Improvement of handle grip using reverse engineering, CAE and Rapid Prototyping

The overwhelming majority of manual operations is even nowadays performed by using manual hand tools. These tools can be divided into 2 groups hand tools designed for general use or a single-purpose hand tools for special operations. Tool described in this paper is used in assembling operation in the completion of electric motor. During the design of the existing tools the requirements for a functional part of the tool (lifespan, inability to damage the engine installation) were fully considered, demands for ergonomic grip area, however, were not taken into account. Long-term use of incorrectly designed tool causes carpal tunnel syndrome, hand-arm vibration syndrome, diminished sensitivity or tingling in the fingers of workers. These difficulties can be reduced or entirely eliminated due to proper design of the grip of hand tool. Most authors focus on adjusting the grip for optimum ergonomics at individual types of grips (cylindrical, palmar, lateral, etc.). However, as already mentioned, there are tools for specific operations when the working area is limited by space or a specific type of load on the grip is needed. In some cases, it is often necessary to change the type of grip or combine different types of grips. This paper describes the design of an optimal grip of hand tool used for specific operation when assembling motors. Design of prototype mold and production of functional prototypes for ergonomics assessment directly in the workplace were realized. New design of handle should reduce the risk primarily of developing carpal tunnel in long-term use.TBU in Zlin [IGA/FT/2016/010]; Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme [L01303 (MSMT-7778/2014)]; European Regional Development Fund under the project CEBIATech [CZ.1.05/2.1.00/03.0089

Nano-hardness of electron beam irradiated polyamide 11

Cross-linking is a process in which polymer chains are associated through chemical bonds. Radiation, which penetrated through specimens and reacted with the cross-linking agent, gradually formed cross-linking (3D net), first in the surface layer and then in the total volume, which resulted in considerable changes in specimen behaviour. In this study there was found that ionizing beta radiation increased the nano-mechanical properties of polyamide 11 (PA11). The measurement results indicated that ionizing beta radiation (66kGy, 132kGy and 198kGy) was a very effective tool for improvement of indentation hardness, indentation modulus, indentation creep and deformation works of studied polymers. The best results were achieved by irradiation at doses of 132 kGy (increase about 40%) by which the highest nano-mechanical properties of PA11 were achieved.TBU in Zlin [IGA/FT/2016/010]; Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme [L01303, (MSMT-7778/2014)]; European Regional Development Fund under the project CEBIATech [CZ.1.05/2.1.00/03.0089

Local mechanical properties of irradiated cross-linked HDPE

Using high doses of beta radiation for high-density polyethylene (HDPE) and its influence on the changes in the micromechanical properties of the surface layer has not been studied in detail so far. Specimens of HDPE were made with the injectionmoulding technology and irradiated with high doses of beta radiation (0, 132, 165 and 198) kGy. The changes in the micromechanical properties of the surface layer were evaluated using an ultra nano-hardness test. The results of the measurements showed a considerable increase in the micromechanical properties (indentation hardness, indentation elastic modulus) when high doses of beta radiation are used. The aim of this paper is to study the effect of ionizing radiation at different doses on the ultra nano-hardness of the surface layer of HDPE and compare these results with those for non-irradiated samples. The study was carried out due to the ever-growing use of this type of polymer HDPE.BGS, Biogeoscience Institute, University of Calgary; MEYS, Ministry of Education, Youth and Science; MSMT-7778/2014, National Landcare Programme; LO1303, National Landcare Programme; CEBIA-Tech, ERDF, European Regional Development Fund; CZ.1.05/2.1.00/03.0089, ERDF, European Regional Development FundTBU in Zlin [IGA/FT/2017/010]; Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme [LO1303 (MSMT-7778/2014)]; European Regional Development Fund under project CEBIA-Tech [CZ.1.05/2.1.00/03.0089

The Influence of runner system on production of injection molds

This experimental study describes the influence of runner system on rheological properties during the injection molding process. Economic effects on the amount of production are discussed as well. Autodesk Moldflow Synergy 2016 (Moldflow) was used for the study of the injection process. Three suggestions of the runner system, cold runner system, hot runner system and the combination of cold hot runner system have been promoted. These three variants underwent the rheological and economic analysis. As a result, recommendations for the application of the runner system for the required amount of production have been suggested.Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme [LO1303 (MSMT-7778/2014)]; European Regional Development Fund under the project CEBIA-Tech [CZ.1.05/2.1.00/03.0089]; TBU in Zlin [IGA/FT/2016/010

Effect of ionizing beta radiation on the mechanical properties of poly(ethylene) under thermal stress

