Machining Economics:
Design and operation of a manufacturing system should be based on economic considerations. This is always desirable to carry out a machining operation at minimum possible cost however satisfying all requirements of the machined components. Sometimes under certain circumstances (war like situation), one might be more interested in highest probable production rate even at higher cost per component to meet the critical demands of certain commodities. Though, one might be interested in profit rate instead of minimum cost per component, or maximum production rate. All such difficulty has been learned by optimization techniques. Majority of these difficulties are dynamic in nature.
In real life, a component undergoes various kinds of operations like milling, drilling etc. However, in this unit, to understand the process, a simple case of single pass turning has been explained. Although more practical case is multipass turning. The process followed is simple one. Make up a model (or equation) for the given kind of problem, differentiate it with respect to feed rate or cutting speed, and then solve out it to evaluate optimum cutting parameters (feed or speed).
Objectives
After reading this unit, you should be able to
- differentiate among variable costs and fixed costs involved in a manufacturing operation,
- understand the machining situations in which a specific criterion should be
- employed,
- appraise optimum machining conditions for the given criterion, and
- Change the evaluated optimum machining conditions accounting for the many kinds of constraints applicable to the type of operation under consideration.