what is this machine used for?
To remove material.
Broaching (metalworking)
Broaching is a machining process that uses a toothed tool, called a broach, to remove material. 
write a detail note to the broaching machines Broaching machines are relatively simple as they only have to move the broach in a linear motion at a predetermined speed and provide a means for handling the broach automatically.
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Broaching (metalworking) [SEP] Introduction
Broaching is a machining process that uses a toothed tool, called a broach, to remove material. There are two main types of broaching: "linear" and "rotary". In linear broaching, which is the more common process, the broach is run linearly against a surface of the workpiece to effect the cut. Linear broaches are used in a broaching machine, which is also sometimes shortened to "broach". In rotary broaching, the broach is rotated and pressed into the workpiece to cut an axisymmetric shape. A rotary broach is used in a lathe or screw machine. In both processes the cut is performed in one pass of the broach, which makes it very efficient.