A practical field example proves a point - good ideas are rarely conceived in a vacuum.

Necessity truly is the mother of invention. This fact was brought home recently when I attended an excellent workshop titled Surface Technology Leadership Forum, sponsored by the Cameron Division of Cooper Cameron Corp. One of the speakers, Liew Anchaboh of Brunei Shell Petroleum Co. Sdn. Bhd., presented a case study of Shell's experience with conductor-sharing wellheads (CSW) offshore Brunei.
Spurred by the realities of brown field economics, Anchaboh and his colleagues developed, installed, tested and improved on a system whereby up to four wells could be drilled from a single platform slot. Not only does the practice extend field life, it does so very cost-effectively. In fact, CSW has been identified by Shell as a key enabling technology for development of mature fields.

To fully appreciate the value of their work, it is worthwhile to follow the development path. Back in 1998, it became obvious field life could be extended by drilling several horizontal development wells in Block 14 of the Champion Field. Alas, the 12-slot platform only had two unused slots. Siting another platform, even a small satellite, was out of the question economically, so the asset team started looking at ways to make use of the existing facility. Their solution wasn't too bad. Ultimately, they proved they could save US $1 million over a conventional approach and reduce installation time by 50%.

Initially, the team drilled three horizontal wells from two existing 30-in. conductors (leaving one shared well slot open for future development). They accomplished this by clever design using two sacrificial 133/8-in. conductors to fit neatly into each 30-in. slot. 121/4-in. holes were drilled and cased with 95/8-in. casing hung off in special eccentric hangers.

A key enabling technology was the ability to forge the wellhead housings onto the 95/8-in. casing stubs in situ. This technique, developed by Cameron and appropriately called Camforging, enabled subsequent work to proceed using standard unitized hangers and Christmas tree components, thus saving considerable time and money.

After proving the feasibility of the CSW technique, Brunei Shell set out to optimize it and extend the concept. In a joint workshop with their suppliers, they developed a set of requirements for future applications. Details can be found in SPE 68699, but essentially the team examined each element of the pilot program, improving or eliminating inefficient or costly steps.

The first application of the improved design involved drilling four deep extended reach wells from two new 36-in. conductors. Instead of using a sacrificial 133/8-in. conductor, the team figured out how to use a retrievable dummy casing that allowed drilling of a 16-in. deviated surface hole using a bi-center bit. Once the permanent casing was run and set, the adjacent dummy casing could be retrieved to enable drilling the second well. During this phase, designs were perfected for all common size conductors, and installation times were reduced by up to 55%.

Armed with an elegant solution using proven technology, the team set out to expand the applications to all appropriate Brunei Shell Petroleum properties. By late 2000, they had drilled 32 wells using CSW technology. In the process, cumulative savings of about $21.5 million had been realized, with an additional potential $5 million in savings projected for planned applications in the near future.

Although such praise would be well-deserved, this story is not intended to applaud Brunei Shell, or the Champion Field folks in particular, but to provide an example to illustrate the power of necessity in driving innovation. Using necessity as an incentive, and opening our eyes to look outside the box, we can often develop technology that not only solves our immediate problems, but also provides insight to solve them on a macro scale. The mother of game-changing technology is not always found in the research centers. Given the realistic constraints of time and budget, field-developed solutions are often elegant in their practicality and simplicity.

One might reasonably ask, "Why wasn't the CSW solution thought of in the first place when the Champion Field development was on the drawing board?" This makes my point - at that time the key element, necessity, was missing. No one envisaged drilling more than 12 wells from the platform, and the additional reserves targeted by the horizontal extensions were, at that time, undiscovered, or at least deemed non-commercial.

So every May when we pause to honor our mothers, those of us in this exciting, dynamic industry should say a prayer for the one that helps keeps the adventure alive - necessity.

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