Utjecaj hibridnog kalupa na svojstva injekcijski prešanog plastomernog otpreska

doctoral thesis

• Title (english): Influence of the hybrid mould on the properties of the injection moulded thermoplastic part
• Author: Damir Godec
• Mentor: Mladen Šercer (mentor)
• Committee member: Igor Čatić (predsjednik povjerenstva)
• Committee member: Mladen Šercer (član povjerenstva)
• Committee member: Pero Raos (član povjerenstva)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2005-11-23, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering
• Universal decimal classification (UDC): 621 - Mechanical engineering. Nuclear technology. Machinery ; 678 - Industries based on macromolecular materials. Rubber industry. Plastics industry

Abstract

Tema disertacije je analiza utjecaja hibridnog (prototipnog) kalupa na svojstva plastomernog tankostjenog otpreska načinjenog injekcijskim prešanjem. Postupci brze izradbe kalupa omogučuju izradbu prototipnih kalupnih umetaka u vrlo kratkom vremenu; no uslijed razlike u svojstvima materijala tih umetaka i načinu njihove izradbe dolazi do odstupanja u svojstvima otpresaka u usporedbi s otprescima načinjenim u klasičnom kalupu. Stoga disertacija obuhvača usporednu analizu utjecaja oba kalupa na svojstva otpresaka i zavisne parametre preradbe. Računalna simulacija postupka klasičnog injekcijskog provjerena je kao učinkovit alat za predviđanje parametara preradbe te nekih svojstava otpresaka. Područje njene primjene pri tankostjenom injekcijskom prešanju nedovoljno je istraženo pa je u okviru rada analizirana njena primjenjivost u tom slučaju. S pomoču računalne simulacije predviđana su zbivanja u oba kalupa; te su definirani početni parametri preradbe za provedbu pokusa. S pomoču eksperimentalne analize utvrđen je utjecaj pojedinih parametara preradbe i vrste kalupnih umetaka na svojstva otpreska pri čemu su postignuta svojstva otpresaka načinjenih u hibridnim kalupu nešto niža u usporedbi sa svojstvima otpresaka načinjenih u klasičnom kalupu (deformacije otpresaka i rastezna žilavost). U cilju približavanja svojstava otpresaka načinjenih u hibridnom i klasičnom kalupu; provedeno je optimiranje signifikantnih nezavisno podesivih parametara u slučaju hibridnog kalupa. Rezultat optimiranja je bitno smanjenje početno postignutih razlika u svojstvima otpresaka. Eksperimentalna analiza također je omogučila uvid u primjenjivost računalne simulacije za tankostjeno injekcijsko prešanje u klasičnom i hibridnom kalupu. Opčenito simulacija rezultira zadovoljavajučim rezultatima osim pri predviđanju deformacija otpreska. Disertacija je obuhvatila i analizu osjetljivosti oba kalupa na zastoje u radu; pri čemu se kao neznatno osjetljivijim pokazao hibridni kalup.

Abstract (english)

The subject of thesis is analysis of influence of hybrid (prototype) mould on thin-wall thermoplastic moulded part produced by injection moulding. Rapid Tooling procedures enable manufacturing of mould inserts in very short time; but due to differences in material properties of these inserts as well as in the way of their manufacturing there are certain deviations in moulded parts properties in comparison with moulded parts produced in classical mould. Therefore thesis emphasizes compared analysis of influence of both moulds on moulded part properties and dependent processing parameters. Computer simulation of classical injection moulding process has already been proved as very useful tool for prediction of processing parameters and some moulded part properties. Field of application of simulation in case of thinwall injection moulding has not been enough investigated yet; so the analysis of its application in this field was performed in the thesis. Computer simulation was used for prediction of occurrences in both moulds as well as for definition of initial processing parameters. Experimental analysis was used for determination of influence of single injection moulding parameter on moulded part properties. Analysis has shown that application of hybrid mould results with lower moulded part properties in comparison with properties of moulded parts produced in classical mould (moulded part deformation and impact resistance). In order to make moulded parts properties produced in hybrid mould closer to those produced in classical mould; in case of hybrid mould an optimization of significant independent adjustable processing parameters has been performed. Optimization results with obvious decreasing of initial moulded parts properties differences. Experimental analysis also enabled review of applicability of computer simulation for thin-wall injection moulding in classic and hybrid mould. Generally simulation results with satisfactory data except in prediction of moulded part deformation. Thesis also emphasizes analysis of sensitivity of both mould types on delays during mould operation. Hybrid mould was recognized as slightly more sensitive in comparison with classic mould.

• Keywords: injekcijsko prešanje plastomera; tankostjeno injekcijsko prešanje; brza izradba prototipova; brza izradba kalupa; hibridni kalup; računalna simulacija; eksperimentalna analiza
• Keywords (english): injection moulding of thermoplastics; thin-wall injection moulding; rapid prototyping; rapid tooling; hybrid mould; computer simulation; experimental analysis
• Language: croatian
• URN:NBN: urn:nbn:hr:235:616066
• Study programme: Title: Mechanical Engineering and Naval Architecture; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje tehničkih znanosti (doktor/doktorica znanosti, područje tehničkih znanosti)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2020-12-03 07:53:20