Manufacturing and Rheological Analysis of Spiral Flow Test Piece
Gebrehiwot, Silas (2014)
Gebrehiwot, Silas
Arcada - Nylands svenska yrkeshögskola
2014
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Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:amk-201405158025
https://urn.fi/URN:NBN:fi:amk-201405158025
Tiivistelmä
The spiral flow test is one of the many tests that help to determine the rheological nature of plastics. It is such an important testing method as compared to different testing methods for its help in determining the most critical physical properties of a plastic. The thesis writing is made based on the combination of different course taught in Arcada along with many primary sources focusing on engineering and design of a mould. The spiral flow testing mould is developed with a basic formulation of an Archimedean spiral length. The development of the mould set would be done with the 3D modelling software (SolidWorks). The design is made based on plate standard developed by Hasco. The design of the cavity would have a 4, 25 revolution lengths with a channel diameter of 6 mm. The scope of the thesis is not limited to the design only; rather it actually goes until the complete production of the mould set. Hence, Mastercam simulation would also be made to actually mill the mould plates on the Haas CNC machine in the material science laboratory. The thesis also focuses on doing a virtual injection on Moldflow simulation to reduce manufacturing error and make adjustments before actual part making.
Rheological properties mainly focus on a shear viscosity of a molten plastic flow. It is quite a dynamic behaviour that could change with the change in temperature, pressure and injection speed. The thesis would calculate power law index constant for a specific polymer type of Luponen 1840 H LDPE on practical injection process. All of the viscosity analyses performed are based on spiral flow length of plastic travelled under specific operation conditions. Finally, there would be a comparison made between a theoretical formulation, Moldflow simulation and actual injection processes conducted under varying parameters. The thesis would also scientifically explain the reasons for variations.
Rheological properties mainly focus on a shear viscosity of a molten plastic flow. It is quite a dynamic behaviour that could change with the change in temperature, pressure and injection speed. The thesis would calculate power law index constant for a specific polymer type of Luponen 1840 H LDPE on practical injection process. All of the viscosity analyses performed are based on spiral flow length of plastic travelled under specific operation conditions. Finally, there would be a comparison made between a theoretical formulation, Moldflow simulation and actual injection processes conducted under varying parameters. The thesis would also scientifically explain the reasons for variations.