Fiber-reinforced plastic pipe

Fiber-reinforced plastic pipe (FRP) can be produced by rotating a mixture of chopped strand and catalysed resin inside a hollow mandrel. Because... 

Corrosion Resistant Fiber-Reinforced Plastic (FRP). Fiber glass reinforcement bonded with furfuryl alcohol thermosetting resias provides plastics with unique properties. Excellent resistance to corrosion and heat distortion coupled with low flame spread and low smoke emission are characteristics that make them valuable as laminating resins with fiber glass (75,76). Another valuable property of furan FRP is its strength at elevated temperature. Hand-layup, spray-up, and filament-win ding techniques are employed to produce an array of corrosion-resistant equipment, pipes, tanks, vats, ducts, scmbbers, stacks, and reaction vessels for industrial appHcations throughout the world. 

In the gas cleaning sections of spent acid or metaUurgical sulfuric acid plants, the weak acid scmbbing circuit is typicaUy handled by plastic or glass fiber reinforced plastic (ERP) pipe. The contaminants in weak acid usuaUy vary too greatly to aUow use of an economical aUoy. 

For firewater, steel pipes are used but corrosion products can block sprinklers. Cement asbestos pipes are utilized but pressure limitations restrict their use. For critical applications, including offshore oil installations, cupronickel alloys and even duplex stainless steels are used. Fire-retardant grades of fiber-reinforced plastics are now available. 

For calculation of flow in fire main systems, the design engineer should use the Hazen-Williams friction coefficient of C = 100 in the design of bare steel and concrete steel lined pipingforfire water systemsto allow for future deterioration as the system ages. A friction coefficient of C = 140 may be used for plastic pipe, such as fiber reinforced plastic (FRP) or polyvinyl chloride (PVC). 

Fiber reinforced plastics have seen much service in industry because of their excellent mechanical and chemical properties and also economical point of view. At present corrosion resistant fiber reinforced plastics are in use as large tanks, vessels, reactors and pipes. 

Appendix A contains a materials selection guide for aerated freshwater systems. As indicated in Note 27 of Appendix A, in freshwater systems, admiralty brass should be limited to a maximum pH value of 7.2 from ammonia and copper-nickel alloys and should not be used in waters containing more sulfides than 0.007 mg/L The materials selection guide is also satisfactory for seawater, although pump cases and impellers should be a suitable duplex stainless steel or nickel-aluminum-bronze (properly heat treated). Neoprene-lined water boxes should be considered. For piping, fiber-reinforced plastic (up to 150 psi [1,035 kPa] operating pressure) and neoprene-lined steel should also be considered. Titanium and high-molybdenum SS tubes should be considered where low maintenance is required or the cost can be justified by life expectancy. 

While the previously described three membrane modules required flat sheet membrane material for their preparation, special membrane configurations are needed for the preparation of the tubular, capillary, and hollow fiber modules. The tubular membrane module consists of membrane tubes placed into porous stainless steel or fiber glass reinforced plastic pipes. The pressurized feed solution flows down the tube bore and the permeate is collected on the outer side of the porous support pipe, as indicated in Figure 1.33 (d). The diameters of tubular membranes are typically between 1-2.5 cm. In some modules, the membranes are cast directly on the porous pipes and in others they are prepared separately as tubes and then installed into the support pipes. 

In the context of corrosion, composites refer to glass or other fiber or flake-reinforced thermosetting resins. Composite products use for their anticorrosion properties are fiberglass-reinforced pipe and storage tanks, fiber-reinforced plastic grating, handrails, I-beams, and other shapes equal to these that are made of steel. 

Indirect Contact. Direct contact was more popular in the past, when none of the common construction metals was resistant to chlorine. Typical materials of construction were thermosets (such as a phenolic resin reinforced with asbestos) for vessels and stoneware or glass for piping. This situation changed with improvements in fiber-reinforced plastic fabrication and the commercial advent of titanium. The indirect-contact approach has now become a standard. The typical chlorine cooler today is a single-pass vertical shell-and-tube exchanger with titanium tubes and tube sheets and a carbon steel shell (or perhaps FRF in smaller units). Construction of tube sheets may be of solid titanium, or they may be clad or explosion-bonded with titanium. The inlet channel to the primary cooler also may be of titanium the other channels usually are of FRR... 

Sims et al. [25] reviewed some UK contributions to the development of fiber-reinforced plastics such as those used for glass-reinforced plastic pressure vessels and pipes. He also discussed the need for harmonizing and validating the many variants of property testing methods currently in use. 

The Deutsche Institut fiir Bautechnik (DIBt) publishes a media list for glass fiber reinforced plastic laminates made from UP/PHA resins [7] that provides proven minimum properties according to DIBt requirements for issuing certifications for containers, retaining devices and pipes. Appendix Tables A.49 to A.54. 

Uses. About 60% of the MA produced is used to make unsaturated polyester and aikyd resins, which are formed by reaction of MA with glycols. Polyester resins are used in the fabrication of glass fiber reinforced parts. Applications include boat hulls, automobile body parts, patio furniture, shower stalls, and pipe. Aikyd resins are mostly used in coatings (paint, varnish, lacquers, and enamels). MA also is widely used as a chemical intermediate in the manufacture of plasticizers and dibasic acids (fumaric, maleic, and succinic). About 15% of MA production goes into the manufacture of viscosity index improvers and dispersants used as additives in lube oils. Several agricultural chemicals are based on maleic anhydride, the best known being Malathion. 

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