Stretch rod for inflating a preform

A method for blowing a heated preform into a container, comprising:

• inserting a stretch rod into the heated preform until the bottom of the stretch rod directly contacts a curved, semi-spherical end portion of the preform;
• as the stretch rod is inserted, stretching the preform to its container length until the preform touches a base of a blow mold in which the preform is encompassed;
• directing compressed air through a first plurality of apertures of the stretch rod in a handle pocket zone, between an upper attachment point and a lower attachment point of an integral handle of the preform, forming a shelf of the container;
• and
• directing compressed air through a second plurality of apertures of the stretch rod in an optional zone disposed below the handle pocket zone, forming a remainder of the container from the preform.

A method for blowing a preform into a container, comprising:

• heating the preform to obtain a heated preform;
• inserting the preform into a blow mold and closing the blow mold such that the blow mold encompasses the preform;
• inserting a stretch rod into the heated preform until the bottom of the stretch rod directly contacts a curved, semi-spherical end portion of the preform;
• as the stretch rod is inserted, stretching the preform until the preform touches a base of the blow mold;
• directing low pressure air, in a preblow cycle, through a blow nozzle that seals the heated preform;
• and
• directing high pressure compressed air through a plurality of apertures arranged on the stretch rod to obtain a blown container,
• wherein the plurality of apertures are arranged uniformly in two regions of the stretch rod, wherein a first subset of the plurality of apertures are shaped as slots and located in a handle pocket zone of the preform, and a second subset of the plurality of apertures are circular holes located in the optional zone below the handle pocket zone of the preform.

An apparatus comprising:

• a heated preform;
• a blow mold for receiving the heated preform;
• a blow nozzle for sealing the heated preform in the blow mold;
• and
• a stretch rod comprising:
• a hollow, cylindrical body that is made of metal;
• and a first plurality of apertures arranged on the body of the stretch rod,
• wherein compressed air is blown through the first plurality of apertures to form a blown container,
• wherein the body of the stretch rod comprises a handle pocket zone with the first plurality of apertures and an optional zone disposed on the stretch rod below the handle pocket zone, the optional zone comprising a second plurality of apertures, wherein the compressed air is blown through the first plurality of apertures and the second plurality of apertures simultaneously.