초록 ▼

The process serves the purpose of producing containers. A heated pre-form made of a thermoplastic material is stretched and inflated with the aid of a gas under pressure for purposes of molding the container. The inflating process is divided into a preliminary blowing period with a gas under a lower

The process serves the purpose of producing containers. A heated pre-form made of a thermoplastic material is stretched and inflated with the aid of a gas under pressure for purposes of molding the container. The inflating process is divided into a preliminary blowing period with a gas under a lower level of pressure and into a subsequent primary blowing period with a gas under a higher pressure level. The ratio of the container diameter to the inner diameter is selected to be greater than 4.0. The pre-form has a median wall thickness of greater than 3 millimeters and at least at the beginning of the preliminary blowing phase is provided with a material temperature greater than 70 degrees Celsius. The pre-form at least at the beginning of the preliminary blowing phase in the area to be oriented is provided in the area of its upper surface with a temperature which is at a maximum equal to a medium temperature of the inner surface of the pre-form in the area to be oriented. The temporal duration of the preliminary blowing phase is selected to be less than 1.0 second. During the preliminary blowing phase the pre-form is expanded to at least 50 percent of the volume intended for the finished blown container.

대표청구항 ▼

[ What is claimed is:] [1.] A process for producing containers, in which a heated pre-form made of a thermoplastic material is stretched and is inflated by means of a gas under pressure and an inflation sequence is divided into a preliminary blowing phase with a gas under a lower level of pressure a

[ What is claimed is:] [1.] A process for producing containers, in which a heated pre-form made of a thermoplastic material is stretched and is inflated by means of a gas under pressure and an inflation sequence is divided into a preliminary blowing phase with a gas under a lower level of pressure and a subsequent primary blowing phase with a gas under a higher level of pressure, characterized by the fact that the ratio of the container diameter (23) to the inner diameter (20) of the pre-form (1) is selected to be more than 5.0, that the pre-form (1) has a median wall thickness (18) of more than 4 millimeters, that at least at the beginning of the preliminary blowing phase a material temperature of the area to be stretched is between 85 and 100 degrees Celsius, that the pre-form, at least at the beginning of the preliminary blowing phase in the area to be stretched has an outer surface temperature which at the maximum is equal to an inner surface temperature, that the temporal duration of the preliminary blowing phase is selected to be less than 0.5 seconds, that during the preliminary blowing phase the pre-form (1) is expanded to at least 60 percent of the volume intended for the finished container (13), that the pre-form is stretched at a stretching speed greater than 0.8 meter per second and that the finished blown container has a crystallinity greater than 30% and wherein a form stop working against the release of power of the compressed gases is provided to avoid contour deviations in the container (13) in the area of a blowing station (33) provided for shaping the container.