A broaching machine pushes or pulls a long toothed tool, the broach, through or along a part. Each tooth cuts a little deeper than the one before, so one stroke finishes a keyway, spline, square or hexagon hole or a flat surface. It is fast and accurate for repeat parts, though each shape needs its own broach.
Quick facts
- Main types
- Vertical pull-down, vertical push, horizontal pull, surface broaching
- Capacity
- Rated by pulling force (tonnes) and stroke length
- Typical forces
- About 2–50 tonnes
- Typical work
- Keyways, splines, polygons, serrations, flat faces
- Accuracy
- Shape and size set by the broach; very repeatable
- Drive
- Usually hydraulic
Main parts
- Hydraulic ram that pulls or pushes the broach
- Puller head that grips the broach's shank
- Work table or fixture that holds the part
- Guide bushes for keyway broaches
- Coolant system
- Broach handling and return mechanism
Broaching or slotting a keyway?
| Broaching | Slotting machine | |
|---|---|---|
| Time per keyway | Seconds | Minutes |
| Tooling cost | Broach per size | Simple single-point tool |
| Best for | Batches and standard sizes | One-off and odd sizes |
| Blind keyways | No (through only, unless special) | Yes |
Good to know
- Push broaching with a press and a set of keyway broaches suits small workshops
- Internal splines and polygons are made in one pass with the right broach
- Broaches are costly but last thousands of parts when sharpened correctly
- Hole sizes before broaching must be within the broach's starting range
Need work done on a Broaching machine?
Post your requirement free. Workshops that take your kind of work see it and get in touch. You only talk to the ones that fit.
Get startedRelated
Related job work
Questions
- What is broaching used for?
- Mainly keyways in pulley and gear bores, internal splines, square and hexagon holes, and some flat or shaped outside surfaces.
- What decides the broaching machine size?
- The pulling force the cut needs and the length of the broach. Longer, wider cuts in harder material need more tonnes and a longer stroke.
- Can a broach cut a blind keyway?
- Not normally. A broach must pass right through, so blind keyways are cut on a slotting or shaping machine or by CNC.
The figures on this page are typical values for guidance, written by Diemeco from standard engineering practice. They are not a specification: confirm grades and properties with the relevant standard or the supplier's mill test certificate, and tolerances with your workshop. Last checked 22 October 2026.