3. Outdoor spindles

3.1 Area of use

Initially used for simple straightening and notching operations, external broaches are now designed to execute a wide variety of shapes which, in a single pass, can involve a large number of elements grouped together on the same train. The non-exhaustive figure 12 shows just some of the shapes that can be broached, either individually or grouped together on the same part when more complex components are involved, such as connecting rods (bodies and caps), bearing cap clusters and steering racks, to name but a few examples from the automotive industry. From the 1970s onwards, these techniques were complemented by a new external broaching principle:...