In-line Production Research Articles

Ensuring the reliability of automated pulse electric spark control of pipe coatings in in-line production

The issues of ensuring the reliability of automated electric spark testing of the continuity of dielectric coatings on metal pipes with diameters up to 1.5 meters in the context of in-line manufacturing are addressed. A simulation of the “high-voltage pulse source – electrode – dielectric coating – metal substrate” system has been conducted. Experimental studies have been conducted to evaluate the load capacity and voltage stability of the Corona 2.2 holiday detector using an improved generator at high capacitive loads.

Processing and characterisation of hot rolling pressed PVDF films with enhanced field-induced polarisation

Poly (vinylidene fluoride) (PVDF) based polymers are good candidates for high-power energy storage in dielectric capacitors. So far, most studies reporting PVDF with high energy density are based on solution casting, a method ill-suited for large-scale production. In this work, we develop PVDF films with high crystallinity (47%) and ultrahigh β-phase (∼97%) using Hot Rolling Press (HRP). During HRP, the crystallinity, fraction of β-phase, internal stress, and the piezoelectric coefficient d33 increased with rolling temperature. The anisotropic stress imposed by two rollers led to a highly preferred orientation of the HRP film along the rolling direction. Notably, the HRP film exhibits an enhanced field-induced polarisation Pin-max value (0.16 C m−2) compared to conventional PVDF films (0.10 C m−2), with an energy density of 32.6 J cm−3 at 871 kV mm-1. The good low field dielectric (εr ∼19 @ 1 kHz) and piezoelectric (d33 ∼30 pC N-1) properties with high-temperature stability (up to 100 °C), and its suitability for in-line continuous production, make HRP PVDF films promising for low field dielectric and piezoelectric applications.

Evaluation of thermal damaged die steel through magnetic emission technique

This paper describes the potential of magnetic hysteresis loop (HL) technique to monitor the thermally damaged regions of hardened AISI H13 die steel. To overcomes this thermal damage issue, minimum quantity lubrication grinding with bio-lubricants like castor oil, biodegradable oil, and Al2O3 nanofluid was adopted. HL parameters i.e., average permeability and coercivity linearly correlated with average grain size, microhardness, and full width at half maximum (FWHM) and its correlational coefficient of ∼0.8959, ∼0.9661, ∼0.9278, ∼0.9652, ∼0.9485, and ∼0.9870, respectively. The alteration in the steepness of the HL envelope well agrees with the dominant role of microhardness and FWHM. It is concluded that an inspection of ground die steel during in-line production, HL should be calibrated concerning surface properties.

YOLOv5 based object detection in reel package X-ray images of semiconductor component

The industrial manufacturing landscape is currently shifting toward the incorporation of technologies based on artificial intelligence (AI). This transition includes an evolution toward smart factory infrastructure, with a specific focus on AI-driven strategies in production and quality control. Specifically, AI-empowered computer vision has emerged as a potent tool that offers a departure from extant rule-based systems and provides enhanced operational efficiency at manufacturing sites. As the manufacturing sector embraces this new paradigm, the impetus to integrate AI-integrated manufacturing is evident. Within this framework, one salient application is AI deep learning–facilitated small-object detection, which is poised to have extensive implications for diverse industrial applications. This study describes an optimized iteration of the YOLOv5 model, which is known for its efficacious single-stage object-detection abilities underpinned by PyTorch. Our proposed “improved model” incorporates an additional layer to the model's canonical three-layer architecture, augmenting accuracy and computational expediency. Empirical evaluations using semiconductor X-ray imagery reveal the model's superior performance metrics. Given the intricate specifications of surface-mount technologies, which are characterized by a plethora of micro-scale components, our model makes a seminal contribution to real-time, in-line production assessments. Quantitative analyses show that our improved model attained a mean average precision of 0.622, surpassing YOLOv5's 0.349, and a marked accuracy enhancement of 0.865, which is a significant improvement on YOLOv5's 0.552. These findings bolster the model's robustness and potential applicability, particularly in discerning objects at reel granularities during real-time inferencing.

