Page 52: of Offshore Engineer Magazine (Aug/Sep 2014)

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Drilling

Metal-to-metal completion technology

Well integrity has been defned by a reactive approach and the limitations of current well planning and intervention technologies.

Mark Rivenbark looks at an alternative approach. integrity – particularly since Macondo – ne of the biggest issues fac- questions still remain as to well integri- ing the offshore oil and gas ty’s role in the well’s lifecycle. Questions

O sector today is well integrity. include: What exactly is well integrity

This challenge was made apparent by a and when does it start in the well lifecy- study conducted on a number of wells cle? Is it possible to protect it and at what on the Norwegian Continental Shelf by stage? And how can a safe and effective

Norway’s Petroleum Safety Authority balance be found between protecting well (PSA), which found that every ffth well integrity while maximizing production? analyzed had well integrity weaknesses.

Robust well integrity

Regulatory requirements, in the North

Sea and Gulf of Mexico in particular, Sadly, many older wells were not are increasing the onus on operators to designed for long life, so in some ways establish structural integrity and contin- they were destined for early failure from gencies at the planning stage; recomplete the outset. Well life cycles of 30-50 years existing producing wells to comply with are what is needed in many producing new legislation; ensure that well integrity felds around the world. These life cycles is not compromised by trouble zones and are achievable. Many studies based on stuck casing; and reinstate well integrity statistical data have been conducted quickly when damage does occur. over the years in an effort to understand

Despite the growing importance of well the causes of casing failure and possible solutions. This has involved the study of large data sets gathered over many years

Metalmorphology is the process of of production. shaping metal downhole to provide a metal-to-metal, gas-tight seal for the life

For external corrosion of wellbore of the well. Photos from Meta.

casing and strings, caused by corrosive

August 2014 | OE oedigital.com 54 054_OE0814_D&C2_Meta.indd 54 7/22/14 6:24 PM