Control and planning

The data and parameters that must be evaluated at the time of writing a sequence of operations (road map) to be able to make a piece are the identification of machines, tools, tooling, selection of parameters of machining, operations, etc. The sequence is usually obtained according to specific objectives, such as minimizing production time and/or cost.

To deal with this information, the task of planning process is computer-aided by the CAPP systems. Different authors acknowledge that planning process contains a wealth of important manufacturing [1] data, not clear initially.

In industrial processes, costs of production and their minimization are a vital aspect in the production process. At first glance it seems clear that boot more material of the piece, in less time, would lead to lower costs of production, but not it is so because, for example, the wear of the tool.

The purpose of the article is the present automating the calculation of the cost and time of manufacture of the highest number of operations of machining in the most common chip removal processes.

To find times and final costs, it is necessary to study the parameters involved and the possible variations that can occur depending on the type of operation performed on a specific machine, in this study: lathe, milling machine, and drill. To do this, it is necessary to use a set of formulas that deal with tools, time of manufacture, the life of the tool, and the cost of the tooling. Has been used mainly the Taylor formula for the calculation of the life of the tool, although they have also studied and assessed, among other things, Kronenberg and Waxen formulas for the calculation of the life of the tool; and that of Bartolucci for the calculation of the hourly rate.

His study has allowed to modify and adapt in each of the different machining processes that can be performed on different machines, and get more adjusted and improved to each particular formulas. These formulas are those that have been implemented in the computer application that performs, automatically, the calculations of time and total cost of the machining operations of the most important processes of the machines used in a workshop in which machining processes are made by chip startup.

It is a robust and flexible turn application given that relies on a database that allows controlled, among others, the variables involved in target calculations.

The automation of these calculations is important because it reduces the time that is required at the time of assessing different road maps, no longer in search of the optimum, but in the valuation of the feasible in a situation of below or overuse of the factory. As a result can be a software application in which a CAPP system can support.

"[1] Ulusoy, g. Uzsoy, R.""Computer-Aided Process Planning and Material Requirements Plannins: first steps towards Computer-Integrated Manufacturing" Computers in Industry 22 (2) 76, 1992