Heidelberg Foundry Amstetten simulates casting processes with MAGMASOFT®
The 1400 °C hot cast iron melt gushes through the gate into the mold. The movement of the flowing metal in the casting rigging and in the gradually filling mold for printing press cylinders and the subsequent solidification process are only chaotic and accidental, at first glance. The engineers of Amstetten Foundry, which forms part of Heidelberger Druckmaschinen AG, are familiar with every detail of the casting system. They ran through the entire process in advance with simulation software. This enables them to predict precisely what the quality and characteristics of the cast iron cylinder will be, when it leaves the mold and is finally integrated in a Heidelberg printing press.
The Amstetten factory is one of the most up-to-date and efficient foundries in all of Europe. It acts as a center of excellence for the manufacture of castings, such as printing press side panels or cylinders, for the entire Heidelberg Group, which has a yearly revenue of three billion euros (~$4.4 billion) and 15,000 employees. The parts are core elements of the sheet-fed offset presses that Heidelberger Druckmaschinen AG, as the market leader, provides to users in the print media industry worldwide. “For our customers, just like for ourselves, the decision for Heidelberg is always a decision for quality,” is how Jürgen Schimmel, Director of Pattern & Casting Engineering describes the company’s vision, which he implements on a daily basis together with the 450 employees involved in casting production. This is because the quality of the individual presses to a significant degree depends on the quality of the castings produced in Amstetten.
Amstetten’s staff does not just produce castings for the Heidelberg Group: 50 external companies order large and small castings in differing batch sizes from the Amstetten foundry. Free market competition does not just make economic sense; it also serves to ensure that all processes are focused on achieving the highest quality, according to Schimmel.
“We have a clearly defined goal: economical casting production with consistently high quality. We see casting as part of an overarching process, beginning in design and finishing in reliably functioning, competitive end products,” Jürgen Schimmel says when formulating the “mission” of the Amstetten foundry. This level of quality is achieved by continuous IT support over the entire production process – from design of the components and patterns to the stable computer controlled melting and pouring processes.
Casting simulation bridges the gap between design and production
The planning department Pattern and Casting Engineering bridges the gap between computer-aided product design and actual production using MAGMASOFT®, the leading software for simulating casting processes. In doing so, the engineers rely on a technology regarded in the industry as one of the most important innovations of the last 50 years. This is because casting process simulation opens up the possibility of taking a look inside the former “black box” of the mold, to understand and predict precisely what happens during pouring and solidification of the melt. As a result, the foundrymen are in a position to accurately characterize the casting and production process as well as predict the casting's properties before production has begun. What this means in practice is that the engineers are in a position to develop a casting with defined qualities at their computers. Correct production parameters for the casting process, with which the casting can be produced economically and reliably, can be developed with calculable quality. Before simulation technology became available, the individual development steps had to be taken “by hand” – from the part design to its realization as a casting by means of numerous, expensive test castings – and at the end there was still no guarantee that the process would indeed be reliable enough for the casting to be produced in the defined quality.
Save on costs, implement innovations
The foundry of Heidelberger Druckmaschinen AG makes use of simulation technology throughout the entire product and process development process, in order to save materials and costs in a highly price-sensitive market on the one hand, and to drive innovation and optimize component integration on the other.
For example, so-called return scrap is saved by “riserless” casting. Since the melt contracts when it cools, like any material, additional metal usually has to be introduced into the mold via the risers in order to avoid defects / porosity – so-called shrinkage cavities – in the casting. Appropriate design of the casting process reduces return scrap and material consumption. Before making the investment decision for MAGMASOFT®, the foundry had calculated that using simulation return scrap could be reduced by eight percent – which would lower annual material costs by a six-digit euro figure. Additional cost savings accrue from optimization over the entire process. Thanks to the calculated cooling times, it is safe to run production at the fastest possible rate.
