Dragbrotschning av invändiga profiler
High-precision cutting in metal is very complicated, a lot of parameters affect the result: what geometries to be manufactured, surface roughness and tolerances to be achieved, batch size etcetera. When pull-broaching internal parts this might be even more important, than in any other cutting operation. Everything is machined in one single stroke and the general technology is built in to the tool, therefore big investments must be made to change the process. Milling for an example: one piece at a time is machined away, and a lot of parameters can be changed easily.It is very high pressure on the cutting-edge when the broach is cutting. To achieve the specified product and to avoid unnecessary toolwear it is essential to use the right cuttingfluid and the right cuttingspeed for an example. An investigating interview has been made at Scania in Södertälje, to see how theory is related to practice. The result was not the expected. One reason might be that found literature in the subject was very old, and another might be that manufacturer of broaches work in secret and do not want to share their advantages so they can keep a market-leading position.