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In the current manufacturing of foundry sand moulds, various methods of moulding sand compaction are used. Researchers are still looking for the optimal methods of mould manufacturing not only in terms of achieving the best technological effects, but also in terms of energy consumption. The article presents selected results of research of their own variant of the synthetic moulding sand compaction process using a vacuum. The measurements were also designed for evaluation the energy consumption in this method. The results were compared with other air flow moulding methods which are widely used. The study was performed on the original design test stand, which allows the visualization of the compaction process

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.

The rationalization of construction and vibro- fluidised bed coolers and turbine (rotary) mixers, allows for keep sufficiently high quality and increasing their utility values. This concerns optimization of construction and operation to increase the efficiency of their work. The presented research results illustrate a range of the work designed primarily to supplement theoretical foundations of realized processes in industrial devices, including the topics vibro- fluidization , evaporative cooling and refreshing mixing. Presented results concern the investigation of the industrial devices, which is difficult in the practical accomplishment. The part of testing was conducted in real terms of the functioning devices in the industry.

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.

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.

W artykule przedstawiono zarys zagadnień związanych z istotną problematyką energochłonności strumieniowych maszynformierskich. Zaprezentowano, wyniki badań oraz obliczeń parametrów niezbędnych do oszacowania energochłonności formierekstrumieniowych, uzupełnione również o analizę danych ofertowych producentów maszyn formierskich. Zwrócono uwagę nakonstrukcyjne i technologiczne czynniki sprzyjające zmniejszeniu energochłonności procesu formowania.

In this article, an outline of the key questions connected with the essential problems of energy-consumption of air-stream moulding machines has been presented. Research results and calculations of requisite parameters appraisable of energy-consumption of air-stream moulding machines have been supplemented also by the data analysis of offer of the moulding machines manufacturers. The attention on constructional and technological factors which are favourable for the diminution of energy-consuming of the moulding process has been paid.

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.

Process control plays a major role in supervision and identification of states, for example in monitoring of electric circuits power- supplying the foundry machines and devices, such as sand preparation processes, moulding technologies, melting, cleaning and finishing of castings. The monitoring and control equipment includes the power quality analysers. Testing is done using a Japanese analyser KEW 6319 (Kyoritsu) applied to monitoring of the sand preparation process in a foundry plant with low level of mechanization, equipped with the sand preparation unit based on a roller mixer.

The paper summarises the power measurement data for the main assemblies in a prototype turbine mixers for laboratory applications. Of particular interest are power demand signals in the paddle stirrer and the rotor. Tests were performed for the variable moisture content of the moulding sand containing bentonite. The process is described as dynamic and considered from the standpoint of automatics. Potential applications of the power demand signal are investigated in the context of the study of dynamics of the mixing processes, in terms of control of the water feeding to the moulding sand and for the purpose of evaluating the energy consumption.

The surface tension of foundry binders is a very important parameter affecting the properties of a sand-binder system. Combined with other parameters, its value determines an outcome of the process of moulding sand preparation and the mechanical properties of the ready moulding composition. The problem of how to measure the surface tension of binders used in preparation of moulding sands is discussed only occasionally. Indirectly, the surface tension is characterised by the value of a contact angle, but it never means that these two parameters can be considered identical. Numerous methods are available and used at present to measure the surface tension, among others, the capillary rise method, the spinning drop method, the sessile drop method, the pendant drop method, the method of pulled out ring (or plate, or frame). There is also a rich variety of devices offered with different measuring methods. The devices are modern and represent a high level of the technical skill and art. Unfortunately, also their price is high. It is, however, possible to obtain the reliable results of the surface tension measurement using relatively simple methods, viz. the stalagmometric method and the capillary rise method. What is necessary are proper conditions of the measurement, directly related with the specific properties of binders. The present paper gives examples of the results obtained during measurement of the surface tension of some selected binders. Attention was drawn to the methods of taking measurements, and the obtained results were discussed and analysed. The possibilities of detemining the surface tension of the examined binders from the results of the contact angle measurements using the “sessile drop” and “pendant drop” methods were outlined.

The paper addresses selected issues associated with the monitoring of the moulding sand preparation processes where the monitoring of power factors in the mixer drive is of primary importance. The study compares the indicators of electric power consumption by various types of mixers, summarizes the preliminary test data of power consumption in a paddle mixer drive. Process parameters were varied during the tests: moisture content and load. Coefficients and factors characterizing electric power demand are recalled. Two aspects of the monitoring system are considered to be of major importance: potential optimization of the mixing process in the function of energy consumption and control of the mixing process and its impacts on the properties of thus prepared moulding sand.

The study outlines the basic features of a newly-designed computer-supported system for monitoring and recording the instantaneous power consumption, used to control the operating parameters of foundry machinery. Explored are potential applications of the module for fast recording of instantaneous currents and voltages in a triple phase power supply system in a paddle mixer. Further research areas are indicated, to extend the system and the range of its potential applications.

Thc paper summarizes the selected results of tcsts pcrforrncd to find thc relationship bctwcca thc tcchnological and operational paramctcrsand power consumption by a mixcr drivc. Major tcchnological pammetcrs of moulding sand to considcr arc: mixing lime. moisturecontent. pan load. EIectric power demand is cxprcsscd by crfcctivc valucs, assuming thc bnlanccd tod. Thc propcrtics of moulding sandare shown to be correlated with pwcr factors. As thc mixing lcvcts changc, thc tcchnologicnl pararnacrs will chaagc, zoo and this Factmight bc utilized in monitoring of the mixing proccss. Thc pwcr factor of thc rnixcr drivc cos cp would vary considerably during themixer's operation under loading.