Fremgangsmåde til sammenføjning af oven på hinanden liggende metalplader og et værktøjssæt til fremstilling af sådanne sammenføjninger

摘要

A method and a tool set for joining superposed metal sheets are disclosed. In a first step, a preferably ring-shaped free space is provided by dislocating material of at least one sheet. Thereafter, material of all sheets is squeezed within the confines of the free space whereby material flows laterally into the free space producing an interengaging form lock.