IADC is  The International Association of Drilling Contractors.

Since 1940, the International Association of Drilling Contractors (IADC) has exclusively represented the worldwide oil and gas drilling industry.
IADC’s mission is to promote drilling and completion technology; improve industry health, safety, environmental and training practices; and champion sensible regulations and legislation which help safe and efficient drilling.


IADC code reference for Tricone Bits
IADC code reference for Tricone Bits

The International Association of Drilling Contractors came up with a system to describe any tricone bit through a simple 4 digit number.
This streamlines the process of ordering a new tricone bit for drillers everywhere.
By coming up with a simple 4 digit code to describe and categorize any tricone bit they eliminated any confusion that can arise when ordering.

This classification system dedicates the first 3 digits to the design and function of the tricone, with the final digit being an alphabetical code for any additional features of the bit.

Here is how to read an IADC Code properly:

IADC code explained
IADC code explained

The first digit represents the hardness of rock formation the drilling tool buttons are suited for
Every drill bit is designed for a certain type of rock formation, ranked according to hardness.
The tool is assigned a number between 1 and 8 indicating the type of rock the teeth or buttons of a drilling tool are designed for:

1, 2 and 3: Indicate a steel tooth. 1 is engineered for soft rock formations, 2 for medium formations, and 3 for hard formations.

4, 5, 6, 7, and 8: Indicates a tungsten carbide insert (TCI).
Within this category 4 is designated for the softer formations, with 8 representing the hardest formations

The second digit represents further rock formation information
Regardless of tooth type, the second digit takes into account all factors of the bit and ranks the rock formations the drilling tool is best suited for on a scale from 1 to 4. 1 represents soft formations going up to 4 representing the hardest formations.

The third digit represents the bearing type of the drilling tool.
For Example, Tricone bits use different bearings depending on the type of material to be drilled.

1, 2 and 3: are for roller bearings. 1 is for standard roller bearings, 2 is for air cooled bearings, and 3 is for open bearing with gauge protection.

4 and 5: sealed roller bearings. 4 is for standard sealed roller bearings, and 5 is for a sealed roller bearing with gauge protection.

6 and 7: sealed journal bearings. 6 is for a standard sealed journal bearing, and 7 is for a sealed journal bearing with gauge protection.

The fourth digit is a letter indicating the special properties of the drilling tool.
In addition to the buttons, intended rock formations, and bearings used, tricone bits can have numerous other special properties:

A – Air Application

B – Special Bearing

C – Center Jetted

D – Deviation Control

E – Extended Jets

G – Extra Gauge or Body protection

H – Horizontal/Steering

J – Jet Deflection

L – Lug Pads

M – Motor Application

S – Standard Steel Tooth

T – Two Cone

W – Enhanced Cutting Structure

X – Chisel Inserts


  1. Hi,
    I am a tricone products designer in a reputed MNC company.
    I would like to know is there any standard way of designing the cutting structure for tricone products as per IADC codes.
    Do we have any reference or standard to design a tricone bit for a particular rock formation and as per IADC codes?

  2. Hi
    This is Akrami and our company need to buying 20-50 Rock Bits PDC 17 1/2″ Please send me your offer and everything related to the business.
    Best Regards
    Director And management Of FSKCO

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