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60-540: The German Krah GmbH does production and installation of pipe production plants for plastic pipe in diameters up to 4000 mm. Currently, it is headquartered in Schutzbach , Germany . The family-owned company has a 40-year history rooted in a small engineering company specializing in the design of small machines and tools, founded by Karl-Heinz Krah in 1968 in Westerwald . Over time, the company has developed from

120-576: A 50% share in the company. The remaining shares are held equally by Karl-Heinz Krah and Alexander Krah. In 2008 the Krah pipe manufacturer (Krah Pipe Systems) in Greenwood/USA set up the world's first plant for large diameter helical extrusion pipes, ranging up to 120 inches (3,048 mm) for municipal water. This German corporation or company article is a stub . You can help Misplaced Pages by expanding it . Plastic pipe Plastic pipe

180-404: A flexible metallic layer as the middle of three bonded layers. Barrier pipe is used, for example, to provide additional protection for the contents passing through the pipe (particularly drinking water) from aggressive chemicals or other pollution when laid in ground contaminated by previous use. Most plastic pipe systems are made from thermoplastic materials. The production method involves melting

240-473: A good choice for in-house warm water supply. Polyvinylidene difluoride (PVDF) is a fairly non-reactive, thermoplastic fluoropolymer with excellent chemical and thermal resistance for plastic pipework uses. PVDF resin is produced through polymerization of the vinylidene fluoride monomer. The PVDF resin is then used to make PVDF pipe as well as many other products. Industries and applications select PVDF pipe due to its inert, durable qualities. PVDF piping

300-434: A homogeneous matrix of thermoplastic material which is ready for use in a pipeline. Structured-wall pipes and fittings are products which have an optimized design with regard to material usage to achieve the physical, mechanical and performance requirements. Structured Wall Pipes are tailor made solutions of piping systems, for a variety of applications and in most cases developed in cooperation with users. Pipe incorporating

360-522: A large proportion of plastic piping installations and some estimations put it that greater than 2,000,000 miles (3,200,000 km) of uPVC pipe are currently in service across applications. Based on the standard polyvinyl chloride material, three other variants are in use. One variant called OPVC, or PVCO, represents an important landmark in the history of plastic pipe technology. This molecular-oriented bi-axial high performance version combines higher strength with extra impact resistance. A ductile variant

420-463: A popular engineering plastic. It can be tailored to a range of applications by modifying the ratio of the individual chemical components. They are used mainly in industrial applications where high impact strength and rigidity are essential. This material is also used in non-pressure piping systems for soil and waste. Chlorinated polyvinyl chloride (CPVC) is resistant to many acids, bases, salts, paraffinic hydrocarbons, halogens and alcohols. It

480-404: A product surface. PVDF is widely used in the chemical industry as piping for aggressive chemicals and high purity liquids. The PVDF material is used in construction, transportation, chemical processes, electricity, batteries, waste water and treatment. Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene is commonly recognized under the brand name Teflon . PTFE

540-513: A small workshop and "one man show" to a worldwide manufacturer of specialized machines in pipe production plants for big diameters of non pressure plastic pipes, as well as plastic pressure pipes . The company is still family-managed, currently by Alexander Krah, the youngest son of Karl-Heinz Krah. The company has production facilities in Spain, Croatia, Germany, Argentina, USA, Kuwait, Oman and Mexico. In 2007 an Arab investor injected money in cash for

600-598: A unique resin identification code. Items made from polycarbonate can contain the precursor monomer bisphenol A (BPA). Susceptible to UV light, exposure results in yellowing (degradation is especially visible in headlamps that lost or didn't have proper protective coating). Polyether sulfone (PES) or polysulfone is a class of specially engineered thermoplastics with high thermal, oxidative, and hydrolytic stability, and good resistance to aqueous mineral acids, alkalis, salt solutions, oils and greases. Polyoxymethylene (POM), also known as acetal, polyacetal and polyformaldehyde,

660-584: A useful life span of over 100 years. Plastic pipes have been used in service for over 50 years. The predicted lifetime of plastic piping systems exceeds 100 years. Several industry studies have demonstrated this prognosis. Plastic pipe materials have always been classified on the basis of long-term pressure testing. The measured failure times as a function of the stresses in the pipe wall has been demonstrated in so-called Regression Curves. An extrapolation based on measured failure times has been calculated to reach 50 years. The predicted failure stress at 50 years

