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1

Modernisation of the workplace as a result of the outbreak of the pandemic

Kania A., Polok-Rubiniec M., Włodarczyk-Fligier A.

Journal of Achievements in Materials and Manufacturing Engineering

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2023

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Vol. 118, nr 2

69--77

EN

Purpose of this paper is to propose modernisation activities, including the improvement of machines and devices that will increase work safety during the epidemic state for the workplace of an injection moulding machine operator in a selected manufacturing company. Design/methodology/approach In the work brief analyses of a production line and a workplace of an injection moulding machine operator were carried out. Then the threats that occur at the analysed workplace were identified. The risk assessment was done using three methods: matrix according to the PN-N-18002:2011 standard, Risk Score and PHA. Findings The results of the occupational risk assessment obtained by the three assessment methods were similar and gave similar results. The greatest and unacceptable risk has occurred for the threat of SARS-CoV-2 virus infection. Therefore, the following modernisation solutions were proposed: the introduction of mandatory epidemiological questionnaires, online training for company employees, the use of a three-axis robot, replacement of traditional disinfection dispensers with automatic ones. Practical implications The results of re-assessing the occupational risk after introducing the proposed improvements showed that the occupational risk was significantly reduced – mainly to the low or very low levels. Originality/value The proposed modernisation solutions at the workplace of an injection moulding machine operator can be used for each workplace and each epidemiological state.

2

Investigation of Multi-Cold Rolling Passes on Mechanical Characteristics and Surface Quality of AlCuV Alloy

Shaban Nabeel Abu, Al-Qawabah Safwan, Alkhaldi Hashem S.

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 5

68--76

EN

In this study, the effect of rolling angle orientation namely; 0, 45, and 90 degrees, and three rolling passes on the mechanical behavior of Al-Cu after vanadium addition were investigated. Al-4%Cu and Al-4%Cu-0.1%V sheets were produced and rolled from 4 mm to 3 mm followed by 3 to 2 mm, and finally from 2 mm to 1.3 mm. After each pass, the tensile test was performed in three directions from which the maximum tensile force, deformation energy, microhardness, and average surface roughness (Ra) were determined. A pronounce finding is that the addition of both additions of 0.1% vanadium to Al-4%Cu alloy and multi-rolling passes resulted in reducing the deformation energy by 85.4, and the maximum tensile forces reduced by 56.6%, this resulted in reduction of production cost of AlCuV alloys, furthermore, it resulted in reducing the anisotropy of AlCuV alloy. Additionally, the average microhardness was enhanced for Al-Cu and AlCuV alloy, whereas the Ra was in maximum enhanced for AlCuV alloy of about 64.9%.

3

Assessment of classification with variable air flow for inertial classifier in dry grinding circuit with electromagnetic mill using partition curves

Wolosiewicz-Glab M., Ogonowski S., Foszcz D., Gawenda T.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 2

440--447

EN

In classification one of the methods used to evaluate the effectiveness of classifier’s work is to create the partition curve, which determines the size of the classified particles and characterizes the accuracy of the process. The article presents the results of experiments showing the efficiency of classification in the inertial classifier, designed specifically for the electromagnetic mill. The paper presents the results of tests in order to determine the possibility of controlling the classification by changing the transport air stream flow. In order to verify and assess the classifier work, a series of experiments with different opening level of additional air damper was performed. The results allow thorough assessment of the effectiveness and efficiency of the device and facilitate the optimization of the grinding process by establishing an appropriate control algorithm as well as the air flow in classifier.

4

Strategy for the selection of the best phase transformation model for simulation of metals processing

Rauch Ł., Bzowski K., Perzyński K., Madej Ł., Milenin A., Pietrzyk M.

Computer Methods in Materials Science

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2016

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Vol. 16, No. 4

224--237

EN

Connection of the finite element program with phase transformation models is often needed when prediction of distribution of phase composition in the product is of interest. Depending on the type of the phase transformation model this connection may involve long computing times. Moreover, when the optimization task has to be formulated and solved, the computing costs may radically increase. It is particularly troublesome when the objective function is composed of advanced microstructural parameters or product properties, evaluation of which requires an application of multiscale modelling techniques. In the present paper the possibilities of decreasing of the computing costs for optimization of metals processing were explored. Several case studies, which require connection of the FE code with phase transformation models, were analysed and computing times were compared. Efficiency of modelling depending on the complexity of the macro scale FE mesh was evaluated.

PL

Połączenie programu z metody elementów skończonych (MES) z modelem przemian fazowych jest niezbędne, kiedy potrzebna jest informacja o rozkładzie składu fazowego w wyrobie gotowym. W zależności od rodzaju modelu przemian fazowych takie połączenie może pociągać za sobą bardzo długie czasy obliczeń. Ponadto, kiedy dodatkowo musi zostać sformułowane i rozwiązane zadanie optymalizacyjne, koszty obliczeń mogą jeszcze radykalnie wzrosnąć. Jest to szczególnie kłopotliwe, kiedy funkcja celu zawiera zaawansowane parametry mikrostruktury lub własności wyrobu, których obliczenie wymaga zastosowania modelowania wieloskalowego. W niniejszej pracy analizowano możliwości skrócenia czasów obliczeń związanych z optymalizacją procesów przetwórstwa metali. Porównano czasy obliczeń dla symulacji różnych procesów, w których potrzebne jest połączenie MES z modelami przemian fazowych. Oceniono efektywność modelowania w zależności od złożoności siatki MES w skali makro.

5

Non-isothermal hydromagnetic convection in a porous medium with heat sink: hypergeometric function solutions

Beg O. A., Takhar H. S., Beg T. A., Singh A. K.

International Journal of Applied Mechanics and Engineering

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2007

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Vol. 12, no 2

337-351

EN

The present paper deals with the free convection laminar boundary layer flow and heat transfer of an incompressible, electrically conducting, viscous fluid through a porous medium caused by stretching a porous wall in the presence of a heat source and under the influence of uniform magnetic field. Exact solutions of the basic equations of momentu m and energy ar e obtained after reducing them i n to non-linear ordinary differential equations and using confluent hypergeometric functions. The variations in the velocity field and temperature distribution with the Prandtl number (Pr), hydromagnetic parameter (M), permeability param eter (K), suction parameter (N), wall temperature parameler (S), and the heat sink parameter (Q) are obtained and depicted graphically. The skin-friction at the wall is also derived, and the numerical values for various physical parameters are also tabulaled. Magnetic field (M) is seen to reduce both longitudinal and translational velocities and also lower temperalures, aiding in controlling momentum and heat transfer during materiaIs processing. Suction (N) posivitely influences the transverse velocity but depresses the longitudinal velocity magnitudes as we II as decreasing tempcratures. Suction therefore also assists in controlling heat transfer in Ihe boundary layer. Increasing permeability parameter (K) depresses the longitudinal velocity but elevates transverse velocities and increases the skin friction at the wall. Both rising temperature (non-isothermal wall) parameter (S) and heat sink parameter (Q) decrease temperature values. The model finds applications in nucIear engineering control systems and MHD energy systems.

6

Badania wydajności objętościowej w procesie drążenia laserowego aluminium

Zimny J., Fiszer T.

Zeszyty Naukowe Politechniki Częstochowskiej. Budownictwo

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2002

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Z. 9 (154)

139-155