Head Office and Surface Coating DivisionSomta House, 290-294 Moses Mabhida (Edendale) Road, Pietermaritzburg, 3201Private Bag X401, Pietermaritzburg, 3200South Africa

Tel: Factory: +27 33 355 6600Fax: Factory: +27 33 394 0564Tel: Sales: +27 11 390 8700 (Local)Fax: Sales: +27 11 397 6720/1 (Local)Email: jhbsales@somta.co.za (Local)Tel: Sales: +27 33 355 6600 (Exports)Fax: Sales: +27 33 394 7509 (Exports)Email: exports@somta.co.za (Exports)

Technical Information:Email: tech@somta.co.zaToll Free Number: 0800 331 399

Gauteng Sales Office 43 Bisset Road, Hughes Ext. 7, Boksburg, 1459P.O.Box 14212, Witfield, 1467South Africa

Tel: +27 11 390 8700Fax: +27 11 397 6720/1Sharecall: 086 010 4367Email: jhbsales@somta.co.za

Manufacturers & Suppliers

of Drills, Reamers, End Mills,

Bore Cutters, Taps & Dies,

Toolbits, Solid Carbide Tooling,

Carbide Insert Tooling,

Custom Tools and

Surface Coatings

w w w . s o m t a . c o . z a M T S C H I P B R E A K E R D R I L L S

Reco

mm

en

ded

Sp

eed

, C

oo

lan

t an

d L

ip C

leara

nce A

ng

le

2S

teel -

Up to 6

20 N

/mm

(175 H

B)

22

Ste

el -

>620 N

/mm

(175 H

B),

< 9

10 N

/mm

(250 H

B)

22

Ste

el -

>910 N

/mm

(250 H

B),

<1220 N

/mm

(350 H

B)

2S

teel -

>1220 N

/mm

(350 H

B)

Ste

el -

Manganese

(Low

)

Ste

el -

Sta

inle

ss -

Fre

e C

uttin

g

6 -

8

>8 -

11

>11

- 1

4

>14 -

17.5

>17.5

- 2

0.5

>20.5

- 2

8.5

>28.5

- 3

8

>38

Ste

el -

Tough G

rades

Metr

es

per

Min

ute

Feet per

Min

ute

Solu

ble

Oil

or

Para

ffin

Dry

or

Solu

ble

Oil

Dry

or

Solu

ble

Oil

Solu

ble

Oil

Solu

ble

Oil

Dry

or

use a

ir

Solu

ble

Oil

Dry

or

use a

ir

Solu

ble

Oil

Solu

ble

Oil

Solu

ble

Oil

or

Para

ffin

Solu

ble

Oil

or

Sulp

hurised O

il

Solu

ble

Oil

or

Sulp

hurised O

il

Solu

ble

Oil

or

Sulp

hurised O

il

Solu

ble

Oil

or

Sulp

hurised O

il

Solu

ble

Oil

or

Sulp

hurised O

il

Solu

ble

Oil

or

Sulp

hurised O

il

Sulp

hurised O

il

Solu

ble

Oil

or

Sulp

hurised O

il

Solu

ble

Oil

or

Sulp

hurised O

il

Po

int

An

gle

Lip

Cle

ara

nce A

ng

leC

oo

lan

tS

peed

61 -

92

46 -

76

61 -

92

30 -

61

22 -

30

30 -

46

22 -

24

15 -

22

8 -

11

30 -

61

Up to 1

22

12 -

15

30 -

61

24 -

33

14 -

22

9 -

14

5 -

8

5 -

6

15 -

18

6 -

15

200 -

300

150 -

250

200 -

300

100 -

200

70 -

100

100 -

150

70 -

80

50 -

70

25 -

35

100 -

200

Up to 4

00

40 -

50

100 -

200

80 -

110

45 -

70

30 -

45

15 -

25

15 -

20

50 -

60

20 -

50

12°

15°

15°

15°

15°

12°

- 15°

10°

- 12°

10°

- 12°

10°

- 12°

15°

12°

10°

- 12°

10°

- 12°

10°

- 12°

10°

12°

10°

10°

10°

- 12°

6°

- 12°

118°

118°

118°

118°

118°

90°

118°

118°

118°

100°

118°

125°

118°

130°

130°

125°

130°

130°

130°

130°

- 140°

Reco

mm

en

ded

Feed

Rate

s

Dri

ll D

iam

ete

r (m

m)

Metr

ic S

izes

Feed

per

Rev.

