We can all benefit from reduced pressure

We’re eliminating sustained casing pressure – today

What is sustained casing pressure?

Sustained Casing Pressure (SCP), also referred to as Sustained Annular Pressure (SAP) or Annulus Pressure Buildup, affects >30% wells globally and is present within multiple annuli.

Since 2009, well integrity has cost operators over USD 75 billion and this has provided the impetus for the industry to focus on and rework, international standards on well integrity management.

Gas migration through leaking cement sheath

SCP is excessive casing pressure in wells that persistently rebuilds after bleed-down. 

It is defined as a pressure in any well annulus that is measurable at the wellhead and rebuilds when bled down, not caused solely by temperature fluctuations or imposed by the operator.

SCP is caused by gas migration from a high-pressured subsurface formation through the leaking cement sheath in one of the well’s casing annuli.

In contrast, an unsustained casing pressure determination is made if either the casing pressure on a well is self-imposed (e.g. gas-lift pressure, gas- or water-injection pressure) or if the pressure is entirely thermally induced.

It may also be caused by:

  • defective or leaking tubing connections, downhole accessories or wellhead seals
  • degradation or failure of well barriers
  • leaks that develop either due to:
    • poor primary cementing job
    • temperature and pressure fluctuations during production
    • corrosion/erosion of casing or tubing
    • other type of Well integrity failures

Source: https://www.norskoljeoggass.no/

Why is SCP a problem?

SCP in any well means that well integrity has already been compromised.

Poor well integrity poses a number of serious health, safety and environmental risks for operators. From risk of contaminating groundwater to major blowout catastrophes.  

Prevent underground blowout

Industry experience with issues resulting from SCP/SAP has shown that the most serious problems have resulted from poor cement bond on the outer casing string, outside the production casing.

When the resulting pressure causes a failure of the production casing, the outcome can be catastrophic. The outer casing strings could also fail, resulting in an underground blowout. 

Prevent underground blowout!

By deploying WAB for Well Construction and Integrity

Eliminate greenhouse emissions from abandoned wells

Considerable number of producing and abandoned wells with SCP constitute a potential new source of natural gas emission from failed casing heads due to leaking cement sheath and external gas migration. Natural gas or methane emissions have a powerful negative effect on our climate that is 50-70 times that of CO2. It is estimated that methane is the single largest source of indirect greenhouse gas emissions from global oil and gas production. 

Eliminate greenhouse emissions from abandoned wells!

By deploying WAB for Well Abandonment

Eliminate risk of water breakthrough

With the continual increase in water production from maturing reservoirs comes the expense of installation of surface handling equipment, disposal and environmental concerns and a reduction in production efficiency from hydrocarbon producing wells. 

Eliminate risk of water breakthrough!

By deploying WAB for Zonal Isolation

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Our solution to SCP

Reliable and effective annular barriers continue to be critical to well management for safety and performance. Cementing has been the industry’s conventional means of creating these barriers, having been used for almost 100 years (American Oil & Gas Historical Society 2015). However, the industry is not drilling and completing wells the way that it did a century ago. Nearly every aspect of the well construction phase has long evolved.

The advances in drilling, particularly those related to horizontal well technology, have led to well designs and completion environments that often exceed the capabilities of cement to provide a reliable annular barrier that will last the entire well life.

Efforts to overcome the challenges of many of today’s wells with cement can lead to complicated, expensive, and time-consuming operations.

Welltec® Annular Barrier

At Welltec®, we design and test our Welltec® Annular Barrier (WAB®) range in accordance to IS0 14310, the industry standard which defines packer design validation grades. 

Our V0* WAB range for cased hole SCP barrier has been tested to IS01410 V0*, the highest validation level within this industry standard, and provides, a verifiable, life of well barrier against sustained casing pressure.

Reduce cementing operations

Welltec technologies eliminate or reduce the need for cementing operations. Deploying any of the the unique WAB range can:

  • Reduce operating time by 10 - 15%, offering equivalent reduction in rig-time, cost and the GHG footprint.
  • Minimize the weight of rig supply boats burning fuel
  • Decrease risks of cement spills in open water
  • Reduce cement clean-out in rig piping systems
  • Eliminate clean-out of contaminated tanks and pits
  • Cut the need to ship contaminated water ashore

Welltec's first deployment of a cementless completion took place in the Republic of Congo in early 2019. The deployment was deemed a success and since then, multiple repeat deployments are taking place in both injector and producer wells.

Read more about Welltec first cementless completion

Welltec® Annular Barrier to prevent SCP


  • IS0 14310 V0* cased hole SCP barrier
  • IS0 14310 V3* open hole SCP cement assurance
  • IS0 14310 V3* standalone open hole SCP isolation     
  • Platform for 2nd stage cement
  • Cross flow isolation
  • Open hole fault isolation plug
  • Casing hanger
  • Future-proof cap rock P&A
  • WAB can be incorporated within open hole, cased hole and hostile environment


  • IS014130 leak rate criteria - V0, V3
  • Verified isolation at installation when coupled with Welltec® Data Monitor
  • Rugged, all welded, metallic construction
  • High expansion capability
  • Slim RIH OD
  • Full bore - as per casing / tubing
  • Rapid, surface-controlled setting
  • Integrity protection as standard


  • Life of well isolation
  • Constant, high pressure ∆p over full expansion range
  • High rate circulation capability during deployment
  • Removes channels or leak paths at set depth
  • Rapid set WAB expedites time to next hole section
  • Sour service / NACE compliant
  • No premature expansion
  • No slumping of primary or secondary cement during curing
  • Provides confirmed foundation for placement of P&A cement plugs
  • Designed for rotation during deployment enhancing primary cementing