During the process of machining workpieces with machine tools, heat is generated, which reduces the machining accuracy and reliability of the machine tool, increases daily maintenance costs, and increases the operating costs of the machine tool. The AJ series immersion oil cooler combines years of experience in machine tool refrigeration, and is specifically designed to solve temperature control problems for machine tool spindle lubricating oil, hydraulic oil, cutting oil, grinding oil, and machining fluid based on the different characteristics of heating components during machine tool operation. Suitable for CNC lathes, CNC integrated machining centers, CNC grinders, CNC inner and outer diameter grinders, CNC milling machines, etc.