Hans Riegelein GmbH & Co. KG is one of Europe's market leaders in chocolate figures. Its factory in Cadolzburg produces a huge range of seasonal and year-round products, which are exported to many parts of the world. Over 10,000 tonnes of chocolate are produced each year and consumed on countless occasions.
As part of its quality assurance process, Hans Riegelein defined several control points. These were to be equipped with foreign object detection systems. Depending on the inspection point, metal detectors and X-ray systems were used to meet the requirements.
As the customer's process and the defined installation locations required highly individual solutions in some cases, we were able to bring our strengths to bear and convince our customers of the benefits of tailor-made foreign object detection and ejection systems.
L-conveyor with integrated metal detector for chopped nuts
An L-conveyor with integrated metal detector was manufactured for the inspection of loose, chopped and unpackaged nuts.
The products are transferred via a filling hopper. The nuts are placed in this hopper by the operating personnel and the product flow is adjusted via an adjustable outlet to ensure optimum loading of the conveyor belt.
The products are then conveyed to a delivery height of 1,500 mm. At the end of the ascending belt, the nuts are fed into a customer-supplied hopper for further processing.
Products contaminated with foreign objects must not enter the hopper. During transport, the product is therefore checked by a metal detector integrated into the conveyor belt. If metal contamination is detected, the product is ejected by a pneumatic flap. This diverts the product flow and directs the nuts into the collection container via a chute.
As the nuts are allergens, the system should be equipped with cover hoods and collection trays as far as possible. These ensure that transfer to other production areas is avoided as far as possible. To ensure that the system can be cleaned, the cover hoods and collection trays have inspection flaps and allow easy, tool-free assembly and disassembly.
Detection system for flat chocolate figures
Another application implemented in this project is a metal detector for inspecting flat chocolate figures.
These are conveyed in multiple rows on plastic trays and must be checked for foreign objects before packaging.
The conveyor unit of the metal detector was customised so that the trays are transported on two narrow belts. If metallic foreign objects are detected, an ejection unit located above the conveyor belt ensures that the chocolate figures are deflected towards the centre and fall down into a collection container located below. This saves space in production and ensures safe ejection without ejecting the plastic trays.
Inclined conveyor with detection coil for chocolate balls
Another metal detector has been integrated into an inclined conveyor to check chocolate balls.
The products are transferred via a customer-side conveyor belt. The chocolate balls are continuously transferred from this belt.
The products are then conveyed to a delivery height of 1,300 mm. At the end of the ascending belt, the chocolate balls are fed into a customer-supplied collection box for further processing.
Products contaminated with foreign objects must not enter the collection box. During transport, they are therefore checked by a metal detector integrated into the conveyor. If metal contamination is detected, the product is ejected by a pneumatic flap. This diverts the product flow and directs the chocolate balls into the collection container via a chute.
X-ray for checking hollow chocolate shells
Another control point concerns the inspection of hollow chocolate shells.
These are wrapped in metallised foil during packaging, which rules out inspection using a metal detector. In order to ensure product safety nonetheless, the company has invested in future-proof X-ray technology.
The installed X-ray system checks three parallel lanes simultaneously to see if any of the hollow figures contain foreign objects. If such an object is found, it is ejected by means of a return belt. Contaminated products then fall into a collection container located under the conveyor belt, while chocolate figures that have been given a positive rating are sent to the final packaging stage.
As an added bonus, the X-ray system not only detects metallic foreign objects, but also finds non-metallic contaminants such as glass, thereby increasing product safety.
Metal detection system for broken goods
Another metal detection system was required to check broken goods.
The broken chocolate shells are manually tipped onto a conveyor belt as bulk material. This creates a continuous product flow, which is to be checked for contamination with metallic foreign objects by the metal detector.
If metals are detected, they are ejected via a flap belt. When a foreign object is detected, this swings upwards, creating an opening between the two conveyor belts. The contaminated products fall into a collection container mounted below the conveyor belt. Uncontaminated products are transferred to the customer's discharge system.
After-sales service
In addition to the installation of the systems and training of personnel, the complete package also includes after-sales service in the form of scale maintenance. This minimises downtime and optimises product longevity.
Conclusion
Depending on the location, we were able to support Hans Riegelein with metal detection and ejection systems that were perfectly adapted to the location.
All metal detectors work with modern multi-frequency technology, ensuring highly accurate detection of metallic foreign objects in unpackaged products, while the X-ray system checks hollow objects already packaged in metallised film for contamination.
The installed foreign object detection systems were all integrated into Hans Riegelein's production process as desired.
The partly highly individual ejection systems ensure the safe ejection of detected contamination and also reduce waste.
This means that the production chain is reliably checked from the raw material to the finished end product.
Sascha Wolff
Technical Product & Business
Development Manager
Phone: +49 5401 4977 41
Mobile: +49 160 90593515
s.wolff(at)hoefelmeyer.de