Thermomechanical Analysis of Thermoplastic Mono-Material Sandwich Structures with Honeycomb Core

The application of fiber-reinforced thermoplastic mono-material sandwich panels has many advantages, such as recyclability, reduction in processing cycle times, integration of additional elements by means of welding, and a great potential for in-line production. The most efficient way to produce a curved thermoplastic sandwich panel is thermoforming, which has several challenges. One of them is to achieve a higher thermal gradient in the panel. On the one hand, the temperature at the skin–core interface must exceed the softening point of the polymer to reach a sufficient bonding degree. On the other hand, the core should not be overheated and overloaded to avoid its collapse. Furthermore, several fiber distortions, such as wrinkles or buckles, can be developed during thermoforming. All these flaws have a negative impact on the mechanical performance of the sandwich structure. The objective of this study is the development of a simulation tool for the thermoforming process, which can replace the time-consuming trial-and-error-based method. Therefore, a coupled thermomechanical model was developed for a novel thermoplastic sandwich structure, which is able to predict the temperature distribution and its influence on the mechanical properties of the panel. Experimental trials were conducted to validate the thermomechanical forming model, which demonstrated a good agreement with numerical results.

Research into the assembly production cycle and ways reduce it

The structure of the production cycle, the forms of its temporal and spatial configuration are conside red for the purpose of quantitative and qualitative analysis of the production cycle and the further development of me thods for assessing the efficiency of production organization. The assembly process, principles and methods of its organization are studied, production planning systems are briefly described, and ways to shorten the cycle are researched. Keywords production cycle, lean manufacturing, efficiency of production organization, assembly process, in-line production, cycle reduction

Experimental Validation of a Micro-Extrusion Set-Up with In-Line Rheometry for the Production and Monitoring of Filaments for 3D-Printing.

The main objective of this work is to validate an in-line micro-slit rheometer and a micro-extrusion line, both designed for the in-line monitoring and production of filaments for 3D printing using small amounts of material. The micro-filament extrusion line is first presented and its operational window is assessed. The throughputs ranged between 0.045 kg/h and 0.15 kg/h with a maximum 3% error and with a melt temperature control within 1 °C under the processing conditions tested for an average residence time of about 3 min. The rheological micro slit is then presented and assessed using low-density polyethylene (LDPE) and cyclic olefin copolymer (COC). The excellent matching between the in-line micro-rheological data and the data measured with off-line rotational and capillary rheometers validate the in-line micro-slit rheometer. However, it is shown that the COC does not follow the Cox-Merz rule. The COC filaments produced with the micro-extrusion line were successfully used in the 3D printing of specimens for tensile testing. The quality of both filaments (less than 6% variation in diameter along the filament's length) and printed specimens validated the whole micro-set-up, which was eventually used to deliver a rheological mapping of COC printability.

High-quality electrostatic recycling of waste carbon fiber via spark-driven shock waves and Joule heating

The recycling of waste carbon fibers (CF) has emerged as a crucial research area for both environmental protection and economic sustainability. To sufficiently exert the potential and extend the application life cycle of CFs, here we propose an eco-friendly and efficient electrostatic method for rapid recycling of tightly entangled reclaimed carbon fibers (rCFs) by spark-driven disentanglement and depolymerization. Our research indicates that the spark discharge generated by fiber induction under low-voltage conditions can excite the shock waves and Joule heating effects, resulting in the separation of individual rCFs and the removal of surface organic matrix. Furthermore, the constructed electric field can synchronously and continuously orient the dispersed rCFs to form a vertical alignment in a short time with good maneuverability and directionality for reutilization. The results demonstrate that this one-step disentanglement, depolymerization, and alignment method achieves a high-quality recycling process with 100% dispersion efficiency, minimal damage, cost-effectiveness, uniform distribution, upright orientation, and high-speed embedding performance. Our findings reveal the potential of the electrostatic strategy for the high-quality recycling of rCFs, in line with the principles of the circular economy. The proposed method offers broad prospects for application in continuous in-line production and material manufacturing, and is a step towards sustainable and cost-effective CF recycling.

Industrial Graphene Coating of Low-Voltage Copper Wires for Power Distribution.

Copper (Cu) is the electrical conductor of choice in many categories of electrical wiring, with household and building installation being the major market of this metal. This work demonstrates the coating of Cu wires-with diameters relevant for low-voltage (LV) applications-with graphene. The chemical vapor deposition (CVD) coating process is rapid, safe, scalable, and industrially compatible. Graphene-coated Cu wires display good oxidation resistance and increased electrical conductivity (up to 1% immediately after coating and up to 3% after 24 months), allowing for wire diameter reduction and thus significant savings in wire production costs. Combined spectroscopic and diffraction analysis indicates that the conductivity increase is due to a change in Cu crystallinity induced by the coating process conditions, while electrical testing of aged wires shows that graphene plays a major role in maintaining improved electrical performances over long periods of time. Finally, graphene coating of Cu wires using an ambient-pressure roll-to-roll (R2R) CVD reactor is demonstrated. This enables the in-line production of graphene-coated metallic wires as required for industrial scale-up.

