Process for producing a welding neck for solids transportation pipes as well as a welding neck for such pipes

摘要

It is known to allocate adaptor pieces to pipe ends that are in each case composed of an internal sleeve of high wear-resistant steel and of a jacket-side bushing of a weldable steel. The two cylindrical parts are pressed against one another. In this way the service life of the whole pipe can be extended. According to the invention however welding necks 1 are now used whose dimensions are purposely chosen so that the internal sleeve 5 and jacket cylinder 6 can easily be inserted into one another with sufficient clearance. The internal sleeve 5 is then repeatedly successively hardened, whereby it expands stepwise and bears in a flush and adherent manner on the jacket cylinder 6. The satisfactory fixing of the internal sleeve 5 in the jacket cylinder 6 thus occurs exclusively through hardening processes. The jacket cylinder 6 is then firmly joined with the solids transportation pipe 2 by means of a weld seam 10 between the surface 9 of the pipe 2 and the end face 7 of the welding neck 1. <IMAGE>