Piping reinforcements

Pipe reinforcement pads can be vented by intermittent rather than continuous welding, or a -in. or l4-in. hole can be drilled in the pad. 

Figure 7.5 shows a verification scheme that can be used for the analysis of a pipe reinforced with FRP. 

DESCRIPTION, CLASSIFICATION, AND TYPICAL USES Thermoplastic Pipe Reinforced Thermosetting Resin Pipe Resins Used for Piping Desirable Qualities of FRP Resins PROPERTIES Physical and Mechanical Flow Properties Chemical Resistance... 

EIDPE pipes reinforced with aramide tape can withstand 7.0 MPa operating pressures for service lives of 50 years. Multilayer pipes are made of a standard PE inner layer wrapped with aramide tape. 

LORUS is also used for inspection of piping that has been on supports or sleepers for some time, to see whether corrosion has developed at the contact points. But the technique can also be used for corrosion detection under insulation, inspection of pipelines at dike and road crossings, nozzle reinforcement pads or craek detection in suspension systems for railway cars. 

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. 

Reinforced furan resias have been used for many years in process piping and in underground sewer or waste-disposal systems. With a wide range in pH acceptability and good solvent resistance, furan piping has been a logical choice for many services. 

Concrete Products. Limestone aggregate is used competitively with other aggregate in the manufacture of molded, reinforced, and prestressed concrete products in the form of block, brick, pipe, panels, beams, etc. 

Fiberglass Reinforced Piping Systems for Chemical andindustrialApplications, Smith Eiberglass Products, Inc., Litde Rock, Ark., 1993 to 1994. 

There are many different equipment options avaQable to suit specific product needs including continuous winders for pipe, multiaxis winders for pressure vessels, and simple lathe-type winders for tanks and large pipe. Specialty machines combine a chopped reinforcement with continuous fibers for tank walls and large-diameter pipe where both stiffness and tensQe strength are required. Textile braiders have also been adapted for use as continuous... 

Centrifugal casting is used to produce water softener tanks and pipe by saturating a reinforcement with thermosetting resin within a mold that is then rotated at high speed to consoHdate the laminate before curing. 

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. 

The avadabihty of PMDI also led to the development of polyurethane-modified isocyanurate (PUIR) foams by 1967. The PUIR foams have superior thermal stabiUty and combustibiUty characteristics, which extend the use temperature of insulation foams well above 150°C. The PUIR foams are used in pipe, vessel, and solar panel insulation glass-fiber-reinforced PUIR roofing panels having superior dimensional stabiUty have also been developed. More recently, inexpensive polyester polyols based on residues obtained in the production of dimethyl terephthalate (DMT) have been used in the formulation of rigid polyurethane and PUIR foams. 

The reinforcing properties of asbestos fibers have been widely exploited in asbestos—cement products mosdy for the constmction industry and sanitation (sheets, pipes). Into the 1990s, asbestos—cement products represent by fat (f 70%) the largest industrial consumption of asbestos fibers. 

Type I (Normal). This is the general purpose Pordand cement used for all appHcations where special properties are not needed. Common appHcations include concretes for paving, building doors, roof decks, reinforced concrete buildings, pipes, tanks, bridges, and other precast concrete products. In 1989 Type I and Type II accounted for over 92% of the Pordand cement produced in U.S. plants. Exact data are not available that separate Type I and Type II Pordand cement, but it can be assumed that Type I production was much greater than Type II. 

Polypropylene can be fabricated by almost any process used for plastics (see Plastics processing). The extmsion of pipe and injection mol ding of fittings present no unusual problem. However, there is no way to bond the fittings to the pipe except by remelting the polymer, which is impractical on most constmction sites. The resin can be reinforced by glass fibers, mineral fillers, or other types of fillers and can be pigmented readily. 

Fig. 4. Top view of Soderberg electrode showiag reinforcing fins and steel casiag with hoUow electrode pipe at the center.

Recommended materials of constmction for pipes, tanks, and pumps handling citric acid solutions are 316 stainless steel, fiber glass-reinforced-polyester, polyethylene, polypropylene, and poly(vinyl chloride). At elevated temperatures, 304 stainless steel is not recommended (Table 8). 

---