#pdccutter

All the drilling bits available these days can be broadly categorized as rolling cutter bits and fixed cutter bits. Let us take a quick look at the various aspects of each of these types:

Rolling Cutter Drilling Bits

Rolling cutter bits, also known as roller cone drill bits or tri-cone bits, have three cones and each of these can be rotated individually when the drill string rotates the body of the bit. Roller bearings are fitted onto the cones at the time of assembly. This type of drilling bits can be used to drill all kinds of formations with a proper cutter, bearing, and nozzle.

Rolling cutter drill bits can be further classified as milled-tooth and tungsten carbide inserts depending upon how the teeth are manufactured. TCI drag bits generally have tungsten carbide inserts (teeth) that are pressed into the bit cones.

Depending upon the formation, the shape of the teeth fit to be suited is determined:

·         Soft formation: Long-extension, chisel shape inserts

·         Hard formation: Short-extension, rounded inserts

Fixed Cutter Drilling Bits

Fixed cutter bits, on the other hand, consist of cutting elements integrated with the bit bodies. These are designed to excavate holes by shearing formations rather than cutting or gouging them how rolling cutter bits work. These bits do not have moving parts such as cones or bearings and their components are built of bit bodies fabricated from steel or tungsten carbide alloy and fixed blades integrated with abrasion-resistant cutters. The cutters in the bits that are available on the market are PDC cutters and natural or synthetic diamond cutters.

The improvements in the fixed cutter bit technology over the years have enabled the PDC bits to drill almost any kind of formations, from soft to hard.