WellMaster BOP

Structured results from numerous BOP reliability studies since 1983, helping to reduce downtime and testing cost of both subsea and topside BOP solutions.

  • Reduce rig downtime caused by BOP failures
  • Improve BOP stack ability to act as safety barrier
  • Reduce BOP testing cost
  • BOP reliability data collection since 1983

Key facts

More than


BOP Failures registered

BOP data collected for

Topside, Subsea & Deepwater

More than

30 years

of data collection

WellMaster BOP is a system for collecting and analysing failures on BOP solutions, based on data from operations and open sources.

Documented since 1983

ExproSoft has since 1983  documented results from a number of detailed reliability studies of blowout preventers (BOP), covering both subsea and topside solutions. Additionally, the company has inquired a substantial knowledge of BOPs and reliability assessment through numerous expert studies for oil and gas operators.

Data collection categories

Objectives of the WellMaster BOP are to:

  • Identify problem areas
  • Conduct analysis related to safety, reliability, and maintenance
  • Identify areas of technical and operational improvement

Data collection categories

BOP specific data:

  • Preventers
  • Valves
  • Controls

Other relevant data:

  • Rig (some key data only)
  • Operator (some key data only)
  • Contractor (some key data only)
  • Well and well casing

Kick & Blowouts

A well kick is a result of a instale well due to inflow of gas, oil or water. If Barriers should fail, may a kick result in a blow-out. Such a situation is defined as a sudden, powerfull and uncontroled release of gas, oil, drillingfluids or water from the well.

A blow-out occurs by loss of well pressure control during drilling operations. The causes of a blow-out may be technialfailure, proceduralfailure, to low fluid weight in well bore, stuck pipe – often a comination of factors.

The potential of a blow-out varies, amongst other related to the well design, fluid flow and reservoir properties.

How the kill a blow-out bepends on the situation – either closure of the BOP system, establish a release well or by bullheading.

“Industry averages show that BOP failures causes      1 hour daily drilling downtime”

Per Holand


Blowouts on the Norwegian Continental Shelf

In the operational phase, there has only been 1 major blow-out from an asset on the Norwegian continental shelf. It was a downhole valve in a production well that failed at the same time of a workover (Ekofisk Bravo Accident 1977). No people were killed, but during a week, 9 million kg`s of oil went into the sea before control of the well was re-established.

28th.  of November 2004 there was an underground gas blowout on the platform Snorre A. With slightly different  circumstances the blow-out could have lead to a major accident with loss of many lives. The Norwegian Safety Authorities (PTIL) uncovered as many as 28 deviations from the regulations. This was a serious reminder, both for the government and the industry, the failing well barriers may have fatal consequences for safety.

Blowouts in the Arctic

“Operators and service companies working in this emerging frontier require a range of new or modified technologies to succeed. First and foremost, they must develop and test blowout capping and containment systems designed specifically for arctic conditions. Spills among ice floes are much tougher to handle than spills in open waters”

Jeff Spath

2014 SPE President

The blowout preventer serves as the most important barrier when fluid control is lost.

Exprosoft hosts the SINTEF Offshore Blowout Database which is a comprehensive event database for blowout risk assessment.

The database includes information on 573 offshore blowouts/well releases that have occurred world-wide since 1955 and overall exposure data from the US Gulf of Mexico, Outer Continental Shelf and the North Sea. The blowouts/well releases are categorized in several parameters, emphasizing blowout causes. More info can be found on the SINTEF web-site.

Avoiding future accidents by learning from history