Accueil
Détail de l'indexation
Ouvrages de la bibliothèque en indexation 668.9
Ajouter le résultat dans votre panier Affiner la recherche
Visualization of flow instabilities for high density polyethylene / H. Kometani in INTERNATIONAL POLYMER PROCESSING, Vol. XXI, N° 1 (03/2006)
[article]
Titre : Visualization of flow instabilities for high density polyethylene Type de document : texte imprimé Auteurs : H. Kometani, Auteur ; T. Kanai, Auteur ; T. Suga, Auteur ; T. Matsumura, Auteur ; H. Kitajima, Auteur Année de publication : 2006 Article en page(s) : p. 32-40 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Polyéthylène haute densité
RhéologieIndex. décimale : 668.9 Polymères Résumé : Two typical flow instabilities of “Shark Skin” and “Melt Fracture” for high density polyethylene were investigated in this report. Experimental measurements were carried out methodically in a wide flow region from the reservoir (entry region) to the die land with a specific slit die. Especially the flow pattern was visualized with a high speed camera and the frequency of the flow instability was analyzed. Corresponding to the visualization analysis, the pressure fluctuation in the slit die and the surface roughness at the die exit were measured simultaneously and these frequency characteristics were analyzed with a FFT (Fast Fourier Transform) analyzer. As for “Shark Skin” region, the irregularity of the surface roughness in the broad frequency band was recognized at the die exit. In spite of this surface roughness, the pressure fluctuation and the fluctuation of the flow pattern at the wall vicinity in the die land were not observed.
These results indicate that “Shark Skin” occurs at the die exit. As for “Melt Fracture” region, the periodical oscillation of the flow pattern and the periodical pressure fluctuation which corresponded to the periodical distortion of the extrudate was recognized in the die land. However the periodical oscillation of the flow pattern and the periodical pressure fluctuation could not be recognized in the reservoir (entry region of the die land). These results indicate that “Melt Fracture” is initiated at the die entry and occurs in the die land. Consequently it is clarified that “Shark Skin” occurs at the die exit and the flow instability which lead to “Melt Fracture” is initiated at the die entry and occurs in the die land.DOI : 10.3139/217.0057 En ligne : https://drive.google.com/file/d/1JpHl1oJWg93Nc_BwHSAlDwFuiFkWjJsW/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=2927
in INTERNATIONAL POLYMER PROCESSING > Vol. XXI, N° 1 (03/2006) . - p. 32-40[article]Réservation
Réserver ce document
Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 003861 - Périodique Bibliothèque principale Documentaires Disponible Visualization of melt-flow behavior inside the runner in ultra high speed injection molding / S. Hasegawa in INTERNATIONAL POLYMER PROCESSING, Vol. XXI, N° 5 (11/2006)
[article]
Titre : Visualization of melt-flow behavior inside the runner in ultra high speed injection molding Type de document : texte imprimé Auteurs : S. Hasegawa, Auteur ; H. Yokoi, Auteur Année de publication : 2006 Article en page(s) : p. 464-472 Note générale : Bibliogr. Langues : Anglais (eng) Index. décimale : 668.9 Polymères Résumé : Ultra-high-speed injection molding is a highly effective technique for realizing very thin-walled molded parts; its application to the production of new high value-added products is anticipated. The melt-flow behavior in ultra-high-speed injection molding is expected to differ from that in conventional molding. However, thus far, very few studies pertaining to the phenomena occurring within cavities and runners at such high filling speeds have been reported, thus necessitating the direct observation of melt-flow behavior inside the molds. In this study, we attempted to dynamically visualize the meltflow behavior at the runner split portion, especially under ultra-high-speed injection molding. Visualization experiments were conducted using a glass-inserted mold, which was modified from the original visualization mold structure in order to improve the pressure endurance of the glass-inserted visible area. This paper discusses the visualization analyses of meltflow behavior in two types of experimental split runner systems (three inclined split runners and cross-shaped runners in a cascade layout). The behavior at the runner split area was studied under low to ultra-high-filling rates. The analyses clarified the effects of inertia at the runner branching point, which has not been verified in general injection molding, and the consequent changes in the filling behavior. DOI : https://doi.org/10.3139/217.0997 En ligne : https://drive.google.com/file/d/1SttkV178jpaTfR20bVuN3FeALuvqWQqu/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=2800
in INTERNATIONAL POLYMER PROCESSING > Vol. XXI, N° 5 (11/2006) . - p. 464-472[article]Réservation
Réserver ce document
Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 005699 - Périodique Bibliothèque principale Documentaires Disponible Warpage of film insert molded parts and optimum processing conditions / S. Y. Kim in INTERNATIONAL POLYMER PROCESSING, Vol. XXV, N° 2 (05/2010)
[article]
Titre : Warpage of film insert molded parts and optimum processing conditions Type de document : texte imprimé Auteurs : S. Y. Kim, Auteur ; S.-H. Lee, Auteur ; J. R. Youn, Auteur Année de publication : 2010 Article en page(s) : p. 109-117 Note générale : Bibliogr. Langues : Anglais (eng) Index. décimale : 668.9 Polymères Résumé : Three dimensional flow and structural analyses were carried out for film insert injection molding in order to evaluate the warpage and long term viscoelastic deformation of the film insert molded (FIM) tensile specimen. The predicted warpage after ejection and annealing was utilized as the input to the orthogonal array in order to obtain priority of significant factors and optimum molding conditions. Various injection molding factors influenced the degree of shrinkage of the injected substrate, i.e., packing pressure and mold wall temperature difference determined warpage of the FIM part after ejection. Warpage of the annealed FIM part was affected mainly by heat treatment conditions of the inserted film and annealing time of the part because annealing conditions had larger effects than the other processing factors. Optimum processing conditions and the relative significance of processing factors were obtained for warpage of FIM parts by using the Taguchi's method. Note de contenu : EXPERIMENTAL : Materials and characterization - Film insert injection molding.
