Real time production process control

When working with preforms, bottles, or plastic sheeting, the thickness can be precisely monitored during manufacturing to optimize the process and improve throughput. Deviations in the production process are recognized by the non-contact measurement of the CHRocodile. The high measuring speed makes it possible to use during production. CHRocodile sensors have also been used for topography measurement of injection molds, wall strength measurement of blisters (PET, PP, EVOH), and bottle thickness with well-known manufacturers.

CHRocodile K
Non-destructive measuring of plastic welded seams

Welded seams in plastics must often undergo non-destructive tests. This may be the case in medical applications, such as multi-chamber pouches. Also the connection between the pouch and hoses and connectors can also be joined with welded seams. Quality and reproducibility can also be tested by the thickness of the welded seam.

CHRocodile LR
Measuring air gaps and film thicknesses in production processes of technical polymers and PET

Technical polymers, such as Cyclo-Olefin-Copolymers (COC), are amorphous and therefore transparent, unlike partially crystalline polyolefins. As a result, they are particularly suitable for unilateral, contact-free thickness measurements by optical sensors. Low twin refraction properties are important for optical applications. Outstanding biocompatibility and extremely low water absorption/ water vapour permeability must be emphasised in the field of medicine and diagnostics. COC products are optical window films for flat screens as well as syringes, microtitre plates, cuvettes and flasks. In production, Precitec sensors measure the thickness of air gaps and layer thicknesses.

CHRocodile sensors are also used in coating processes by polymethyl methacrylate (PMMA, acrylic glass or Plexiglas). They can also be used in inline processes (roll to roll) to measure layer thicknesses (in the low micron range) on Polyethylenterephthalat (PET), unlike sensors with a low sampling frequency. 

CHRocodile S / SE
Measuring the thickness of plastics or plastic coatings

Polycarbonates are coated to increase scratch resistance or UV resistance, for example. The coating and the material thickness can be measured by optical sensors without the sensors coming into contact with the items. Polycarbonate, a transparent plastic, is often used as an alternative to glass. Compared with brittle glass, polycarbonate is lighter and considerably more shock-resistant. Its negative properties, such as scratch-resistance or UV resistance can be reduced by coatings. For example, polyurethane acrylate layers of a few microns can be measured with the CHRocodile SE sensor.

The same also applies to EPDM. This is ethylene proplylene diene monomer rubber (cellular rubber). It is used for various seals, such as O rings for slide ring seals and for hoses, for steam or hot water, because it is highly flexible and has good chemical resistance. A confocal sensor can detect undesirable corrugation in the material. 

CHRocodile IT TW
Measuring layer thicknesses of food packaging films

Multiple layers can be measured by the CHRocodile IT-TW using interferometric thickness measurements with infrared light. This is the case, for example, with multi-layer food packaging films where the adhesive layer thickness is important. Places without adhesive can be detected in this way. In this way the thickness of films that are not transparent to white light can be measured. Even the individual layer thicknesses of multi-layer films can be measured if the refractive index of the materials is different.

CHRocodile K
Inline wall thickness measurement of artificial casings

The product to be measured is an artificial casing made of collagen. This is used as a natural skin for sausages. The material has a rough surface. This is made from a by-product of leather production and is known as a hide fibre sleeve. Here the ability of the measuring system to transfer continuous measurements to the measuring head quickly and therefore to measure strongly vibrating films is impressive. Without this measuring option the measurements must be taken using a much more inaccurate tactile process by determining the weight. This is much slower. The CHRocodile K sensor supplies high quality thickness values with this semi-transparent film that appears uneven and full of fissures according to the measurement results.

CHRocodile K
Measuring the wall thickness of plastic moulded parts

Plastic moulded parts, such as cuvettes or pipettes, can be measured without contact with an interferometric measuring system. Wall thicknesses can be determined in this case directly with the optical probe and a spacer on their own if no measuring machine is available.

CHRocodile S / SE
Topography measurements on injection molded parts

Injection molded parts can vary in nature - whether it concerns form, color or surface condition. A topography measuring system needs to work well with these basic conditions, but should also provide values that make sense to the user. The CHRocodile SE in connection with high aperture optical measuring heads work together to fulfill these requirements. The measurements can be applied to all surfaces, suitable for almost all component geometries and are not sensitive to environmental influences. The measuring precision and lateral resolution are in the µm range, axial resolution in the sub µm range. CHRocodile sensors are able to take high speed measurements, and with the synchronization capabilities to match industry standard interfacing, it is possible to characterize large samples quickly and efficiently.

CHRocodile K
Thickness measurement of thin plastic

Thin transparent and non-transparent films are typically produced at high speeds, under demanding conditions. Because of this, a more robust sensor must be utilized to determine the film thickness during production. The measurement technique can not be affected by environmental parameters such as temperature, humidity, or vibration of the film. The CHRocodile K, with its interferometric measurement method, meets these conditions perfectly - all while combining the highest precision and speed. This allows the process parameters of film production to be controlled with minimal latency.

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