Skip to main content
European Commission logo print header
Contenuto archiviato il 2022-12-27

USE OF COMPOSITE CASING LINERS TO PREVENT CORROSION IN INJECTION WELL AT MAISONS-ALFORT

Obiettivo

To prevent corrosion problems due to stray currents and geothermal water charged with dissolved gases (H2S-CO2) and bacterial activity by lining the steel casing with composite tubes. Injection well of doublet exploiting the Dogger reservoir showed continual leakages, preventing a correct exploitation - even with classical repair. The composite tubing in 10 "3/4 and "7 diameter made of fiber glass (70%) and epoxy (30%) will be lined in the existing steel string.
The repair of injection well would secure doublet productivity and avoid high maintenance costs. One of the first applications of composite tubing for geothermal wells in Europe.
First of all, it has been difficult to remove the old steel liner (0 - 130 m), as the packer could not be dismantled. The pipes have been cut, the packer was hovered and pulled out to 13" 3/8 (900 m).
The cleaning of the well has been satisfactory. The packer setting and its anchoring at 1740 m, and the running-in hole of the composite string have been realized in very good conditions. After the wellhead setting and squeeze, the packer has slided down with the composite string on 23 m. The string has been pulled out the well, the packer pushed down into the well bottom and the doublet has been put on stream again.
A thorough enquiry has allowed to prove the delivered packer did not correspond to the ordered one.
A new attempt took place in September-October 1990, but only with pipes A (0 - 900 m). The setting up of the new packer, integral casing packer DAVIS LYNCH has needed two interventions, the first one having failed after the untimely ejection of the seat and bill.
The second intervention has seemed to be positive. After the running-in of the string, tests have shown a leakage in the annular space.
The packer did not make the lower tightness. So, it has been decided to pull out the string after the second lining attempt failure.
The doublet has been immediately put on stream again.
In spite of these two attempts failure, the composite liner must not be abandoned. In both cases, the failure is imputable to the packer and not to pipes. Strength tests realized on the pipes, after their fall into the well and their pulling out, have shown pipes had not be affected by the incident and kept all their characteristics.
The project has included the following phases :
1. Preparation of the project : specification sheets for the sizing of composite pipes, calculation note, strength tests, establishment of the programme, signing of supply contracts. January 1988 - June 1989.
2. Composite pipes manufacturing : 200 mm inner diameter pipes A for the the upper part of the well (0 - 900 m) and 150 mm inner diameter pipes B for the lower part (900 - 1750 m), and their accessories, July, September 1989.
3. If necessary, modification of the injection pump to cope with the pressure drops increase due to the useful diameter reduction. After the works.
4. Lining operations : October 1989.
After the withdrawal of the initial steel liner (0 - 130 m), cleaning of the well, setting of the packer. 5. Monitoring and inspection to check the composite string good holding :
setting up of strain gages, monitoring of operating parameters and tightness. Estimated operational time : 12 months after the setting up.

Argomento(i)

Invito a presentare proposte

Data not available

Meccanismo di finanziamento

DEM - Demonstration contracts

Coordinatore

SYNDICAT MIXTE POUR PRODUCT. ET DISTRIB.
Contributo UE
Nessun dato
Indirizzo
15 bis rue parmentier
94700 Maisons-alfort
Francia

Mostra sulla mappa

Costo totale
Nessun dato