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

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.

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.