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Subsea BOP use from a HDJU on an HPHT well
26 August 2020
Hi,

Currently there is not an 18.75" HP Riser system on the market in the UK region that is rated for >12,500psi.

I'm looking for any feedback from the forum about any experience (good and bad) gained when using a SS BOP from a Jack-up. 
  1. What drove you to making the decision to run or not run a SS BOP in this manner?
  2. What were the lessons you learned towards repeating or not repeating the use of the SS BOP from a Jack-up?
  3. What kind of duration was required to source bespoke equipment and make any necessary modifications to the rig?
  4. Using the SS BOP in this manner in harsher environments like the North Sea are of particular interest but feedback from other regions will also be most welcome.
Thanks

Ron
7 answer(s)
cmcandrew
SPREAD Associates
Total Posts: 39
Join Date: 16/08/10
80 m WD, likely keeper. Look at simplest options first- as in use old JU as production or bring to surface to tie back to main platform.
Punch
Managing director Punch Energy Services
Punch Energy Services
Total Posts: 11
Join Date: 24/06/20
Hello Ron,

Have you checked with Claxton and Aquaterra as well?

Or perhaps there are alternatives from other regions? Do not know when this project is scheduled but if anyting suitable in another region there may be time to get it across? Expect cost of shipping would be less compared to a subsea BOP.

We could perhaps assist sourcing, just let me know if we can be of service.

Best regards,

Marcel de Klerk
Steve
Independent Consultant
SPREAD Associates
Total Posts: 4
Join Date: 12/07/11
Ron

This maybe a little off the subject, but a 13 5/8” subsurface BOP was actually rigged up as a surface BOP in the early 2000's offshore Indonesia on semi-submersible rig Sedco Rig  601.  This was done to facilitate a 13-3/8" drilling with casing (DwC) operation  to eliminate the 30" conductor string and  to replace the 20" surface string.   Being a known shallow gas hazard area, by drilling in the 13-3/8" casing, the risk of a well control event was minimized as conventional  tripping and running  casing ops. were eliminated.  Attached is the related technical paper for your reference.

Steve Rosenberg
Scott_McNeil
Consultant
SPREAD Associates
Total Posts: 155
Join Date: 05/03/08
Hi Ron,

Unless I'm completely missing the point, I'm with Peter on this one.

What is the downside of using a mudline suspension system with an adaptor that enables a subsea tree to be run on it afterwards if the well turns out to be a keeper?

This has been an option for a long time - I looked at it for a couple of wells in the SNS back in the late 80's.

If I recall correctly, it was Plexus who we were in discussions with about using their system.

As Simon mentioned, Maersk modified a couple of their JU's to be able to W/O or P&A subsea wells, but if I recall correctly, they were slimmed down BOP systems as no drilling was involved.

In any case, legislation changes since then would, I suspect, result in them lacking the capability to run the required number of rams to drill and HPHT well.

All the best

Scott
Ron.Mackay
Rig Intake Advisor
SPREAD Associates
Total Posts: 16
Join Date: 06/01/07
Why indeed Peter. I hear you, why indeed!!

Simply exploring possible options at this time.

It was done a while back in 2001/2 from a Maersk Drilling HDJU in Norway with a 15k stack.
To repeat would be an expensive exercise with any rig to make the various mod's plus the duration in the yard to complete same.

We are looking at various options to drill an HPHT subsea (potential keeper) well.

As I indicated in my initial question to the forum there isn't currently a fully qualified 15k HP Riser system on the market in the UK region. However, there may be one by mid to late 2021....

The other more obvious option would be to use a semi-sub but in 80m WD using RCD in the Marine Riser within an MPD setup. You'll remember a question on this to the forum several weeks ago that provided quite strong advise to avoid this option also.

The HP Riser qualification ticking all the boxes makes the other two options go away.
I'd be very keen to hear from you or others if they are aware of a "fully" qualified 15k HPR system that's out there or will be for 2021. 

Regards

Ron
Simon.Lucas
Well Engineering Mgr
Zenith Energy Limited
Total Posts: 9
Join Date: 13/09/07
Morning Ron

Have you talked to Maersk drilling contractors?  I think they are probably furthest ahead with jackups capable of handling subsea wellheads and BOPS, as they modified several jackups to be able to work over and abandon subsea wells. 
They may have a line on riser availability. 
My thought would be subsea wellhead, riser then surface BOP/MPD would be the way to go. 

The older generation systems used by CoP used a low pressure riser with a higher pressure riser inside, but I don't have the details - try and track down a former CoP hand (Allan Cross?)






Companyrep
Drilling Specialist/Well Engineer/Training Consultant
Kingdom Drilling
Total Posts: 486
Join Date: 10/01/05
Confused Ron,

A 15k SBOP on a jack up must have a 15k capable well and casing system below it. 

Where the wellhead and casing components must meet the worst case surface pressure that could be experienced At surface.. 

Also My understanding is that several companies make bespoke HPHT riser systems for jack ups to tie HPHT and subsea wells back to the SBOP. 

From a well control perspective alone it’s far better to have a SBOP vs. Subsea BOP. 
It’s also far easier to install a MPD systems at surface etc. 

Resolving the technical pipe issues from
thr seabed to the Texas deck is surely the cheaper and better technical solution vs trying to run a SSBOP on a jack up? 

Unless I’m missing something here? 

Ie Why Would we want to run a SSBOP from a jack up? 

Regards,




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