PETRI NET MODELING OF A PRODUCTION SYSTEM WITH PARALLEL MANUFACTURING PROCESSES

This paper presents the modelling and control of a flexible manufacturing system with integrated Industry 4.0 concepts using Petri nets. The flexible manufacturing system is composed of 7 workstations that ensure the assembly and disassembly of two types of products on two parallel production processes. The two parallel processes, in-line and in-cell production processes, ensure the assembly of the products and disassembly of the defects with a minimal number of stations. wo types of controls, local and centralized, are implemented in the control of production processes. The local control, based on the PLCs of each station, ensures the control of the assembly process at the workstation level. The centralized control ensures the obtaining of desired results at the level of interaction between the stations and also the implementation of the optimization algorithm results. To better understand and develop the control of the system a Petri net model was developed. Based on the properties of the Petri nets was possible to simulate and verify the assembly process and data flow inside the flexible manufacturing system. The developed model also ensures no bottlenecks at the data transmission and processing of the production information from the client to the production hardware.

A self-consistent hybrid model connects empirical and optical models for fast, non-destructive inline characterization of thin, porous silicon layers

Epitaxially-grown wafers on top of sintered porous silicon are a material-efficient wafer production process, that is now being launched into mass production. This production process makes the material-expensive sawing procedure obsolete since the wafer can be easily detached from its seed substrate. With high-throughput inline production processes, fast and reliable evaluation processes are crucial. The quality of the porous layers plays an important role regarding a successful detachment. Therefore, we present a fast and non-destructive investigation algorithm of thin, porous silicon layers. We predict the layer parameters directly from inline reflectance data by using a convolutional neural network (CNN), which is inspired by a comprehensive optical modelling approach from literature. There, a numerical fitting approach on reflection curves calculated with a physical model is performed. By adding the physical model to the CNN, we create a hybrid model, that not only predicts layer parameters, but also recalculates reflection curves. This allows a consistency check for a self-supervised network optimization. Evaluation on experimental data shows a high similarity with Scanning Electron Microscopy (SEM) measurements. Since parallel computation is possible with the CNN, 30.000 samples can be evaluated in roughly 100 ms.

Intelligent data analysis in an automated system of input control of raw materials on a continuous process line for the production of meat products

The article considers conditions for partial grinding of a frozen meat block in case of detection of extraneous inclusion in it by the raw material input control system. The processing of raw materials occurs on an automated in-line production line for meat products using a single-stage chopping process. The authors stipulate a continuous inspection of all meat blocks with full automation of control operations. Localization of the layer of meat containing inclusion solves the trajectory problem of moving the block of raw materials in the guiding planes of the single-stage chopper with the establishment of a mandatory safe chopping zone. The analysis helps to determine the boundaries of the safety zone. When solving the trajectory problem, the authors accept the assumption of a rectilinear trajectory of movement of a block of meat during its single-stage chopping. The foundation of this presumption stems from a research study of the energy usage of the drive of the raw material cutting mechanism in the working mode. The calculation of estimates of numerical characteristics of the experimental distribution of power consumption of the electric motor drive of the cutting mechanism allows to judge about the reduction of dynamic loads in the technological system “shredder - meat block” causing deviations from the plane-parallel motion of the meat block, because of rigid fixation of the block in the cutting zone. Using the control system reduces the risks of using substandard raw materials within its competence while maintaining the productivity of the technological line.

