Broaching machines

A broaching machine is a simple kinematic metal-removing machine tool, which operates either by pulling or pushing a tool called a broach. A broaching machine may comprise a single workstation or several. The station itself may be equipped with a single broach, as is generally the case for internal broaching, or with a whole set of broaches mounted on the same train or in a pot, for external broaching.

Originally, the first equipment used to perform a broaching-mandrelling operation consisted of a simple tool, driven into the workpiece by repeated hammer blows from the operator. The process was limited to making keyways.

In 1873, the term "broaching" appeared for the first time when Anson and Stephenson filed a patent for a proposed broaching machine.

In 1898, the first broaching machine was built in the United States by JN Lapointe. It was of horizontal design, with a screw-and-nut spindle-pulling mechanism.

In 1921, The Oilgear Co launched the first hydraulic-powered broaching machine. This was to be a decisive step, marking the beginning of a major expansion in broaching machines, first in the USA, then in Europe after the Second World War.

Broaching machines are grouped into two main families: one for internal broaching, the other for external broaching. Each of these categories includes horizontal and vertical machines.

With regard to the process itself, its field of application and the nature of the operations that can be carried out, the interested reader is referred to article B 7 087 "Cutting tools. Broaching" of the present treatise.

We would like to thank the Varinelli and Aumat companies (represented in France by Dismo) for the documentation provided.