process chain
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Author(s):  
Johann Gierecker ◽  
Daniel Schoepflin ◽  
Ole Schmedemann ◽  
Thorsten Schüppstuhl

Abstract Machine vision solutions can perform within a wide range of applications and are commonly used to verify the operation of production systems. They offer the potential to automatically record assembly states and derive information, but simultaneously require a high effort of planning, configuration and implementation. This generally leads to an iterative, expert based implementation with long process times and sets major barriers for many companies. Furthermore the implementation is task specific and needs to be repeated with every variation of product, environment or process. Therefore a novel concept of a simulation-based process chain for both—configuration and enablement—of machine vision systems is presented in this paper. It combines related work of sensor planning algorithms with new methods of training data generation and detailed task specific analysis for assembly applications.


Author(s):  
Daniel Gebauer ◽  
Jonas Dirr ◽  
Gunther Reinhart

AbstractThe assembly of cables in industrial production is still a largely manually performed task. Therefore, automatic cable assembly offers much potential in terms of efficiency. The major challenge of automating this task lies in the formlessness of the cables, which entails unknown and inconstant states of the assembly objects. In this paper, a process chain and a concept are presented for the automated cable assembly in an industrial context. The process chain consists of five process steps, which are used to structure existing approaches and system configurations for automated cable assembly from a production technology perspective. The emphasis is on the coverage of the process steps and the system technology. The presented concept represents an approach for robotic cable assembly focusing on the flexibility to process multiple product variants. Basis for the ability to handle a variety of variants is the avoidance of a forced shape on the cables. For this approach, system technology as well as challenges and possible solutions are presented.


Energies ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 205
Author(s):  
Alexandra Plesu Popescu ◽  
Yen Keong Cheah ◽  
Petar Sabev Varbanov ◽  
Jiří Jaromír Klemeš ◽  
Mohammad Reda Kabli ◽  
...  

Circular economy implementations tend to decrease the human pressure on the environment, but not all produce footprint reductions. That observation brings the need for tools for the evaluation of recycling processes. Based on the Exergy Footprint concept, the presented work formulates a procedure for its application to industrial chemical recycling processes. It illustrates its application in the example of cotton waste recycling. This includes the evaluation of the entire process chain of polyethylene synthesis by recycling cotton waste. The chemical recycling stages are identified and used to construct the entire flowsheet that eliminates the cotton waste and its footprints at the expense of additional exergy input. The exergy performance of the process is evaluated. The identified exergy assets and liabilities are 138 MJ/kg ethylene and 153 MJ/kg ethylene, reducing the Exergy Footprint by 75% and the greenhouse gas footprint by 43% compared to the linear pattern of polyethylene production. The exergy requirements for producing raw cotton constitute a large fraction of the liabilities, while the polyethylene degradation provides the main asset in the reduction of the Exergy Footprint.


Molecules ◽  
2021 ◽  
Vol 26 (23) ◽  
pp. 7317
Author(s):  
Fredrik Weiland ◽  
Muhammad Saad Qureshi ◽  
Jonas Wennebro ◽  
Christian Lindfors ◽  
Taina Ohra-aho ◽  
...  

Petrochemical products could be produced from circular feedstock, such as waste plastics. Most plants that utilize syngas in their production are today equipped with entrained flow gasifiers, as this type of gasifier generates the highest syngas quality. However, feeding of circular feedstocks to an entrained flow gasifier can be problematic. Therefore, in this work, a two-step process was studied, in which polypropylene was pre-treated by pyrolysis to produce a liquid intermediate that was easily fed to the gasifier. The products from both pyrolysis and gasification were thoroughly characterized. Moreover, the product yields from the individual steps, as well as from the entire process chain, are reported. It was estimated that the yields of CO and H2 from the two-step process were at least 0.95 and 0.06 kg per kg of polypropylene, respectively, assuming that the pyrolysis liquid and wax can be combined as feedstock to an entrained flow gasifier. On an energy basis, the energy content of CO and H2 in the produced syngas corresponded to approximately 40% of the energy content of the polypropylene raw material. This is, however, expected to be significantly improved on a larger scale where losses are proportionally smaller.


