PROCESS CONTROL & CONFORMITY

The unique high sensitivity is connected with a limiting pixel resolution of 0.1 mm, which gives real-time X-ray images of an extraordinary quality. The production speed can reach 30 m/min (limit 200 m/min), and products can be sorted into different quality categories. A powerful PLC, connected to a powerful computer, manages the data processing in real-time. High-speed communication ensures the correct activation of the sorting mechanisms, via a series of I/O terminals. The number of quality categories to sort into are un-limited, yet the standard system has 10 I/O terminals for reject/sorting arrangements.

MAIN FEATURES

  • Optional conveyor width to 2000 mm
  • Multiple lane solutions
  • Production speed to 200 m/min
  • Detection down to 0.2 mm
  • Ultra high sensitivity
  • Sorting into different quality categories

Traditionally, X-ray technology is used as a final reject, especially for contaminants detection in the food sector. During the last years, InnospeXion has developed a unique real-time X-ray imaging technology, based on using a part of the X-ray spectrum not used in other X-ray imaging systems. At the same time, a substantially higher resolution (0.1 mm) and a very fast imaging speed has been achieved. This means that on-line X-ray images today may have an information content that enables the X-ray system to continuously measure and verify conformity of even very thin and very small details relevant for modern production. Thus, the InnospeXion X-ray systems may be used as on-line process control stations where significant product parameters are continuously measured, verified, and reported. The benefit is to enable a contingency action prior to deviations ending as faulty products.

APPLICATION AREAS

Bakery product X-ray inspection – biscuits & cakes process and product control

Objective

Modern manufacturing lines require a strict control of the correct distribution, dimensions, and mass of the dough, in addition to e.g. contamination inspection. High contrast X-ray imaging online enables the fast and reliable control of the product conformity before the baking process. This leads to immediate action-taking when there are issues with the performance of the dosage system. Consequently, downtime is largely eliminated and discard of non-conforming products is minimized.

Solution

The InnospeXion technology enables the compactness and robustness required to insert X-ray inspection during the forming process.

However, the X-ray technology also is applied to inspect the baked products and to secure that the products are packaged correctly, with the correct, uncontaminated, and un-damaged amounts in the package. This also gives additional value to the product and safeguards a minimum of recalls and customer complaints.

  • Tailored, ultra compact design
  • Ultrafast inspection capability: Line speed up to 180 m/min
  • Fast signaling cycle: Approx. 15 ms or better
  • High precision in marking of defect – better than 0.1 s precision (depending on local layout of network and control/handshake)
  • Robust
  • Detection capability 0.1 – 0.8 mm, speed dependent
  • Ultra high sensitivity – high contrast images
  • Suitable for multiple products in one system (multiple lines per system) (total width < 100 mm)
  • System product coverage 100 mm in width, optional larger width
  • 2 m distance (cable connection) between control compartment and inspection compartment
  • Standard off-the-shelf systems for contamination and product conformity inspection
Detection of contaminants in large cheese blocks

Objective

The distribution of voids and holes in cheese may have a large influence on the quality of the cheese. For certain cheese types, a void development may result in failure to sell the cheese. This concerns e.g. cheeses based on sheep milk and others, as well as other cheeses with a long maturity requirement. The problem is, that the voids may develop near the surface, causing fungi to enter the cheese cavity. This makes the cheese to develop as a blue cheese which impedes that it can be sold. Such void development may occur at any stage during the long maturation process, thereby causing significant waste and loss for the manufacturers.

The ability to scan the cheese at regular intervals may facilitate that the cheese can be sold when a hole is developing critically near the surface.

The objective was, therefore, to develop, test and install an X-ray system which can determine when the cheese is ready for the market.

Solution

Development, design, testing, and installation of a prototype high sensitivity and high-resolution tomographical scanning system suitable for the inspection of cheese.

