Abstract: A process for welding synthetic resin structures together at their end faces, wherein the structures are clamped in position, the end faces are heated by being brought into contact with a heating plate until initial melting occurs, the softened end faces are pressed together and the weld bead is machined off, the structures are guided on at least two opposing outside surfaces up to the welding edge by guide means, with the melting zone being left vacant, and the softened end faces of the profile elements are pressed together approximately until the opposite outside guide means contact each other whereby the weld bead formation is restricted and the weld bead can be scraped off while the elements are still in the warm condition and a device for carrying out this process.