Abstract: A heat transfer apparatus adapted for installation in a mobile liquid container such as a railroad tank car. The apparatus includes inlet and outlet ports at opposite ends of a continuous finned pipe. The continuous finned pipe extends within the container to provide a surface for conductive heat transfer from the heat transfer fluid flowing through the pipe to the contents of the container.The continuous finned pipe is provided with shock absorbers and flexible loop portions to prevent damage to the apparatus from inertial shocks to the container. A preferred embodiment is designed particularly for use in railroad tank cars adapted to carry molten sulfur. The apparatus is used to remelt the sulfur, which has solidified in transit, for unloading.