Process for manufacturing a plastic hollow body, device and equipment for the implementation thereof

A process for manufacturing a plastic hollow body, said process comprising the following steps:

• extruding a tubular stream of molten plastic;
• inserting a tensioning device inside the tubular stream in order to flatten the tubular stream and to apply a force to the tubular stream in a substantially radial direction;
• tensioning the tubular stream with the tensioning device to subject the tubular stream to the force exerted from the inside of the tubular stream towards an outside of the tubular stream in the substantially radial direction at two diametrically opposed points, when the tubular stream is put under tension, the tensioning device including two stretching pins that move relative to one another to apply the force to an inner wall of the tubular stream at the two diametrically opposed points by moving the stretching pins away from one another;
• cutting the tubular stream transversely so as to create a parison having one free edge that is not taken up by the tensioning device;
• moving the parison relative to the tensioning device so that the free edge of the parison is taken up by the tensioning device;
• and
• cutting at least one longitudinal cut in the parison over an entire length of the parison,
• wherein at least one longitudinal-cutting device attached to the tensioning device splits the parison into two sheets,
• wherein the tensioning device includes a gripping device that grips the parison obtained by transversely cutting the tubular stream, and
• wherein the gripping device is inserted inside the parison prior to the parison being cut over the entire length and enables the parison to move relative to the tensioning device.