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This paper completes a design of power monitoring system of machine tool based on MSP430F149 microcontroller. This system is mainly divided into four modules: the electric energy information input and processing module, electric energy metering operation processing module, Single-Chip Microcomputer system internal data processing module, and PC memory module, respectively. The voltage transformer and current transformer collect voltage signal and current signal respectively, which were inputted deferentially to the ATT7022A voltage channel and current channel, to achieve electric energy information input and processing. The special measure chip ATT7022A measures the three-phase active power, reactive power, apparent power, active energy and reactive energy to meter and operate electric energy. MCU system processing module communicates with ATT7022A chip via the SPI bus interface by using the 16 bit MSP430F149 microcontroller. The establishment of database model and database table using the relatively practical method of entity-relationship achieves PC internal data memory module. In addition, the fabrication of PCB circuit board and software writing are also introduced in detail in this paper.

This article deals with simulations of the welding process for applications of practice using SYSWELD software. Simulation of welding at the repair of high-pressure gas pipeline with steel sleeve with composite filling is presented in this paper. Two welds connecting the distance ring and gas pipe were simulated. Structure of programme SYSWELD and repair of high pressure gas pipeline with steel sleeve is described in theoretical part of article. Preparation of boundary conditions for numerical simulation on real sample and numerical simulation of welding is in experimental part. Thermal fields, residual stresses and hardness were simulated. The results of the numerical model, which are listed in article except for residual stresses are compared to real experiments. This article mainly describes the numerical simulation capabilities in welding simulation programme SYSWELD.

The article describes typical damage of rolling bearings and basic methods of their detection. From various methods of working bearings diagnosis the vibration method selected. Vibration signal contains a series of important technical information about the machine condition and is currently the most frequently used in diagnostic bearings systems. Furthermore, structure of vibroacoustic signal the frequency generated by the damaged bearing depends on the causes of the damage, the phases of its development and in particular the size of signals from other kinematic nodes, load, service quality and environmental impact. Monitoring the dynamic state of bearings nodes can carry out repairs technical conditioned by state of machines and omission preventive repairs conditioned by time and emergency repairs. In addition, the article describes the classification of bearing damage according to ISO standards, which identified the mechanisms related to the formation of any type of damage.

The article deals with cyclical abrasive wear of the surface of forming tools. At this stage the research focused on the genesis of stress in the contact between a deformed material and a tool in the cold bulk forming process. The experiments were conducted in the simple configuration of the upsetting test. The article presents the results of abrasive wear by a combination of materials of examined samples and upsetting plates. The abrasive wear in the used material specimens was analysed comparatively in the form of the wear factor by the finite element method. Two intersecting phenomenological fields represent the output for the examined material combinations. Firstly, it is a formulation of the dependencies of the maximum depth increase of the surface wear. The argument is the number of exposure cycles. At the same time, the topology of degradations and the resulting roughness in the space of the exposed surface were examined.

The purpose of this paper is to describe the area of risk management, in which maintenance can positively contribute to risk reduction and suggested reliability methods and maintenance tools can be used for risk treatment. The authors define the relationship between critical failure and risk and influence of preventive maintenance and redundancy on risk level. The risk level is defined as a product of critical failure probability and cost of critical failure losses. The proposed method enables to quantify risk treatment results. Benefits of the proposed risk treatment method based on preventive maintenance and redundancy applications are risk reduction and decreased costs (losses) of critical failure consequences within chemistry and nuclear power industrial technology. All decisions of maintenance have to be assessed according to economic criteria for specific objects and conditions in order to choose proper system maintenance.

Introduction into problems - It is expected that the measured value of the hardness will not be dependent on the applied test load and operators carried out the measurement. The Vickers hardness tester was calibrated by three operators using loads between 49.03 and 980.7 N and one CRM (standard) for a full load range. The uncertainty of obtained results was calculated in accord with standard ISO 6507-2 and tolerances analyze method. The capability of the calibration was evaluated by GRR method of the Measurement systems analysis (MSA). The method of total dispersion zone was used for estimation the impact of the variability between operators at particular loads on the measured value of the hardness. The influence of the load on the hardness expressed by Meyer's index "n" excluded ISE (indentation size effect). The influence of operators on the resultant hardness is weak, and the impact of applied load is ambiguous. The values of uncertainty calculated in accordance with the standard and by tolerance analysis are comparable.

The investigation of mechanical properties of aluminum alloys by using express-methods is discussed in the present paper. Such properties are hardness, elastic modulus E and yield strength Rp0.2. Tensile test with extensometer and automated ball indentation test (ABI) with 5 mm ball indenter performed in order to obtain the correlations for the basic mechanical properties of aluminum alloys. The results of newly developed method of revealing the microstructure, which involves plastic deformation, show its potential of applicability in engineering practice when measuring the microstructural and submicrostructural features.

This essay aims to identify the composite motion and the cutting force between the grinding wheel and roller of the roll grinder. Based on the analysis of roll grinding mechanism, this essay further uses Newton's law which describes linear motion and Euler equation which describes rotation to build rolling components' Newton-Euler dynamics equation. Then the essay simplifies rolling components' virtual prototype, and uses the dynamic analysis function of ADAMS to do dynamics simulation analysis of rolling components. Finally, based on the formula to calculate grinding force, this essay testifies that calculated results are consistent with simulation results, thus providing reference data for optimization.

The paper deals with capacitor discharge welding of aluminum studs type AlMg3 on two different materials (aluminum sheet of the same chemical composition with a thickness of 1.5 mm, and the magnesium sheet, material AZ61 and thickness 1 mm). Influences of welding parameters on the mechanical properties of the weld joints and the creation of typical defects were examined. For assessing the quality of weld joints, a series of tests were made: micro hardness test, bend test, torque test, test of macro and microstructure and SEM analysis on the electron microscope. The results are presented in the paper including suggestions for welded joints of required quality.

The paper presents application of Siemens RobotExpert software of industrial robot offline programming. The deburring process of aluminium wheel is described and developed. The robotic work-cell contains robot ABB IRB 1600id and two axes positioner ABB IRBP A 750 D 1000 H 700. The final robot tool path is checked using the collision viewer, the joint status monitor, the tool centre point speed viewer and tracker.

The final shape of machine parts is formed out by means of machining. At the machining the surface rises of definite properties, a given integrity, from these a surface usage comes out in the final machinery. This surface use is put especially its service life and loading capacity. The manufacturing watches the selected elements of the surface integrity for the functionality assurance of the machine parts. The machining influences in a different way the variant components. These are e.g. construction notches - the changeovers of single design components. The selection of a technology method of machining, the cutting tool at the finishing can affect notably both the function and service life of a machine part. The paper deals with the surface integrity at the surface load in machinery. There are the questions of the construction notches and next elements owing to the use of finishing method.