Thermoplastic plastic piping applications

ISO 4433-4 1997 Thermoplastics pipes - Resistance to liquid chemicals - Classification -Part 4 Poly(vinylidene fluoride) (PVDF) pipes ISO 9393-2 1997 Thermoplastics valves - Pressure test methods and requirements - Part 2 Test conditions and basic requirements for PE, PP, PVC-U and PVDF valves ISO 10931-1 1997 Plastics piping systems for industrial applications - Poly(vinylidene fluoride) (PVDF) - Part 1 General... 

Thermoplastic Foam Extrusion. Foamed plastics find applications as rigid profiles, pipe, sheet, packaging material, and thermal insulation. Polystyrene (PS) finds the widest application in foamed products while poly(vinyl chloride) PVC, low-density polyethylene (LDPE), and acrylonitrile-butadiene-styrene (ABS) (21) are also used in large quantities. All common thermoplastics can be foamed by various techniques as described hereafter. 

Plastics are divided into two basic groups, thermosetting and thermoplastic, both of which are used in the manufacture of plastic pipe. Thermoplastics, as the name implies, soften upon the application of heat and reharden upon cooling they can be formed and reformed repeatedly. This characteristic permits them to be easily extruded or molded into a wide variety of useful shapes, including pipe and fittings. Because thermoplastics are shaped, by a die or mold, while in a molten state their properties are essentially isotropic (i.e., independent of direction). In some processes and under some conditions, some anisotropy (i.e., direction dependence) may result. 

Threading is also used with plastic pipe. However, molded threads are preferred for thermoplastics and are required for most thermosetting pipe. Molded threaded adapters are available and may be applied by solvent-cementing or with adhesive, whichever is applicable. Threads may not be cut on most thermosetting pipe for they may damage the structural integrity of the pipe wall. Thermoplastic pipe may be threaded, provided its wall thickness is not less than a prescribed minimum, normally at least that of Schedule 80 pipe. 

Thermoplastics Pipe (Plumbing Applications) Plastics Pipe Fittings Association, 999 North Main Street, Glen EUyn, IL 60137... 

Sixsmith, T. and R. Hanselka. 1997. Handbook of Thermoplastic Piping System Design. New York Marcel Dekker. This work covers in detail the advances in plastic pipe and piping systems and applications where modern plastics can be used in place of more traditional metal pipe. Includes over 70 pages of basic reference data and nearly 200 pages of chemical resistance data. 

Plastic pipes and fittings have been successfully used for a wide variety of piping applications for more than 60 years. There are several commonly used thermoplastic materials depending on the particular piping and/or fittings applications ... 

Thermoplastic piping is the material that has the widest range of applications. Thermoplastic piping includes many materials that have significant differences in characteristics and uses. It is important that the correct thermoplastic material be specified for the various applications. Because of the frequent use of polyethylene (PE) and polyvinyl chloride (PVC) pipe material in the water and gas markets, this handbook will focus primarily on these types of plastic pipe. Other types of plastic pipe and their applications will be introduced to provide the reader with a background in the various possible uses of the material. The design and installation information, however, will deal primarily with PE and PVC pipe. 

Thermoplastics make up the majority of plastic pipe in use today. PVC accounts for the majority of the thermoplastic pipe in nse, with PE coming in second. Although thousands of miles of plastic pipe are in service in natural gas and municipal applications, many other uses also exist. Some of the other conunon uses of plastic piping are ... 

Codes establish the minimum requirements for design, fabrication, materials, installation, inspection, and testing for most piping systems. Thermoplastics used for plumbing, sewer, water, gas distribution, and hazardous waste may come under the jurisdiction of a code or regulation. Some of the most frequently used codes for plastic piping products used for water and gas applications are ... 

Thermoplastic piping products are cost-effective solutions to a variety of piping applications and offer many advantages when compared to traditional metal piping materials. Some of these features, which have spurred the widespread acceptance of plastic piping materials for many applications, are ... 

Flexibility and toughness Most thermoplastic piping materials are flexible, which is an important characteristic for underground applications. The pipe can follow natural contours and transitions around obstacles, which reduces the number of fittings required in most piping applications. Because of their excellent flexibility characteristics, plastic piping materials woik well in harsh climate conditions. 

Thermoplastics are the primary plastic piping material in use today. They account for the largest percentage of plastic pipe in use and have the widest range of applications. Polyvinyl chloride (PVC) makes up the majority of the thermoplastic piping market polyethylene is the second most popular. 

The physical and mechanical properties of the principal thermoplastics of interest for process plant applications are listed in Table 3.42. Table 3.43 gives typical hydrostatic design stresses for different types of thermoplastic pipe. Plastics widely employed in piping systems are described briefly below. 

ISO 23711 2003 Elastomeric seals - Requirements for materials for pipe joint seals used in water and drainage applications - Thermoplastic elastomers ISO 14910-1 1997 Plastics - Thermoplastic polyester/ester and polyether/ester elastomers for moulding and extrusion - Part 1 Designation system and basis for specifications ISO 14910-2 1997 Plastics - Thermoplastic polyester/ester and polyether/ester elastomers for moulding and extrusion - Part 2 Preparation of test specimens and determination of properties... 

For insulation applications, plastics are mostly used. For water insulation (waterproofing), PU, PVC, thermoplastic elastomers, silicones, various rubbers, acrylics, and even PE are mainly used. For heat insulation applications, PVC, EPS, PU foams are used directly (for roofs and walls), as well as in sandwich panels. In addition, UPVC-hollow panels are being used as interior cladding to provide multi-purpose insulation (for water, heat, noise), specifically for pipes, wall insulation, and so on. 

Plastics are also now used as a replacement for concrete in underground chambers. The performance of chambers is much less critical than that of pipes since they are not under pressure and can be readily replaced when necessary. Increasingly, recycled polyolefins are being used in this kind of application, which is a particularly appropriate second use for mixed thermoplastic polymers that are not exposed to UV light (Chapter 4, page 86). 

All TP or TS matrix property can be improved or changed to meet varying requirements by using reinforcements. Typical thermoplastics used include TP polyesters, polyethylenes (PEs), nylons (polyamides/ PAs), polycarbonates (PCs), TP polyurethanes (PURs), acrylics (PMMAs), acetals (polyoxymethylenes/POMs), polypropylenes (PPs), acrylonitrile butadienes (ABSs), and fluorinated ethylene propylenes (FEPs). The thermoset plastics include TS polyesters (unsaturated polyesters), epoxies (EPs), TS polyurethanes (PURs), diallyl phthalates (DAPs), phenolics (phenol formaldehydes/PFs), silicones (Sis), and melamine formaldehydes (MFs). RTSs predominate for the high performance applications with RTFs fabricating more products. The RTPs continue to expand in the electronic, automotive, aircraft, underground pipe, appliance, camera, and many other products. 

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