Precision profile rolling of metals

Conventional profile rolling usually can not be used for processing high-strength steel, especially when it comes to the mass production of well malleable materials. On the one hand, these materials require special machinery due to their high strength quality. On the other hand, the demands toward precision increases continuously. In this field of tension - the flow behavior on the one side and the precision on the other - in most cases a more cost intensive cutting technology is chosen instead of the better profile rolling method. Spindles and shafts are predestined examples of fine mechanics which easily can be produced with the profile rolling technology.

To get the profile-rolling technology ready for mass production and to make it cost efficient as well as precise, PENTACON and the market leader of profile rolling machines and our supplier BGH joined for a development consortium. The joint-venture started in 2012 and resulted in a mass production concept for profile-rolling of HSS S6-5-2.

Below is a list of geometries we are able to produce with profile rolling:

drive shafts in small engines

shafts in small engines

special profiles according to customer demands

augers in pumps

connection elements

postforming of sintered products

enhancement of the surface roughness of shafts as an alternative to grinding

Due to a functional development process the requirements on certain products grow which in the end results in higher production standards and in more sophisticated materials (e.g. automobile and medical technology, tool making). Especially parts that are exposed to higher thermal or mechanical conditions are usually exchanged with materials that meet the requirements but are also harder to form.

We process the following materials:

This technology can now be used wherever parts are under mechanical and thermal stress, e.g. pumps, gearboxes and engines.

Interlocking with 6 segments

As an example, we took an interlocking of segments made from a HSS S6-5-2 with Rm<850N/mm². With this a tolerance of ±0.05 at the outside diameter and a process capability of Cpk 7.45 for a serial production amount of parts could be validated. The ball measure at the tooth flanks with a tolerance of ±0.05 at a process capability of Cpk 4.53 speaks for a stable mass production.

Depending on the specific application, parts of the profile rolled parts can be injection over molded in a following production step. These parts of the geometry usually feature less thermal or mechanical stress. This method of partial metal substitution allows cost reductions aside from the reductions caused by the profile rolling.

Advantages

  • cost reduction through forming instead of machining
  • less material scrap
  • technology combination via plastic injection molding

Downstream processes

  • depending on the design and its geometry, the profile rolled parts might be grinded in a downstream process

Potential fields of application

Powertrain/ Diesel engines

Why not exchange the classical triangle or square shaped cut for guiding a nozzle needle with a helical gearing? For producing nozzle needles for injection fuel engines, usually a HSS-blank (e.g. S6-5-2) with various geometries is produced and grinded in multiple downstream steps. Here, an innovation process cuts in, to eliminate the cost intensive and critical grinding process in favor of a precision helical gearing. This method is a proven concept for mass production.

Shafts in small transmissions and electric engines

Spindles and shafts bearing elements for transmitting forces are ideal to combine technologies such as profile rolling and plastic injection molding. Here, we offer a vast range of materials that are close or similar to high strength materials. Starting with designing and optimizing your product, we offer service from a single source.