Achievements:

A commercial tomographical X-ray system for cheese inspection with the following specifications:

  • Automatic in- and out-feeding of cheese and automatic scanning and decision-taking of critical hole development in cheese
  • High contrast, high resolution imaging with tailored X-ray scanning detector;
  • Operating at maximum 70 kV, at very high flux, and with large output stability
  • Lead-free radiation cabinet with integrated conveyor section
  • Software package for general assessment of cheese, automatic operation
  • System control and safety system complying to European and US regulations
  • Cycle time 1-4 cheeses/min
  • Hygienic design suitable for cheese producers
  • Automatic/semi-automatic decision taking and sorting

Modern food production is a well controlled process. However, occasionally deviations occur, and contamination of the cheese with plastics, rubber, steel and other materials is possible.

Traditional X-ray imaging may find application to detect larger foreign objects of high density, but present day requirement is a detection of defects down to 0.2 mm and detection also of light foreign objects, such as some plastics and rubber, as well as integrity assessment of the packaging.

The InnospeXion technology is a hygienically designed system for the on-line inspection of food products, with a dual focus: verifying the conformity of the product in the package (if any), and detection of foreign objects.

Fruit ripeness and seed sprout assessment using X-ray technology

 

The avocado inspection problem

The quality, price, and overall sales parameters for avocado and other fruits are related to their ripeness and damages that they may have suffered upon transport. Avocado is especially vulnerable to become overripe, a condition which may be difficult to distinguish from ripe fruits, and a condition which makes the fruit worthless.

The seed sprout problem

Expenses on care-taking of seeds with bad sprout capabilities and the cost of farm surfaces or forest land without crops are significant. Therefore, for some crops and types of seeds, the sprout capability assessment has a large value.

Solution

The low-energy X-ray scanning of e.g. avocado fruits can be accomplished with the fruit traveling past an X-ray scanner on a conveyor belt, separated into lanes. The speed of the belt is typically about 12 m/min (limit is 27 m/min), and the inspection speed is around 1 avocado per second for each lane or about 4 avocados per second at 12 m/min.

The X-ray images unveil that the ripe fruits correlate with a void development around the inner core, at the early stages of the ripe. Later, an uneven internal structure with cracks seems to correlate with the further ripe of the fruit, and this can also be correlated to a softer feel of the ripe avocado. A sorting mechanism based on the ripe condition and possible damages can be positioned immediately after the X-ray scanner. This sorting mechanism reacts on the basis of the real-time image processing and image quantification of the X-ray scanner.

For seed inspection, they typically are inspected relative to the internal structure, especially the internal density. The inspection may take place with the seeds positioned in a tray. Low density and large internal voids in the seed implies that the seed may not have the sufficient sprout capability, and therefore must be rejected. For some seeds, the proportion of not useful seeds may be substantial.

The low-energy X-ray scanning is a prerequisite for the cost-effective applications of ripe sorting and seed sprout sorting.

Glass splinters constitute a major problem in the production of food products packaged in glass jars, bottles, and containers. The splinters may have very hazardous consequences. X-ray technology has been used for years for the inspection of filled glass packaging with food products. The problem is, that the normal X-ray technology is inadequate for the revelation of critical glass splinters. This is due to the fact that the contrast between the glass pieces and the product inside the glass jar has to be relatively large in order for automated image analysis algorithms to detect and correctly reject a faulty product. In addition, the resolution of the image acquisition sensor has to be high in order for as many pixels as possible to represent a defect. Unfortunately, high resolution and high contrast are in contradiction. High resolution implies small pixels, and hence a small “count number” due to a very small detection area. This makes noise be relatively high compared to a (small) “count” difference between a defect and a neighbor area without a defect.

The high contrast, high-resolution imaging in the Royal Awarded  InnospeXion glass-in-glass detection system integrated with a novel, fast and very robust and reliable automatic glass splinter detection algorithm. This enables even the tiniest glass fragments to be detected, even when placed next to the glass wall.

This new X-ray technology pushes the detection level to the real need – to detect what is critical for the consumer. 

CASE STORY

We are still working on a case story for this application, which will be ready shortly. In the meantime, feel free to flick through our case story on fish bone detection.