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 compartment for the heat generating mixture; - an anchoring device connected between the upper connection section and the main housing section; wherein the main housing section comprises a compartment subsection and a distance subsection, where the compartment is located within the compartment subsection and where the distance subsection is located above the compartment subsection characterized in that - the anchoring device comprises: - an upper link element pivotably connected to the upper connection section; - a lower link element pivotably connected to the distance section; a radially outwardly facing surface with serrations for engaging the well pipe in the set state; wherein a length of the upper link element is longer than a length of the lower link element; - a weight of the main housing section is configured to pull the anchoring device to a radially retracted state when the well tool device is suspended from a wire or wireline connected to the upper connection section; - a weight of the upper connection section is configured to push the anchoring device to a radially expanded state when the well tool device below the anchoring device is held stationary with respect to the well pipe; - the well tool device comprises a wheel section comprising a set of wheels; - the wheels are provided a first radial distance from a longitudinal center axis (I-I) of the well tool device, wherein the radially protruding surface is provided at a second radial distance (r22a) from a longitudinal center axis (I-I) of the well tool device, the first radial distance being larger than the second radial distance (r22a). - an upper connection section; - a main housing section comprising a compartment for the heat generating mixture; - an anchoring device connected between the upper connection section and the main housing section; wherein the main housing section comprises a compartment subsection and a distance subsection, where the compartment is located within the compartment subsection and where the distance subsection is located above the compartment subsection characterized in that - the anchoring device comprises: - an upper link element pivotably connected to the upper connection section; - a lower link element pivotably connected to the distance section; - the anchoring device comprises: - an upper link element pivotably connected to the upper connection section; - a lower link element pivotably connected to the distance section; a radially outwardly facing surface with serrations for engaging the well pipe in the set state; wherein a length of the upper link element is longer than a length of the lower link element; - a weight of the main housing section is configured to pull the anchoring device to a radially retracted state when the well tool device is suspended from a wire or wireline connected to the upper connection section; - a weight of the upper connection section is configured to push the anchoring device to a radially expanded state when the well tool device below the anchoring device is held stationary with respect to the well pipe; - the well tool device comprises a wheel section comprising a set of wheels; - the wheels are provided a first radial distance from a longitudinal center axis (I-I) of the well tool device, wherein the radially protruding surface is provided at a second radial distance (r22a) from a longitudinal center axis (I-I) of the well tool device, the first radial distance being larger than the second radial distance (r22a). - a weight of the main housing section is configured to pull the anchoring device to a radially retracted state when the well tool device is suspended from a wire or wireline connected to the upper connection section; - a weight of the upper connection section is configured to push the anchoring device to a radially expanded state when the well tool device below the anchoring device is held stationary with respect to the well pipe; - the well tool device comprises a wheel section comprising a set of wheels; - the wheels are provided a first radial distance from a longitudinal center axis (I-I) of the well tool device, wherein the radially protruding surface is provided at a second radial distance (r22a) from a longitudinal center axis (I-I) of the well tool device, the first radial distance being larger than the second radial distance (r22a).