(m

m)

Imp

eri

al S

izes

Feed

is a

n im

port

ant a

spec

t in

succ

essf

ul p

erfo

rman

ce. W

hen

drill

ing

a ne

w m

ater

ial,

star

t at t

he lo

wer

end

of t

he re

com

men

ded

feed

and

incr

ease

unt

il op

timum

res

ults

are

obt

aine

d. O

ptim

um r

esul

ts a

re th

e lo

wes

tco

st in

pro

duci

ng th

e ho

le, t

ool l

ife b

eing

just

one

fact

or. E

mph

asis

sho

uld

be p

lace

d on

pro

duct

ion

rate

, with

tool

life

con

side

red

a pa

rtia

l cos

t of p

rodu

ctio

n, r

athe

r th

an th

e en

d re

sult.

Dri

ll D

iam

ete

r (i

nch

es)

Feed

per

Rev.

(in

ch

es)

Alu

min

ium

& A

lum

iniu

m A

lloys

Bra

ss

Bra

ss -

Leaded

Bro

nze

Bro

nze

- H

igh T

ensi

le

Cast

Iro

n -

Soft

Cast

Iro

n -

Malle

able

Cast

Iro

n -

Hard

Cast

Iro

n -

Chill

ed

Copper

Magnesi

um

Monel

Ste

el -

Pla

te, B

ar, C

ast

, F

org

ed F

ree C

uttin

g M

ild

0.1

0 -

0.2

5

0.1

5 -

0.3

0

0.2

0 -

0.3

5

0.2

5 -

0.4

0

0.3

0 -

0.4

5

0.3

0 -

0.5

0

0.3

5 -

0.7

5

0.4

0 -

0.9

0

1/4

" -

5/1

6"

>5/1

6"

- 7/1

6"

>7/1

6"

- 9/1

6"

>9/1

6"

- 11

/16"

>11

/16"

- 13/1

6"

>13/1

6"

- 1.1

/8"

>1.1

/8"

- 1.1

/2"

>1.1

/2"

0.0

04"

- 0.0

10"

0.0

06"

- 0.0

12"

0.0

08"

- 0.0

14"

0.0

10"

- 0.0

15"

0.0

12"

- 0.0

18"

0.0

12"

- 0.0

20"

0.0

14"

- 0.0

30"

0.0

16"

- 0.0

35"

Mate

rial to

be d

rilled

Chipbreaker Drills Chipbreaker DrillStyle Variations

Material Types

STANDARD DRILL IN ACTIONSTANDARD DRILL IN ACTIONSTANDARD DRILL IN ACTION

CHIPBREAKER DRILL IN ACTIONCHIPBREAKER DRILL IN ACTIONCHIPBREAKER DRILL IN ACTION

The Chipbreaker Concept

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.

M T S C H I P B R E A K E R D R I L L S

Chipbreaker Coolant Feed Drills

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 the flutes of the drill facilitating drilling to greater depths without

repeated withdrawal to clear swarf.

Coolant tubes or holes are located away from the drill web, thus not affecting

web strength. Both variants 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.

Drill chips

CHIPBREAKER

118° & 130° Standard Point 170° Brad Point

Point Styles

118° & 130°

Somta offers a range of Morse Taper Shank Chipbreaker Drills, with

variations in point angle, HSS grade and coolant feed options.

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.

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.

170°

Coolant Feed Styles

Normal Chipbreaker

Oil Tube Chipbreaker

This is the usual configuration of

the Chipbreaker Drill, which has

no coolant feed.

Coolant 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.

High Speed Steel Material Grades

HSS M2 ( )

Most chipbreaker drills are manufactured from standard

HSS material. HSS chipbreakers have a black oxide

steam tempered finish.

HSS-Co5 M35 ( )

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 to differentiate from the HSS steam

tempered finish.

OIL TUBE

OIL TUBE

Chipbreaker Product Codes & Features

The following table represents the standard range of

Morse Taper Shank Chipbreaker Drills stocked by Somta.

For ordering, specify the product code followed by a 4 digit code to represent the diameter.

For example a 30.5mm diameter oil tube M35 170° point chipbreaker would be

ordered as Product Code 2A73050.

2A1

2A2

2A6*

2A7

* Non Standard Product

118° standard

130° standard

130° standard

170° brad

Product Code Coolant Feed Option Material Point Style Flute Form

None

Oil Tube

Oil Tube

Oil Tube

HSS

HSS

HSS-Co5

HSS-Co5

Chipbreaker

Chipbreaker

Chipbreaker

Chipbreaker

Chipbreaker

NORMAL

ChipbreakerChipbreaker

OIL TUBEOIL HOLE

OIL FEED

OIL FEED

M T S C H I P B R E A K E R D R I L L S