PCD BITS IN THE OUTBACK

Abstract

SANTOS Ltd, as drilling operator in the Cooper Basin of South Australia, has experimented with polycrystalline diamond (PCD) drilling bits in a variety of medium-cost drilling programs. PCD bits were originally designed for use in high rotary speed, low weight on bit, shale drilling environments. The operator has succeeded in reducing drilling costs by 32 per cent in some low rotary speed, high weight on bit, sandstone drilling sections. This was achieved without significant alterations to the existing drilling program.

The test runs of PCD bits also established optimum lithologies, optimum drilling parameters and techniques for detecting bit failure for use in the Cooper Basin. Drilling fluid systems and wellbore deviation control techniques were not altered while utilizing PCD drilling bits.

SANTOS has also concluded preliminary testing of PCD core bits, and believes their economic application will expand in the future.