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720-431: Is Nominal Stiffness (kN/m2). Stiffness of pipes is important if they are to withstand external loadings during installation. The higher the figure, the stiffer the pipe. After correct installation, pipe deflection remains limited but it will continue to some extent for a while. In relation to the soil in which it is embedded, the plastic pipe behaves in a 'flexible' way. This means that further deflection in time depends on

780-421: Is a family of similar materials categorized according to their density and molecular structure. It is also known as poly and is obtained by the addition polymerisation of ethylene. It may be of low density or high density depending upon the process used in its manufacturing. It is resistant to moisture and most of the chemicals. It is flexible at room temperature (and low temperature) and can be heat sealed. Since it

840-1009: Is a synthetic fiber with a very high melting point. It has exceptional thermal and chemical stability and does not readily ignite. It was first discovered by American polymer chemist Carl Shipp Marvel in the pursuit of new materials with superior stability, retention of stiffness, toughness at elevated temperature. Due to its high stability, polybenzimidazole is used to fabricate high-performance protective apparel such as firefighter's gear, astronaut space suits, high temperature protective gloves, welders' apparel and aircraft wall fabrics. In recent years, polybenzimidazole found its application as membrane in fuel cells. Polycarbonate (PC) thermoplastics are known under trademarks such as Lexan, Makrolon, Makroclear, and arcoPlus. They are easily worked, molded, and thermoformed for many applications, such as electronic components, construction materials, data storage devices, automotive and aircraft parts, check sockets in prosthetics, and security glazing. Polycarbonates do not have

900-524: Is a thermoplastic material derived from common salt and fossil fuels. The pipe material has the longest track record of all plastic materials. The first uPVC pipes were made in the 1930s. Beginning in the 1950s, uPVC pipes were used to replace corroded metal pipes and thus bring fresh drinking water to a growing rural and later urban population. uPVC pipes are certified safe for drinking water per NSF Standard 61 and used extensively for water distribution and transmission pipelines throughout North America and around

960-428: Is a tough, lightweight material that is durable, fairly rigid and versatile, and is resistant to acids and bases. Much of it is used by the construction industry, such as for vinyl siding, drainpipes, gutters and roofing sheets. It is also converted to flexible forms with the addition of plasticizers, thereby making it useful for items such as hoses, tubing, electrical insulation, coats, jackets and upholstery. Flexible PVC

1020-742: Is a tubular section, or hollow cylinder, made of plastic . It is usually, but not necessarily, of circular cross-section, used mainly to convey substances which can flow—liquids and gases (fluids), slurries, powders and masses of small solids. It can also be used for structural applications; hollow pipes are far stiffer per unit weight than solid members. Plastic pipework is used for the conveyance of drinking water , waste water , chemicals , heating fluid and cooling fluids , foodstuffs , ultra-pure liquids, slurries , gases , compressed air , irrigation , plastic pressure pipe systems , and vacuum system applications . There are three basic types of plastic pipes: Extruded pipes consisting of one layer of

1080-421: Is also used in inflatable products, such as water beds and pool toys. PVC is also a common material in vinyl action figures , especially in countries such as Japan , where the material is used extensively in so-called Sofubi figures (Soft vinyl toys ). As PVC bends easily and has a tendency to be bent during transit, a method to mitigate this deformation is to heat the plastic until it becomes mobile, then reform

1140-422: Is an engineering thermoplastic used in precision parts requiring high stiffness, low friction, and excellent dimensional stability. As with many other synthetic polymers, it is produced by different chemical firms with slightly different formulas and sold variously by such names as Delrin, Celcon, Ramtal, Duracon, Kepital and Hostaform. Polyether ether ketone (PEEK) is a colourless organic thermoplastic polymer in

1200-420: Is an inexpensive plastic it is made in large amounts to cater to the demand. For example: Polyphenylene oxide (PPO), which is obtained from the free-radical, step-growth oxidative coupling polymerization of 2,6-xylenol, has many attractive properties such as high heat distortion and impact strength, chemical stability to mineral and organic acids, and low water absorption. PPO is difficult to process, and hence

