Filament-wound pipe

The thermal stabiUty of epoxy phenol—novolak resins is useful in adhesives, stmctural and electrical laminates, coatings, castings, and encapsulations for elevated temperature service (Table 3). Filament-wound pipe and storage tanks, liners for pumps and other chemical process equipment, and corrosion-resistant coatings are typical appHcations using the chemically resistant properties of epoxy novolak resins. 

Their main applications have been in heat-resistant structural laminates, electrical laminates resistant to solder baths, chemical-resistant filament-wound pipe and high-temperature adhesives. 

RTR filament-wound pipe is, however, an anisotropic material. That is, its material properties, such as its modulus of elasticity and ultimate strength, are different in each of the principal directions of hoop and longitude. It is here where the design approaches for steel and RTR pipe part company [Fig. 4-2(c)]. This behavior is a result of the construction of filament-wound RTR pipe. 

The weep point or strain-to-first-crack in a wall for filament-wound pipe constructed using isophthalic plastic is currently found to be not less than 0.009 in./in. This has been repeatedly demonstrated by careful coupon testing and burst testing of pipes with strain gauge instrumentation attached. 

Uses. Production of methylene diphenyl diisocyanate (MDI), which is used to produce polyurethanes hardening agent for epoxy resins, anticorrosive materials, printed circuit parts, dyestuff intermediates, filament-wound pipe, and wire coatings... 

D.E.N. [Dow] Epoxy-novolac resin used in high-performance adhesives, structural and elec, laminates, potdng and molding compds., coatings and castings for elevated temp, service, and filament wound pipe. 

Perreux D, Joseph E. The effect of frequency on the fatigue performance of filament-wound pipes under biaxial loading experimental results and damage model. Compos Sci Technol 1997 57 353-64. 

The filament-wound pipe weep point is less than 0.009 in./in. The design is at a strain of 0.0018 in./in. providing a 5 to 1 safety factor. For transient design conditions a strain of 0.0030 in./in. is used providing a 3 to 1 safety factor. 

As reviewed, the mechanical properties of centrifugally molded pipe and 55° filament wound pipe are much more resin dependent than typical custom engineered pipe. With centrifugally cast pipe, the tensile properties are very resin dependent because the fibers are chopped into relatively short lengths. It is subjected to creep and time-loss of mechanical properties. In addition, resin properties drop radically with temperature especially near the glass transition temperature. 

Because of the excellent cooperation of a major oil company, buried oil field flow lines in Crane County, Texas are the most thoroughly documented application of fiberglass pipe. In 1961 and 1962 oil field flow lines in this major production area were installed using unlined aromatic amine cured epoxy, filament wound pipe. At that time, this type of pipe was a relatively new product, which had a good short term record as an economical solution to corrosion problems in oil field applications. Prior to the development of epoxy fiberglass pipe, cement lined steel with cathodic protection was the standard piping system for this type of oil field service. 

K J Oswald, Evaluation of epoxy and vinyl ester filament wound pipe removed from chemical and petroleum service. Managing Corrosion with Plastics, NACE, 1977, Volumes 1, 2, 3, pp 240-244. 

K J Oswald, The effects of chemical and petroleum service on epoxy and vinyl ester filament wound pipe . Paper 18, 18/1-18/8, NACE Corrosion 84, NACE, Houston, USA, 1984. 

Photopolymerizable epoxies using onium salt photoinitiators also show considerable promise for use in high performance composite applications. Traditional thermally cured epoxy resins are already well entrenched in these applications however, the use of the recently developed photocurable epoxy materials offers considerable potential for rapid fabrication of fiber-reinforced composites without the need for cumbersome ovens and long cure times. Photopolymerized epoxy laminates and filament wound pipe have already been demonstrated in our laboratory. 

Improved stress crack resistance Filament wound pipe... 

Anhydrides Good heat resistance good chemical resistance Long cure schedules at elevated temperature critical mix ratios Filament-wound pipe, electrical encapsulation, adhesives... 

Rousseau, J., Perreux, D. and Verdiere, N., The inlluenee of winding patterns on the damage behaviour of filament-wound pipes . Composites Science and Technology,... 

A bisphenol-A epoxy system, suitable for potable water contact, in for example the manufacture of filament wound pipes. Also suitable for laminates demanding high impact resistance, a. 1.16 c. 9-17Pa.s... 

The use and acceptance of buried large-diameter glass fiber, plastic reinforced, filament-wound pipe has increased steadily since the 1950s. Such RP was selected for its superior corrosion-resistance characteristics and installation-cost savings. ASTM standards use the term Reinforced Thermoset Resin Pipe (RTRP). Filament-wound pipe with a double helical angle of continuous-glass reinforcement (discussed later) is but one of several types of RTR pipe constructions. 

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