P1 provides key insight to enable complex well re-entry

OVERVIEW

iQx™ has enabled an operator to evaluate all possible outcomes for a range of proposed solutions for repairing a seriously damaged well. By providing key real-time data, iQx™ P1™ proved invaluable in helping reach the right intervention decisions quickly in a critical situation.

 

THE CHALLENGE

Facing an unpredictable intervention outcome

 

The job of well intervention is never straightforward. Choosing the best re-entry method for a well is often a complex, intricate task that can have numerous unpredictable outcomes.

This case study takes us into the Timor Sea, above the Northern Territory of Australia and focuses on the challenges faced in a well failure caused by a problem with the tubing-retrievable safety valve (TRSV).

The well was a standalone campaign for a small operator and so it was vital that first time re-entry is achieved successfully. 

 

OUR SOLUTION

A fast and thorough route to the evaluation of every risk

 

The operator chose iQx™ P1™ due to its application of Monte Carlo simulation deriving probabilistic modelling.

Through the capture of real-time data, P1™ was able to generate a deep understanding of well construction risks - whether operational or financial. P1™ proved to be a powerful technology that helps businesses to quantify, prioritise, manage and communicate project risks to key stakeholders. 

In this scenario, P1™s scalable functionality was utilised to comprehensively model the events surrounding bypassing or destroying the valve to gain well access and facilitate a SST change-out. 

Four methods to bypass the flapper valve were identified, ranging from a conventional mechanical lockout to a bespoke solution that used a downhole cannon to destroy the valve. The four possible bypass procedures identified presented 22 possible outcomes, which were factored into the modelling.

It was clear from this assessment that linearly modelling, for bypassing the TRSV, would not adequately address the risks involved in re-entering the wellbore and could potentially result in a failure to restore the well.

THE OUTCOME

 

The right intervention solution chosen and savings achieved

 

 

 

Through P1™, a representative time and cost estimate that considered all of the key risks was produced. This was used to raise an authorisation for expenditure and allocate an adequate contingency budget.

The prompting nature of the probabilistic model allowed the engineering team to brainstorm all possibilities thoroughly and build these branches into the model. If one method identified lacked supporting data when modelling success probabilities, investment in Simulation Integrated Testing (SIT) was made to provide additional data for milling operations using wireline deployed mechanical services tools.  

Additionally, the success of the SIT in completing data gaps shifted the hierarchy of intervention options in favour of the use of wireline over coiled tubing. This allowed the operator to achieve savings on the significant mobilisation costs associated with this type of equipment.

 

WHAT VALUE DID iQX™ BRING TO THE CLIENT?

  • Simple to use
  • Probabilistic and deterministic modelling capabilities
  • Enabled identification, prioritisation and mitigation of project risks
  • Created clearly presented flow diagrams and graphs to show processes
  • All information was captured in one convenient place
  • Empowered collaboration and was a vital stakeholder management tool