Peter Pokorný

Optical 3D Scanning of Small Parts

The paper deals with the investigation of 3D digitizing of small parts specifically by optical 3D scanner GOM ATOS TripleScan. The paper shortly illustrates the general concept of Reverse Engineering, which includes also the 3D scanning. The paper also describes the optical 3D scanner GOM ATOS TripleScan and a three-dimensional model obtaining procedure by means of this scanner. In the main part of the paper the concrete 3D scanning process of chosen individual objects is described (clips, ball nose end mill, screw drill, coin). Their shape and size were specific and distinct, therefore it was possible to test and compare particular digitizing attributes. The problems that occurred during 3D digitizing of individual parts are step by step discussed and solved.

Analysis and Evaluation of Differences Dimensional Products of Production System

Logistics is primarily to address issues with whose functional, organizational, personnel and material means can be improved and optimize the entire course material flow businesses, which shall logistics integration business functions. Production logistics means a sum of logistical tasks and measures for preparation and execution of the production process. Includes all activities associated with material and information flows of raw materials, auxiliary and production materials from the warehouse to the production of raw materials and semi-finished goods from the warehouse and purchased parts through the various steps of the manufacturing process including all buffer stores, through the installation of the finished goods warehouse.

Optical 3D Scanning of Cutting Tools

The paper shortly illustrates the general concept of Reverse Engineering, which includesalso the 3D scanning. In the main part of the paper the concrete 3D scanning process of chosen individual objects are described. The problems that occurred during 3D digitizing of individual parts are step by step discussed and solved. The paper deals with 3D scanning of ball nose end mills and screw drill. The article gives a procedure for digitizing and comparing the results of the scanned digital models of the two ball nose end mills and screw drill.

Influence of Cutting Parameters on Achieved Geometric Tolerances in Rotary Ultrasonic Drilling of Al2O3

Submitted article deals with the impact of the cutting fluid´s pressure on the deviation from circularity. In submitted article an experiment is described when the pressure was changing from 15 to 25 bar in drilling of Al2O3 with ultrasound among other variables, feed and rotational speed. The aim of experiments was to define how the value of circularity of the hole is changing in different depths of machined hole. There is a dependence in USM process where the hole´s perimeter is rising with the depth of hole, however there was no knowledge in this problematics in RUM process. According to results from experiments it can be concluded, that the deviation from circularity is rising with the depth of a hole. The parameter influencing the deviation the most is cutting fluid´s pressure as was expected.

Reduction of Milling Time by Using CAQ Technologies

Abstract The paper is focused on reducing machining time by using 3D optical scanner of ATOS Triplescan II. Workpiece was a forging die, which was renovated by hard facing. The contribution deals with comparing the CAM simulation of roughing process according to the STL model imported from ATOS, and simulation without thus-defined workpiece. The results indicate a significant improvement of machining time based on CAQ technology and usage of the ATOS device for measuring the errors of weld deposit.

Estimation of Local Plastic Deformation in Cutting Zone during Turning

Local plastic deformation in cutting zone during turning is affected by technological conditions of the processes. Therefore it is needful to know detail structure changes of plastic deformed material during machining. It is localised, asymmetric deformation which operates at very large strains and exceptionally high strain rates. Three areas of intensive local plastic deformation in cutting zone were observed: the primary area of plastic deformation in shear plane, the secondary area of plastic deformation caused by friction of chip to tool face and the tertiary area of plastic deformation caused by friction of tool to machined surface. Local strain in these three areas was estimated by measurement of deformation of grains on metallographic cut. The effect of grains boundaries self-orientation caused by grains deformation was evaluated using stereology. But the orientation is not the same as deformation and so a correlation between the grain deformation and grain orientation was used. The turning piece was made of CK45 (1.0503) carbon steel. The specimen of cutting zone was obtained by using internal stress method.

Influence of Finish Milling Strategies on the Tool Wear

Abstract The article deals with the tool life of ball nose end mills during finish milling of weld deposit. The aim was to determine and compare the wear of ball nose end mill for different types of ball end milling strategies, as well as to specify particular steps of the measurement process. For tool life test, DMG DMU 85 monoBLOCK 5-axis CNC milling machine was used. In the experiment, the cutting speeds, feed rates, axial and radial depth of cut were constant. The coated cemented carbide was used as tool material. The cutting tool wear was measured on Zoller Genius 3s and laser Blum Micro Compact NT. The results show different achieved tool life of ball nose end mills depending on the finish milling strategy.

Deformation and FEM Analysis of the Chip Root in Face Milling Process

This paper was focused on analysis of deformation process in the chip root after milling of material C45. The aim of research was to evaluate the degree of deformation by using the method of oriented test lines. Experimental value of degree of deformation was compared to achieve in computer simulation of milling process in Deform software. The results from the chip root indicates of little differences between simulations and experimental obtained value of degree of deformation.

Finite Element Analysis of Tool Stresses, Temperature and Prediction of Cutting Forces in Turning Process

The paper presents the simulation model of turning the process of C45 non-alloy steel with a tool made of carbide insert. A 3D final element model used a lagrangian incremental type and re-meshing chip separation criterion was experimentally verified by measure cutting forces using piezoelectric dynamometer. In addition, stresses and temperature in the tooltip were predicted and examine. This work could investigate failure the tooltip, which would be great interest to predict wear and damage of cutting tool.

Design of Complex Component for Determination of a CNC Milling Machines Accuracy

The article is focused on the design of complex component to determine competence CNC milling machines designed to produce shapes with geometric tolerances by observing the shape, orientation and position of the standard EN ISO 1101. 3D model of a technological process for the production of complex components, it will contain the complete design of tools and cutting parameters for individual milling strategy, select clamping and workpiece material, a preview of the generated routing strategies and paths cut surface after each of their simulated. For milling machines with the so-called measurement system for machine OMM (On Machine Measurement), the proposal for a comprehensive parts serve as a reference in determining the accuracy of their measurements of geometric and dimensional tolerances. The main activity of systems OMM is the replace of the tool clamped in the spindle of milling machines with special touch probe which senses by the touch surface contours of produced parts.