Ball screw drives or linear motors? Or a four-axis versus a five-axis machine tool? Those are the kinds of questions that are motivating machine tool buyers to depend on their machine tool vendors as system integrators, says Ron Quaile, vice president, proposal engineering and marketing with MAG Powertrain, a supplier of metal-cutting solutions for the automotive industry.
With today's fast emerging technologies the answers to such questions carry significant cost and performance implications. For example, by specifying five-axis, fewer machine tools may be required. And although linear motors have been predicted to overtake ball screw drives, will linear motors prove effective in your application? Will they have the necessary power?
Quaile emphasizes that changes in buying practices make it more important than ever that the answers come from the most qualified sources. The reason: Machine tool purchases have evolved into more typically being system investments, not purchases of individual machines.
Quaile offers the following scenarios as true examples of the growing commitment significance of the machine tool builders as systems integrator:
Ron Quaile
Scenario 1 "Customer had a new part that could be economically machined on a transfer machine. After reviewing which features were subject to product changes as the product matured or was put into different vehicles, a cost-effective solution was devised that utilizes transfer machines for features not subject to change and CNC machines for other features. That allowed the customer to phase in the CNC machines to suit the market volume ramp, drastically reduce the cost and time to introduce part variation and feature changes."
Scenario 2 "Customer had a new part that was traditionally machined on a transfer machine. After studying the part and specialized tooling, prototype tools and fixtures were developed for low- volume production of specialized operations such as cylinder boring and crank boring operations on a CNC machine. This allowed the customer to significantly reduce investment costs and produce the prototype/test parts on the actual production machine."
Scenario 3 "Customer wanted to produce a variety of different parts and eliminate time and quality problems associated with machine changeover and the need to run large batches of parts on an older transfer line. Engineers replaced the older transfer line system with a flexible machining cell using CNC machines and a pallet transport system that allows batch of one production without any changeover or machine downtime."
Scenario 4 "Customer wanted to machine compacted graphite iron components but didn't have the specialized machining know-how required. Engineers developed the cutting tools and prototype fixtures required to make the part while concurrently working with product designers to simplify difficult-to-machine part features. The end result was a highly flexible CNC system with automatic gantry load, batch of one capability and an absolute minimum number of specialized machines."