CT in Subsea Riserless Interventions Reduces Time 40% P&A Operations | SLB

CT in Subsea Riserless Interventions Reduces Time During P&A Operations by 40%

Published: 02/08/2016

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Graphic: CT in Subsea Riserless Interventions Reduces Time During P&A Operations by 40% - CoilTOOLS tools and solutions enable more efficient P&A operations, minimizing personnel and equipment exposure in 14-well campaign

Coil Tubing Services, a Schlumberger company, proposed CT riserless operations in P&A wells after the zonal and casing packer isolation had been successfully set and tested. Engineering and operational evaluations were performed to address CT string integrity, bottomhole assembly, surface CT stack rig-up, remote operating vehicle use to string the CT into the wellbore, CT depth correlation, cement slurry design, and proper fluid placement.

A total of 14 subsea CT riserless interventions have been completed as part of this campaign without HSE incidents or CT string failures, saving 40% in operational time and complying with federal safety regulations.

Location
Gulf of Mexico, United States, North America, Offshore
Details

Environment
Deepwater
 
Well depth
4,900-19,000 ft, [1,494-5,791 m]
 
Hole size
8.5 in [21.6 cm]

Background

Subsea riserless plug-and-abandon (P&A) operations are often completed by setting plugs with drillpipe after production tubing has been removed with the rig, and operations are performed in an average of 22 hours. An operator was seeking an alternative method to reduce the amount of time needed to perform P&A operations in its deepwater wells exceeding 3,500-ft [1,067-m] water depth, all while complying with federal safety regulations.

Products Used