Production quality and uniformity in manufacturing and processing is closely related to good Quality Control (QC) during the manufacturing process. On-line systems are capable of delivering solutions for QC monitoring.
In particular this technical note deals with optical quality control, for raw materials or final products used in pellet or free flowing powder form, or for sheets and films of various opaque, semitransparent and transparent materials. These online systems are based on optical closed circuit cameras, and are used to observe the powder/pellets or film/sheet. Comprehensive software can analyse the images, recognising and cataloguing user-defined abnormalities, complete with images, sizes and user defined classifications, including tears, scratches, holes, discolourations, as well as dimensional irregularities for pellets and so on. The system can be trained to recognise and catalogue any defect seen by the camera, and the camera can be used in either transmission mode (for transparent films) or reflection mode (for opaque films, or a combination of both).
These on-line systems provide streamlined data, showing changes in important QC criteria for the product during the process. In this way corrective action can be quickly taken, minimising potential for waste and reprocessing.
On-line optical QC
The optical properties of many materials are a crucial indication of their quality. Optical properties of raw materials like granules or powders can be important in dictating the quality of the materials they are used to manufacture. Any discolouration, dimensional irregularities or contamination can adversely impact on the quality of the manufactured product. On-line analysis of some, or all, of the pellet or powder stream for these defects can prevent poor quality product entering the manufacturing process, and reduce the wastage therein. On-line CCD camera systems with high performance computers and software are becoming increasingly important in the recognition, recording and removal of these impurities before they can harm the product or the reputation of the manufacturer.
Once a sheet or film of product has been formed, it is important that it is of high quality with low levels of impurities (eg. insects), discolourations (fish eyes, black spots etc), pinholes, tears, surface defects etc. Poor quality control in these areas can lead to customer returns, dissatisfaction and reduced shelf-life of the product. Using CCD technology, along with sophisticated image processing and analysis software, the quality of a film or sheet can be continuously monitored and impurities detected. The size, colour and shape of the impurities which are important can be defined by the user.
Optical Control Systems gmbh (OCS) manufacture cutting edge optical QC equipment for pellets, powders, films and sheets for manufacturing industries.
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