SURFACE MASTER-BREAKING THE LIMITS OF ALUMINIUM SURFACE INSPECTION

SURFACE MASTER-BREAKING THE LIMITS OF ALUMINIUM SURFACE INSPECTION SURFACE MASTER DEFINES INSPECTION PERFORMANCE IN A NEW WAY

INSPECTION PERFORMANCE = PERCENTAGE OF CORRECT QUALITY DECISIONS Increased customer demands and a competitive market in today’s aluminium strip production have made it critical to continuously work on improving efficiency in the manufacturing process and the overall quality of the final product.

Automatic surface inspection is the status quo in many production steps. SURFACE MASTER defines the top in terms of image acquisition and classification, but the key for the successful use of surface inspection systems is the inspection performance.

What does inspection performance mean? Even the best images will not help improving the process or making precise quality decisions without a system selecting the relevant information from the huge amount of data. Beside proper detection of surface defects, classification is the key to the most important step: creating data quality. SURFACE MASTER filters and aggregates the defect information to support your decisions in process optimization, material grading and downstream optimisation.

Inspection Performance The goal using surface inspection systems is creating the base for confident quality decisions.

The major aspect to allow this is Inspection Performance that means getting exactly the data which is needed for the decision.

This includes sharpest images, confident detection and exact classification of the relevant defects.

It starts with image acquisition: The broad experience of ISRA VISION PARSYTEC with all

kinds of production lines in the aluminium manufacturing process is condensed into a portfolio of SURFACE MASTER Sensor configurations, well adapted to the individual line types, thus providing optimum image acquisition during the aluminium manufacturing process. SURFACE MASTER guarantees highest resolutions, even on fast production lines by using the most advanced cameras.

For most complex inspection tasks on lines with a great variety of material – from bright to dark and from shiny to dull - the DUAL SENSOR™ creates best image quality by combining one sensor with diffuse illumination and one sensor with direct light.

The following figure illustrates the advantage of the combined approach.

differentiation at a classification rate far beyond what’s possible using just a single classifier and is the precondition to create data quality. It allows filtering the data according to the different tasks.

To protect a tension leveller, only information about holes and edge cracks is necessary. To inform the melt shop about quality problems regarding the casting, only nonmetallic inclusions may be relevant, whereas for process improvements, a lot of defects may be interesting.

Applications SURFACE MASTER’s outstanding inspection performance allows a variety of (semi-)automatic applications for immediate reaction on surface quality issues.

DUAL SENSOR™ : all 8 real defects

DUAL SENSOR™ unique with ISRA VISION PARSYTEC After detecting the defects within an image, it’s necessary to classify them according to the defect type and grade to prepare quality decisions. The hierarchical classifier approach using specialized classifiers, e.g. for shells or for scale, allows a

Tension Leveller Protection One example is ISRA VISION PARSYTEC’s Tension Leveller Protection. Tension levelling lines have to deal with strip breaks. The costs of strip breaks are high, taking time to get the mill up and running again, additional costs arise due to

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roll shop cost, material loss, and overall attention to this problem.

As strip breaks due to material defects often form the majority of strip breaks, eliminating those allows putting a clear focus on the operational issues. Based on the highest inspection performance, SURFACE MASTER offers a unique and innovative tension leveller or cold mill protection solution, scale perfectly applies to tension leveller in aluminium.

Severe surface defects can cause strip breaks in a tension levelling line, leading to loss of material and machine downtimes.

Identifying these defects in-time for immediate process reaction provides significant yields in terms of runability and throughput.

Harmful defect (hole) at a tension levelling line Ensuring Highest Quality Standards: Defect Marking (fig.1) Aluminium producers that are simultaneously supplier to further processing industries such as can manufacturers have been asked to physically mark defective strip areas .

This allows discharging marked areas of the strip in the end-users manufacturing process. Hence, the highest possible quality standard

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SURFACE INSPECTION

of the produced material can be assured.

During production, critical defects will be detected automatically for the marking process. Immediately after the recognition, the relevant defects can be marked. On top, if there is sufficient time between the defect recognition and the required action of marking, a review by the operator of the defects which are going to be marked can be additionally included in the procedure.

This overall process is based on a rule set which is defined and adjusted according to the requirements of each end-user.

This defect marking solution helps providing material of a constant high quality. The interactive approach supports the decision-making process of the inspector Automatic Sorting (fig.2) If the time for an inspector’s review is too short, there is also the possibility for fully automatic operation. One very effective application is the Automatic Sorting, e.g. for coated Litho sheets.

The strip is cut into sheets, but not all of those sheets are of the same high quality. Sorting the sheets automatically according to their quality can be enabled by an inspection system, specially trained for triggering this sorting process.

(fig.1) Defect Marking

Advanced System Characteristics To Create Benefits Inspection performance is the key for confident decisions but there are other characteristics making an inspections system breaking today`s limits.

Image Processing Power To get the best detection performance on high resolution images, even at highest speed, the inspection system needs sufficient Image Processing Power to precisely analyse each and every image taken from the surface. SURFACE MASTER allows adjusting this power exactly to the specific needs.

Fast Start-Up The best inspection system will not create benefit if the commissioning takes too long. SURFACE MASTER contains easy to use tools to setup the system in shortest time.

SURFACE MASTER comes with an instant classifier and pre-settings which allow starting the payback within one month.

Auditability Today’s customers are more and more interested in the used quality management. Your customer will trust you because SURFACE MASTER offers tools and reports for best auditability. This starts with a comprehensive system diagnosis and a long term analysis of the system performance and ends with a System Performance Indicator for each produced coil.

(fig.2) Automatic Sorting Process and Product Analysis SURFACE MASTER offers flexible reporting and analyzing tools for operators, quality engineers and controller. Examples are:

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Online view on the running coil and all defect images Coil reports to travel with the coil Width measurement report Web reports make the quality visible on the intranet Shift reports to examine the shift performance

Highest System Availability SURFACE MASTER is designed to guarantee 100% inspection. The system utilizes standard hardware that can be exchanged in shortest time. The cameras are pre-

calibrated, so that even a change can be done within shortest time.

For even higher availability redundancy packages are available.

Conclusion We can conclude that surface defects make surface inspection indispensable for each and every aluminium manufacturer. Surface Inspection Systems enable the detection of surface defects and thereby give the possibility to repair defects where possible or to eliminate their causes. To get the full benefit out of the surface inspection results, only the relevant information must be filtered out from the vast data. Hence, SURFACE MASTER with its outstanding inspection performance contributes to the enhancement of the produced material by reducing downtimes of the system due to fewer coil breaks, by producing less scrap and thus lowering the manufacturing costs, and by finally gaining high-quality aluminium. Surface inspection should be an integral part of the production process chain in the aluminium industry as it guarantees a high level of surface quality.

ISRA VISION PARSYTEC Auf der Hüls 183 52068 Aachen Germany

Superior Quality and Optimum Yield: SURFACE MASTER in Action

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