For instance, it was possible to greatly reduce shrinkage cavities during the manufacture of a chain guide by reducing riser volumes and altering the gating system. This not only resulted in a significant quality improvement, but also led to a reduction of €15.80 (~$22.75) per part in manufacturing costs, primarily from a reduction of approximately 2.5 kg in return scrap. Given an annual production of approximately 300 pieces, this comes to cost savings of around €4,700 (~$6,768).
Thanks to solidification simulation, it was possible to reduce the number of risers from 5 to 2 together with a 69 kg reduction in return scrap during production of a gear wheel, which lowered manufacturing costs per piece by €31 (~$44.65).
Simulation pioneer as technological partner
As its technology partner for simulation, Heidelberg Foundry relies on a pioneer in this methodology in MAGMA Gießereitechnologie GmbH, Aachen. In the late 1980s, MAGMA transformed casting simulation from university research to practical application. Ever since, the resulting software solution, MAGMASOFT®, has set technical standards when it comes to simulating casting processes. It simulates mold filling, solidification and cooling during the casting process as well as mechanical properties, residual stresses and distortion of the castings created.
MAGMASOFT® consists of a basis package and a series of additional modules which cover all casting process production steps. They support the user starting from the design of the component, the selection of the melt treatment and casting layout, through pattern design and mold production to final heat treatment and finishing. The MAGMASOFT® application spectrum covers all cast materials, such as gray and ductile cast iron as used at the Heidelberg Foundry as well as aluminum and steel. Every casting process can be simulated with the software in order to design and assess the casting and tooling layouts, cycle times and casting quality.
Simulation software selection criteria
“User-friendly operation, short preparation time until start of calculations, realistic representation of results – those were the leading functional criteria when we chose MAGMASOFT®,” explains Hans Frieß, Director of Planning/Material Management. “And of course, another factor was the potential for future developments in the software.” But it was not just the software’s functionality and quality that were relevant to the decision. MAGMA itself as simulation pioneer was a factor. Hans Frieß puts it like this: “MAGMA established casting process simulation technology as a practical tool. The industry owes its trust in simulation primarily to MAGMA. The associated market and technological leadership and references were also persuasive when we were thinking about introducing a solution.”
Amortization in one year
In the meantime, cooperation in Amstetten with MAGMASOFT® and MAGMA has a track record of about eight years. The investment was amortized within just one year instead of two, as calculated prior to acquisition. The use of the simulation solution has resulted in faster component development, higher component quality and more economic production. The technology has also assisted the foundry in terms of innovation: using MAGMASOFT made it possible to begin manufacturing larger, heavier types of components.
The software also plays an important role in marketing and sales. When potential customers inquire about a particular casting, they are not only provided with a price, but also a pledge of reliable component quality and delivery times, based on simulation results. “Thanks to our use of MAGMASOFT®, we have actually acquired customers. When we made the investment decision this effect was one we had neither expected nor taken into account,” Hans Frieß is pleased to note. MAGMA now occupies a correspondingly prominent place in marketing as well: there are numerous casting simulation visualizations on the foundry’s website, shown as recognizable screenshots from the MAGMA software.
And something else has undergone further development on the basis of the simulation software: communication with the casting designers and the foundry floor. The designers quickly get reliable feedback on whether a new component design is "castable", while production gets reliable information on how to handle the casting process to achieve the best result. Conversely, based on the documented simulation results, both parties with their expertise can prepare creative solutions, which in turn can then be quickly and easily checked using simulation.
Simulation in the future – knowledge management and service orientation
“Using casting process simulation has now become indispensable for foundries,” Hans Frieß sums up. This was the only way for them to become service providers, taking on design and consultative activities and cooperating more closely with the companies using castings. Moreover, the software protects against know-how loss, since the knowledge is no longer just in the head of an expert but instead stored in a way that can be reused in MAGMASOFT®'s databases. Consequently, the partnership between foundry and software will intensify further in the time to come - and continue on the basis of a new software generation, which will be launched shortly.