| 摘要 |
The method for continuously applying a protective coating (4) containing an additive material to a welding seam (3) of a product made of from a galvanized steel sheet (1), comprises guiding a plasma beam (5) along the welding seam, where the continuously feed additive material is introduced using the plasma beam at the melting temperature of the additional material, wetting the welding seam in a liquid state without reaching the melting temperature of the steel sheet, and locally heating the welding seam by the plasma beam, which is directed to the welding seam. The method for continuously applying a protective coating (4) containing an additive material to a welding seam (3) of a product made of from a galvanized steel sheet (1), comprises guiding a plasma beam (5) along the welding seam, where the continuously feed additive material is introduced using the plasma beam at the melting temperature of the additional material, wetting the welding seam in a liquid state without reaching the melting temperature of the steel sheet, and locally heating the welding seam by the plasma beam, which is directed to the welding seam. The produced product is a profile and the additive material is tin alloy, whose melting temperature lies under the melting temperature of the zinc, where all joining- and/or reshaping steps of the profile production are already carried out before introducing the tin alloy and the tin alloy is low-alloyed tin or pure tin. The plasma beam is surrounded by a protective gas sheath. A flux material is simultaneously supplied with the tin alloy, which is continuously supplied as continuously feed wire and/or as powder, where the powder contains components of a paste containing flux material. The paste is supplied by a small tube. The welding seam and the supplied tin alloy are heated by the plasma beam. The supply of tin alloy takes place after the local heating of the welding seam and in direct vicinity to the plasma beam, where the tin alloy melts during impinging to the welding seam and wets the welding seam. The welding seam is heated strongly, so that a zinc layer (2) melts at the edges of the welding seam and forms a tin-zinc alloy in a transition area with the supplied tin alloy. The welding seam is heated strongly, so that the liquid tin alloy completely wets the welding seam, where the welding temperature of the zinc layer is not reached at the edges of the welding seam. The introduction of the tin alloy directly takes place after creating the welding seam in a common working step, where the devices are mechanically coupled with one another for the introduction of the tin alloy and the creation of the welding seam. |
