Duplex Profiles for Conveyor Belt Systems in Mining
Sometimes the most useful thing a supplier can do is question a requirement that has never been examined. Mato GmbH, a leading specialist in conveyor belt systems, was using extruded and cold drawn profiles in 304 stainless steel, a route that would have taken four or five drawing passes to reproduce and would have carried the cost to match. Discussing the drawing with the customer showed that the rounded corners inherited from extrusion were not necessary for the application, which opened the door to a square edged section produced by laser fusion in duplex 2205, at a lower cost and with tighter tolerances.
Questioning a Geometry Inherited From the Process
In mining, every material is exposed to extremely difficult working conditions, with equipment expected to resist abrasion, chemicals and water at the same time. Mild steel is damaged quickly in this environment, so solutions are increasingly sought among stainless grades, and special profiles in a wide range of steel qualities are common across the mining and quarrying sector. The customer specialises in conveyor belt systems and was working with a section made by extrusion followed by cold drawing in 304 stainless steel. Reproducing that profile would have required four or five drawing passes, which is both complicated and expensive, so the conversation turned to the shape itself. The rounded corners in the drawing were not a functional requirement at all. They were a consequence of the extrusion die, and once that became clear the section could be redesigned with square edges and a different production route.
Lower Cost Without Giving Up Strength or Tolerance
Three conditions framed the change. The first was commercial, since the objective was to reduce cost by using a production technology other than hot extrusion, which only became an option once the rounded corners were confirmed as non-mandatory. The second was technical, because the finished product still had to meet the strength and tolerance specifications of the section it replaced, and a redesign that saves money while losing mechanical performance is not a saving at all for a component working inside a conveyor system. The third concerned verification, with thorough inspection needed to guarantee the accuracy and consistency of the profiles, since a new route has to prove itself bar after bar rather than on a first article. The technical question sits in the middle of these. Laser fusion builds the section from prepared components, so the properties of the finished profile depend on the starting material and on how the joint is controlled.
Application Context
Montanstahl proposed a profile that is first cold drawn and then laser welded, an option that only became available once the rounded corner was set aside, and that replaces several drawing passes with a single efficient sequence. Duplex 2205 stainless steel was selected for its superior mechanical properties, which allow the new section to match the behaviour of the cold drawn predecessor it replaces while lowering cost and holding tight tolerances. On top of that, a 100 per cent inspection of all bars guarantees consistent quality across the entire production, an approach built into Montanstahl quality management and particularly relevant when a proven component moves to a new route. Custom sections of this kind are produced as special profiles to customer drawings, and questions on redesigning an existing section for a different technology are answered in the technical Q&A.