Well tool device for transporting a heat generating mixture into a well pipe

A well tool device for transporting a heat generating mixture into a well pipe, wherein the well tool device comprises:

• an upper connection section;
• a main housing section comprising a closed compartment which contains the heat generating mixture;
• and
• a sealing device provided below the main housing section;
• wherein the sealing device comprises:
• a lower supporting element comprising a lower wedging surface;
• an upper wedging surface faced towards the lower wedging surface;
• a sealing ring provided between the lower wedging surface and the upper wedging surface;
• wherein the sealing ring comprises a plurality of thimble-shaped elements inserted into each other to form a torus;
• wherein relative axial movement between the lower wedging surface and the upper wedging surface in a direction towards each other provides radial expansion of the sealing ring;
• and
• wherein a weight of the main housing section and the heat generating mixture is configured to force the sealing device from a radially retracted state to a radially expanded state when the lower supporting element is held stationary with respect to the well pipe.