Micromachines ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1456
Author(s):  
Andreas Rohrmoser ◽  
Martin Kraus ◽  
Marion Merklein

Compared to alternative production methods, cold forming offers technological, economic and ecological potential for the mass production of microgears. Within the current boundaries of the technology, the cold forming of modules m < 0.2 mm is not possible due to size effects, high tool stresses and handling problems. The investigations of this contribution present a novel process chain for the multi-step forming of microgears with a module of m = 0.1 mm. For this purpose, a numerical model of the first two steps of the process chain is set up and confirmed based on experimental forming tests. The results have proven the feasibility of the process chain by a complete forming of the gear teeth.


Materials ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 6822
Author(s):  
Xuefei Wei ◽  
Alexander Krämer ◽  
Gerhard Hirt ◽  
Anett Stöcker ◽  
Rudolf Kawalla ◽  
...  

The magnetic properties of non-oriented electrical steel, widely used in electric machines, are closely related to the grain size and texture of the material. How to control the evolution of grain size and texture through processing in order to improve the magnetic properties is the research focus of this article. Therefore, the complete process chain of a non-oriented electrical steel with 3.2 wt.-% Si was studied with regard to hot rolling, cold rolling, and final annealing on laboratory scale. Through a comprehensive analysis of the process chain, the influence of important process parameters on the grain size and texture evolution as well as the magnetic properties was determined. It was found that furnace cooling after the last hot rolling pass led to a fully recrystallized grain structure with the favorable ND-rotated-cube component, and a large portion of this component was retained in the thin strip after cold rolling, resulting in a texture with a low γ-fiber and a high ND-cube component after final annealing at moderate to high temperatures. These promising results on a laboratory scale can be regarded as an effective way to control the processing on an industrial scale, to finally tailor the magnetic properties of non-oriented electrical steel according to their final application.


2021 ◽  
Vol 1 ◽  
pp. 23-24
Author(s):  
Chang Li ◽  
Siavash Kazemi ◽  
Sascha Gentes

Abstract. Nowadays, concrete decontamination is done by, e.g., grinding, milling, etc., always combined with labor resources. In order to relieve employees from the monotonous and physically stressful decontamination work, a novel milling system for automated surface decontamination has been developed and assembled. The current work presents this new concept for a milling tool that could automatically position itself to the wall surface and subsequently remove surface contamination. A process chain (Fig. 1) defined in the German Federal Ministry of Education and Research (BMBF)-funded project ROBDEKON was introduced first. The chain consists of a total of five steps for a compact process, from environmental exploration to the transportation of waste. This automated decontamination is the third step in the process chain for decontamination of building structures in nuclear facilities. The structure (Fig. 2) of the milling system and the function of each component are then explained in detail. With the assembled sensors, such as a laser distance sensor, a force sensor etc., the various physical quantities can be measured in real time, thus enabling automation of the milling process during decontamination.


2021 ◽  
pp. 261-268
Author(s):  
Nicola Viktoria Ganter ◽  
Stefan Plappert ◽  
Paul Christoph Gembarski ◽  
Roland Lachmayer

2021 ◽  
Vol 426 ◽  
pp. 127761
Author(s):  
Lewin Rathmann ◽  
Lucas-Hermann Beste ◽  
Tim Radel
Keyword(s):  

Author(s):  
Tejas Mankeekar ◽  
Dirk Bähre ◽  
Dan Durneata ◽  
Thomas Hall ◽  
Rainer Lilischkis ◽  
...  

AbstractA new, scalable process chain for the fabrication of curved micro-structured metallic tools is developed and evaluated. Arrays of arrows, circles, semicircles and rings with final lateral dimensions of 124 to 819 µm are realised on the tools and successfully transmitted in one process step to stainless steel workpieces with a functional area of 6.5 cm2 using pulsed electrochemical machining. Photolithography-etching or micromilling are applied as initial micro-structuring processes, resulting in micro-structured master forms. These forms are copied into reusable silicon forms. This is followed by epoxy casting and electroforming to obtain the final tools. The tools are made of Nickel and have a diameter of 34 mm. Whilst micromilling, photolithography, silicon casting, epoxy casting and electroforming copy the structures very precisely, the wet etching process induces a widening of the dimensions due to the isotropic character of the process. The advantage of the process chain is the reusability of the master as well as of the silicone forms, which can be copied very precisely and easily with scalable processes to get precision tools with relatively large micro-structured areas. The reusability of the forms makes the fabrication of micro-structured tools relatively cost-efficient. The use of photolithography as the initial structuring process enables the generation of arbitrary, user-defined geometries for the micro-structures on the tool surface. The process chain described has the potential to fabricate lateral structure sizes on tools down to one micrometre.


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