Improved Integral Joint Casing Connections Can Reduce Well Costs

Martin Bethke Conoco Inc. Lafayette, La.
Bob Moe Oil Technology Services Inc. Houston
Steve Morey Amoco Production Co. Houston
Brian Schwind Mobil Exploration & Producing U.S. Inc. Dallas


Improvements in integral joint connections (IJC) for casing in the past decade have allowed operators to drill wells previously not feasible to drill for economic or technology reasons.
New integral joint connections can withstand greater loads, increasing their range of applications. The use of IJC casing can allow a slimmer well to be drilled, reducing total well costs.
Fig. 1 illustrates two deep well programs (for Latin America and the Gulf of Mexico) currently used by a major operator. Both of these well designs require multiple casing strings. With conventional coupled connections, both designs would require extremely large diameter surface boreholes to accommodate all of the required casing strings to reach total depth (TD) with a 7-in. hole.
IJC casing was run in the wells in Fig. 1, allowing the use of much smaller structural, conductor, and surface pipe and reducing drilling time and costs.
Fig. 2 shows two sample well plans used by another major operator for deepwater (5,000 ft) Gulf of Mexico wells. The design goal is to reach TD with a 7/8-in. cased hole. The primary design limitation is the outer diameter (OD) clearance through the wellhead equipment.
The programs use IJC extensively and have proven successful both economically and technically.

  • Publisher: Oil & Gas Journal