Well Integrity Technical Section

This message has been cross posted to the following Discussions: Well Integrity and Completions .
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Hello everybody,

I am looking for tips, field recommendations and operational procedures that can contribute to a procedure for testing wells with 15,000 psi. If any can help in this direction will be very helpfull.

I have some reference normative like Norsok D-SR-7, API-6A, API-14, but I would like to know if there are some special oriented to well testing for HPHT (examples: recommendation for chokes material, special anchoring for lines in surface, layouts, distances,...)

best regards



------------------------------
Sergio Chavez
Global Completion & WO Staff Engineer
Pluspetrol Intl. Inc.
Capital Federal
------------------------------

Sergio,

 Can you give a little more context; Onshore vs Offshore, FWHP and/or Shut-in Reservoir pressure, Test fluid Oil or Gas, H2S concentration, expected FWHT or BHT,  and any Logistical challenges?

Wellhead pressure is the most important as 15k FWHP may mean ~20K equipment for shut-in conditions. But high FWHT will influence equipment selection also. And, of course, high H2S concentration poses it's own risks and equipment selection.

HPHT well tests and equipment are very common and Onshore there is a wide range of available equipment.  Offshore, subsea wells, have a much smaller set of available equipment and require months of planning and lead time to acquire equipment and personnel.

------------------------------
Dan Gibson
Completion / Well Integrity Advisor
Gibson Petroleum Consultants
FulshearTX
------------------------------

------------------------------ Henry Adom-malm Managing Director Horizine Tech. Int. Gh Ltd. Accra ------------------------------
Original Message: Sent: Apr 11,2015 07:32 AM From: Dan Gibson Subject: HPHT Well Testing Sergio, Can you give a little more context; Onshore vs Offshore, FWHP and/or Shut-in Reservoir pressure, Test fluid Oil or Gas, H2S concentration, expected FWHT or BHT, and any Logistical challenges? Wellhead pressure is the most important as 15k FWHP may mean ~20K equipment for shut-in conditions. But high FWHT will influence equipment selection also. And, of course, high H2S concentration poses it's own risks and equipment selection. HPHT well tests and equipment are very common and Onshore there is a wide range of available equipment. Offshore, subsea wells, have a much smaller set of available equipment and require months of planning and lead time to acquire equipment and personnel. ------------------------------ Dan Gibson Completion / Well Integrity Advisor Gibson Petroleum Consultants FulshearTX ------------------------------
Original Message: Sent: Apr 10,2015 11:11 AM From: Sergio Chavez Subject: HPHT Well Testing This message has been cross posted to the following Discussions: Well Integrity and Completions . ------------------------------------------- Hello everybody, I am looking for tips, field recommendations and operational procedures that can contribute to a procedure for testing wells with 15,000 psi. If any can help in this direction will be very helpfull. I have some reference normative like Norsok D-SR-7, API-6A, API-14, but I would like to know if there are some special oriented to well testing for HPHT (examples: recommendation for chokes material, special anchoring for lines in surface, layouts, distances,...) best regards ------------------------------ Sergio Chavez Global Completion & WO Staff Engineer Pluspetrol Intl. Inc. Capital Federal ------------------------------

Dan,
Thanks for your comments.
Currently the well is shut down and the company decided the temporary abandonment while is looking for 20,000 psi BOPE.
The drilling was shut down at 6300 m (850 m Open hole) with a mud density of 17.5 ppg because some admissions and became a well control issue.
Mud logging give C1 from C5, no H2S and 5% CO2 max were detected.
Max temp detected by MWD was 136°C @ 5470 m (18,000 ft)

We also start the design / procurement for 20,000 psi well head and well testing service.

Any tips and recommendations will be welcome in order to complement our existing procedures.

Best regards

Sergio




________________________________
"Cuidar la naturaleza es vivir mejor... hagámoslo juntos. Imprime sólo lo necesario."


"La información transmitida en este mensaje está destinada únicamente a la persona o entidad a la cual el mismo está dirigido, y puede contener material confidencial, reservado o sujeto al secreto profesional. Cualquier revisión, retransmisión, divulgación u otro uso de la misma, o la realización de cualquier acción basada en ella por personas o entidades distintas de la indicada, no está permitida. Si usted ha recibido este mensaje por error, tenga la amabilidad de destruirlo, sin copiarlo ni divulgar su contenido. Muchas gracias."


The information contained in this message is directed exclusively to the person or entity to whom the message is addressed, and it might contain information that is confidential, privileged or otherwise legally exempt from disclosure. Any action based on it, performed by an individual or entity different from the one it was intended, is not allowed and its contents should not be read, forwarded, disclosed, or used in any other way. If you have received it by mistake please delete it from your system, you should also not copy the message nor disclose its contents to anyone. Thank you.