1260-653: Is any plastic polymer material that becomes pliable or moldable at a certain elevated temperature and solidifies upon cooling. Most thermoplastics have a high molecular weight . The polymer chains associate by intermolecular forces , which weaken rapidly with increased temperature, yielding a viscous liquid. In this state, thermoplastics may be reshaped, and are typically used to produce parts by various polymer processing techniques such as injection molding , compression molding , calendering , and extrusion . Thermoplastics differ from thermosetting polymers (or "thermosets"), which form irreversible chemical bonds during

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1320-519: Is commonly used in water, chemical, hot and cold, delivery systems for residential, commercial, and industrial applications. Poly vinylidene fluoride , PVDF , belongs to the fluoropolymer class of thermoplastics and is known for its high chemical inertness and resistance. PVDF is obtained through the polymerization of the vinylidene fluoride monomer. PVDF thermoplastic is fabricated into sheets and pipes for engineering uses as well as powders and coatings that can be dissolved in solvents and applied across

1380-493: Is defined by the recyclable plastic number 5. Although relatively inert, it is vulnerable to ultraviolet radiation and can degrade considerably in direct sunlight. Polypropylene is not as impact-resistant as the polyethylenes (HDPE, LDPE). It is also somewhat permeable to highly volatile gases and liquids. Polystyrene is manufactured in various forms that have different applications and can have medium to very low density. Extruded polystyrene (PS or xPS, sometimes colored pink/blue)

1440-661: Is extensively used to make signs, including lettering and logos. In medicine, it is used in bone cement and to replace eye lenses. Acrylic paint consists of PMMA particles suspended in water. For many decades, PMMA has been the predominant methacrylic ester produced worldwide. Major players in the PMMA market are Mitsubishi Rayon (Japan), Arkema SA (France), LG MMA (South Korea), Chi Mei Corp. (Taiwan), Sumimoto Chemical Company Ltd (Japan), Evonik Industries (Germany), BASF (Germany), Dow Chemical Company (U.S.), AkzoNobel (The Netherlands), Quinn Plastics (UK) and Cytec Industries (U.S.). Regarding

1500-439: Is necessary, as light is scattered strongly by crystallites larger than its wavelength. Amorphous and semi-amorphous plastics are less resistant to chemical attack and environmental stress cracking because they lack a crystalline structure. Brittleness can be decreased with the addition of plasticizers , which increases the mobility of amorphous chain segments to effectively lower the glass transition temperature. Modification of

1560-433: Is not resistant to solvents, aromatics and some chlorinated hydrocarbons. It can carry higher temperature liquids than uPVC with a max operating temperature reaching 200 °F (93.3 °C). Due to its greater temperature threshold and chemical resistance, CPVC is one of the main recommended material choices in residential, commercial, and industrial water and liquid transport. High-density polyethylene (HDPE) - HDPE pipe

1620-401: Is often referred to as unplasticized polyvinyl chloride (uPVC), which is the more commonly used type for installations such as water, waste, and sewer conveyance plumbing. Chemical modification often produces more drastic changes in properties. Chlorinated polyvinyl chloride (CPVC) is produced through exposing PVC to the continued free-radical chlorination reaction that originally formulates

1680-503: Is principally used in coating applications. This is done by spraying an aqueous slurry of PPS particles and heating to temperatures above 370 °C. Particular grades of PPS can be used in injection and compression molding at temperatures (300 to 370 °C) at which PPS particles soften and undergo apparent crosslinking. Principal applications of injection and compression molded PPS include cookware, bearings, and pump parts for service in various corrosive environments. Polypropylene (PP)

1740-429: Is small but steadily growing. In some markets, e.g. Kuwait, UK, Korea and Spain, PB-1 has a strong position. Polyethylene has been successfully used for the safe conveyance of potable and waste water, hazardous waste, and compressed gases for many years. Two variants are HDPE pipe ( high-density polyethylene ) and the more heat resistant PEX (cross-linked polyethylene, also XLPE). PE has been used for pipes since

1800-735: Is strong, flexible and light weight. It has a zero leak rate when fused together. PB-1 is used in pressure piping systems for hot and cold potable water, pre-insulated district heating networks, and surface heating and cooling systems. Key properties are weldability, temperature resistance, flexibility and high hydrostatic pressure resistance. One standard type, PB 125, has a minimum required strength (MRS) of 12.5 MPa. It also has low noise transmission, low linear thermal expansion, no corrosion and calcification. PB-1 piping systems are no longer sold in North America. Market share in Europe and Asia

