Prediction of Cylinder Boring Surface Errors With and Without Cutting Fluids
 

Hong Li | MS | 1997

ABSTRACT:

Growing disposal costs and stricter environmental regulations are focussing manufacturers to pay attention to the various waste streams generated by metal cutting operations. Spent cutting fluid is one of the most significant waste stream elements in manufacturingfacilities today. Before use of cutting fluid is reduced or eliminated, the role of cutting fluids in machining must be established. In this study, the benefits of cutting fluids are examined with the primary focus placed on the use of coolants.

A set of preliminary experiments in a cylinder boring process was conducted in order to measure the cutting forces and temperature both with and without cutting fluids present. Temperature response was measured at five points in the cylinders. The influence of the cutting fluid on these experiments led to the investigation of the effect of cutting fluids on workpiece surface error, which results in poor engine performanceand excessive wear of cylinders and pistons. Surface error was mainly caused by the magnitude of cutting forces and the temperature distribution, which is created during the cutting process. The magnitude of the cutting forces and the temperature rise are dependent on boring-process variables, such as cutting conditions and tool geometry. Very little research, however, has been reported on the effects of the cutting fluids. This study seeks to address this defficiency.

Force models were developed based on the measured force data for prediction of the force system during cutting. The prediction of cutting forces is achieved through the development of a mechanistic model that accounts for the effects of cutting conditions and tool geometry variables on chip load, and the magnitude and orientation of cutting forces. The temperature field in the cylinder bore during machining is computed through the development of analytical solutions using the method of integral transforms. In this derivation, the tool-work interface is modeled as a one-dimensional moving plane heat source. The strength of the heat source and the heat convection coefficients were estimated based on the measured data by inverse methods.

Both the force and temperature models are used to calculate the surface error on workpieces with and without cutting fluid present. Finally, comparisons between measured and predicted forces, temperature distribution, and surface error are presented. These comparisons show good agreement.

If you have any comments or suggestions please e-mail jwsuther@mtu.edu.