Development of a cavity pressure control for injection moulding by adjusting the cross-section in the hot runner
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Christian Hopmann
and
Hanna Dornebusch
Abstract
Fluctuations in the injection moulding process are affecting component quality. A pressure control can be used to increase process consistency. However, current control systems cannot influence the melt flow in the mould specifically for individual cavities. Therefore, a control concept is being developed in which commercially available, servo-electrically driven hot runner valve pins are used to control the cavity pressure in the holding pressure phase. By varying the stroke, the pressure resistance in the hot runner and thus the pressure transfer into the cavity are influenced. A one cavity mould with two pressure sensors and a servo-electrical driven hot runner was used to evaluate the control setup, implementing a PID controller. The evaluation criterion for the setup is to what extent the reference curve measured in advance can be reproduced after provoked disturbance. The control calculates the difference between the actual pressure and the reference curve. The control compensates the pressure difference by a pin movement. The control concept can compensate for disturbances that do not change the material behaviour, such as changes in holding pressure. Changes in the material behaviour, for example due to fluctuations in the mould temperature, cannot be compensated due to the reference control.
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Author contribution: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
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Research funding: The research project 19966N of the Forschungsvereinigung Kunststoffverarbeitung was sponsored as part of “industrielle Gemeinschaftsforschung und -entwicklung (IGF)” by the German Bundesministerium für Wirtschaft und Energie (BMWi) due to an enactment of the German Bundestag through the AiF. We would like to extend our thanks to all organizations mentioned.
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Conflict of interest statement: The authors declare no conflicts of interest regarding this article.
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© 2022 Walter de Gruyter GmbH, Berlin/Boston
Articles in the same Issue
- Frontmatter
- Material Properties
- Advancement in hemp fibre polymer composites: a comprehensive review
- Effects and mechanism of filler content on thermal conductivity of composites: a case study on plasticized polyvinyl chloride/graphite composites
- Effects of Eucommia ulmoides gum content and processing conditions on damping properties of E. ulmoides gum/nitrile-butadiene rubber nanocomposites
- Preparation and Assembly
- Preparation of flame retardant glass fiber via emulsion impregnation and application in polyamide 6
- Invertase adsorption with polymers functionalized by aspartic acid
- Engineering and Processing
- External field alignment of nickel-coated carbon fiber/PDMS composite for biological monitoring with high sensitivity
- Development of a cavity pressure control for injection moulding by adjusting the cross-section in the hot runner
- Process optimization for extraction of avian eggshell membrane derived collagen for tissue engineering applications
- Joint formation mechanism of different laser transmission welding paths
Articles in the same Issue
- Frontmatter
- Material Properties
- Advancement in hemp fibre polymer composites: a comprehensive review
- Effects and mechanism of filler content on thermal conductivity of composites: a case study on plasticized polyvinyl chloride/graphite composites
- Effects of Eucommia ulmoides gum content and processing conditions on damping properties of E. ulmoides gum/nitrile-butadiene rubber nanocomposites
- Preparation and Assembly
- Preparation of flame retardant glass fiber via emulsion impregnation and application in polyamide 6
- Invertase adsorption with polymers functionalized by aspartic acid
- Engineering and Processing
- External field alignment of nickel-coated carbon fiber/PDMS composite for biological monitoring with high sensitivity
- Development of a cavity pressure control for injection moulding by adjusting the cross-section in the hot runner
- Process optimization for extraction of avian eggshell membrane derived collagen for tissue engineering applications
- Joint formation mechanism of different laser transmission welding paths
