This paper was prepared for presentation at the 1999 SPE Annual Technical Conference and Exhibition held in Houston, Texas, 3–6 October 1999.

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractA newly developed multilateral junction system utilizing formed metal technology led to the installation of the world's first Level 6 multilateral completion in the South Belridge Field near Bakersfield, California. This multilateral system provided a hydraulically sealed junction that, during installation, had an effective outside diameter less than the sum of the junction's two lateral casing legs. The junction was capable of running through standard casing and hole sizes as a result of this reduced diameter. Downhole, the junction was reformed using swaging technology. This multilateral system used conventional casing, cementing and drilling systems. In addition, no milling was required and therefore no debris was created.As a result, the overall process of creating the multilateral was simplified and associated risks minimized.In this paper, the authors will discuss this level 6 multilateral completion including an operational description of the junction system itself. The authors will outline how the system was installed and operated, including the difficulties encountered and how lessons learned from the first installation are being applied to improve performance and process in future applications. The authors will also explain how the service company and operators worked together to finance this multilateral system such that it could be applied in a low cost, low risk environment prior to application in very high cost, high risk, environments.