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For the qualification of leather, you need a human! Is that really the case? (#295)
1 expert systemtechnik gmbh, R&D, Bielefeld, North Rhine-Westphalia, Germany
Leather is characterized by a variety of colour, textures and surfaces. However, this diversity is also a problem if one wants to maintain a constant quality considering the uniqueness of the material and the flaws.
The qualification of these flaws is carried out by people who recognize and classify defects based on defined parameters. However, this human factor is known to have a natural performance and capability limit.
The variety of colour, texture and surface represents a huge challenge for an automatism, even using the well-known digital image processing algorithms and other kinds of systems. To many different textures, surfaces and colours make it too complex to perfectly identify the different types of flaws in this natural material.
After years of development work and research, we have created the scan expert automatic+, a system that can detect flaws independently of colour, texture and surface. During our development we have evolved algorithms that can detect all kinds of flaws on the leather. This result is evaluated using state-of-the-art technologies such as artificial intelligence and machine learning. The expert system makes it possible to implement individual and special customer requirements for qualification quickly and flexibly. The system can also be used for leather crust and wet blue.
Do you really need a human being to qualify leather? It won’t take long that machines will take over.
It is possible to qualify leather with less human interaction.
It won’t take long until machines will make the process of the qualification fully automatically.
Keywords: qualification, flaws, algorithms, artificial intelligence, machine learning
Automation in a tannery. TanWare® – discontinuous steps, continuous data. (#267)
1 INCOTEC GMBH, Bielefeld, Germany
TanWare® AUTOMATION and MEASURING systems have been successfully used around the world for 3 decades.
TanWare® AUTOMATION covers automation of all wet processes with sophisticated recipe driven drum controls and systems for water and chemical supply and other auxiliary systems.
TanWare® MEASURING provides automatic in-line measurement of area, thickness as well as classification, sorting, continuous marking, selection, automatic stacking, quality reporting and photo documentation.
INCOTEC is ready to develop the TanWare® i4 for merging and analyzing all these information. The whole data from the tannery is collected centrally in real time. This includes measured data from hides and machines as well as chemicals, water and energy consumption. It is possible to control the machine utilization and settings of not only TanWare® systems, but also other machines as well as manual workspaces.
Already in 1994 INCOTEC had installed a system (called MachineWare) in one of the biggest tanneries in Germany. Every machine and also manual workplaces had its networked terminal, to register the people working and jobs running through, counting hides, measuring various attributes of hides. All terminals were connected to a central middleware server, utilizing a database. Besides the normal handling, various evaluations of the data were created. The system was fully integrated with a tannery specific ERP system with a sophisticated production planning and control. It had a workflow optimization that benefitted greatly from the data collected.
Now in 2019 the TanWare® i4 will evolve to an even more powerful system, bringing industry 4.0 to the tannery.
It enables the full traceability of hides, a perfect preventive maintenance, an automatic production optimization and in addition a paperless production by combining all the modules of digital and non-digital data suppliers.
