IADC 617 / 637 Series TCI Tricone Bits

IADC Classification: IADC 617 / IADC 637
Cutter Type: Tungsten Carbide Inserts (TCI)
Featured Sizes: 8-1/2", 8-3/4", 12-1/4", 17-1/2" (Full range from 5-7/8" to 17-1/2" available)
Thread Connection: Standard API Regular Pin
Bearing Structure: Sealed Roller Bearing (617) / Sealed Journal Bearing (637)
Formation Suitability: Medium-Hard to Hard Formations (e.g., hard limestone, dolomite, abrasive sandstone)

IADC 617 / 637 Series TCI Tricone Bits: Built for Tough, High-Strength Hard Rock Formations

As formations transition from soft sedimentary layers to abrasive, high-strength strata, drill bits require a much tougher cutting design. Bloom Machinery’s IADC 617 and IADC 637 TCI Tricone Bits are engineered specifically to conquer medium-hard to hard geological profiles, such as dense limestones, dolomite, hard sandstones, and chert-bearing formations.

Utilizing shorter, more closely spaced tungsten carbide inserts (mainly conical and spherical shapes), these bits concentrate weight-on-bit directly onto the rock face, crushing high-compressive strata with minimum insert breakage. The IADC 617 configuration uses precision-engineered sealed roller bearings, offering maximum economy for open-pit mining blast holes and water well drilling in stable rock. The IADC 637 variant is packed with sliding sealed journal bearings and extra tungsten carbide gauge protection inserts, delivering the necessary bearing life and gauge preservation required for deep oil & gas runs and highly abrasive geothermal wells.

Bit Size (Inch)	Bit Size (mm)	Available IADC	API Standard Pin Connection	Configuration & Gauge Feature
5-7/8"	149.2 mm	IADC 617 / 637	3-1/2" API Regular	High-density insert placement for rigid directional control in slimholes.
8-1/2" ★	215.9 mm	IADC 617 / 637	4-1/2" API Regular	Industry-standard size; reinforced inner-row inserts for maximum bottom-hole coverage.
8-3/4"	222.2 mm	IADC 617 / 637	4-1/2" API Regular	Mining and deep exploration favorite; exceptional shirtail and seal protection.
12-1/4"★	311.1 mm	IADC 617 / 637	6-5/8" API Regular	Intermediate hole master; maximized cutting structures for heavy drilling rigs.
14-3/4"	374.6 mm	IADC 617 / 637	7-5/8" API Regular	Designed for large diameter industrial wells and heavy infrastructure foundation shafts.
17-1/2"	444.5 mm	IADC 617 / 637	7-5/8" API Regular	Heavy-duty top-hole opening; optimized carbide rows to prevent drilling deviation.