Abstract: A heated tank such as in a railroad tank car has a heat exchanger spaced from the bottom of the car to define a dead air space to insulate the heat exchanger from the bottom. The heat exchanger extends substantially longitudinally and transversely across the entire bottom of the car to provide a large heating transfer surface to the lading supported by the exchanger. A portion of the exchanger substantially encompasses a discharge valve of the tank car to provide heat transfer to the valve during unloading. The heat exchanger slopes toward the discharge valve to facilitate total removal of the lading. An inlet and an outlet associated with the heat exchanger are disposed adjacent the discharge valve for additional transfer of heat to the discharge valve. Baffles in the heat exchanger define a plurality of serpentine passages for conducting a heating medium.

Abstract: A heated tank such as in a railroad tank car has a heat exchanger spaced from the bottom of the car to define a dead air space to insulate the heat exchanger from the bottom. The heat exchanger extends substantially longitudinally and transversely across the entire bottom of the car to provide a large heating transfer surface to the lading supported by the exchanger. A portion of the exchanger substantially encompasses a discharge valve of the tank car to provide heat transfer to the valve during unloading. The heat exchanger slopes toward the discharge valve to facilitate total removal of the lading. An inlet and an outlet associated with the heat exchanger are disposed adjacent the discharge valve for additional transfer of heat to the discharge valve. Baffles in the heat exchanger define a plurality of serpentine passages for conducting a heating medium.