------Original Message------

------------------------------ Henry Adom-malm Managing Director Horizine Tech. Int. Gh Ltd. Accra ------------------------------

Sergio,

 

It sounds like you have encountered reservoir conditions that had a higher pressure than expected. That could be a very exciting  opportunity. 

 I did some rough math with your data and the BHP is roughly 18,800 psi. With a dry gas gradient of 0.15 psi/ft your shut-in WHP will exceed 15,000 psi.  You are planning to drill deeper.   I don't think you are looking at a 15K well test.  I think you need to consider a 20K well test similar to the 20K BOP/Choke system the drillers are using. 

This high pressure and change in equipment could mean that the original well basis of design is no longer valid.  The first thing I would do is rerun the well design assuming gas to surface and determine if the casing design and wellhead is still fit for purpose.  For a well test, where we purposely bring hydrocarbon to surface, we could have a tubing leak which applies full shut-in WHP on the annulus fluid.  This is normally a brine during a well test...but the well may still not be designed for these pressures. Since during the test any leak will trap the pressures between the well test packer and the wellhead it can't leak off and must be resisted by the casing and hardware. If it is not rated for full shut-in wellhead pressure a well test is not advised. 

Note: Drilling should also be looking at a similar analysis with a gas kick shut-in with pressures up to frac pressures.

Second, is looking at annulus pressure build-up in any trapped annulus during the well test.  As you produce the well during the test the well will heat up and the annulus fluids will expand.  If there are any trapped annuli these pressures can become very high during the test and result in casing failure.  Run WellCat or similar thermal modeling to analyze the well thermal performance.  Let me know if you have any questions on this.

Third, is well test equipment rated for the pressures you will see.  Normally, for hydrocarbons, you have to assume that there will be a gas gradient in the tubing when the well is shut-in during the well test.  Gas will breakout and rise to fill the tubing down to some depth...normally assumed to be the reservoir.  Your data suggest you might have a gas well (no oil mentioned).  This gas gradient scenario controls the design/selection of the tubulars and surface test kit.  The tubing and downhole test tools equipment have to be designed assuming full shut-in pressure.  The test tree and lines up to the choke manifold have to be designed for full shut-in well pressure.  Talk to the service providers about availability of 20K well test choke manifold, test tree, lines, downhole test tools, etc.  Look at your company inventory for XHPHT tubing string.  There are not very many of these XHPHT test spreads around the world and you will have to mobilize them to your location. This may take some time but may be better in the current market conditions.

Finally, the presence or lack of H2S is a key factor.  The drilling mud indicators may not be the best evidence depending on your mud system and how it is formulated.  Talk to the mud company about their system and make sure they are not scavenging H2S so that it is not seen. Assuming you don't have any H2S, the well test planning and operation is very straightforward. You will have to manage hydrates downstream of the choke as the large pressure drop will result in some Joules Thompson cooling.  The separation of liquids and flaring/storage are conventional operations.  The biggest challenge will be getting a well qualified crew to plan and execute this test....but again current market conditions allow you access to the skills you need.

 

I hope this gives you some ideas to consider.  I am sure others will add some comments. 

Please do not hesitate to ask if you have any questions,

------------------------------
Dan Gibson
Completion / Well Integrity Advisor
Gibson Petroleum Consultants
FulshearTX
------------------------------

Original Message:
Sent: Apr 16,2015 03:38 PM
From: Sergio Chavez
Subject: HPHT Well Testing

Dan,
Thanks for your comments.
Currently the well is shut down and the company decided the temporary abandonment while is looking for 20,000 psi BOPE.
The drilling was shut down at 6300 m (850 m Open hole) with a mud density of 17.5 ppg because some admissions and became a well control issue.
Mud logging give C1 from C5, no H2S and 5% CO2 max were detected.
Max temp detected by MWD was 136°C @ 5470 m (18,000 ft)

We also start the design / procurement for 20,000 psi well head and well testing service.

Any tips and recommendations will be welcome in order to complement our existing procedures.

Best regards

Sergio




________________________________
"Cuidar la naturaleza es vivir mejor... hagámoslo juntos. Imprime sólo lo necesario."


"La información transmitida en este mensaje está destinada únicamente a la persona o entidad a la cual el mismo está dirigido, y puede contener material confidencial, reservado o sujeto al secreto profesional. Cualquier revisión, retransmisión, divulgación u otro uso de la misma, o la realización de cualquier acción basada en ella por personas o entidades distintas de la indicada, no está permitida. Si usted ha recibido este mensaje por error, tenga la amabilidad de destruirlo, sin copiarlo ni divulgar su contenido. Muchas gracias."


The information contained in this message is directed exclusively to the person or entity to whom the message is addressed, and it might contain information that is confidential, privileged or otherwise legally exempt from disclosure. Any action based on it, performed by an individual or entity different from the one it was intended, is not allowed and its contents should not be read, forwarded, disclosed, or used in any other way. If you have received it by mistake please delete it from your system, you should also not copy the message nor disclose its contents to anyone. Thank you.