Hot Extruded Stainless Profiles for Elevator Sills
An elevator sill is walked on thousands of times a day and looked at every single time, so it has to combine wear resistance with an appearance that holds up under close inspection. A major lift manufacturer was producing these profiles by milling them from flat bar, a route that generates a large volume of chips and needs several passes before the section is finished. Montanstahl proposed hot extrusion instead, producing near net shape profiles in stainless steel 304 from the customer’s own design, cut to 244 cm and delivered with a surface ready for polishing.
Milling a Complex Section Out of Solid Bar
Elevator sills are under constant mechanical stress and have to satisfy demanding aesthetic and dimensional requirements at the same time, which is an unusual combination for a component that is essentially structural. A major lift manufacturer approached Montanstahl looking to improve the production process behind its systems, asking for tailor made stainless steel sill profiles with high wear resistance, durability and excellent surface quality. Until then the company had produced this type of profile in house by milling it from a flat bar, a method that removes a great deal of material as waste and requires several processing steps, both of which push cost upward. The geometry made things worse rather than better, because its complexity often left manufacturing inefficient, and that inefficiency multiplies at production volume. Components like this appear throughout the machinery and equipment sector, where a milled part is frequently the default simply because no one has revisited the starting point.
Several Geometries, One Tolerance Class and a Surface to Match
Four requirements shaped the production of the profile. The first was variety, since multiple geometries had to be supplied, each designed for strength and wear resistance, because a lift range covers different door widths and door types and each configuration has its own sill. The second was accuracy, with tight dimensional tolerances to be held on custom geometries that include narrow slots, grooves for the door guides and thin upstands, all of them dimensioned individually on the drawing. The third was that the profiles had to arrive cut to length, ready to enter the assembly line without further preparation. The fourth concerned appearance, because the surface finish had to be suitable for the polishing the customer performs, which means the section must leave production without scale, tool marks or defects that a polishing operation would only make more visible.
Application Context
Hot extrusion produces near net shape stainless steel profiles directly from the customer’s design, which changes the economics of the part rather than just its supplier. The process covers multiple geometries with strong mechanical properties and good wear resistance, and the profiles were extruded to tight tolerances, cut to 244 cm and delivered with a surface suitable for polishing, one of several surface finishes available. Because the material is formed rather than cut away, the grain structure runs continuously along the section instead of being interrupted at every machined face, and that continuity gives excellent fatigue resistance in a component under constant mechanical stress. The customer gained reduced machining, lower costs and shorter lead times while still meeting the technical and aesthetic requirements of the original design. Sections of this kind are developed as special profiles from customer drawings, and questions on geometry limits and finishing are answered in the technical Q&A.