Chipbreaker Drills

Standard drill in action

Standard drill in action

This outstanding development increases drill cutting efficiency by means of greatly improved chip control. A chipbreaker rib is positioned along the length of the flutes, which curls and breaks long chip forming material into small manageable chips for easier evacuation. There is no clogging of chips in the flutes, as small chips flow freely along the flutes. The chipbreaker drill thus cuts more freely than standard drills.

The small chips also permit coolant to flow more freely to the drill point, giving improved heat dissipation and drilling performance. As the chipbreaker rib extends down the entire flute length, the chipbreaker form and effect is retained even after conventional sharpening. The chipbreaker rib gives added rigidity, markedly increasing the number of holes per re-grind, even where chip control is not considered important.

Chipbreaker Coolant Feed Drills

Chipbreaker drill in action

Chipbreaker drill in action

The benefits of providing coolant internally directly to the drill cutting edge include higher cutting speeds (reduced times by up to 75%), higher feed rates, longer tool life (3 to 10 times), and less frequent resharpening. In addition, they provide a superior finish.

The coolant assists in clearing chips from the drill point and it’s pressure forces the swarf along with the flutes of the drill facilitating drilling to greater depths without repeated withdrawal to clear swarf.

Coolant tubes are located away from the drill web, thus not affecting web strength, and connect to all coolant systems.

Coolant can be provided by the normal coolant pump supplied with most machines using soluble oil. However, we recommend using a mist coolant at a pressure of 550 to 800 kPa (80 to 120psi). This method is clean and efficient, eliminating the problem of collecting, filtering and re-using the coolant.

Style Variations

Somta offers a range of Straight Shank and Morse Taper Shank Chipbreaker Drills, with variations in point angle, HSS grade, Finish and coolant feed options.

Point Styles

normal 118° & 130° Conical
The conventional chipbreaker drill point angle is 118° or 130°, which is suitable for the majority of high-performance applications. 130° is suitable for harder materials.

Multi-Facet Point 118° Multi-Facet
The 118° multi-Facet point angle requires less thrust than conical therefore generates less heat. It is self-centering and therefore ideal for NC Machining.

brad170° Brad
Where through-holes are being drilled and there is a requirement for high operational efficiency without the need for deburring on punch-through, we recommend the use of a 170° brad-point angle.


Coolant Feed Styles

Normal Chipbreaker Normal Chipbreaker
This is the usual configuration of the Chipbreaker Drill, which has no coolant feed.

Oil Tube Chipbreaker
Oil Tube ChipbreakerCoolant is fed through shank cross holes into oil tubes which are inserted into a groove which runs down the length of the flutes. Oil is fed from the tubes at the outer edge of the point diameter directly onto the workpiece, cooling the workpiece and stimulating small chip evacuation. Because the chipbreaker rib breaks up long stringy chips into small pieces there is no chance of chips snagging and removing the coolant tube.

HSS Material Grades & Finish

Most chipbreaker drills are manufactured from standard High Speed Steel material. HSS chipbreakers have a black oxide steam tempered finish.

We also offer HSS-Co5 to extend product life even further due to the superiority of HSS-Co5 over HSS. All HSS-Co5 chipbreakers are finished with Gold Oxide surface treatment or are TiAIN coated to differentiate from the HSS steam tempered finish.

pdfView the Chipbreaker Drills Leaflet

Straight Shank Oil Tube Chipbreaker Drills
5xD – HSS-Co5 – TiAIN Coated

Straight Shank Oil Tube Chipbreaker Drills
10xD – HSS-Co5 – TiAIN Coated

MTS Chipbreaker Drills
HSS – Blue Finish

MTS Oil Tube Chipbreaker Drills
Cross Hole Feed – HSS – Blue Finish

MTS Oil Tube Chipbreaker Drills
Cross Hole Feed – HSS-Co5 – Gold Oxide Finish

MTS Oil Tube Chipbreaker Drills
Cross Hole Feed – HSS-Co5 – TiAIN Coated