Continuous perforation of undulating thin-walled thermoplastic pipes - by stamping units forming six-pointed star around pipe

摘要

Piercing tools are fixed to tool holders which are guided in cam tracks running obliquely to the axis of the pipe, in a machine for continuously piercing thin, undulating wall pipes, esp. drainage pipes of synthetic thermoplastics. The cam tracks are laid out so that at least in the working zone, i.e., immediately before, during and immediately after the penetration of the tool into the pipe wall, the tool holding blocks are guided so as to move only in the axial direction of the tools. Used piercing holes continuously through a thin walled, undulating pipe whilst ensuring that the holes are pierced accurately in the troughts of the undulations, without imposing excessive loads on the piercing tools. The machine is of simple design and operates reliably at high speed. In spite of the series of tool holding blocks, the whole stamping arrangement can be kept compact since, even whilst the tools are approaching the pipe, the piercing operation commences.