Petr Baron

Sucking Machinery of Transport for Dosing Granulations of Plastics at Injection Molding

Advantageous properties of plastic materials, low investment costs for a production, cheap and productive processing method were given the rapid development of plastic materials. In this time injection molding technology is the most using technology for processing plastics in our country. Quality of the plastics processing depends mainly on the quality of material and preparing it for production. The first step in the processing of plastic by injection molding is dosing of granulations from hopper of injection machine unit. Task of this contribution is to theoretically describe a pneumatic method for transport of granulations in injection molding machine.

Optimization of the Production and Logistics Processes Based on Computer Simulation Tools

The decision-making process in the stage of technical preparation, during the planning of logistic portfolio and production queries is marked by individual decisions that may be affected by errors causing in extreme cases the fatal consequences. The tools of computer simulation help to eliminate the negative effects of bad decision-making. This article describes the usage of computer simulation in process of optimization of material flow using an appropriate spatial deployment of production facilities. The triangular method was used for the optimization of the spatial deployment. The factors to create the triangular method were obtained from the final report of the simulation of the current production state in the assessed facility. Subsequently a simulation of the proposed optimization variants was conducted. Based on the selected criteria, the most suitable alternative was chosen for the enterprise.

Implementation of Computer System for Support of Technological Preparation of Production for Technologies of Surface Processing

This paper describes attributes of newly designed variant approach of computer support system of technological preparation of production. Knowledge system for automation of production of technological documentation was developed for technology of surface processing of metal. The paper describes the design of coding system for sorting mechanical parts into groups with similar mechanical parts, either by their shape, dimensions or used technology. Subsequently, it points out to attribute of the system – uploading and modification of sample technological documentation.

Gate Location and its Impact to Flowing Characteristics of Plastic Moldings

Paper deals with simulation analysis of thermoplastic flowing in plastics product. As there is a demand in plastic products, plastic industries are growing in a fastest rate. Hence plastic injection molding process begins in manufacturing of complex shapes, in this process optimum gate location is one of the important criteria in mold design. Knowledge of ideal flow properties of thermoplastic materials give us a very good starting position for design of thermoplastics products which will be made by injection molding. By simulation software Plastic Advisor was compared injection parameters for the mold with varying gate locations. Simulated thermoplastic product is made from polycarbonate and is using for the drum washing machine as console window.

Proposal of the Knowledge Application Environment of Calculating Operational Parameters for Conventional Machining Technology

Calculation of the machining parameters is one of the basic routine operations carried out before initializing the work and technological operations on a machine tool. Basis for calculating these parameters is obtained from the technical documentation in the form of rules, tables, catalogues and company literature. It can be concluded that this is a routine activity which represents a significant proportion of the activities performed before actual production of the product. It is exactly the routine activities that are possible to underpin and process well with the help of computers and appropriate application equipment. This contribution describes the design and implementation of a knowledge based system of calculation of the processing and operational machining parameters with the possibility of parameter correction with regard to specific technological equipment. The result is the obtaining of an optimal machine setting for machined range of products with a consideration for the production efficiency, durability of the cutting tool and the possibility of reusing the archived operational parameters.

Microstructural Characteristics Investigation of the Chip-Making Process after Machining

Machining as a base technology for the manufacture of precision engineering components has a dominant position. Interaction of machine - tool - work piece has a significant impact on the quality of surface, next to under surface changes of worked material and finally to the total production process. In this work microstructures characteristics of the arising chip are evaluated depending on the defined conditions used for machining. Further basic patterns of the manufacturing process as well as the accompanying effects on the cutting process are clarified. Theory of formation of chip is not nearly closed part of the analytical theory of cutting indicates a possibility of further investigation boundaries of these zones of deformation, the application of mathematical, physical and other methods of examination, verification of modern experimental methods. Thickness of chip was achieved to 50 µm. This micro hardness value was selected to the plastic zones. In area of primary plastic deformation was in range from 256,7 to 264,0 HV 0,1. Area of secondary plastic deformation was higher as primary plastic deformation, it was in range of 289,4 to 357,4 HV 0,1. In plastic deformation area was in range from 261,5 to 278,2 HV 0,1 which is consequence of the action of the outgoing temperature

THE CORRELATION OF PARAMETERS MEASURED ON ROTARY MACHINE AFTER REPARATION OF DISREPAIR STATE

The article describes the application of tools of technical diagnostics of bearings in device for the production of cellulose due to previous difficult disorder of device. Diagnostics of bearings is a very challenging area of operational diagnostics. Bearing damage may be caused by various factors such as the action of excessive forces, unsuitable lubricant, contamination of the lubricant, the lubricant oxidation, degradation of additives, etc. Such factors can significantly reduce the lifetime of technical device. The measurements and expertises that took place, as described in the article, were based on the requirement of operators technical equipment to assess the trend of selected dynamic parameters, i.e. prediction of possibilities of risk of damage to the technical system in a short time. The measurement and subsequent identification of the real state of technical device has been performed in accordance with the recommendations of standard ISO 10816-3.

Monitoring of the Influence of Moisture Content in Thermoplastic Granulate on Rheological Properties of Material

Present article deals with assessing the influence of moisture content in thermoplastic material on rheological properties of material. The measurements were carried out on samples of hygroscopic plastics, i.e. plastics that tend to absorb moisture from the surrounding environment. Moisture in plastic material before its processing can have negative influence on physical or thermal properties of a product and can devalue visual aspect of the end product, thus these plastics have to be dried before their processing. Observed samples of materials were placed in three different rooms and measurements of Melt Volume-Flow Rate of thermoplastics were carried out at precisely determined intervals. Moisture content in material was determined by Mettler Toledo HB43-S moisture analyzer. To determine the influence of moisture content on rheological properties of material, a method of determination of Melt Volume-Flow Rate (MVR) of thermoplastics was used. The measurements were performed by using Termo Haake Meltflow MT etxrusion plastometer.

Research and analysis of stress distribution in multilayers of coated tools

Abstract The paper analyses stress distribution in mono/multi-layers of coated tools. It presents an analysis performed on mono-layer, double-layer and multi-layer coatings using numerical models to detect the developed stress distribution and the most stressed zones in these mostly 1–10 micron layers. With such thin layers, experimental detection of stress distribution would be very difficult. Moreover, coating thickness is distributed differently on flat surfaces from on shaped features in coated tools. This non-uniform coating results solely from the technology applied and such uneven deposition of the coating is critical in terms of how the tools themselves function. The paper provides an analysis of stresses in thinner or accumulated layers of coating on the rounded edge, for example in cutting. This analysis was initiated by ProTech Coating Service, Ltd., which manufactures physical vapour deposition coatings for cutting and forming tools.

MONITORING DIAGNOSTIC INDICATORS DURING OPERATION OF A PRINT MACHINE

This article deals with monitoring diagnostic indicators during the operation of a machine used for production of packing materials with a print. It analyses low-frequency vibrations measured in individual spherical roller bearings in eight print positions. The rollers in these positions have a different pressure based on positioning these rollers in relation to the central roller. As a result, the article also deals with a correlation of pressure and level of measured low-frequency vibrations. The speed of the print machine (the speed of a line in meters per minute) is a very important variable during its operation, this is why it is important to verify the values of vibrations in various speeds of the line, what can lead to revelation of one or more resonance areas. Moreover, it examines vibrations of the central roller drive and measurement of backlash of transmission cogs of this drive. Based on performed analyses recommendations for an operator of the machine have been conceived.