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The paper presents results of simulation of the end milling process. Simulation is based on nonlinear models of the mass-damping-spring system of the machine tool and a nonlinear model of the cutting process. Simulation investigations were performed using Matlab-Simulink. The apropropriate models were built on the basis of experiments. Results of calculation are compared with those obtained on the...
In the paper, an attempt was made to analyze an influence of the assumed input on dynamical properties of the model of a die forging hammer. Based on the technical specification, two calculation models of the hammer were built. The force acting dynamically on the hammer was determined. Consequently, numerical simulations were performed taking into account different variants of an input force. The...
In this paper an application of the genetic-fuzzy approach to the on-line control of transportation operation in flexible manufacturing systems is proposed. On-line control of transportation operation is understood here as the way of control in which a detailed algorithm of transportation operation is designed dynamically during the implementation of the production process on the basis of the concrete...
The paper presents empirical research objected to build model of transverse mold shrinkage for HDPE (high density polyethylene) molds with variable wall thickness. The model of fuzzy structure was elaborated. The model's independent variables: nominal mold's wall thickness, distance from the gate, packing pressure (constant profile) and the profile of mold thickness along direction of polymer flow...
Because of the dimensions of an adhesive bonded lap joint (with its length and width larger than its thickness) the literature on the subject provides us with many examples of simplification of the joint used in the finite element method (FEM). The simplification is based on discretization of the thin layer of an adhesive by the means of finite elements varying to a large degree as to the length of...
An impaired surface texture of the work-piece is a result of the chatter phenomena in machining. To remedy the problem various kinds of vibration absorbers have found a wide utility. In the paper three methods of control of a semi-active vibration absorber are compared. The first one is based on suboptimal pole and zero placement (PZP), the next one makes use of the model-following control (MFC) approach,...
The hydrogen to ammonia synthesis in the chemical plants is received in process of endothermic thermal-catalytic decomposition of methane with water steam. The process is carried out in reformer pipes made from austenitic cast steel with nickel catalyst under pressure up to 4.0 MPa and temperature up to 900 degrees C [1]. The long-lasting influence of raised temperature causes structural and phase...
Modern machining tools, which should be resistant to abrasive wear (possibility of the increase of the cutting speed) and to dynamics of machining (resistance to bending), have a great significance in terms of increase of productivity and quality of machining. One of the alternatives, fulfilling the expectations to a certain extent, are the bimetallic tools. Application of stratified bimetals for...
A problem of digital control of drives was discussed in this article. Digital controllers, like PLCs, introduce a delay that limits the application area of the traditional closed-loop control circuits to cases, where speed can be traded for accuracy or vice versa. On the other hand, the PLC-based control systems are cheaper than the dedicated high-speed axis controllers and provide a flexible platform...
The emergence of narrow-kerf technologies has encouraged scientists to conduct experimental studies of the effect of the kerf reduction upon specific cutting resistance (cutting pressure). An overall set (kerf), feed per tooth and saw blade thickness were input values in the carried out experiment. Therefore, besides changes of the total area of the cut, the effect of friction conditions between a...
The paper presents an investigation into the influence of cutting area cooling and lubrication on surface roughness, waviness, bearing ratio and the depth of surface layer changes in turning C45 steel. Cutting forces and their components together with chip formation and shape were put under examination too. The experimental results indicate that in the correctly selected cutting parameters elimination...
The objective of the work was determination of microstructural factors affecting deformability and fracture of 9-12% martensitic steels at room temperature and in the temperature range of hot processing. Effect of heat treatment upon structure, tensile and impact strength has been investigated. Microstructure constituents responsible for generating and propagation of cracks in the investigated steels...
The paper presents a methodological basis and an experimental method of determining static properties of subassemblies, such as sliding block and profiled guide rail. It also includes a description of a prototype of a test stand which was first designed and later produced. The authors demonstrate the results of their experiments carried out on some selected guideway subassemblies. The paper also contains...
Magnesium alloys are very attractive constructional material finding application in many fields of industry. However, they have also disadvantages like: low wear resistance, decrease of strength at high temperature, susceptibility to corrosion. In article the PACVD method of manufacturing of carbon layers on AZ31 magnesium alloy, fulfilling protective and decorative functions have been presented....
An impaired surface texture of the workpiece is a result of the chatter occurring in the process of machining. To remedy the problem, various kinds of vibration absorbers have found a wide utility. The paper presents the concept of a semi-active electrodynamic absorber of self-excited vibrations built around high-energy permanent magnets. Properties exhibited by the proposed absorber are compared...
The paper presents an investigations on the dynamics of valve seat machining. The goal of the study is ; agnose of the vibration type present during the process and evaluation of its influence on the tool life. Experimentally obtained frequency response functions (FRF) of the tool and workpiece are correlated with the vibration signal acquired during machining. Time-frequency analysis is then performed...
The paper presents a method of simulation design calculations of machine tools' systems containing rolling guideway connections. It shows how to model and determine static features of such objects. The authors present as an example design calculations for a lathe's tailstock system carried out in order to achieve an optimal - from the point of view of static features - version of construction. The...
A dynamics characteristic at the arc for evaluation of the process quality analyzing influence of electrode wire speed has been presented. Analysis of welding current and voltage value during the welding process allows to formulate the basic relations allowing for a line control the welding parameters. The control system is described by Unified Modeling Language (UML). The UML diagram may be used...
In the paper the model of microstructure of two phase titanium alloy was proposed to simulate its deformation behaviour in tension, taking into account different strength properties of a and ß phases. Deformation behaviour of the surface treated alloy was also studied. The alloy with and without diffusion strengthened layer and with hard elastic coating under tensile loading was modelled. The influence...
The issues of temperature measurements directly from a weld pool and a weld are discussed. Problems occurring while measuring with thermocouples are shown. The issues of thermal and derivative analysis are discussed. Thermal and derivative analysis applications to research into welding technology are reviewed.
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