Study on an Effective Coolant Supply Method in the Side Plunge Grinding Process

Abstract

Grinding is widely used for finishing components with journal and thrust surfaces, such as crankshafts. Side-plunge grinding enables the simultaneous finishing of thrust and cylindrical surfaces in a single plunge. However, compared to cylindrical grinding, it involves a larger contact area between the grinding wheel and the workpiece, leading to increased heat generation. In particular, poor coolant penetration near internal corners can degrade surface quality, potentially causing stress concentrations and cracks. To enhance coolant effectiveness in side-plunge grinding, this study installs a high-pressure nozzle that supplies coolant from the side of the grinding wheel. The effectiveness of this setup is experimentally verified. Additionally, the distribution of coolant flow within the contact area between the grinding wheel and the workpiece is measured to determine the optimal nozzle position for efficient coolant delivery. The nozzle’s performance is evaluated by measuring the workpiece surface temperature using a wire/workpiece thermocouple, the amount of coolant discharged from the grinding wheel, and the residual stress distribution. The results show that coolant penetrates the grinding wheel and effectively reaches the grinding zone, enhancing the cooling effect. This study clarifies the relationship between effective coolant supply and the position of the side nozzle. Considering physical constraints, such as potential interference during grinding, the optimal nozzle location is as close as possible to both the edge of the grinding wheel and the workpiece. This positioning ensures maximum coolant delivery, reduces grinding temperature, and helps suppress drastic variations in residual stress.