During the use of the Centerless Grinding Machine, do you need to pay special attention to the design of the coolant nozzle or the optimization of the circulation path to avoid local overheating?

During the use of the Centerless Grinding Machine, you need to pay special attention to the design of the coolant nozzle and the optimization of the circulation path, especially when the coolant pump power is low, and you need to make up for the lack of flow or pressure through refined design. Since the temperature of the contact area between the grinding wheel and the workpiece can rise sharply to hundreds of degrees Celsius during the grinding process, if the cooling is insufficient, it will cause the surface of the workpiece to burn, the grinding wheel abrasive grains to fall off faster, and the key parts of the machine tool to be thermally deformed, which will directly affect the processing accuracy and equipment life.
Fan-shaped nozzles are suitable for cooling wide workpieces or full-width grinding wheels, conical nozzles are more suitable for deep holes or local high-temperature areas, and multi-hole array nozzles balance the coverage and impact force by evenly distributing small-diameter nozzles.
The spray angle needs to match the direction of rotation of the grinding wheel and the direction of feed of the workpiece. The nozzle spacing should be set to 70%~80% of the spray width to avoid overlap or gaps. Wear-resistant ceramic or hardened stainless steel nozzles are recommended. Their hardness is higher than that of ordinary metals, which can resist the erosion of grinding chips in the coolant and extend the service life.
The Centerless Grinding Machine uses a short path to reduce resistance loss, a large pipe diameter (such as DN25 and above) to increase flow rate, and an arc elbow replaces a right-angle elbow to reduce turbulence. Independent cooling circuits are added to key locations such as the grinding wheel-workpiece contact area and the guide wheel bearing seat, and the diversion ratio is adjusted by a solenoid valve or a manual valve to achieve precise cooling. A magnetic separator is equipped to filter grinding chips, the coolant is replaced regularly (recommended every 300 hours), and a plate heat exchanger is added to control temperature fluctuations (within ±2°C).
In actual maintenance, the nozzle blockage should be checked weekly, the nozzle should be disassembled to clean metal debris, and the circulation pipeline should be flushed with a high-pressure water gun every quarter to prevent scale or sludge deposition. Use an infrared thermal imager to scan the grinding area. If the local temperature exceeds 80°C, the nozzle position needs to be adjusted or the injection pressure needs to be increased. Record the grinding wheel replacement cycle and compare the data before and after optimization. A case of a bearing company shows that through the transformation of double-row staggered nozzles + spiral guide plates, the grinding wheel life is increased from 800 pieces to 1120 pieces, and the coolant consumption is reduced by 15%.