Keywords: Industry 4.0, Big Data, Automation, Measuring, Workflow
IRIS, in line system for colour quality control (#311)
M. Oomens1, L. de Luca2
1 Im Innovating, Dongen, Netherlands
When expressing the same color, different people refer to different things and describe the exact same color with different words. It is because of this variety of expressions that communicating a particular color is difficult and vague. The difficulty becomes even greater when we get into a production system that has to reproduce colors or producing colored objects. In fact, anyone interested in color problems, be it a dyeing dyer or printer, is aware of the still considerable empiricism that exists when it comes to tackling a color. If we consider the specialization of the tanning chemical dyer, it is enough to remember that a long and tiring training as a sampler is necessary before acquiring sufficient experience to deal with the formulation of dyeing recipes. Moreover, in dyeing processes, the first formulation will rarely be satisfactory and it will still take two or three before reaching tolerance. This is true both in the dyeing processes in the drum and in the pigmentation processes in finishing. Modern science comes to our aid getting in deeper with the analysis of the color and giving a different meaning to the word: the perception in the human eye of an electromagnetic radiation of the visible spectrum. In 1931, the International Commission on Illumination (CIE) developed the xyY colorimetric system that represents colors according to their chromaticity (x and y axes) and their luminance (Y axis). However, this modality of purely mathematical representation does not take into account the psychological factors of the perception of color by the human eye, from which it results that a chromaticity diagram leaves for example a too wide space for green colors. Therefore, in 1976, the CIE elaborates the L * a * b colorimetric model (also known as CIELab), in which a color is identified by three values: L, the luminance, expressed as a percentage (0 for black and 100 for white); a and b two color ranges ranging from green to red and from blue to yellow with values from -120 to +120. The Lab mode thus covers the entire visible spectrum of the human eye. Starting from this assumption, we can measure the color with the colorimeter or the spectrophotometer. But, while the spectrophotometer is a physical analysis tool which provides the wavelength by spectral analysis, the wavelength of reflection and / or transmittance of the property of objects without interpretation of a human being; the colorimeter is a psychophysical analysis tool that provides measurements that correlate with human eye-brain perception. The colorimeter therefore fits perfectly into the tanning industry's service as its main features include: reading data directly from the leathers, working well with similar color routines and adjusting small color differences in constant conditions and, not least, it has a fundamental function in quality control. IRIS, the system for in line color quality control developed by GER Elettronica, in addition to the features already highlighted, allows for continuous monitoring of color quality, being mounted directly on the production lines.
Inline process control, colour monitoring
Keywords: Quality Control, Colour of Leather, Colouring Process, Process Control, Colorimeter
Steel meets leather - The influence of cutting parameters in the leather splitting process (#259)
G. E. Hank1
1 Rudolf Alber GmbH & Co. KG, technical sales, Ebersbach, Baden-Württemberg, Germany
This article wants to combine two perspectives: First, Leather production, focused on the splitting process, with its diverse quality requirements and second, the new evolutions in the field of bandknife properties.
In a short introduction the splitting process as such will be described, its different use in several stages and leather types, also in the field of leather conversion (in shoe, leathergoods and automotive parts production). Influencing factors of the possible goals like quality and cost efficiency will be discussed.
In the second part some main requirements and problem fields of leather splitting are analyzed in more detail.
Requirements such as thickness tolerance, tensile strength, flexibility, fibre-free smooth cutting surface. Difficulties in practice like chrome nests, hard water, poor raw material, feeding speed, influence of abrasivity of leather.
In a third part the physics of the cutting process as such will be described. Explanation of basic terms as “cutting ability”, “edge retention”, “pull vs. press cut”. Resulting from this we get important parameters that refer to the bandknife blade: e.g. steel characteristics (hardness, flexibility, grindeability, microstructure at cutting point, geometry of knife bevels, weldability etc.). The possibilities in modern bandknife production will be shown as for example: CNC-sensor-based tolerance measurements, pre-sharpening, surface roughness variations. This is completed with a short view on the other components of the process like splitting machine (points like sharpness measuring), grinding stones (roughness-exactness controversy diagram).
The fourth and last part puts the two perspectives together: Optimized bandknife characteristics for specific leather material. Alternative steel types that due to new properties allow to meet also new requirements.
Georg Hank, Ebersbach, Germany, Rudolf Alber GmbH & Co. KG, 31.1.2019
Optimization of the splitting process
Better understanding of the bandknife properties
Keywords: Bandknife Steel characteristics, Theory of cutting, Splitting according to leather type
The New Cutting Edge – taking the shaving process to the next Level (#310)
P. Küchler1, J. Nijkamp1
1 HEUSCH GmbH & Co. KG, Aachen, Germany
In today’s competitive industry Tanners are pressured to lower their costs, increase the leather yield per hide/skin and improve their environmental responsibility. In order to meet these challenging requirements from leather producers we at HEUSCH step up to the plate and take our current high quality blades to the next level. The next generation of blades will further optimize the shaving process.
Keywords: shaving process, HEUSCH, New Cutting Edge