13 1/2" FSA515G, Rubber Sealed Roller Bearing , With Gage Protection , TCI Tricone Bit , Well Drilling Bit

RECOMMENDED DRILLING PARAMETERS FOR APPLICATION

The above chart represents commonly available sizes and types, we do produce other sizes and types of rock bits which do not appear on this list. Please contact us for more information.

Rock bit classifications

- IADC prepared a comparison chart, in 1972
- Each bit is design by three code system
- First code classifies the cutting structure, 1-3 for teeth soft, medium and hard, 5-8 for insert, soft medium hard semi abrasive, extremely hard and abrasive, 4 for future
- Soft rock require long, slim and widely spaced teeth
- Medium requires short and less widely teeth
-Hard requires very short and closely spaced teeth
- Code 2 relates to formation hardness with division from 1to 4 from softest to hardest
- Code 3 for mechanical features of the bit, sealed non-sealed etc
- Major bit companies are Hughes, Security, Reed, and Smith
- Each company give there tables with IADC specifications

Application of Teeth and Tungsten Carbide Insert on Roller Cone Bit
- Length and geometry relate the rock strength
- Size of the cone and bearing structure affect the teeth
- Teeth design criteria are:
Spacing and interfitting of teeth governed by tooth strength, depth and included angle
Shape and length, dictated by formation characteristics
Types of teeth, milled or inserted
- Log slider and widely spaced teeth used for soft rock
- Long teeth allow results in breaking greater volume
- Wide spacing allows easy removal of drilled cuttings
- The included angle for soft rock from 39 to 42
- Medium hard would have a moderate number of teeth and 43 to 45 included angle
- Hard rocks need 45 to 50 included angle
- Milled teeth are faced with hardening metal to reduce wear
- Milled tooth bits are suitable for soft formation
- Insert are used for hard formation
- There are several types of insert to suit the hardness
- Chisel-shaped for soft rock
- Round or spherical for medium and hard rocks