Chip breakers for turning and bar peeling

The NRM has been designed for continuous and mass levels of production, offering consistent performance and high feeds. However, it is said to have excellent chip-breaking properties and can also be used for roughing of stainless steel even at lower feeds, without the risk of work hardening.

Its positive geometry with a wide T-land offers a broad depth of cut and promotes good chip evacuation in a wide number of applications. The chip breaker is available in grades T7325, T7335 and T9315.  

The NRM enhances Pramet’s range of turning chip breakers for stainless steel, including the NMR for medium to roughing operations, NM for medium turning and NF for finishing to medium turning. 

In a recent test, machining M group material DIN 1.4301, the NRM on the CNMG insert with T7335 grade, achieved a 60% longer tool life than a competitor equivalent.  

Meanwhile, Dormer Pramet has developed a new chip breaker for bar peeling of stainless steel, steel and super alloys. Suitable for roughing to finishing operations, the MM chip breaker has been designed with a wide, strong T-land to offer increased stability of the cutting edge. 

This gives the chip breaker good chip control with an even spread of the cutting forces, making it suitable for high feeds in heavy conditions. 

There are three cutting edge options: S01 is for hard materials, S02 for medium hardness and the S03 has a stabilised facet on the main cutting edge for soft materials.

The MM chip breaker is available for use with the LNGF inserts for roughing to finishing, RNGH inserts for roughing and WNGF inserts for roughing to finishing. It is suitable for use with grades T7325, T9315 and T6310.