Applicability of ultrasonic welding to Ag-stabilized REBCO CC joints and evaluation of their electromechanical properties

Manufacturing a single long-length rare-earth barium copper oxide (REBCO) coated conductor (CC) tape with uniform critical current (I c) is still a challenge; therefore, joining between multiple-length CC tapes is needed in the production of longer CC tapes for superconducting cables, coils, and magnets. Various joining techniques have been developed to achieve acceptably low joint resistance (R j) with no I c degradation and good electromechanical properties. The authors established ultrasonic welding (UW) and hybrid welding (HW) methods for joining Cu-stabilized CC tapes with different configurations. However, these methods have yet to be applied to Ag-stabilized CC tapes to produce compact joints and longer tapes during in-line production. This study used the UW and HW methods to fabricate Ag-stabilized CC joints to have low R j without I c degradation through a direct connection at the overlapped Ag layers between both CC tapes. Two CC tape samples with different thicknesses of ∼2 µm and ∼6 µm Ag stabilizers were supplied to produce UW and HW Ag-stabilized CC joints. These were compared with soldered CC joints fabricated by a mechanically controlled soldering method. In the case of UW, the design of experiment using the Taguchi method was used to systematically determine the optimized weld parameter combination that yields a lower R j without any I c degradation. This study is a systematic attempt to evaluate the applicability of UW for solid-state joining between thin Ag layers, unlike the conventional joining of thick Cu stabilizers. Moreover, the electromechanical properties of differently processed Ag-stabilized REBCO CC joints were evaluated using both lap-shear and double-bending tests. As a result, the optimum UW parameter combinations were obtained to achieve Ag-stabilized CC joints. However, some variations were probably due to the differences in the production batch and thickness of the Ag layers. The UW Ag-stabilized CC joints showed superior joint characteristics and electromechanical properties compared to soldered CC joints. Good solid-state bonding of the Ag layers was observed through microscopic observation of the cross-section at the joint region of the UW CC joint. The joint characteristics and electromechanical properties of the UW Ag-stabilized CC joints can be further improved using the HW method.

Highly Efficient 2D Materials Engineered Perovskite/Si Tandem Bifacial Cells Beyond 29%

Perovskite/Silicon tandem technology represents a promising route to achieve 30% power conversion efficiency (PCE), by ensuring low levelized costs energy. In this article, we develop a mechanically stacked 2T perovskite/silicon tandem solar cell, with subcells independently fabricated, optimized, and subsequently coupled by contacting the back electrode of the mesoscopic perovskite top cell with the texturized and metalized front contact of the silicon bottom cell. The possibility to separately optimize the two sub-cells allows to carefully choose the most promising device structure for both top and bottom cells. Indeed, semitransparent perovskite top cell performance is boosted through the use of selected two-dimensional materials to tune the device interfaces. In addition, a protective buffer layer is used to prevent damages induced by the transparent electrode sputtering deposition over the hole transporting layer. A textured amorphous/crystalline silicon heterojunction cell fabricated with a fully industrial in-line production process is here used as state of art bottom cell. The perovskite/c-Si tandem device demonstrates remarkable PCE of 28.7%. Moreover, we demonstrate the use of a bifacial silicon bottom cell, as a viable way for overcoming the current matching constrain imposed by the 2T configuration. Here, the current generation difference between perovskite and c-Si cells is compensated by exploiting the albedo radiation thanks to the bifaciality of the commercial c-Si cell used in this article. Considering standard rear irradiation, final power generation density above 32 mW/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> can be achieved, paving the way for a tandem technology customable according to the final installation site.

A Real-Time Automated Defect Classification System Based on Two-Step Convolutional Neural Network

The increasing amount of defect images in semiconductor manufacturing process imposes the demand of classifying these images in real-time. In this paper we adopt a two-step deep learning based Convolutional Neural Network (CNN) to detect and classify the defect images from clean ones. The proposed method integrates the detection and classification process into one forward step, which takes image-level feature as well as empirical defect classification rules into account. In practice, the Real-Time Automated Defect Classification (RT-ADC) system was deployed in inline production process, which brings high efficiency; better wafer analysis and root cause determination for yield enhancement.

Development of Liquid Crystal Layer Thickness and Refractive Index Measurement Methods for Scattering Type Liquid Crystal Displays

Abstract We report the measuring method of scattering type display liquid crystal layer thickness based on capacitance values suitable for inline production process control. The method is selected for its effectiveness and simplicity over spectroscopic methods as conventional methods for scattering type displays are not applicable. During the method approbation process, a novel diffuser liquid crystal mixture refractive index was determined based on liquid crystal layer thickness measurement data.

