PET preform inspection system

IntraVis Vision Systems of Germany has installed its Sample PreWatcher machinery in the Coca-Cola plant in Halle, Germany, and into two large suppliers for Coca-Cola in the USA.

The Sample PreWatcher is a detailed inspection machine for preforms. It is placed directly behind high-performance injection preform machines, and it randomly analyses the quality of newly produced preforms. The Sample PreWatcher inspects the geometric preform characteristics, including measuring the length, diameter and wall thickness. It also inspects for ovality, form changes and material errors, and identifies cavity numbers for alarm monitoring for repetitive faults. It has a speed of 20 preforms/min.

Through rotation and multiple pictures a 360° view of the preform is generated, and the smallest contamination can be detected including colour variations. The machine also examines for irregularities at the injection point and checks the neck finish for scratches, notches and diameter irregularities.

The continuous batch QA sampling ensures high productivity, particularly with high cavitation (144 cavity) fast cycle systems that produce 50,000+ preforms/h. Conventional manual QA usually takes 1-2 h and therefore has the potential to send 100,000 preforms to scrap due to the time delay in checking and identification.

Reiner Roller, Regional Product Director for Coca-Cola, Halle, said, “The Sample PreWatcher is exceptionally easy to operate and its capability to recognise and reject faulty preforms is very reliable and efficient.”