An Alternate Approach: Utilizing New PDC Technology for Drilling Deep LNG WellsDelivers Significant Savings for Major Operator in Oman

摘要

A major operator has been drilling deep liquefied natural gas(LNG) wells for several years in central Oman. These wellsare typically drilled vertically, featuring a complex geologicalsequence, that provides a significant challenge to bitperformance.Historically these wells have been drilled in 90 days withTungsten Carbide Insert (TCI) bits on packed rotaryassemblies down to the 9 5/8" casing shoe and Impregnatedbits on turbine assemblies with occasional TCI runs in the 83/8" section.A detailed study of the LNG wells focused on drillingperformance in each of the three hole sizes in a typical wellprofile. The findings suggested that the introduction of newPDC technology was viable over much of the intervals andthat significant savings in terms of time and cost could beachieved.This paper reviews the findings of the study subsequentrecommendations and the application of advanced PDCtechnology and stable PDC bit designs. The resultingimproved performance is demonstrated by examples shownfrom two separate fields in central Oman where significantsavings were achieved in terms of both rig time and cost permeter.The collaboration between the Operator, rig contractor, bitvendor and other service companies was necessary to providethe platform for a successful operation.