P&A Application in Norway North Sea

Well Abandonment with Wel-lok™ STC

Statistics

Location:
Norway
Environment:
Offshore
Deviation:
33º
Depth:
9850'
Downhole Pressure:
5350psi
Differential Pressure:
1500psi
Temperature:
89ºC
Setting ID:
6.435"
Restriction:
4.276"
Sealing ID:
8.535"

Identification of problem

A client required isolation in the uncemented annulus behind a 7 5/8” liner that was run inside 9 5/8” casing.

Issues to overcome

For proper well control, the client could not remove the 5 ½” tubing in the well which had a 4.276” ID mule shoe on the bottom and could not establish sufficient injection into the annulus to squeeze cement or resin. This required a tool with a maximum OD of 4.0” to set inside 7 5/8” liner and seal out to 9 5/8” casing through perforations without circulating or squeezing from surface.

Application

Wel-lok™ STC was set in a perforated section of the 7 5/8” liner to isolate the wellbore out to the 9 5/8” casing.

Outcomes/Conclusion

This tool was qualified to 1,500 psi differential pressure in 7 5/8” x 9 5/8” casings at our testing facility in Houston, TX. For field deployment, the perforation guns used perforated both the 7 5/8” liner and the 9 5/8” casing. As a result, the Wel-lok™ STC did not achieve a positive pressure test in the field deployment as it was not designed or qualified to seal beyond the 9 5/8” casing.

About the application

The Wel-lok™ STC (Seal Through Casing) has been developed to achieve a gas tight V0 seal well annuli that cannot be achieved by traditional cement balance plugs. Run on electric line, this tool does not need surface pumping equipment to circulate the alloy in place. Due to its viscosity and density, once melted the liquid alloy will flow with gravity into the annulus. When it cools below its melting point it solidifies, expands and creates a gas tight seal across the entire wellbore. The entire process, from melting to solidification, takes place in minutes and the seal is ready to test within an hour.

Seal Through Casing - BiSN
Seal Through Casing - BiSN
Seal Through Casing - BiSN
Seal Through Casing - BiSN

How it works…

The Wel-lok™ STC (Seal Through Casing) has been developed to achieve a gas tight V0 seal well annuli that cannot be achieved by traditional cement balance plugs.

Get in touch and find a
permanent solution for your well

Businesses worldwide are benefitting from BiSN's well services in the field. Contact us today and embrace tomorrow's downhole well solution, today.

This is a required field
This is a required field
Please enter a valid email
This is a required field
This is a required field

Don’t miss out on the latest technical updates and advancements. Subscribe today.

Please enter a valid email address.

Our website uses analytics, marketing and preference cookies to both provide the most relevant experience for our users and to give us information about how our site is used. By clicking “Accept All”, you consent to the use of these cookies. However, you may visit "Cookie Settings" to provide a controlled consent.

Accept All Cookies