1860-617: Is the MPVC, polyvinyl chloride modified with acrylics or chlorinated PE. This more ductile material with high fracture resistance is used in higher-demand applications where resistance against cracking and stress corrosion is important. In several studies the long track record of uPVC pipes has been investigated. Recent investigations at the German KRV and the Dutch TNO have confirmed that uPVC water pressure pipes, when installed correctly have

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1920-409: Is used for the conveyance of potable water, slurries and chemicals. Most commonly used for DWV (drain-waste-vent) applications. It has a wide temperature range, from -40 °C to +60 °C. ABS is a thermoplastic material and was originally developed in the early 1950s for use in oil fields and the chemical industry. The variability of the material and its relative cost effectiveness has made it

1980-481: Is used in many consumer products, such as toys, appliances, and telephones. Nylon belongs to a class of polymers called polyamides . It has served as a substitute mainly for hemp, cotton and silk, in products such as parachutes, cords, sails, flak vests and clothing. Nylon fibres are useful in making fabrics, rope, carpets and musical strings, whereas, in bulk form, nylon is used for mechanical parts including machine screws, gears and power tool casings. In addition, it

2040-469: Is used in the manufacture of disposable cutlery, rigid ground contact rated insulating foam board, CD and DVD cases, plastic models of cars and boats, and smoke detector housings. Expanded polystyrene foam (EPS or "styrofoam", white) is used in making insulation and packaging materials, such as the "peanuts" and molded foam used to cushion fragile products. Polystyrene copolymers are used in the manufacture of toys and product casings. Polyvinyl chloride (PVC)

2100-698: Is used in the manufacture of heat-resistant composite materials. Polylactic acid (polylactide) is a compostable thermoplastic aliphatic polyester derived from renewable resources , such as corn starch (in the United States), sugar beet pulp (in Europe), tapioca roots, chips or starch (mostly in Asia), or sugarcane . It is the most common material used for 3D printing with fused deposition modeling (FDM) techniques. Polybenzimidazole (PBI, short for Poly-[2,2’-(m-phenylen)-5,5’-bisbenzimidazole]) fiber

2160-727: Is used most in the chemical process industry due to its ability to plumb aggressive, corrosive solutions. PVDF pipe also sees common use in high purity applications, semi-conductor fabrication, electronics / electricity, pharmaceutical developments, and nuclear waste processing. PVDF piping specifications and performance characteristics approve PVDF pipe up to 248 °F (120 °C) under pressurized system conditions. The pipe does not support fungus growth according to military test standard method 508, 81-0B. Dissimilar from other common thermoplastic pipes, (uPVC, CPVC, PE, PP), PVDF does not exhibit sensitivity to UV light or ozone oxidative damage, approving it for long term outdoor uses. uPVC or PVC-U,

2220-508: Is useful for such diverse products as reusable plastic food containers, microwave- and dishwasher-safe plastic containers , diaper lining, sanitary pad lining and casing, ropes, carpets, plastic moldings, piping systems, car batteries , insulation for electrical cables and filters for gases and liquids. In medicine, it is used in hernia treatment and to make heat-resistant medical equipment. Polypropylene sheets are used for stationery folders and packaging and clear storage bins. Polypropylene

2280-414: The polyacrylic acids (PAA) and its ester derivatives (PAc) market, on the other hand, the poly(methyl methacrylate) (PMMA) market. PMMA is also known by trade names such as Lucite, Perspex and Plexiglas. It serves as a sturdy substitute for glass for items such as aquariums, buttons, motorcycle helmet visors, aircraft windows, viewing ports of submersibles, and lenses of exterior lights of automobiles. It

2340-481: The PAA and PAc market, key manufacturers are Nippon Shokubai Company Ltd. (Japan), Arkema SA (France) and Dow Chemical Company (U.S.) Acrylonitrile butadiene styrene (ABS) is a terpolymer synthesized from styrene and acrylonitrile in the presence of polybutadiene . ABS is a light-weight material that exhibits high impact resistance and mechanical toughness. It poses few risks to human health under normal handling. It

