Top facts you never knew about well integrity failure

Well integrity breakdown is a problem which has the potential to keep a lot of people awake at night. From drilling managers to corrosion experts to rig managers to company CEOs, and countless people in between, this is one of the most serious issues surrounding a well.

1- The geographical spread

· Over 6,650 active wells in the Gulf of Mexico have sustained annular pressure (45%)

· 34% of (UK) wells in the North Sea have integrity issues (1,600 wells)

· In the North Sea, 7% of Norwegian wells were completely shut in due to integrity issues, and an additional 11% have other integrity issues.

2- The main causes

· Tubulars: 41%

· Annular integrity/zonal isolation: 20%

· Safety & other control systems: 20%

· Corrosion: 14%

· Scale: 5%

3- Global figures

· 760,000wells globally are affected by integrity issues

· 9% are permanently shut-in

· 10% are temporarily shut-in

4- Costs

· The 19% of shut-in wells amount to approximately $1.09bn a day in lost revenue

(Calculated based on oil price, number of wells shut in, global average production)

Some of these facts are just staggering. The last amount of lost revenue is an approximate value, but shows how much of a huge strain on the industry integrity failures are. This does not include any amount of spending on rectifying problems, building relief or replacement wells, or dealing with lawsuits (in extreme cases).

It is impossible to pay too much attention to well integrity, and although sometimes running extra tests or precautions can slow production down by a day or two, surely it would be for the best in terms of costs, safety and overall production rates and ensure well integrity throughout the well’s life.

From the 1) US Minerals Management Service survey, 2004; SPE forum North Sea Well Integrity Challenges, 2009; Norwegian Petroleum Safety Authority, Well Integrity study, 2006; 2) OTM Consulting & Archer market survey 2010; 3) OTM Consulting 2009; 4) BP Statistical review of world energy 2010; US EIA-28, 2009: OTM Consulting 2011