S60 semi-synthetic cast iron cutting fluid, workpieces achieve stable 7-day rust-free storage, reducing the rust-related rejection rate to below 1.2%. The service life of carbide inserts increased from 800 to 1,450 pieces, lowering overall tool consumption costs by 42%. The service cycle of the cutting fluid was extended from 3 months to 6 months, improving equipment operation stability, raising single-line daily output by 8%, and effectively reducing daily maintenance and consumable costs.
