Temperature activated zonal isolation packer device

Abstract

The present invention relates to a packer device () for sealing against an inner surface of a surrounding pipe or casing string (), preferably for isolating zones or sections in an oil well, comprising a tubing body () and at least one sealing element (), where a cylinder/piston arrangement () comprises a cylinder () having a closed volume containing a fluid, such as a gas or liquid, arranged to expand when exposed to heat thereby exerting a mechanically pressure on movable elements (), initially locked in a fixed position by means of at least one fixing element, such as a shear member (), and where the movable elements () are adapted to be released into an operative state at a predetermined axial force, exerted by the closed volume in the cylinder (), resulting in that the at least one sealing element () is pressed radially outwardly in such a way that it seals the packer device () against the surrounding pipe-/casing string (). The invention is achieved by that an endcap () is arranged to cover an internal piston () and minimize the area of the internal piston () that is exposed to the surrounding pressure in the well (PW) acting against the fluid pressure (P) inside the cylinder (). The invention also relates to a method for activating a packer device () to seal against the surface of a surrounding pipe or casing string () and the invention further relates to the use of such a packer device ().