Continuous fiberglass-reinforced

Another method of manufacture of solid-wall pipe is to extrude and wrap molten sheets or strips of thermoplastic around the outside surface of a tubular mandrel. Where this method is used, this pipe is manufactured to a controlled inside diameter. Continuous fiberglass-reinforced thermosetting resin pipe is generally manufactured in this manner. Some types of spiral-strip-wound composite piping are manufactured by being formed against the inside surface of a tubular fixture. 

Tanks made from fiberglass-reinforced plastic are being increasingly used, but a number of failures have occurred. In the United Kingdom 30 catastrophic failures are known to have occurred during the period 1973-1980, and a 1996 report shows that they seem to have been continuing at a similar rate [21J. The following typify the catastrophic failures that have occurred [11] ... 

Hanak et al (9) presented a paper regarding the use of propoxylated Mannich adducts for the production of continuous laminates and fiberglass-reinforced molded rigid foam characterized by CFC reduction or elimination. Table 46 shows an example of the formulation and process conditions employed (9). 

Pultrusion. Another method by which thermoplastic fiber-reinforced polymers are produced is pultrusion. In pultrusion, an appropriately designed bundle of continuous fiber strands is drawn through a die along with a molten thermoplastic matrix material. The die serves to consolidate the material combination, and as the matrix material solidifies on exiting the die, a continuous fiber-reinforced structure is produced. Examples of pultruded products include fiberglass rods and reinforced water hoses. 

As also seen in earlier chapters, fiberglass reinforcements can be obtained in various forms, such as continuous roving, woven roving and chop-strand mats. The choice of configuration would largely depend on the selected... 

TABLE 1.12 FIBERGLASS REINFORCED EPOXY AND VINYL ESTER PIPING SYSTEMS-A.O. SMITH-INLAND (continued)... 

TABLE 1.14 FIBERGLASS REINFORCED ISOPHTHALIC POLYESTER AND VINYL ESTER-MORRISON MOLDED FIBER GLASS (continued)... 

By far the most common form of reinforcement is fiberglass. Products using unsaturated polyester resin as a matrix and fiberglass fiber reinforcements are commonly referred to as composites , laminates or FRPs (fiber-reinforced plastics). The latter reinforcements are sold as continuous roving, which is continuously chopped in place with a liquid resin stream, chopped roving mat, woven... 

While further work is continuing with quartz fabric, the data reported here and elsewhere(4,7) indicates that all other factors being equal, a quartz fabric reinforced laminate will produce TCEs that are higher than if Kevlar fabric were used. Further work is also indicated in the general area of hybrid fabrics such as combinations of Kevlar/fiberglass and Kevlar/quartz. 

Most commercial SRIM applications have been in general industry or in the automotive industry. The reinforcement material most commonly used has been fiberglass, due to the low cost. Fiberglass has been used in the form of woven cloth, continuous strand mat, or chopped glass. 

In addition to being available as continuous filaments and staple fibers in mats, fiberglass textiles are also available as biaxial, triaxial, knitted and three dimensional braided patterns. Many different resin matrices are in use but the emphasis in this chapter will be on unsaturated polyester and epoxy resins. While the strength and stiffness are controlled primarily by the reinforcements, the resinous matrix contributes to thermal conductivity and flexibility. The ultimate properties of these composites are based on a harmonious contribution of both the continuous and discontinuous phases. 

Table 2.27 Properties of Polyester Composites Reinforced by Continuous and Chopped Fiberglass...

Figure 1. Direct melt process for the production of continuous glass fibers. Redrawn from J. F. Dockum, Fiberglass, in Handbook of reinforcements for plastics, J. V. Milewski and H. S. Katz, Editors, 233-286, Van Nostrand Reinhold, New York, NY (1987).

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