Complexes hollow

Fig. 4.22 Stages in blow moulding of complex hollow container...

This process is adapted to the realization of complex, hollow or solid sections, with high mechanical characteristics thanks to the high unidirectional reinforcement levels. 

Recently some interest in forming more complex hollow fibers has developed for example, composite hollow fibers in which the microporous shell of the fiber provides the mechanical strength, but the selective layer is a coating of a... 

Tsuyumoto, M. Karakane, H. Maeda, Y. Tsugaya, H. Development of polyion complex hollow fiber membrane for separation of water ethanol mixtures. Desalination 1991, 80, 139-158. 

Low tool and die cost rapid production rate ability to produce relatively complex hollow shapes in one piece. 

In pressure bag moulding, a positive air pressure (of several atmospheres) is used to inflate an elastomeric bag against the part while curing proceeds, which is mostly used for complex hollow shaped parts. Heat is often used to accelerate curing (Figure 9.7b). 

Extrusion blow molding is the process employed in the production of large containers such as drums, as well as complex automotive parts. This process is widely used to produce containers of various sizes and shapes. It is also adapted to make irregular, complex, hollow parts, such as those supplied to the automobiles, office automation equipment, and pharmaceutical sectors. In this process, the extrudates swell [5], as well as sag or draw down during parison extrusion stage. 

Blow molding Low tool and die costs complex hollow shapes possible rapid production rates Limited to hollow shapes tolerances hard to control... 

The basic fusible-core technique, a take-off of cored metal casting, makes it possible to produce simple to very complex hollow structural products. It involves using a fusible core inside the plastic part or structure. This core permits forming the desired plastic shape. The core material is a type that will not collapse or change shape during a pressure-temperature-time processing cycle. Shape is not usually the problem, since the core material is restricted. 

Ideal non-tank applications for rotational molding are typically complex hollow forms in relatively low quantities (up to approximately 10,000 parts). There are obvious exceptions to this, for example children s toys. But for the most part, rotomolding offers benefits to end-users with low upfront costs in tooling and equipment and the ability to render almost any design that the molder can conceive. 

Advantages. Blow molding is an extremely versatile process that can be used to produce moderately complex hollow-shaped parts that are truly three dimensional in shape. Small, hollow parts can be produced with great precision quickly using the injection molding process, while large, complex parts can be manufactured by EBM. 

Blow moulding Complex (hollow) Bottles Inflation Closed... 

Regardless of the injection process, the molds can be complex systems comprising many parts and moving pieces. In addition to the parts of the mold defining the external form of the product to be manufactured, a mold also includes ejectors to separate and evacuate the injection molded product as well as the cores used to obtain relatively complex hollow forms. 

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