Reamer
Precision tool used for finishing previously drilled holes, ensuring dimensional tolerances (H6, H7, H8) and controlled surface finish.
A reamer (Portuguese: alargador; German: Reibahle; Italian: alesatore) is a tool dedicated to removing a small amount of stock from a pre-drilled hole, leaving it within precise dimensional and geometric tolerances. It does not replace the drill: it works in sequence after it.
How it works
The reamer removes from 0.1 to 0.5 mm per diameter in a single pass. Multiple edges distribute the load and stabilize the cut, generating holes with cylindricity in the range of a few micrometers.
Types
- Solid (monoblock): body and edges in carbide or HSS. Service life determined by the first edge to fail.
- Modular with interchangeable head: reusable body, replaceable insert (Hanna HR® family).
- Reformable brazed: brazed edges, body can be reground several times.
When to use a modular reamer
In high-volume production and when carbide consumption impacts the part cost, the modular reamer is the only architecture that combines H7 tolerance with substantial savings in tungsten and cobalt.
Perguntas frequentes
- What is the difference between an alargador and an escariador?
- They are synonyms in Brazil. Escariador is the traditional term; alargador is the modern technical usage. In English, both are reamer.
- Is a modular reamer worth it for small series?
- Above ~500 parts/year per diameter, the modular system pays for itself because you only replace the insert instead of the entire reamer.