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- Larsson, Joakim, 1989-
(författare)
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Have you heard about wire? Monitoring of the wire drawing process
- 2024
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Wire made from metal is a fundamental component found in almost every complex product, ranging from a simple pen to a spacecraft. It is used to manufacture nails, screws, springs, rivets, cables, welding electrodes, and numerous other items that surround us daily.In an era characterized by increased environmental concerns and the pressing need for the industry to become more sustainable, process monitoring has emerged as a key instrument for strengthening the sustainability improvements of diverse industries and operations. Many industries have transitioned into the realm of Industry 4.0, entering an era of digital transformation and datadriven decision-making. However, the production of steel wire has fallen behind. The wire drawing process has been performed in a similar manner for the last century and the production machines generally lack advanced monitoring systems. To catch up, there is a great need to digitize the wire drawing process and that is the focus of this thesis, Monitoring of the wire drawing process.In this thesis several different methods to monitor the wire drawing process are developed and evaluated, resulting in a process monitoring system for the wire drawing process.
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| 2. |
- Marin, Gustav
(författare)
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On the relation between paperboard properties and packaging performance
- 2020
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Paper-based materials, such as paperboard, are commonly used as packaging materials. Inaddition to the advantage that wood as a raw material is renewable, there are also many otherbenefits of paperboard. From a mechanical point of view, paperboard has a high bendingstiffness compared to its relatively low weight and has a high foldability, which both areproperties of significance in the design of packages. However, a distinct drawback withpaperboard is its significant sensitivity to moisture. The moisture reduces the mechanicalproperties of the paperboard and consequently reduces the performance of the package. Thisthesis is starting with an investigation of the relation between moisture and differentmechanical properties on a continuum material level, and then these relations are applied onthe packaging design level through experimental testing and simulations.In Paper A, a material characterization was performed on a series of five paperboards withdifferent grammages from the same producer. Five types of mechanical tests to characterizethe paperboards’ material properties were performed:• In-plane tensile test,• Out-of-plane tensile test,• Short-span Compression Test (SCT),• Bending stiffness test,• Double-notch shear test.All tests were performed at several levels of relative humidity (RH). Linear relations betweenthe mechanical properties normalized with their respective value at 50 % RH and moistureratio were found.Paper B examined whether the linear relationships discovered in Paper A are true also forother paperboard series as well. Therefore, 15 paperboards from four producers wereinvestigated in this study, at the same levels of RH as before. Here, the in-plane stiffnessesand strengths and SCT-values were evaluated as a function of moisture. When also themoisture ratios in the investigated paperboards were normalized, it turned out that allpaperboards followed the same linear relationship between normalized mechanical propertyand normalized moisture ratio. Additionally, a bilinear elastic-plastic in-plane model wasdeveloped, that can predict the stress-strain relation of an arbitrary paperboard at an arbitrarymoisture level, and without requiring any mechanical testing except at standard condition(50% RH, 23 °C).In Paper C, this relation was used to estimate input material parameters for simulating a BoxCompression Test (BCT) at different moisture levels. The result showed that it was possibleto accurately predict the load-compression curve of a BCT when moisture was accountedfor.
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| 3. |
- Eriksson, Daniel, 1987-
(författare)
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Getting to grips with cartons : Interactions of carbonboard packages with an artificial finger
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Packaging is an important part of most products in our modern world. It produces waste, but it also enables products to reach consumers safely and efficiently. Hence, the proper design of packaging is becoming increasingly important. Historically, cartonboard packages were designed for box compression strength. While this remains important, there are other types of loads that are important to consider. One such type of load arises from manual handling. As packages as moved and used, consumers need to exert forces on the package. These forces deform and can damage the package.Understanding these interactions can be challenging. By developing a method for quantifying the deformation due to manual handling, it becomes possible to measure and compare a redesigned package with the original to see if the performance has changed. This can aid packaging designers, but it can also be used for product control. The converting process is complex and deviations from specification can be introduced at many points along the production process.In this work, a method for quantifying interactions similar to those in manual handling is presented and evaluated. The method is then applied to study the effect of position and material properties on the mechanics of the interaction. The method is shown to have low variability and be robust to modifications in packaging and experimental design. It was seen that increasing the size of packages from 82 mm to 98 mm corresponded to decreasing the grammage by 10-20%. The method also showed the stiffening effect of corners and flaps, suggesting that the strategic placement of these design elements could help maintain the desired mechanical properties of the package at the point of interaction, provided the most likely point can be predicted.
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