APR-WUBS-WFT-001 Issue Date: January 2006
Revision 001
Introduction to underbalanced drilling
Introduction To Underbalanced Drilling
Prepared by:
Ref APR-WUBS-WFT-001
Steve Nas Asia Pacific Regional Engineering Manager Weatherford Underbalanced Systems 238a Tompson Road #16-01/04 Novena Square Tower A Singapore 307684 Tel +65 6511 3688 Email:
[email protected]
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APR-WUBS-WFT-001 Issue Date: January 2006
Revision 001
Introduction to underbalanced drilling
Table of Contents INTRODUCTION .................................................................................................................................. 5 OBJECTIVES .......................................................................................................................................... 5 PERFORMANCE DRILLING ..................................................................................................................... 6 MANAGED PRESSURE DRILLING ........................................................................................................... 7 WHAT IS UNDERBALANCED DRILLING? .................................................................................... 8 UNDERBALANCED RESERVOIR DRILLING ........................................................................................... 10 HISTORY OF UNDERBALANCED DRILLING............................................................................. 11 WHY DRILL UNDERBALANCED? ................................................................................................. 12 UNDERBALANCED VERSUS OVERBALANCED ...................................................................................... 14 DISADVANTAGES OF UNDERBALANCED DRILLING ............................................................................. 15 LIMITATIONS ...................................................................................................................................... 15 CLASSIFICATION SYSTEM FOR UNDERBALANCED DRILLING......................................... 16 HOW TO DRILL UNDERBALANCED? .......................................................................................... 18 DATA COLLECTION ............................................................................................................................ 19 Reservoir Data .............................................................................................................................. 19 Reservoir Screening Tool (RST).................................................................................................... 20 SURE Phase II .............................................................................................................................. 22 Reservoir Damage Assessment ..................................................................................................... 22 Drilling Data................................................................................................................................. 24 Analog Data .................................................................................................................................. 24 EVALUATION .............................................