Patent ID: 9744731
Date: 2017-08-29
CPC Classifications: B29C,B29D,B29K,B29L

Claim:
1. An installation for producing a biaxially oriented tube from thermoplastic material comprising: an extruder with an extruder die head having an inner die member adapted to extrude a tube in preform condition from a thermoplastic material, the inner die member forming a lumen in the tube; one or more tempering devices for temperature conditioning the perform, so that a tempered tube in preform condition is obtained having an orientation temperature suitable for the thermoplastic material; and an expansion device downstream of the extruder, the expansion device comprising: a cooling device adapted to cool the biaxially oriented tube; wherein the run-on part is provided with a sealing member that is adapted to be sealingly engaged by the tube in preform condition, the sealing member being arranged upstream of the expansion part of the expansion device and having a diameter that is greater than the run-on part downstream of the sealing member, the sealing member forming an effective seal that prevents the fluid volume from reaching the lumen of the tube in preform condition upstream of the sealing member, and the sealing member being arranged at the nose-end of the run-on part; and wherein the installation is absent an external part at the height of the sealing member that presses the tube in preform condition onto the sealing member.