Abstract: Disclosed herein is a heat exchanger with a housing casing, a first base and a second base with openings, pipes as a first flow channel for conducting a first fluid, the ends thereof being arranged in or on the openings of the first and second bases, the pipes and the first and/or the second base are arranged within the housing so that a second flow channel for conducting a second fluid is designed between the housing and the pipes, a first inlet opening for the first fluid, a first outlet opening for the first fluid, a second inlet opening for the second fluid, a second outlet opening for the second fluid, a first diffusor for directing the first fluid into the pipes, a second diffuser for directing the first fluid out of the pipes, which heat exchanger should be simple and cost-effective to produce and ensure reliable operation.

Abstract: The invention relates to a device for cooling waste gas, comprising an inlet area (1) for guiding a flow of waste gas, an outlet area (2) for discharging the optionally cooled waste gas, and a longitudinal housing (1) for receiving exchanging means (13) for heat exchange. The flow of waste gas flows through the exchanging means (13) on the way from the inlet area to the outlet area. The inlet area (2) and the outlet area (3) are arranged respectively on end areas of the housing (1) which are opposite in relation to the longitudinal direction. The flow of waste gas flows through the exchanging means (13) on a first flow path (16) and also on a second flow path (17) which is counter thereto.