Faster and more efficient — manufacturing cast parts with new processes
Knowhow Wilhelms GmbH combines 3D printing with arc welding. In this way they benefit from the advantages of the printing process and at the same time achieve a print rate of 600 cubic centimetres an hour.
3-D printing has already proved its worth in lightweight construction. Now the technology is showing its advantages in the manufacture of cast parts too. This is thanks to new processes being used by Knowhow Wilhelms GmbH, for which the company was awarded the Brandenburg Innovation Award Metal 2019.
In the manufacture and repair of cast parts there are always especially demanding tasks that push conventional processes to their limits. Companies manufacturing components with cooling channels or other cavities or repairing complex parts were until now reliant on manual welding. Smaller parts were usually milled from the whole piece; excess material had to then be removed afterwards.
Established 3D-printing processes already get around a part of this problem: Complex and small cast parts can be printed in a resource-saving way and when it comes to parts that need to be repaired 3D printers directly apply the missing metal. However, these advantages came up against a fundamental disadvantage: the print rate is just as low for conventional techniques as it is with selective laser melting (SLM), which greatly lengthens production time.
One of the innovations used by Knowhow Wilhelms addresses this basic problem: The company combines 3D printing with arc welding. In this way it benefits from the advantages of the printing process and at the same time achieves a print rate of 600 cubic centimetres an hour. This value is around three times higher than conventional, selective laser welding.
Complex parts whose manual manufacture is in some cases very difficult and thus expensive can be efficiently produced in this way. The new technology makes it easier for the Knowhow Wilhelms staff to repair cast parts more quickly. Robots apply the missing metal, while the employee’s tasks are focused on the finishing of the components.
The company from Königs Wusterhausen developed its plants for the 3D printing itself by reprogramming robots for the arc welding process.
Another innovation from Knowhow Wilhelms GmbH is the sand milling of large cast parts. The manufacture of individual large cast parts is generally time- and material-intensive. First, a physical model is created and cast. Then the metal is poured into the form. This process, from the creation of the model to the casting, takes up to five weeks. The model is not used again after its casting and has to disposed of. 3D metal printing cannot display its strengths here: The production process would take too long and would require additional manual finishing.
The new process of Knowhow Wilhelms GmbH for large cast parts reduces, however, not only the time needed but also the materials required: A digital, instead of physical, model of the cast part is created. A robot mills the model out of the sand and the metal is poured into the model. This means that the required time can be reduced by around four weeks and that material for creating the model can also be saved on.
The company from Königs Wusterhausen developed its plants for the 3D printing itself by reprogramming robots for the arc welding process.
Another innovation from Knowhow Wilhelms GmbH is the sand milling of large cast parts. The manufacture of individual large cast parts is generally time- and material-intensive. First, a physical model is created and cast. Then the metal is poured into the form. This process, from the creation of the model to the casting, takes up to five weeks. The model is not used again after its casting and has to disposed of. 3D metal printing cannot display its strengths here: The production process would take too long and would require additional manual finishing.
The new process of Knowhow Wilhelms GmbH for large cast parts reduces, however, not only the time needed but also the materials required: A digital, instead of physical, model of the cast part is created. A robot mills the model out of the sand and the metal is poured into the model. This means that the required time can be reduced by around four weeks and that material for creating the model can also be saved on.