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Hohe Kosten für die Reinigung von Maschinen und Anlagen führen zu Bestrebungen, diese hinsichtlich Reinigungszeit und ‐flüssigkeitseinsatz zu optimieren. Ein Ansatz ist die Anwendung diskontinuierlicher Flüssigkeitsstrahlen. Hierfür wurden zwei Strömungsarten hinsichtlich ihrer effizienzsteigernden Wirkung für zwei Lebensmittelbestandteile Xanthan und Stärke untersucht. Im Ergebnis konnte der Reinigungsflüssigkeitsverbrauch für einzelne Betriebspunkte um die Hälfte gesenkt werden. Die Reinigungszeit sank bei der Xanthanverschmutzung ebenfalls, wohingegen sie bei Stärke gleich oder höher war.

The visual and mechanical quality of paperboard packaging components formed by deep drawing closely corresponds to the wrinkle distribution within the material wall section. Assessing this quality of paperboard packaging components currently relies on very slow or even subjective methods. Therefore, counting the number of wrinkles and measuring the mean distance between wrinkles proved to be a sensitive strategy for the evaluation of quality levels in deep drawing formed paperboard containers like cups or trays. A method introduced by Hauptmann proposes the measurement of the distances between 10 wrinkles in machine direction and 10 wrinkles in cross direction for each sample. However, this method is unsatisfactory because it can only observe a small part of each sample and is subject to deviation through the individual judgement of the person carrying out the survey. Further methods, as well as their respective application range, are listed in Table 1. Hence, it is desirable to automate the wrinkle survey to be carried out without operator influences to the measurement. This paper introduces such an automated measuring method. The given method relies on recording the sample surface topography through laser-distance measurement. An evaluation algorithm, which enables the detection of wrinkles in the topographic data, is proposed. Furthermore, it is shown that the method yields feasible results and is capable of generating reliable quality information in considerably reduced time frames. Copyright © 2017 John Wiley & Sons, Ltd.

The deep-drawing process of paperboard has experienced essential improvement in the recent past; however, the technological advancements have not been transferred to packaging machines yet. Two of the most important issues with regard to the reliable production of high quality 3D shapes are the use of elevated moisture and defined blank holder force profiles. This paper examines a roll preparation method for applying additional water to the paperboard and analyses a spring-loaded blank holder solution with regard to its achieved accuracy and reliability of the force characteristics. A two-sided roll application of water on the paperboard using a sponge rubber cover on one of the rolls produces a water intake of up to 12%. The effect of moisture applied by roll preparation is higher compared to conditioning under controlled climate conditions, and the preparation time is reduced to a few seconds. The spring-loaded blank holder introduced in the paper completely works in position control and avoids the switch over to force control as well as the problem of small position steps, which were necessary during force control. A harmonic oscillation of the blank holder while the material is drawn out of it could not be observed up to an output of 150 cycles per minute. An application of a roll-based moisturization unit and a spring-loaded blank holder force in modern packaging machines appears feasible and favourable according to the results of this paper and maintains the capabilities of this 3D forming technology to a large part. Copyright © 2016 John Wiley & Sons, Ltd.

The underlying paper examines the material behaviour of paperboard during three-dimensional forming, especially deep drawing with concave shape elements in the base geometry of the bottom. Therefore, a parametric geometrical description of the concave section is established. Experimental investigations to the material displacement and to appearing wrinkles and fractures at the wall of the samples related to stepwise increasing levels of the concave geometry prove a proposed material displacement theory as well as the hypothesis that material overflow from convex sections is delivered into concave sections. Secant length and concave radius turn out to be of significant influence for the load that is applied to the material. Paperboard early reaches its maximum strain at break in concave sections and thereby should reveal close limits for concave shapes. However, a considerable concave level can be formed without structural damage of the material. Furthermore, the investigations show that there are possibilities to support the strain conditions in the concave section. Copyright © 2014 John Wiley & Sons, Ltd.

Optimization of the quality of deep-drawn cups requires methods for precise measuring of quality criteria. This paper presents new objective methods to describe the quality of deep-drawn packaging components made of paperboard. The state of the art for quality analysis in three-dimensional paperboard forming is presented. Methods for the analysis of visual quality using image analysis and for the analysis of shape accuracy using surface scans are developed. Experimental results are used for the verification of the methods and for the investigation of influences of main process parameters. The new methods are found to be both precise and objective. A large blankholder force has been shown to cause an increasing number of wrinkles and has a negative influence on the shape accuracy. A high die temperature also increases the number of wrinkles but enhances the shape accuracy. The punch temperature has no effect on the number of wrinkles, but high punch temperature has a significant and positive effect on the shape accuracy. Copyright © 2014 John Wiley & Sons, Ltd.

