a method for positionally securing two components together , in which a hollow body is introduced into the two components . once the final position of the components relative to one another has been established , the hollow body is driven directly into the second component with the application of axial pressure and sonic energy . the method is suitable for employment with thermoplastic components whose relative position to one another is known beforehand , an example being in the assembly of housing parts of a rotary adjuster for controlling a flow cross section in internal combustion engines .