Lathes’ Machine Selection Base on Operational Sensitivity and Costing

Abstract

The need to estimate the cost of operating a machine tool for the purpose of pricing a job or billing a customer is of great importance. This would establish a good relationship between customers and operators. The cost depends on the sensitivity of the machine tool. In determining the sensitivity of lathes, parameters considered were the finishing time of operation in relation to the machining parameters which were feed, capacity and speed at a unit depth of cut. The component design parameters were metal volume removed, complexity and the skill level involved. Costing was done based on literature and the current prime cost of running and operating the machine shop. The developed numerical model has a coefficient of determination R2 of 0.962 specifying a high degree of agreement for experimental and theoretical data. The results showed that lathe machines with smaller capacity have lower operational sensitivity with more cost effectiveness where as higher capacity, numerical control and CNC lathe machines had higher sensitivity but less cost effective.