Siemens PLM on YouTube Siemens PLM on Twitter Siemens PLM on LinkedIn
TDK-EPC optimizes production with Preactor APS
June 2013
EPCOS was founded in 1954 and currently is headquartered in Gravataí City, Brazil. With more than 20 thousand employees, the EPCOS group has Project centers for manufacturing and sales in Europe, Asia, North America and South America. EPCOS AG, the group business based in Munich, Germany, is the leading manufacturer of electronics components, modules and systems. In 2009 EPCOS AG merged with the division of electronics components of TDK Corporation, resulting in a rising a new company: TDK-EPC Corporation, headquartered in Tokyo, japan. EPCOS Brazil is the group operation in South and Central America.

EPCOS Brazil develops and manufactures plastic film capacitors and aluminum electrolytic capacitors, including processing aluminum foil and plastic film for consumers.

It currently has about 1,600 employees, producing approximately 1.7 billion components per year, which are supplied to nearly 250 clients worldwide. The annual revenue of the company is € 120 million, of which almost 70% of the components produced at this factory are intended for export to Europe, Asia, NAFTA (North American Free Trade Agreement), South America and Central America. The sector that uses the majority of products from EPCOS Brazil / TDK is the automobile sector, with a third of the products consumed, followed by industrial, lighting, appliances, and others.

Challenge
The Axial capacitors unit from TDK-EPC has a different products family which represents the largest share of the revenues from the Gravataí’s plant. Before the project began, the scheduling process at the Axial unit was dependent on the use of spreadsheets and only the work centers identified as bottleneck were considered, which were the windings/pre-assembly. The demand variation between the different families of capacitors is high, causing the loading of different types to vary considerably along with the demand.

Without the visibility to plan and schedule production, the due dates given to customers were set by a fixed lead time which often was much higher than the factory would provide, if a detailed schedule had been made to predict the throughput time of an order. Whenever possible, the capacity of the plant is evaluated to better meet deadlines and due dates required by their customers, but even so, were missing a tool that can consider all the constraints of the production system and provide greater visibility of the program in the long term to guide the production planning.

Analyzing the flow of factory production, it was confirmed that all product families go through the same process until the intermediate stage of reoxidation, where they are divided and directed to the Special Processes, depending on the product family which it be part of. The reoxidation process, which is composed of several greenhouses performing a thermal treatment on the materials, could not balance its production appropriately, since there was no information on how many greenhouses should be used for each production order to improve such balance. In addition, the Special Processes are cause for another challenge: production balancing of various special processes in order to prevent them being idle or even overloaded when it's very dependent on the fluctuation in the product mix (demand variation for each product family). At the same time, it was necessary to evaluate the impact caused by the balance of the reoxidation process on the schedule of the initial production lines, which depending on the programming sequence, could result in high levels of setup times and greatly unbalance the production as a whole.

Solution
The Preactor APS solution was deployed in a factory of Axial capacitors, which has different product families. Many of the raw materials of this unit are imported and require a high level of control, so was identified the need to use the version P400 of Preactor to develop the solution which allows the full control of the stock levels and arrivals of purchase orders.

In its initial resources, winding, pre-assembly and assembly, the compositional characteristics of the products and their sizes are essential to achieve good sequencing, bringing more than a dozen product attributes to be mapped and evaluated to create the schedule. In addition, machine operators as well as technicians who perform the setups of winders are considered as constraints in the production process, since during certain periods of the day can't be allocated on multiple machines simultaneously.

After the initial process, it follows with the reoxidation process. At this point, an entire production order is divided into different batches to be processed in one or more greenhouses. To apply the sequencing of Preactor to production, it was necessary to calculate the number of greenhouses needed for each order and then define the total processing time  of reoxidation, analyzing the difference in cycle times with its previous process and also respecting the constraints and quantities of greenhouses available for production. It was also necessary to consider a minimum time for cooling the material after reoxidation so that the material may be ready for further processing.

In the final process, extra parameters were included to consider criteria that routes registered in SAP were unable to measure, as some specific attributes such as capacitors plated with gold, for example, could not be produced in some machines. As the production route is not detailed by machines in SAP ERP, but by production centers, the registration of valid resources on Preactor solved this need, making the program compliant with the technical constraints of each machine individually for each specific product. In these work stations, the amount of available operators was also included in the solution as a restriction.

Some steps of the quality inspection, between reoxidation and final Special processes, need a finite schedule, but were not prone to be bottlenecks at any point. To facilitate the organization of these sectors and the rest of the factory schedule, a logic program pulled customized reports to these work stations, analyzing subsequent operations and guiding its work for the processes that produces for the Special processes a schedule just-in-time. So, programming is benefited in two ways, the first being is that the balancing of the stations Special processes is not affected by the programming of these inspections, since the amount of Special processes is much larger than the number of checkpoints and programming these could generate unbalance of Special Operations, causing idleness, increasing lead-times and delays. The second way is that the pulled programming of these stations generates greater flexibility for the internal organization of the industry, allowing operators to be allocated on different functions depending on the scenario sequencing in progress.

At the planning level, the ability of creating multiple orders query for simulation of delivery times in the long-term was introduced into the solution, so the team responsible for defining and maintaining the delivery dates with customers is replaced by the possibility of using Preactor to perform such activities with a view of the finite capacity of its plant.

Results
The implementation of Preactor at the Axial unit of TDK-EPC brought many benefits to the company. The arrival of the software allowed the factory schedule to be integrated with other areas, such as the sectors responsible for the production of components, which serves as a raw material for the Axial unit, Logistics, an area responsible for production planning and promise due dates to customers, and the productive sectors of the Axial unit with each other, since previously only the winding and pre-assembly sectors were scheduled in detail.

The visibility of the schedule generated by Preactor enabled better planning of production capacity, allowing reductions in the number of shifts at some stations that were operational when it was found that the impact of changes caused the improved performance of delivery and the reducing cost of labor workforce. This same visibility revealed the need for reevaluation of performance indicators of the factory floor, since the Preactor schedule shows that the production of larger quantities of parts does not necessarily yield better final performance.

The flexibility of the solution has also enabled production targets and hence programming the factory was targeted differently depending on the variability of demand, which is common in an environment that produces most of its products for export and depends on the performance of the world economy to guide its strategies. For the future, with the potential of Preactor, EPCOS-TDK in Brazil foresees software deployment in other production units in Gravataí, as some factories that produce the raw materials are used in the center Axial.

Paula Antonov, Process Engineer and Project Manager says, "The product has very complex business needs. In addition to facilitating the activity of planning and programming, Preactor is able to assist in the strategic planning of the organization through visibility of the future situation.”