It was found in this study, that ionizing beta radiation has a positive effect on the mechanical properties of poly(ethylene). In recent years, there have been increasing requirements for quality and cost effectiveness of manufactured products in all areas of industrial production. These requirements are best met with the polymeric materials, which have many advantages in comparison to traditional materials. The main advantages of polymer materials are especially in their ease of processability, availability, and price of the raw materials. Radiation crosslinking is one of the ways to give the conventional plastics mechanical, thermal, and chemical properties of expensive and highly resistant construction polymers. Several types of ionizing radiation are used for crosslinking of polymers. Each of them has special characteristics. Electron beta and photon gamma radiation are used the most frequently. The great advantage is that the crosslinking occurs after the manufacturing process at normal temperature and pressure. The main purpose of this paper has been to determine the effect of ionizing beta radiation on the tensile modulus, strength and elongation of low and high density polyethylene (LDPE and HDPE). These properties were examined in dependence on the dosage of the ionizing beta radiation (non-irradiated samples and those irradiated by dosage 99 kGy were compared) and on the test temperature. Radiation cross-linking of LDPE and HDPE results in increased tensile strength and modulus, and decreased of elongation. The measured results indicate that ionizing beta radiation treatment is effective tool for improvement of mechanical properties of LDPE and HDPE under thermal stress.TBU in Zlin [IGA/FT/2016/010]; Ministry of Education, Youth and Sports of the Czech Republic [LO1303 (MSMT-7778/2014)]; European Regional Development Fund under the project CEBIA-Tech [CZ.1.05/2.1.00/03.0089

Micro-hardness of PBT influenced by beta radiation

Cross-linking is a process in which polymer chains are associated through chemical bonds. Radiation, which penetrated through specimens and reacted with the cross-linking agent, gradually formed cross-linking (3D net), first in the surface layer and then in the total volume, which resulted in considerable changes in specimen behaviour. This research paper deals with the utilization of electron beam irradiated PBT on the micro-indentation test. Radiation doses of 66, 132 and 198 kGy were used for unfilled PBT with the 5% crosslinking agent (triallyl isocyanurate). Individual radiation doses caused structural and micro-mechanical changes which have a significant effect on the final properties of the PBT tested. The highest values of micro-mechanical properties were reached radiation dose of 132 kGy, when the micro-mechanical values increased by about 30%.TBU in Zlin [IGA/FT/2016/010]; Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme [LO1303 (MSMT-7778/2014)]; European Regional Development Fund under the project CEBIA-Tech [CZ.1.05/2.1.00/03.0089

Mechanical properties change of thermoplastic elastomer after using of different dosage of irradiation by beta rays

Radiation processing of polymers is a well-established and economical commercial method of precisely modifying the properties of polymers. The industrial applications of the radiation processing of plastics and composites include polymerization, cross-linking, degradation and grafting. Radiation processing mainly involves the use of electron beams from electron accelerators. The Thermoplastic Elastomer (TPE) was used in this research and the mechanical properties were investigated at the ambient temperature. Results demonstrate that TPE has higher values of tensile strength with the increased irradiation dose and it has decreased elongation at break. This behaviour leads to the expansion of these materials in the automotive and electrical industry.TBU in Zlin [IGA/FT/2016/010]; Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme [L01303 (MSMT-7778/2014)]; European Regional Development Fund under the project CEBIATech [CZ.1.05/2.1.00/03.0089

Mechanical properties of modified HDPE by ionizing radiation after temperature load under and above the pure HDPE melting temperature

Radiation processing of polymers is a well-established and economical commercial method of precisely modifying the properties of polymers, especially mechanical properties. The mechanical properties of modified HDPE samples by beta rays were measured at the ambient temperature and after temperature load under and above the pure HDPE melting temperature. The tested samples showed significant changes of mechanical behaviour before and after temperature load. From this point of view, new applications could also be seen in areas with service temperatures higher than their former melting point

Polymer fluidity influenced by type and amount of filler

Delivery of polymer melts into the mold cavity is the most important stage of the injection molding process. This paper shows the influence of cavity surface roughness and technological parameters on the flow length of polymers into mold cavity. Application of the measurement results may have significant influence on the production of shaping parts of the injection molds especially in changing the so far used processes and substituting them by less costly production processes which might increase the competitiveness of the tool producers and shorten the time between product plan and its implementation. This research focused into the influence of technological parameters on filling of the injection mold cavity and the flow length respectively.Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme [LO1303 (MSMT-7778/2014)]; European Regional Development Fund under the project CEBIA-Tech [CZ.1.05/2.1.00/03.0089]; TBU in Zlin [IGA/FT/2016/010

Mechanical properties and temperature stability of modified polybutylene terephthalate by beta rays

The presented article deals with the research of mechanical properties before and after temperature load and temperature stability of modified polybutylene terephthalate by radiation cross-linking. The mechanical properties were measured, at the ambient temperature, by the tensile test on samples which were non-irradiated and irradiated by different doses of the beta radiation and then were temperature loaded. Results demonstrate that PBT has higher values of tensile strength with the increased irradiation dose and it has decreased elongation at break sharply. The purpose of the article is to consider to what extent the irradiation process influences the resulting mechanical properties and temperature stability. The PBT tested showed significant improvement of temperature stability after irradiation. This behaviour leads to the expansion of these materials in the automotive and electrical industry.TBU in Zlin [IGA/FT/2016/010]; Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme [L01303 (MSMT-7778/2014)]; European Regional Development Fund under the project CEBIATech [CZ.1.05/2.1.00/03.0089]ERDF, European Regional Development Fund; CZ.1.05/2.1.00/03.0089, ERDF, European Regional Development Fun