2400-576: The PVC polymer. The chlorination reaction continues to add chlorine atoms to the polymer hydrocarbon backbone until most commercial applications reach a percent range between 56 and 74% total chlorine. This increase in elemental chlorine content contributes to CPVC's increased expression of chlorine-based characteristics, such as chemical durability, resistance to acids, bases, and salts; susceptibility to ammonia-based compounds, aromatics, esters, ketones; chemical stability; heat energy transfer resistance. CPVC

2460-465: The US for homes since 2006. Code IRC P2904.5 uPVC Not listed. uPVC has high chemical resistance across its operating temperature range, with a broad band of operating pressures. Max operating temperature is reported at 140 °F (60 °C), and max working pressure: 450 psi (3,100 kPa). Due to its long-term strength characteristics, high stiffness and cost effectiveness, uPVC systems account for

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2520-428: The commercial resin (Noryl) is made by blending PPO with high-impact polystyrene (HIPS), which serves to reduce the processing temperature. Polyphenylene sulfide (PPS) obtained by the condensation polymerization of p-dichlorobenzene and sodium sulfide, has outstanding chemical resistance, good electrical properties, excellent flame retardance, low coefficient of friction and high transparency to microwave radiation. PPS

2580-504: The curing process. Thermosets do not melt when heated, but typically decompose and do not reform upon cooling. Above its glass transition temperature and below its melting point , the physical properties of a thermoplastic change drastically without an associated phase change . Some thermoplastics do not fully crystallize below the glass transition temperature, retaining some or all of their amorphous characteristics. Amorphous and semi-amorphous plastics are used when high optical clarity

2640-425: The early 1950s. PE pipes are made by extrusion in a variety of sizes dimensions. PE is lightweight, flexible and easy to weld. Its smooth interior finish ensures good flow characteristics. Continuous development of the material has enhanced its performance, leading to rapidly increasing usage by major water and gas utility companies throughout the world. The pipes are also used in lining and trench-less technologies,

2700-478: The ground loadings, whatever the soil settlement. This means that when a rigid pipe is subject to excessive loading, it will reach the limit for stress values more quickly and break. It can therefore be concluded that the flexibility of plastic pipes offers an extra dimension of safety. Buried Pipes need flexibility. Pipes, fittings, valves , and accessories make up a plastic pressure pipe system. The range of pipe diameters for each pipe system does vary. However,

2760-406: The last few decades. Often supplied in coils, it is flexible and can therefore be led around structures without fittings. Its strength at temperatures ranging from below freezing up to almost boiling makes it an ideal pipe material for hot and cold water installations, radiator and under floor heating, de-icing and ceiling cooling applications Polyethylene of Raised Temperature (RT) or PE-RT expands

2820-412: The long track record with expected lifetime of more than 50 years. Cross-linked polyethylene is commonly referred to as XLPE or PEX. It is a thermoplastic material that can be made in three different ways depending how the cross-linking of the polymer chains is being made. PEX was developed in the 1950s. It has been used for pipes in Europe since the early 1970s and has been gaining rapid popularity over

2880-428: The material into the desired shape. PVC is produced in many specific modifications to affect its chemical and physical properties. In plasticized polyvinyl chloride (pPVC), plasticizers are added to the raw material before molding to make it more flexible or pliable. Early on, the health and environmental aspects of this were poorly understood and replacements and product bans resulted after studies. The original form

2940-495: The material, shaping and then cooling. Pipes are normally produced by extrusion . Plastic pipe systems fulfil a variety of service requirements. Product standards for plastics pipe systems are prepared within the CEN/TC155 standards committee. These requirements are described in a set of European Product Standards for each application alongside their specific characteristics, for example: Plastic pipes are capable of fulfilling

3000-621: The pharmaceutical and chemical industries. PP is a thermoplastic polymer made from polypropylene. It was first invented in the 1950s and has been used for pipes since the 1970s. Due to the high impact resistance combined with good stiffness and high chemical resistance makes this material suitable for sewer applications. A good performance at operating temperature range from up to 60 °C (140 °F) (continuous) makes this material suitable for in-house discharge systems for soil & waste. A special PP grade with high temperature behaviour up to 90 °C (194 °F) (short-term) makes that material

3060-544: The pipe will occur within the pipe wall. However, the induced stresses will never exceed the allowed limit values. The thermoplastic behavior of the pipe material is such that the induced stresses are relaxing to a low level. Induced strains are far below the allowable levels. This flexible behaviour means that the pipe will not fail. It will exhibit only more deflection while keeping its function without breaking. However, rigid pipes by their very nature are not flexible and will not follow ground movements. They will bear all

