Patent ID: 6214283
Filing Date: 2001-04-10
Classification: B29C

Abstract:
Method for treating an extruded hollow plastic section which emerges in an extrusion direction from an extruder head connected to an extruder, said extruder head having a mandrel which forms a hollow space in said plastic section, wherein, downstream of said extruder head, a plurality of spaced apart closing means are kept stationary with respect to said extruder in said hollow space of said extruded plastic section, at least one sealed compartment being formed between two adjacent closing means, and wherein a section treatment medium is fed to said at least one sealed compartment for treating said plastic section, at least one of said closing means having a dimensionally rigid outer wall, said outer wall having such dimensions with respect to said hollow space of said extruded plastic section that said plastic section tends to frictionally engage said outer wall of said closing means, said closing means comprising first conduit means which open out into at least one supply orifice which is provided in said outer wall of said closing means, said first conduit means being connectable to fluid feeder means for feeding fluid to said first conduit means, and second conduit means being provided which connect to at least one discharge orifice for discharging said fluid, said discharge orifice being situated upstream of said supply orifice, wherein said fluid is forced between said outer wall of said closing means and said plastic section, such that said fluid forms a fluid film between said plastic section and said outer wall between said supply orifice and said discharge orifice, said fluid being passed countercurrent to said extrusion direction of said plastic section, between said closing means and said plastic section.