Cutting tools - Broaching

Initially, broaching was simply an extension of mortising, involving the simple creation of internal keyways, but the process was subsequently improved and developed, enabling us to obtain all kinds of internal and external shapes, sometimes unattainable with other processes.

When it comes to medium and large production runs, broaching is always the most productive and therefore the most economical of all processes. This is why, in many production units, it has taken over many operations previously carried out by milling. This process enables roughing and finishing to be carried out in a single operation, precise shapes and dimensions to be obtained with excellent surface finishes, and perfect reproducibility even after a considerable number of broached parts.

To give an order of magnitude, spindles account for around 15% of the total cost of cutting tools used to machine an automotive engine/gearbox unit. In this figure, external broaches account for "55%, internal broaches for "35%, and the remaining "10% is accounted for by inserts and rings (the latter percentage is on the increase following the spread of new carbide broaching processes, i.e. with inserts).