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A method is outlined that can be adopted for measuring the power demand by moulding sand mixers using a dedicated computer system enabling the monitoring and recording of instantaneous voltage and current levels of power taken up by foundry machines and installations. This system allows the operational parameters of electric-powered devices to be effectively monitored. Of particular importance is the energy efficiency level. Monitoring of the machine operation is also required for evaluation of the sand preparation processes. The methodology of measurements and processing of measurement data is explained using the example of a state-of-the-art rotary mixer for laboratory applications. Tests have confirmed the adequacy and good performance of the microprocessor system used in measurements, allowing the energy efficiency parameters of the mixer drive to be determined. The fundamental aspects involved in power demand monitoring include: optimisation and control of the mixing process, taking into account the sand quality and mixer performance. It has to be emphasised that the measurement results can be also utilised in optimisation of the machine's constructional and operational features. Tests confirm that variations of moisture content in sand can impact on selected power energy parameters.Keywords: foundry engineering, foundry machines, moulding sand mixers W artykule przedstawiono metodykę pomiarów poboru mocy przez mieszarki masy formierskiej, z zastosowaniem oryginalnego komputerowego systemu przeznaczonego do monitorowania i rejestracji chwilowych wartości napięć, prądów i mocy pobieranej przez odlewnicze maszyny i urządzenia. System ten umożliwia kontrolę eksploatacyjnych parametrów urządzeń o napędzie elektrycznym. Istotnym parametrem jest energochłonność. Poprzez monitorowanie pracy urządzeń, możliwa jest również ocena procesu technologicznego sporządzania masy formierskiej. Metodykę pomiarów oraz sposób analizy wybranych wyników omówiono na przykładzie badań nowoczesnej, wirnikowej mieszarki laboratoryjnej. Przeprowadzone badania potwierdziły funkcjonalność i przydatność zastosowanego w pomiarach mikroprocesorowego systemu. Umożliwia on określenie szeregu istotnych parametrów z punktu widzenia energochłonności pracy napędów mieszarki. Podstawowe, istotne aspekty monitoringu poboru mocy to: optymalizacja i kontrola procesu mieszania, uwzględniająca jakość sporządzanej masy formierskiej oraz ocenę poprawności pracy mieszarki. Podkreślenia wymaga również możliwość wykorzystania wyników pomiarów w optymalizacji konstrukcji i eksploatacji urządzenia. W badaniach potwierdzono wpływ zmiany wilgotności masy na wybrane parametry energetyczne.

Applications of Monitoring of Electric Power Parameters to Performance Evaluation of a Model Vacuum-Assisted Moulding Installation Vacuum conditions in foundry installations are generated using electric-driven vacuum pumps. The purpose of the experiment is to evaluate the performance of a vacuum-assisted system for compaction of moulding sand basing on registered plots of selected electric power parameters of the power-supplying system of the pumps. Model testing done on an experimental vacuum system installation, power-supplied from a system incorporating the recorders of instantaneous current and voltage values. Following the numerical procedure, the experimental data are analysed to yield mathematical relationships between the variations of the generated vacuum pressure levels and variations of selected electric power parameters. Registered and computed values of selected parameters: instantaneous and RMS voltage and current values, active, reactive and apparent power levels and power coefficient allow for diagnosing the adequacy and reliability of the system operation. According to the authors, the applied monitoring of the power parameters of a vacuum-assisted installation may become an effective and easy practical method of evaluating the performance of such installations, used also in foundry plants.

Systemic approach to design of factories requires that engineering, organisational and economic aspects should be considered concurrently. That prompts the need to develop a solution, based on the state-of-the-art IT technologies, to enable us to solve the problems associated with foundry production planning. The paper outlines a methodology of creating the simulation model of a virtual foundry, as a tool for foundry design. An integrative approach is suggested for development of a complete foundry model, enabling the design of more efficient production systems. The underlying principles of such models are discussed, the basic stages involved in the methodology are outlined and the range of its applicability is defined.Keywords: Virtual foundry, Modeling, SimulationSystemowe podejście do projektowania bądź rekonstrukcji systemów wytwarzania wymaga równoległego rozpatrywania zagadnień technologicznych, technicznych, organizacyjnych i ekonomicznych. Stwarza to potrzebę opracowania rozwiązania, opartego na najnowszych osiągnięciach technologii informatycznych, pozwalającego na kompleksowe rozwiązywanie problemu projektowania systemów produkcji odlewniczej. W pracy przedstawiono metodykę tworzenia (budowy) modelu symulacyjnego tzw. wirtualnej odlewni jako narzędzia projektowania zakładu odlewniczego. Zaproponowano iteracyjne podejście tworzenia kompleksowego modelu odlewni, dające w efekcie możliwość projektowania bardziej wydajnych systemów wytwórczych. Przedstawiono zasady konstrukcji takiego modelu, opisano podstawowe etapy metodyki oraz określono możliwości jej zastosowania.

A foundry plant as a manufacturing system operates in accordance with the methods and principles making up the entire process of casting production, involving the use of machines and installations. One of the factors transforming the foundry plant's static structure into the dynamic -processing structure is the compressed air. Practically each procedure making up the casting manufacturing process involves compressed air. Its sources include compressor machines connected to the receiving tanks, making up the compressed air transport installation. Two major aspects are to be addressed in compressed air management: the engineering and economic ones. The engineering aspect involves the manufacturing of compressed air with the required quality features and in the amount balancing its demand, whilst the economic aspect is associated with cost minimisation. This paper investigates the engineering aspects: air quality, with the main focus on air treatment processes to satisfy the constructional and operational requirements of air receivers present in the casting processes.

In this article the main problems related with the proper choice of the design and operation parameters of vacuum installation in vacuum moulding system have been discussed. In such system a vacuum are generated using electric-driven vacuum pumps. The aim of the experiment is to evaluate the performance of a vacuum system basing on registered plots of selected electric power parameters of the power-supplying system of the pumps with parallel measurements instantaneous values of pressure in selected points of model stand. The measurements system for power-supply unit has incorporated the recorders of instantaneous current and voltage values. Following the suitable numerical procedure, the experimental data are analysed to yield mathematical relationships between the variations of the generated vacuum pressure levels and variations of selected electric power parameters. According to the authors, the applied measurements system of the parameters of a vacuum-assisted installation may become an effective and easy practical method of evaluating the performance of such installations, used also in industry.

Investigations of operating parameters of widely used sand mixers reveal a wide variability range in the values of parameters associated with their power demand. Power efficiency of manufacturing processes has received a great deal of attention lately, which encourages the research efforts to optimise this aspects of operation of machines and installations as well. In the first place these machines and installations have to work properly as a part of the process line- which applies also to moulding sand mixers. Experiments conducted by the authors suggest that the same goal can be achieved at variable energy input levels. To obtain information about the power demands of sand mixers requires the use of highly specialised equipment, methodology and result processing procedures. This study provides a brief characteristic of measurement equipment and results of measurements taken on a unit AG-015 (based on a roller mixer) and a laboratory rotor mixer.

The paper outlines the methodology of virtual design of a foundry plant as a system. The most important stage in the procedure involves the development of a model defined as a set of data about the system. Model development involves two stages: defining the model's architecture and specifying the model data in the form of parameters and input-output relationships. The structure is understood as configuration of machines and transport units, representing the sub-systems and system components. As the main purpose of the simulation procedure is to find the characteristics of the system's behaviour, the merits of the iterative method involving analysis, synthesis and evaluation of results are fully explored.