Method for manufacturing a thermoplastic container and system for pulling a tube apart

Method for manufacturing a thermoplastic container, the method comprising:

• a) providing a thermoplastic tube with an inner wall, an outer wall, a longitudinal direction, a first end, a second end, a middle zone, a first zone and a second zone, the first zone extending from the middle zone to said first end and the second zone extending from the middle zone to said second end;
• b) gripping said first zone and said second zone;
• c) locally heating said middle zone to the thermoforming temperature of the thermoplastic;
• d) pulling said first zone and said second zone apart along said longitudinal direction thereby narrowing the middle zone;
• e) closing a closing portion of the middle zone to obtain a closure;
• f) cutting the closed-off middle zone at the location of the closing portion to obtain two separate tubular parts;
• and
• g-iv) deforming at least one of said tubular parts into a container,
• wherein step b) comprises gripping said first zone and said second zone with the aid of retaining members, each of said retaining members having a mould surface which is substantially perpendicular to said longitudinal direction and is located along said middle zone,
• wherein step d) comprises pulling said first zone and said second zone apart along said longitudinal direction thereby narrowing the middle zone by moving said retaining members away from each other,
• wherein step f) comprises cutting through the closed-off middle zone at the location of the closing portion to split the middle zone into a first portion and a second portion so that said tube is split into a first and a second tubular part, the first tubular part comprising said first zone and a first bottom portion, which first bottom portion is formed by said first portion of the middle zone and the second tubular part comprising said second zone and a second bottom portion, which second bottom portion is formed by said second portion of the middle zone, and wherein step g-iv) comprises:
• g-i) arranging, for at least the first tubular part, a bottom moulding member opposite a respective one of said retaining members such that said first bottom portion is located between the bottom moulding member and the respective retaining member, each bottom moulding member being provided with a counter mould surface which is substantially perpendicular to said longitudinal direction and is oriented towards its respective mould surface;
• and
• h-i) deforming said first bottom portion into a bottom by pressing the bottom moulding member and its respective retaining member against each other.

Method for manufacturing a thermoplastic container, the method comprising:

• a) providing a thermoplastic tube with an inner wall, an outer wall, a longitudinal direction, a first end, a second end, a middle zone, a first zone and a second zone, the first zone extending from the middle zone to said first end and the second zone extending from the middle zone to said second end;
• b) gripping said first zone and said second zone;
• c) locally heating said middle zone to the thermoforming temperature of the thermoplastic;
• d) pulling said first zone and said second zone apart along said longitudinal direction thereby narrowing the middle zone;
• e) closing a closing portion of the middle zone to obtain a closure;
• f) cutting the closed-off middle zone at the location of the closing portion to obtain two separate tubular parts;
• and
• g-iv) deforming at least one of said tubular parts into a container, wherein step g-iv) comprises:
• g-ii) placing at least one of the tubular parts in a mould;
• h-ii) heating said tubular part in the mould to the thermoforming temperature of the thermoplastic;
• and
• i-ii) deforming said tubular part against the mould to obtain said container.

Method for manufacturing a thermoplastic container, the method comprising:

• a) providing a thermoplastic tube with an inner wall, an outer wall, a longitudinal direction, a first end, a second end, a middle zone, a first zone and a second zone, the first zone extending from the middle zone to said first end and the second zone extending from the middle zone to said second end;
• b) gripping said first zone and said second zone;
• c) locally heating said middle zone to the thermoforming temperature of the thermoplastic;
• d) pulling said first zone and said second zone apart along said longitudinal direction thereby narrowing the middle zone;
• e) closing a closing portion of the middle zone to obtain a closure;
• f) cutting the closed-off middle zone at the location of the closing portion to obtain two separate tubular parts;
• and
• g-iv) deforming at least one of said tubular parts into a container,
• wherein step b) comprises gripping said first zone and said second zone with the aid of retaining members, each of said retaining members having a mould surface which is substantially perpendicular to said longitudinal direction and is located along said middle zone,
• wherein step d) comprises pulling said first zone and said second zone apart along said longitudinal direction thereby narrowing the middle zone by moving said retaining members away from each other,
• wherein step f) comprises cutting through the closed-off middle zone at the location of the closing portion to split the middle zone into a first portion and a second portion so that said tube is split into a first and a second tubular part, the first tubular part comprising said first zone and a first bottom portion, which first bottom portion is formed by said first portion of the middle zone and the second tubular part comprising said second zone and a second bottom portion, which second bottom portion is formed by said second portion of the middle zone, and
• wherein step g-iv) comprises:
• g-iii) for at least the first tubular part, sucking gas away from a space between said mould surface and said first bottom portion for the purpose of deforming said first bottom portion until it abuts said mould surface.