IADC CLASSIFICATION OF DRILL BITS
Numerous types of drill bits are available, i.e. the
largest manufacturer makes 34 types and 33 sizes and
many more on request - Confusing.
Code: 5 2 2 R
1. Series
2. Type
3. Feature
4. Feature (2)
Classification of RCB
Sta
nd
ard
Ro
ller
Bea
rin
g
Ro
ller
Bea
rin
g
Air
Co
ole
d
Ro
ller
Bea
rin
g
Gau
ge
Pro
tect
ed
Sea
lled
Ro
ller
Bea
rin
g
Sea
lled
Ro
ller
Bea
rin
g
Gau
ge
Pro
tect
ion
Sea
led
Fri
ctio
n
Bea
rin
g
Sea
led
Fri
ctio
n B
eari
ng
Gau
ge
Pro
tect
ion
SE
RIE
S
FORMATIONS
TY
PE
S
1
Soft formations with low
compressive strenght and high
drillability
1
2
3
4
2Medium to med-hard formations
with high compressive strenght
1
2
3
4
3Hard semi-abrassive and abrassive
formations
1
2
3
4
4
Soft formations with low
compressive strenght and high
drillability
1
2
3
4
5Soft formations with low
compressive strenght
1
2
3
4
6Medium hard formations with high
compressive strenght
1
2
3
4
7Hard semi-abrasive and abrassive
formations
1
2
3
4
8Extremely hard and abrasive
formations
1
2
3
4
5 6M
ille
d-T
oo
th B
its
1 2
Dir
ecti
on
al
Oth
er
Inse
rt B
its
IADC BIT CLASSIFICATION FORM
FEATURES
7 8 93 4
CO DE FEATURE CO DE FEATURE
A Air application N
B O
C Center jet P
D Deviation control O
E Extended jets R Reinforced welds
F S Standard steel teeth
G Extra gauge/body protection T
H U
I V
J Jet deflection W
K X Chisel insert
L Y Conical insert
M Z Other insert
FEATURE (2)
Example
Code: 5 2 2 R
5 = code for "insert bits“
2 = code for "soft to medium formation“
2 = code for "roller bearing air cooled“
R = code for "reinforced welds"
Code: M 5 8 2
1. Cutter type and body material,
2. Cross-section profile,
3. Hydraulic design,
4. Cutter size and density
Classification of Drag Bits
First code designations are
D Natural diamond/matrix body
M Polycrystalline diamond cutters/matrix body
S Polycrystalline diamond cutters/steel body
T Thermally stable polycrystalline diamond cutters/matrix body
O Other
Second code designations are
1. long taper/deep cone
2. long taper/medium cone
3. long taper/shallow or no cone (parabolic)
4. medium taper/deep cone
5. medium taper/medium cone
6. medium taper/shallow or no cone(rounded)
7. short taper/deep cone (inverted)
8. short taper/medium cone
9. short taper/shallow or no cone (flat)
Third code designations are
1. bladed/changeable jets
2. bladed/fixed ports
3. bladed/open throat
4. ribbed/changeable jets
5. ribbed/fixed ports
6. ribbed/open throat
7. open face/changeable jets
8. open face/fixed ports
9. open face/open throat
10. alternative codes
1. radial flow
2. cross flow
3. other
Fourth code designations are
1. Cutter size: large, medium and small
2. Cutter density: light, medium and heavy
Example
Code: M 5 8 2
M code for “polycrystalline diamond cutters/matrix
body“
5 code for "medium taper/medium cone“
8 code for "fixed ports/open face“
2 code for "medium cutter size/light cutter
density”