This work considered the finishing precision grinding process at a small ferrous metal roll manufacturer. A design of experiments methodology was used to evaluate the process and ascertain whether the degree of confidence gained from the process offers an acceptable level of risk in the conformance of end products to customer requirements. A thorough identification of the process variables and measurement considerations relevant to the process was carried out, before assessing and categorizing these variables using the grinding cycle as a 'black box' system. Coolant temperature, environment temperature, work speed, and traverse speed were all considered against measured size change, surface finish and circular run-out in a full factorial experimental design. The experiments were carried out on a manual cylindrical grinding machine retrofitted with digital encoders on the driven axes, with a chrome plated roll 300mm in diameter as the workpiece. Experiments were conducted over a period of 11 months during which the machine used was part of ongoing production environment. The results show that control of temperature, both of the coolant and of the environment in which the machine was operated, was the most important of the variables studied, but the skill of the machine operator remains dominant in the process overall. Copyright (c) 2017 by ASME
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