The design engineering and construction of extraordinary large metal forming presses demand exceptional methods. It is a challenge for the design engineer to design presses that can bend 300 mm thick plates and handle forces up to 72,000 t.

In the field of metal forming Siempelkamp has manufactured several of the largest presses. Europipe is operating a crimping press with a capacity of 11,000 t for the production of pipeline pipes with a wall thickness of 50 mm. For Dillinger Hüttenwerke the company has build a straightening press for heavy steel plates with a thickness of up to 300 mm. The largest pipe forming press with a capacity of 72,000 t was also made in Krefeld, Germany.

Siempelkamp also supplies presses for the complete process chain in the area of titanium forming: At UST Kamenogorsk a compacting press was installed and for Goldsky Titanium Industry an open-die forging press for titanium components. At Aubert & Duval, a closed-die forging press with a capacity of 40,000 t is forging airplane components made of titanium and nickel alloys.

The design engineering and construction of large presses require other methods than those used for repetition parts: Before a new machine, which was produced in serial production, is introduced to the market, the manufacturers will test prototypes and initial batches thoroughly. Many details are optimized in this way before serial production starts. For large presses this is completely different. In their performance class every machine is unique. Oftentimes a press represents the centerpiece of a factory. If it is not working, production comes to a standstill. This means that from the day it is put into operation the prototype has to work reliably, efficiently, and precisely day in and day out for many decades.

To ensure that the prototype meets all required specifications and functions faultlessly at first go, the designing of new presses at Siempelkamp is a repetitive process in which engineers of different fields take part. A continuous dialogue between design engineering, engineering, foundry and production departments as well as a close cooperation with the customer, makes sure that the optimal solution is found for each task.

Siempelkamp has the experience of more than 125 years in designing and building large presses. The engineers handle the large forces which occur during crimping, straightening and forging processes. For each new press they benefit from the background knowledge gained from previous comparable orders.

The development of a press, which has to accommodate enormous forces, makes special demands. On the one hand the components have to be sized adequately; on the other hand the weight has to be kept within a limit. With castings the designing engineer can achieve the goal of optimally tailoring the shape of a component to its future function. To increase the load capacity of different areas, the designer can specifically add more material in some places and can take it away from other areas that are less stressed in order to reduce the weight of the component. Changes in sections can be streamlined to lower stress concentrations.

For a typical project, the customer first defines the requirements: here, the press capacity and durability of the press take center stage. Then, Siempelkamp deals with the project in several predetermined phases and always with multidisciplinary teams which are in a constant exchange of ideas. As one of the first steps, the engineers examine the feasibility of different options and develop the macro-structure of the press. This is a creative process during which the different manufacturing processes such as welding and casting are put to the test. If the decision goes towards ‘casting’, the design engineers examine cast steel as well as cast iron with spheroidal graphite. The result is a 3D model which is presented to the customer. Together with the customer, the requirements are then defined in detail.

During engineering, the model is tested under simulated working conditions with static and dynamic stresses. The Siempelkamp engineers model statics and dynamics according to the finite element method. During this process multi-body contact systems are used to determine the interdependencies of the different components. Afterwards, the process kinematics, for example for movable stamps, is determined as well as the thermodynamics. In another process step, the model is evaluated in the forming simulation. If the result is not optimal the design is changed and newly tested. At the end of this process the structure of the press is defined and the forces, the power requirements, and the dimensions of the components are known.