NUMERICAL SIMULATION : FLow analysis of film insert molding - Viscoelastic stress-strain analysis.
TAGUCHI ANALYSIS
RESULTS AND DISCUSSION : Warpage after ejection - Wapage after annealing.DOI : 10.3139/217.2269 En ligne : https://drive.google.com/file/d/1vi3eh8JISu5QDzpCy7iI4KIVpLEMoSZi/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=9324
in INTERNATIONAL POLYMER PROCESSING > Vol. XXV, N° 2 (05/2010) . - p. 109-117[article]Réservation
Réserver ce document
Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 012158 - Périodique Bibliothèque principale Documentaires Disponible Water assisted injection molding : A review / S.-J. Liu in INTERNATIONAL POLYMER PROCESSING, Vol. XXIV, N° 4 (09/2009)
[article]
Titre : Water assisted injection molding : A review Type de document : texte imprimé Auteurs : S.-J. Liu, Auteur Année de publication : 2009 Article en page(s) : p. 315-325 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Matières plastiques -- Moulage par injection Index. décimale : 668.9 Polymères Résumé : Water assisted injection molding technology has become one of the most important methods to manufacture hollow plastic parts in recent years, due to its light weight, relatively lower resin cost per part and faster cycle time. This report aims to present a review of the development and progress of the water assisted injection molding technology. The tooling used for the process is introduced. The interaction between the assisting water and the polymer melt during molding is discussed, and insight into the penetration behaviors of the fluid is summarized. In addition, comparisons have been made between the gas-assisted injection molding and water assisted injection molding processes. DOI : 10.3139/217.2255 En ligne : https://drive.google.com/file/d/1Xccko1W-YbtdHAskJiaDr49uRaVyuqVe/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=6076
in INTERNATIONAL POLYMER PROCESSING > Vol. XXIV, N° 4 (09/2009) . - p. 315-325[article]Réservation
Réserver ce document
Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 011516 - Périodique Bibliothèque principale Documentaires Disponible Water penetration stability in water assisted injection molded symmetric ribs / S.-J. Liu in INTERNATIONAL POLYMER PROCESSING, Vol. XX, N° 4 (12/2005)
[article]
Titre : Water penetration stability in water assisted injection molded symmetric ribs Type de document : texte imprimé Auteurs : S.-J. Liu, Auteur ; P.-C. Lai, Auteur ; Y.-C. Wu, Auteur Année de publication : 2005 Article en page(s) : p. 352-359 Note générale : Bibliogr. Langues : Anglais (eng) Index. décimale : 668.9 Polymères Résumé : Water assisted injection molding technology has received extensive attention in recent years, due to its light weight, relatively lower resin cost per part, faster cycle time, and its flexibility in the design and manufacture of plastic parts. However, there are still some unsolved problems that confound the overall success of this technology. Unstable water penetration in molded symmetric channels is one of them. This report was to study the water penetration behavior in the water assisted injection molded symmetric cavity. Experiments were carried out on an 80-ton injection-molding machine equipped with a water injection unit. A plate cavity with symmetric water channels was used. The materials used were amorphous polystyrene and semi-crystalline polypropylene. Various processing variables were studied in terms of their influence on the water penetration behavior inside the symmetric parts: melt temperature, mold temperature, melt fill speed and fill pressure, shortshot size, water temperature and water pressure, and water injection delay time and water hold time. The effect of channel layout was also investigated. Tapered channels were found to mold parts with better penetration stability than flat channels. In addition, the penetration behaviors of water and gas in molded symmetric parts were also compared. The experimental results suggested that water penetration stability is more stable than that of gas in molded symmetric parts. Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=2960
in INTERNATIONAL POLYMER PROCESSING > Vol. XX, N° 4 (12/2005) . - p. 352-359[article]Réservation
Réserver ce document
Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 003422 - Périodique Bibliothèque principale Documentaires Disponible Wave behavior in the coating process of multilayer polymeric materials / Y.-Y. Su in INTERNATIONAL POLYMER PROCESSING, Vol. XIV, N° 1 (03/1999)
PermalinkWelcome to coatings college / Peter Mischke in EUROPEAN COATINGS JOURNAL (ECJ), N° 1-2/99 (01-02/1999)
PermalinkWeld line strength in PC/ABS injection moldings / T. Semba in INTERNATIONAL POLYMER PROCESSING, Vol. XIV, N° 4 (12/1999)
PermalinkWelding of plastics : fundamentals and new developments / D. Grewell in INTERNATIONAL POLYMER PROCESSING, Vol. XXII, N° 1 (03/2007)
PermalinkWire coating by drawdown of an extruded annular melt / J. C. Slattery in INTERNATIONAL POLYMER PROCESSING, Vol. XIV, N° 2 (06/1999)
PermalinkWonders of reduced phenolic resin / Mukund Hulyalkar in PAINTINDIA, Vol. LXI, N° 12 (12/2011)
PermalinkZinc surfactant effects on improved mechanical properties of silica-filled silicone rubber/natural rubber blends using TESPD coupling agent / T. T. Nga Dang in INTERNATIONAL POLYMER PROCESSING, Vol. XXIV, N° 4 (09/2009)
Permalink