Abstract: A device for introducing hot gas into a heating surface tube of a waste heat boiler having an outer tube connected to the boiler wall, in particular to the tube plate, has an inner or inlet tube that is connected to the outer tube by a rounded reversing cap to form an inlet port for the hot gas. The inner tube is surrounded by the outer tube at a distance and has an inflow section and an outflow section connected to the heating surface tube. The device further has a coolant transport tube, between the outer tube and the inner tube, that extends to the vicinity of the reversing cap. The inflow section and at least part of the outflow section of the inlet tube are conical in design, where the taper is less than 2° and the cross-section of the conical region of the inlet tube becomes smaller as it approaches the outflow section. The length of the conical region is at least four times the inner diameter of the inlet tube, and the conical region of the inlet tube is designed with at least two different tapers.

Abstract: A device for introducing hot gas into a heating surface pipe of a waste heat boiler includes an outer pipe that is connected to the boiler wall, preferably to the bottom of the pipe. The device also includes an inner pipe or entry pipe that has an admission section that is cylindrical or conically narrows and also has a discharge section that is connected to the heating surface pipe. The inner pipe is connected to the outer pipe via a rounded reversible cap while forming an entry opening for the hot gas. The inner pipe is surrounded by the outer pipe at a distance. The device also includes a coolant guiding pipe, which is placed between the outer pipe and the inner pipe and which extends into the proximity of the reversible cap.