Bit Details

Daily Operations > Drillstrings > Components Tab > Component Details Button

The fields in the Bit area of the Component Details dialog for a Bit describe the bit characteristics including Bit Size, Manufacturer, Serial Number and Approximate Weight.

IADC Code

Enter the IADC Code to identify the Bit type. The following identifies the IADC Code for Rock Bits and Fixed Cutter Bits:

IADC Rock Bit Classification Code - Rock Bit codes represent an application guideline. The first number designates the Series (mill tooth or insert bit) and contains valid values of 1 - 7. The second number designates the type (hardness) and contains valid values of 1 - 4. The third number designates the Features (gauge protection, bearings etc.) and contains valid values of 1 - 7. The fourth digit is not used for rock bits.
IADC Fixed Cutter Bit Classification Code - The intention of instituting a common coding for fixed-cutter drill bits is to assist the evaluation and comparison of various bits with regard to design, operating practices, and performance. It also facilitates bit selection. The classification is represented by a four-digit code:

Body Material Steel or Matrix.
Cutter Density for PDC bits, this digit ranges from 1 to 5. The lower the number is, the lighter set the bit.
Cutter Size - This digit represents the size of PDC cutter used. It can be 1, 2, or 3 in descending order of cutter diameter.
Profile - The final digit indicates the general body style and varies from 1 (flat profile) to 4 (long flanked turbine style).

Fixed cutter IADC codes are intended only to provide a means for characterizing the general physical appearance of fixed cutter drill bits. Unlike the IADC classification for rockbits, these codes do not represent an application guideline. Fixed cutter bits with like or similar codes may have significantly different performance capabilities.

IADC Dull Grade Area

The IADC Dull Grading System allows for the detailed recording of bit condition at the end of the bit run. This system of recording allows the rigsite supervisor or engineer to note the physical condition of a bit for future performance analysis and offset well performance comparisons.

IADC Dull Grade			Description of Field Contents
IODL
	I	Inner Rows	The amount of cutting structure wear on the inner rows of teeth. This is calculated using a linear scale.
	O	Outer Rows	The amount of cutting structure wear on the outer rows of teeth. This is calculated using a linear scale.
	D	Dull Characteristics	See list of codes for dull characteristics.
	L	Location	Record the location of the cutting structure's dull characteristics in this field using the location codes table as a guide.
BGOR
	B	Bearing Seals	The condition of the bearing seals. See the list of codes for bearing/seals. If a fixed cutter bit is being graded, select "X Fixed Cutter Bits".
	G	Gauge	The measure of the bit gauge is recorded here. Select "I In Gauge" if the bit is still in gauge. Otherwise, the amount the bit is under gauge is recorded to the nearest 1/16th of an inch. Enter only the numerator of the fraction in this field.
	O	Other Characteristics	Any other dull characteristics can be recorded here using the same codes as the D field above.
	R	Reason for Pulling Bit	See a list of codes for reasons pulled.

For more information on the Dull Grading System, see the IADC Dull Grading System topic.

TFA Field

The TFA (Total Flow Area) is an editable calculated field. By default, the field is calculated, but a user can override the calculation by editing the field directly.

If the user changes fields that this calculation depends on or selects the calculated field and clicks the Calculated Current Field button icon in the toolbar, the application re-calculates the TFA..

The TFA calculation is based on the nozzles entered or it may be entered by the user where no nozzles are used (e.g., core bits). The Total Flow Area can only be seen when a Bit is selected from the spreadsheet.

TFA, or total flow area, is calculated as follows:

Total Flow Area = π r 2 + π r 2 + π r 2 ...for each jet

*Remember that if some jets are not present, enter 25.4 mm, 32/32 nds, or 1 inch, depending on which units are being used; or set them equal to the size of the jet receptacle.