Technology helps improve reliability and increase versatility in deepwater operations
The capability to reliably deploy large-bore hangers in offshore applications is critical to project success (McCormick et al. 2013). This case study discusses the the deployment of a large-bore expandable liner hanger (ELH) for the first time in a West African country and how the deployment of a 16-in. liner inside 20-in. casing at a water depth of 1,752 m was made possible by the use of an ELH system first deployed in 2010. Some of the design features critical to this application, initial preparation and mobilization of the ELH system in a remote location, and the execution of the job will be discussed.
The system was assembled, inspected and tested using a mobile workshop as a contingency hanger for an offshore well on the Ivory Coast. When a conventional hanger could not be set and the running tool parted in an offshore well elsewhere in West Africa, the well was ultimately abandoned and a second well spudded. The large-bore ELH system was shipped from Ivory Coast to the other country for installation in the new exploratory well, which was constructed using a fifth-generation drill ship. The cement job was challenging, with a significantly higher density of cement over the well fluid, which caused the string to rise in the rotary table while pumping the cement job.
This case study specifically addresses issues observed when running a conventional hanger by providing a large-bore ELH with a smooth profile, resulting in lower pressure losses and significant tensile capacity for the hanger and service tool. Equally important is the tensile capacity of the hanger resolved a problem seen with a different hanger in the previous 16-in liner run. The system used to run this expandable liner hanger also resolves the problems often experienced offshore when attempting to seat a casing or liner hanger in an exact location, such as a mud line receptacle. This system allows the liner hanger to be placed anywhere in the parent casing (Johnson et al. 2011).
This paper discusses information that will help to increase operator awareness concerning alternatives to traditional liner-hanger methods. As the industry pushes further into deepwater exploration and developmental wells, solutions for improved reliability and increased versatility are being implemented. ELH large-bore technology will help to increase the versatility and efficiency for current operations by improving liner-hanger placement flexibility, increasing the maximum-allowable flow rate, and providing more efficient zonal isolation.
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Source: SPE/IATMI Asia Pacific Oil & Gas Conference and Exhibition, 20-22 October 2015, Nusa Dua, Bali, Indonesia
Authors: John McCormick (Halliburton) | Alex Seinuah (Halliburton) | Ryan Humphrey (Halliburton) | Manfred Bledou (Total)