No Disruption Allowed

Fiat Powertrain upgraded the CNC systems of 20 key machine tools used on the crankshaft and cylinder block production lines of its engine manufacturing plant in Campo Largo, Brazil, in order to extend their life cycle and minimize future maintenance downtime. Each machine required a custom upgrade kit comprising a high performance CNC unit, servo drives and motors, specifically designed by NUM Corporation (Naperville, IL) to facilitate fast installation and to provide improved diagnostics and simplified spares handling.

Part of Fiat Chrysler group, Fiat Powertrain operates manufacturing plants at strategic locations around the world, including four in South America. Its Campo Largo plant on the outskirts of the Brazilian city of Curitiba specializes in the manufacture of 1.6 litre and 1.8 litre ‘E.torQ’ flexfuel engines for medium size cars, which can run on petrol or ethanol. Originally set up by Chrysler and purchased by Fiat in 2008, the plant is one of the most modern in South America and plays an important role in Fiat’s leadership of the Brazilian automotive market – a position it has held for the past 12 years. The Campo Largo plant currently produces about 230,000 engines a year.

The Campo Largo plant makes extensive use of multi-axis CNC transfer machines, machining centers and specialist machine tools throughout its manufacturing operations. These include a wide range of Cinetic-Landis crankshaft grinding machines, Heller machines for the external milling and grinding of crankshafts, and transfer machines produced by Comau – a Fiat subsidiary – for engine block machining. In total, the plant’s crankshaft and cylinder block production lines are equipped with 20 key CNC machines, involving more than 120 feed axes. Each of these machines was originally controlled by a NUM 1050 series CNC unit, with NUM MDLU1 servo drives and NUM BMH series servomotors.

As the CNC systems aged, Fiat Powertrain became increasingly concerned with the likelihood of increased downtime. Troubleshooting and sourcing spare parts, as well as performing general machine maintenance, was threatening to take too long and impact production throughput. Since mechanically the machines were perfectly serviceable, in 2012 the company took the strategic decision to extend the life cycle of the production lines by upgrading all 20 machines with modern CNC controllers, drives and motors.

After reviewing various CNC manufacturers’ products and services, Fiat Powertrain concluded that NUM offered the best upgrade solution for the specific needs of the plant because it is the CNC OEM for the current machines and was able to provide a faster-to-implement solution with the best benefit/cost ratio. As Tarcisio Cruz Filho, the technical support manager at the Campo Largo plant, explains, “The fact that we were upgrading machines used for everyday production imposed some very demanding conditions. We needed a CNC supplier with the expertise and resources to collaborate on the design and installation of systems here in Brazil, while the systems themselves had to provide exactly the same level of functionality as our existing CNC equipment. We were impressed by the commitment to the project shown by their management team in Switzerland and by the quality of technical support – including several on-site visits – provided by their U.S. office, especially given that the Brazilian market for this CNC series is not huge.”

A key requirement of the replacement CNC systems was that they needed to be engineered in such a manner that the upgrade could be accomplished as quickly as possible to minimize manufacturing disruption. Using video conferencing, technical teams from Fiat Powertrain and NUM quickly established that NUM’s Axium CNC platform provided the least invasive upgrade solution for the machines, by using the same robust architecture as the earlier generation 1050 series CNC to keep wiring and software modifications to a minimum.

As part of the CNC upgrade process, the servo drives on each machine were replaced by models from NUM’s latest NUMDrive C range; these are some of the most efficient and highest power density drives on the market, which further simplifies installation by obviating the need for complex rack cooling arrangements.

The upgrade program also called for the motors on all the feed axes of the machines to be replaced. Originally, these were fitted with NUM BMH series brushless servomotors, which are robust medium inertia designs that were popular with machine tool designers for diverse positioning applications. However, they have now been superseded by NUM’s BPH series motors, which provide enhanced performance and environmental protection. The new BPH motors have physically identical shaft ends, pilot diameters and flange squares as their earlier-generation counterparts – again, making replacement a simple task – and the orientation of their power and sensor connectors can be altered during installation to suit the machine configuration. NUM also provides short adapter cables so that the existing motor wiring does not need to be changed, which saves a significant amount of time.

Filho points out that speed of upgrade was vital to Fiat Powertrain’s production schedules. “We allowed for a maximum of four days out-of-service time for each CNC machine on our crankshaft and cylinder block production lines,” he said. “All of the machines on these lines have now been upgraded and in each case – even on complex machines with seven controlled axes plus spindles – it took less time than we allocated, which says much for the CNC design and planning. The machines’ diagnostics are now much better, allowing us to perform more efficient preventative maintenance, and our technicians are now familiar with the CNC systems, all of which will help reduce production downtime in the future.”

In fact, collaboration in knowledge transfer proved to be another valuable point of the partnership. As Claudio Rocha, the manufacturing engineering director for Fiat Powertrain’s Latin American operations, states, “The exchange of information and the training that NUM provided for our maintenance staff during the upgrade were important. We appreciate this open approach and the commitment demonstrated by the supplier in this program.”

According to Steven Schilling, the general manager of NUM in Naperville, “Our engineers have considerable experience with highly specialized CNC machines of this type used in the automotive industry – we have a history of servicing the ‘Big Three’ in Detroit, Canada and Mexico. In this case, Fiat was fully involved at each phase of the upgrade, working under our guidance. This has enabled Fiat’s control technicians at the Campo Largo plant to gain a high level of our system know-how, to help achieve the project’s overall goal of maximizing the production lines’ life cycle. This a prime example of our ability to provide customers with end-to-end service options, allowing Fiat to keep ‘one step ahead’ of the competition.”