Die Reduzierung des Ressourcenaufwandes fur Reinigungen in der Lebensmittelproduktion ist okonomisch und okologisch sinnvoll. Deshalb wird hier durch die Identifikation relevanter Verfahrensparameter das Potenzial der pulsierenden Spritzreinigung zur Steigerung der zeitbezogenen Reinigungseffizienz aufgezeigt. Der Einfluss der Frequenz sowie der relativen Einschaltdauer bei variiertem Volumenstrom wurde untersucht und ein signifikanter Einfluss der relativen Einschaltdauer nachgewiesen. Mit geeigneten Pulsationsparametern sind erhebliche Einsparungen von Reinigungsflussigkeit moglich. The reduction of resources needed for cleaning in food processing plants is economically and ecologically sensible. In this paper, the potential of the pulsating jet cleaning to increase the time-based cleaning efficiency is demonstrated through the identification of relevant process parameters. The influence of the frequency as well as of the duty cycle was studied at varied flow rate on a model soil, and a significant effect of the duty cycle has been demonstrated. With suitable pulsation parameters substantial savings of cleaning fluid are possible.

Paper and paperboard are widely used in various types of packaging. Paper-based packaging is a recyclable, biodegradable, renewable and sustainable product, which gives it certain advantages over most plastic-based packaging materials. Although paper-based packaging, in some areas, lacks attractiveness in terms of visual appearance, 3D forming is an important method for producing advanced shapes from paper and paperboard, suitable, for instance, for modified atmosphere packaging. That said, very little is known about the deformations experienced by paper-based materials in 3D forming. Understanding the role played by the mechanical properties of paper and paperboard in the 3D forming process is key to improving performance. This paper presents experimental results obtained using three different forming devices designed to be used with paper-based materials and links the formability data with specific mechanical properties of the paperboard samples. Paperboard properties that were found to correlate with formability were as follows: compressive strength and strain, tensile strain, paper-to-metal friction and out-of-plane stiffness. The requirements for formability are different for the fixed blank forming process and sliding blank forming process. Copyright © 2013 John Wiley & Sons, Ltd.

The ultrasonic sealing (USS) is a new and modern possibility to seal peel films for packaging, for example for food and for medical packages. The heat conductive sealing (HCS) in contrast is already well described in science and practice. This study is a comparison of the effectiveness of both the USS and the HCS method using low-density polyethylene/isotactic polybutene-1 peel films. The influence of the recipe of the film, i.e., the amount of the peel component used and the thickness of the peel layer, as well as the sealing parameters, i.e., the sealing temperature, time, and pressure in case of HCS and the sealing force, time, and amplitude in case of USS, on the peel behavior were investigated. To characterize the peel behavior, the peel force, the maximum peel force, and the fracture mechanics, energy release rate were used. The sealing force has a strong impact on the peel properties. This behavior is similar to the influence of the sealing temperature. The peel behavior can be adjusted by varying the content of isotactic polybutene-1. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

The closure process for packaging is a key process. It ensures the protective function of packaging and assures the packaged goods a long life. In this context, efficient and reliable sealing processes are essential for the production of sustainable packages. In this paper, several characteristics of the ultrasonic sealing process will be discussed and accompanied by experimental results. The introduction provides an insight into the ultrasonic sealing process, its heating mechanisms and the process steps. A comparison is made with conduction sealing. Furthermore, basic principles of heating and energy dissipation are related to the influences of the sealing parameters on the seam strength. The experimental studies were carried out on typical packaging films, such as polyamide-polyethylene laminates. The seam strength in ultrasonic sealing is compared with that in conductive sealing. A lower seam strength was found for ultrasonic sealing in all the tested films. Furthermore, the sealing behaviour of the packaging films contaminated with different kinds of foods was analysed for both sealing methods. Although the ultrasonic sealing method has marginal advantages for bulk materials such as wheat flour, conduction sealing was shown to be better for other products. A comparison of the energy consumption during the ultrasonic and conduction sealing verified the advantages of ultrasonic sealing. In particular for thick packaging films, the amount of energy required for bonding is significantly lower than for conduction sealing. In summary, this paper provides a survey of the characteristics of the ultrasonic sealing method in packaging applications – its advantages and limitations. Copyright © 2011 John Wiley & Sons, Ltd.

SUMMARY Three-dimensional forming is a key technology for the application of sustainable materials, like paperboard, in packaging technology. Until now, deep drawing is not considered as a suitable process for manufacturing of packaging components with advanced geometrical design because of the sensitive process and a large number of failure mechanisms. To better understand and apply the physics of deep drawing, the process was studied by experimental investigations. Therefore, an evaluation strategy for formed parts was developed to describe their quality by measurable values. The influence of the technological parameters temperature configuration, moisture content of material and blank holder force on the quality of formed parts was described by a statistic regression model. This model gives an indication of the quantity and the direction of effects that parameter changes have on the quality of 3D-formed parts. An optimization of the process according to quality criteria showed that, in a first step, the quality of cylindrically drawn paperboard parts was increased drastically compared with that of the state of the art. Furthermore, the existing limits in the height of formed parts were exceeded, and the geometrical shape of the base offered far more opportunities for packaging design than expected. The process turned out to be suitable for a flexible manufacturing of packaging components for multipart packages from paperboard, which are highly sustainable in terms of recycling and reuse of fibres and thereby able to compete in the marketing-oriented packaging sector. Copyright © 2011 John Wiley & Sons, Ltd.