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Production

Autonomous tractoring (LWI), for subsea wells further increases became ‘business as usual’ and with it,

The ? rst version of a new costs and deployment times. further innovations helped to increase autonomous tractor unit for

For the well intervention industry, the applications, from logging operations well work, developed by Welltec arguably the last true innovation came to a full suite of mechanical services, with the introduction of the well inter- which includes milling, plug-setting, and BP, undertook its ? rst vention tractor in the mid-1990s, says sleeve manipulation, perforating, and commercial deployment

Callum Munro, senior well engineer, BP. well clean out activities.” “Tractors transformed horizontal well BP was aware of several projects, in January. Elaine Maslin interventions from large coiled tub- which had started investigating the idea found out more. ing operations to more nimble wireline of down-hole robots, or autonomous operations, using fewer personnel, less intervention units (AIU). Development ell intervention operations equipment, and crucially resulted in work in the US resulted in a caterpillar- continue to pose signi? cant less risk,” he says. “Tractor operations tracked prototype tool running in and

W risk, cost, access, and com- out of a US land well, proving the plexity challenges to operators, region- theory, Munro says. The project

Conveyance method ally and globally. was developed by IIC, and the cost comparison

However, the rewards from well inter- tool system was called micro rig. 9 vention activities through incremental oil Further development of this sys- 8.3 8 or gas rates can be signi? cant, especially tem however failed to materialize. when compared to rig based drilling and In 2009, BP and Welltec col- 7

AMBITION completion activities. laborated in a project to further 6

The spread of well intervention equip- develop Welltec’s patented Well 4.7 5 ment and application methods will Tractor system into an autono- 4 largely dictate an operation’s complexity mous unit. Additionally, BP and technical challenge, when deploy- trade-marked the term “Wireless 3 ing coiled tubing, hydraulic workover or Wellwork,” for use in all down- 1.8 2 wireline/slickline methods. Increasing hole operations, where a physi- 1 ?

1 use of light well intervention vessels cal link to surface was not used. 0.3

Customer relative cost (WL =1) 0

Welltec also moved to adopt the

SlicklineWireless WirelineWireline Coiled Snubbing tractor tractor tubing service “independent well trac-

Image: Welltec.

Conveyance method toring” or IWT.

The project aligned both company’s goals to establish a robotized means of intervention—i.e. carrying out activities without any physical links to surface, while providing data from the tools to surface, and ultimately being able to optimize the tool from an onshore desktop. Further development could result in robots “living” within the well space, to be activated as and when they are required to undertake either mechani- cal or surveillance functions.

Key advantages of this technology are, according to the project partners: •

Improved safety – with no wireline connections to surface, other than for deployment and recovery; reduced personnel on location; less complex rig

Wireless tractor on catwalk prior to picking up to the uptime and equipment; no requirement rig ? oor at onshore well test site. Photo: BP. for winches or complicated mast units;

March 2014 | OE oedigital.com 44 044_0314_ProdOps1_BP.indd 44 2/21/14 12:39 PM