Field Trial Proves Upgrades to Solid Expandable Tubulars
Authors: Moore Melvin J. , Winters Warren J. , Zwald Edwin , Brisco David 
Published: October 2008

A 3,142-ft length of solid expandable openhole liner was installed successfully in a BP-operated well in November 2001. This established an industry record length and demonstrated two improvements:654 ft of liner were simultaneously expanded and pumped to the bottom of the well without the need to stop to make connections;a sliding sleeve valve permitted cement placement postexpansion prior to drill-out.

These improvements delivered significant time savings and offer reduced risk plus greater flexibility in the use of solid expandable liners.

This work was conducted as a technology field trial at an onshore location before trying it in the higher cost offshore environment. Key steps were taken to reduce the risks of this trial, including provisions to completely recover the expandable equipment from the well in the event of a problem. Also, risks unique to the relatively shallow depth of this installation were addressed and minimized.

Introduction

Expandable tubulars introduce promising solutions to some of the challenges encountered in engineering and economics of wells. A growing body of literature describes expandable tubulars mechanics, applications and field case histories.1-6 The first commercial installation of an expandable openhole liner was accomplished in November 1999. The work presented here was the 16th of 18 expandable liner installations undertaken by industry in year 2001. This paper reports fresh progress with upgrades to the knowledge and applicability of solid expandable tubulars.

The concept of solid tubular expansion in wells is fundamentally proven, but as with many new technologies the commercial uptake can be slowed by end-users' concerns about risk, reliability, versatility, etc. BP's offshore operations teams have been instrumental in voicing their expectations and requirements for expandable tubulars. This in turn has enabled our drilling technology group to prioritize the goals of an onshore expandables field trials program. We believe that field trials such as the one described here are an effective way to identify areas for improvement, demonstrate progress and ultimately gain confidence that leads to faster and more efficient utilization of the new technology.

Project Goals

Three technical advances and a fourth technical objective were sought in this field trial:

Expand more than 3,000 ft of liner.

Certain deepwater drilling environments require dependable 3,000+ ft capability in order for expandable liners to be of practical use. End-users tend to view solid expandable tubulars as an unwarranted risk if success in their well entails doing something not previously accomplished. The greatest lengths run prior to this test were in the range of 2,462 ft, 2,342 ft and 2,186 ft; hence the goal was to demonstrate deployment of more than 3,000 ft length, with deepwater drilling staff present to gain first-hand experience.

Expand via "scoping" technique.

The term scoping describes extruding the liner off the face of the expansion cone while literally pumping the expanding liner to the bottom of the wellbore.