Development and justification of the thermal parameters of a mechanized rotary blancher

The design of a continuous rotary blancher for moisture-thermal processing of grapes and fruits before laying them for drying has been developed. Taking into account the conditions of mechanization of this process, we expressed a working hypothesis about the possibility of creating such means, the action of which will provide a continuous technology for the flow of all operations that make up the heat treatment process. It includes the minimum heat consumption for the process, design and kinematic parameters, which will allow mechanizing technological operations with the specified modes of their operation and preparing the processed product for further drying in the continuous in-line production of raisins. A method for calculating the thermal load of a blancher is given.

Estimation of the FST-Layering Time for Shock Ignition ICF Targets

The challenge in the field of inertial confinement fusion (ICF) research is related to the study of alternative schemes for fuel ignition on laser systems of medium and megajoule scales. At the moment, it is considered promising to use the method of shock ignition of fuel in a pre-compressed cryogenic target using a focused shock wave (shock- or self-ignition (SI) mode). To confirm the applicability of this scheme to ICF, it is necessary to develop technologies for mass-fabrication of the corresponding targets with a spherically symmetric cryogenic layer (hereinafter referred to as SI-targets). These targets have a low initial aspect ratio Acl (Acl = 3 and Acl = 5) because they are expected to be more hydrodynamically stable during implosion. The paper discusses the preparation of SI-targets for laser experiments using the free-standing target (FST) layering method developed at the Lebedev Physical Institute (LPI). It is shown that, based on FST, it is possible to build a prototype layering module for in-line production of free-standing SI-targets, and the layering time, τform, does not exceed 30 s both for deuterium and deuterium-tritium fuel. Very short values of τform make it possible to obtain layers with a stable isotropic fuel structure to meet the requirements of implosion physics.

Lightweight Components Manufactured with In-Production Composite Scraps: Mechanical Properties and Application Perspectives

&lt;div class="section abstract"&gt;&lt;div class="htmlview paragraph"&gt;In the last years, the design in the automotive sector is mainly led by emission reduction and circular economy. To satisfy the first perspective, composites materials are being increasingly used to produce lightweight structural and semi-structural components. However, the automotive mass production arises the problem of the end-of-life disposal of the vehicle and the reduction of the wastes environmental impact. The circular economy of the composite materials has therefore become a challenge of primary importance for car manufacturers and tier 1 suppliers. It is necessary to pursue a different economic model, combining traditional raw materials with the intensive use of materials from recycling processes. New technologies are being studied and developed concerning the reuse of in-line production scraps with out-of-autoclave process that makes them desirable for high production rate applications.&lt;/div&gt;&lt;div class="htmlview paragraph"&gt;In this frame, a methodology for the reuse of prepreg cutouts coming from in-line ply cutting process is proposed. Production cutouts (scraps, or chops) are used as a charge to manufacture components through the compression molding process. The structure of the final part keeps in meso-scale the same orthotropic orientation of the chops, although it is quasi-isotropic from a macroscopic point of view. Accordingly, standard three-point bending, and tensile mechanical tests were performed to characterize the mechanical behavior of the material.&lt;/div&gt;&lt;div class="htmlview paragraph"&gt;Failure modes and fracture propagation were analyzed too. The chop interface resulted to affect the mechanical performance. Before material failure, multiple damage precursor sites nucleated, generally in correspondence of the chop interfaces. Delamination, brittle fracture of the matrix and debonding between the chops were the main failure modes. The results of the standard coupon tests evidenced good performance of the material in terms of strength and stiffness, despite lower than standard 2x2 twill structure, making the studied material suitable for semi-structural purposes. Accordingly, a prototype of an accelerator pedal frame was produced, in order to evaluate the feasibility, the potential limitations and the aspects to be optimized for the manufacturing of a more complex component.&lt;/div&gt;&lt;/div&gt;

Spectroscopic Approach for the On-Line Monitoring of Welding of Tanker Trucks

The appearance of defects during the manufacture of tanker trucks via arc-welding is a significant problem in the industry. A reliable low-cost and non-destructive on-line method could aid the discovery of solutions to overcome productivity problems. Plasma optical spectroscopy was employed in this study to correlate the presence of several elemental emission lines with certain quality-related events, such as the appearance of porosities. Results obtained through field trials and also during in-line production show that the convenient processing of acquired process signals facilitates not only the detection of defects, but also the identification of their causes. Output monitoring signals have been compared with X-ray inspections of the seam welds performed. It has been demonstrated that the spectroscopic monitoring variables obtained are good indicators for evaluating contamination in the process and therefore the occurrence of welding defects.