Blow molding optimization

Blow-molding processes consists of five main operations plastication of the resin, formation of the parison, inflation of the parison, solidification of the part, and removal of the part from the tooling. The best process economics will occur with a part optimized for weight and a minimum cycle time. In order to have a minimum cycle time, the cooling operation must be the rate-limiting step. For the case study... 

It is possible to blow mold several layers of material by coextrusion blow molding processes. By appropriate material selection, the various parts of the structure can be optimized for the best balance between properties and cost. 

Finally, it is worth mentioning the more recent three-dimensional blow molding in which a robot arm optimally positions the parison in the mold cavity, to minimize trim-off, and to produce complex shapes, such as automotive parts. 

Keener, C. et al., Optimizing Extrusion Blow Molding for Multilayer Container Production, Graham Machinery Group, York, PA, Aug. 15, 2001. 

Recent advances in polycarbonates include further enhancement of normally good fire resistance color elimination (an improvement approaching glass) and development of scratch-resistant coatings for glazing applications branched material for blow-molding bottles optimization of structural foam molding and compounds selective copolymerization and development of many different commercial polyblends. 

The low melt index grades of PPE blends with PS or HIPS Noryl , Luranyl ) are most suitable for blow molding. The optimal processing conditions depend on the article type and machine and thus should be experimentally optimized. The typical temperature range for parison extrusion is 250-260°C whereas it is 230-255°C for the adapter and accumulator. HOPE should be used for purging. 

The development of crystallinity may or may not be favorable depending on the end-use requirements of the PLA articles. For instance, high crystallinity will not be optimal for injection molded bottle preforms that are intended for further blow molding since rapid crystallization of the polymer would hamper the stretching of the preform and the optical clarity of the resulting bottle. In contrast, increased crystallinity will be desirable for injection molded articles for which good thermal stability is important. 

A 1 1 model is used as an intermediate stage. This can be helpful because the process development engineers are mostly inexperienced in blow molding and intermediate article optimizations (for process engineering and economic reasons). The model can be useful for blow molding because ... 

Also useful are simulation programs for the blow molding process [10]. These continuously optimized programs can be used as a form of expert system (e.g., the process engineering process is mathematically written and given to the program user). 3D molds and article data are necessary to use simulation programs. 

All three formulas may be injection molded and extruded into film and tubing, but only Ecdel elastomer 9967 can be extrusion blow molded. The melt temperatures generally range from 205 to 260°C. Optimization of the melt... 

Extensive modelling and computer-aided engineering (CAE) work was conducted to help optimize the blow molded seatback design. A prototype of the design was produced and tested for luggage retention and seat belt pull. The results were very encouraging and led to the development and successful introduction of the... 

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