A device for forming a barrier in an annulus of a well

Abstract

A device is for forming a barrier in an annulus of a well. The device has an injection tool adapted to introduce a polymeric hardening liquid in through an opening in the annulus, and a pump unit adapted to provide pressure to said liquid so that the liquid is introduced into the opening in the annulus with a controllable pressure. The device has a control unit adapted to control the pump unit so that said liquid is provided into the opening with an initial pressure at a start-up phase of introducing the liquid into the opening and a final pressure at a close-down phase of introducing the liquid into the opening, wherein the final pressure is higher than the initial pressure.

1 . A device for forming a barrier in an annulus of a well, the device comprising:
 an injection tool adapted to introduce a polymeric hardening liquid in through an opening in the annulus, and   a pump unit adapted to provide pressure to said liquid so that the liquid is introduced into the opening in the annulus with a controllable pressure,   wherein the device comprises a control unit adapted to control the pump unit so that said liquid is provided into the opening with an initial pressure at a start up phase of introducing the liquid into the opening and a final pressure at a close-down phase of introducing the liquid into the opening, wherein the final pressure is higher than the initial pressure.   
     
     
         2 . The device according to  claim 1 , wherein the control unit is adapted to control the pump unit so that said liquid is provided into the opening with a gradual increasing pressure over time from the start up phase to the close-down phase of introducing the liquid into the opening in the annulus. 
     
     
         3 . The device according to  claim 1 , wherein the initial pressure is between 1-50 bar, preferably between 10-30 bar. 
     
     
         4 . The device according to  claim 1 , wherein the final pressure is between 2-400 bar, preferably between 30-250 bar. 
     
     
         5 . The device according to  claim 1 , wherein the control unit adapted to control the pump unit between the start up phase and the close-down phase of introducing the liquid to the opening at a time period between one hour and 72 hours, preferably between 12 and 48 hours. 
     
     
         6 . The device according to  claim 1 , wherein the device further comprises a device for forming said opening in the annulus. 
     
     
         7 . The device according to  claim 1 , wherein the control unit adapted to control the pump unit so that said liquid is provided into the opening in the annulus with two or more injection sequences with increasing pressure. 
     
     
         8 . An arrangement for forming a barrier in an annulus of a well, wherein the arrangement comprises a device and a polymeric hardening liquid, the device comprising:
 an injection tool adapted to introduce a polymeric hardening liquid in through an opening in the annulus, and   a pump unit adapted to provide pressure to said liquid so that the liquid is introduced into the opening in the annulus with a controllable pressure,   wherein the device comprises a control unit adapted to control the pump unit so that said liquid is provided into the opening with an initial pressure at a start up phase of introducing the liquid into the opening and a final pressure at a close-down phase of introducing the liquid into the opening, wherein the final pressure is higher than the initial pressure.   
     
     
         9 . The arrangement according to  claim 8 , wherein said liquid has a viscosity between 5−1*10{circumflex over ( )}6 cP at the start up phase of introducing the liquid to the opening, preferably a viscosity of between 15-20000 cP. 
     
     
         10 . The arrangement according to  claim 8 , wherein said liquid has a viscosity between 1*10{circumflex over ( )}6-10*10{circumflex over ( )}6 cP at the close down phase of introducing the liquid to the opening, preferably between 2*10{circumflex over ( )}6-5*10{circumflex over ( )}6 cP. 
     
     
         11 . The arrangement according to  claim 8 , wherein said liquid mainly comprises a thermoset material. 
     
     
         12 . A method for forming a barrier in an annulus of a well, the method comprises:
 positioning an injection tool at a position of an opening in the annulus for introducing a polymeric hardening liquid,   at a start up phase, introducing the liquid into the opening at an initial pressure, and   at a close-down phase, introducing the liquid into the opening at a final pressure, wherein the final pressure is higher than the initial pressure.   
     
     
         13 . The method according to  claim 12 , wherein the method comprises:
 gradual increasing pressure over time from the start up phase to the close-down phase of introducing the liquid to the opening.   
     
     
         14 . The method according to  claim 12 , wherein the initial pressure is between 1-50 bar, preferably between 10-30 bar. 
     
     
         15 . The method according to  claim 12 , wherein the final pressure is between 2-400 bar, preferably between 30-250 bar. 
     
     
         16 . The method according to  claim 12 , wherein a time period between the start up phase and the close-down phase of introducing the liquid to the opening is between one hour and 72 hours, preferably between 12 and 48 hours. 
     
     
         17 . The method according to  claim 12 , wherein the method comprises
 providing said liquid into the opening in the annulus with two or more injection sequences with increasing pressure.