초록 ▼

Apparatus for preparing seamless, creaseless, pliable, thin-walled tubes comprising means to extrude a moving continuous tube of polymeric film material from a die, means to radially stretch the continuous tube as it emerges from the die, means to longitudinally stretch the tube, and means to sever

Apparatus for preparing seamless, creaseless, pliable, thin-walled tubes comprising means to extrude a moving continuous tube of polymeric film material from a die, means to radially stretch the continuous tube as it emerges from the die, means to longitudinally stretch the tube, and means to sever the tube while the tube is in motion to form tube segments while maintaining the tube substantially free of creases. This apparatus may be employed in a process to prepare seamless, creaseless, pliable, thin-walled tubes.

대표청구항 ▼

A process for preparing seamless, creaseless, pliable, thin-walled tubes comprising extruding a continuous moving tube of polymeric film material from a die into the ambient atmosphere, radially stretching said continuous tube over a sizing disk as said polymeric film material emerges from said die,

A process for preparing seamless, creaseless, pliable, thin-walled tubes comprising extruding a continuous moving tube of polymeric film material from a die into the ambient atmosphere, radially stretching said continuous tube over a sizing disk as said polymeric film material emerges from said die, maintaining a pillow of pressurizing air within said tube in the region between said die and said sizing disk, longitudinally stretching said tube, maintaining the downstream free end of said tube open to the ambient atmosphere and free of creases, and severing said tube while maintaining the cross-sectional shape of said tube free of creases and while said tube is in motion thereby forming at least one tube segment having a right cylinder configuration substantially free of creases. Apparatus for preparing seamless, creaseless, pliable, thin-walled tubes comprising means to extrude a moving continuous tube of molten polymeric film material from a die into the ambient atmosphere, means to radially stretch said continuous tube as it emerges from said die, a disc shaped sizing means supported by said die, said disc shaped sizing means having a continuous outer circumferential periphery adapted to contact the interior of said tube and form an air pillow in cooperation with said tube and said die, means to introduce a fluid under pressure through said die into said air pillow, and means to longitudinally stretch said tube while maintaining the downstream free end of said tube open to the ambient atmosphere and free of creases, and means to sever said tube while said tube is in motion to form tube segments while maintaining said tube substantially free of creases.