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3120-696: The polyaryletherketone (PAEK) family, used in engineering applications. It was originally introduced by Victrex PLC, then ICI (Imperial Chemical Industries) in the early 1980s. It has attractive properties like good abrasion resistance, low flammability and emission of smoke and toxic gases. Polyetherimide (PEI), produced by a novel nitro displacement reaction involving bisphenol A, 4, 4’-methylenedianiline and 3-nitrophthalic anhydride, has high heat distortion temperature, tensile strength and modulus. They are generally used in high performance electrical and electronic parts, microwave appliances, and under-the-hood automotive parts. Polyethylene (polyethene, polythene, PE)

3180-494: The polymer through copolymerization or through the addition of non-reactive side chains to monomers before polymerization can also lower it. Before these techniques were employed, plastic automobile parts would often crack when exposed to cold temperatures. These are linear or slightly branched long chain molecules capable of repeatedly softening on heating and hardening on cooling. Today's acrylics industry can be divided into two distinct multibillion-dollar markets: on one hand

3240-410: The settlement of the soil around the pipe. Basically, the pipe follows the soil movement or settlement of the backfill, as technicians call it. This means that good installation of pipes will result in good soil settlement. Further deflection will remain limited. For flexible pipes, the soil loading is distributed and supported by the surrounding soil. Stresses and strains caused by the deflection of

3300-1139: The size ranges from 12 to 400 mm (0.472 to 15.748 in) and 3 ⁄ 8 to 16 in (9.53 to 406.40 mm). Pipes are extruded and are generally available in: 3 m (9.84 ft), 4 m (13.12 ft), 5 m (16.40 ft), and 6 m (19.69 ft) straight lengths and 25 m (82.02 ft), 50 m (164.04 ft), 100 m (328.08 ft), and 200 m (656.17 ft) coils for LDPE and HDPE. Pipe fittings are moulded and come in many sizes: tee 90° equal (straight and reducing), tee 45°, cross equal, elbow 90° (straight and reducing), elbow 45°, short radius bend 90° socket/coupler (straight and reducing), union, end caps, reducing bush, and stub, full face, and blanking flanges. Valves are moulded and also come in many types: ball valves (also multiport valve), butterfly valves , spring-, ball-, and swing-check non-return valves, diaphragm valves , knife gate valve, globe valves and pressure relief/reduction valves. Accessories are solvents, cleaners, glues, clips, backing rings, and gaskets. Thermoplastic A thermoplastic , or thermosoftening plastic ,

3360-444: The so-called no-dig applications where the pipes are installed without digging trenches without any disruption above ground. Here the pipes may be used to line old pipe systems to reduce leakage and improve water quality. These solutions are therefore helping engineers to rehabilitate antiquated pipe systems. Excavation is minimal and the process is carried out quickly below ground. Also for PE pipe material, several studies demonstrated

3420-429: The specific requirement for each application. They do so over a long lifetime and with reliability and safety. The key success factor is achieved by maintaining consistently high quality levels. For plastic pipe products, these levels are defined by the different standards. Two aspects are fundamentally important for the performance of plastic pipes: flexibility and long lifetime. Acrylonitrile butadiene styrene (ABS)

3480-399: The traditional properties of polyethylene. Enhanced strength at high temperatures are thus made possible through special molecular design and manufacturing process control. Its resistance to low or high temperatures makes PE-RT ideal for a broad range of hot and cold water pipe applications. Polypropylene is suitable for use with foodstuffs, potable and ultra pure waters, as well as within

3540-523: The world. uPVC is allowed for waste lines in homes and is the most often used pipe for sanitary sewers. Further pressure and non-pressure applications in the field of sewers, soil and waste, gas (low pressure) and cable protection soon followed. The material's contribution to public health, hygiene and well-being has therefore been significant. Polyvinyl chloride or uPVC (unplasticized polyvinyl chloride) pipes are not well suited for hot water lines and have been restricted from inside water supply line use in

3600-535: Was taken as a basis for the classification. This value is called MRS, Minimum Required Stress, at 50 years. Some reasons why plastic piping systems may fail are poor product bonding/gluing during installation and naturally-occurring physical damage, such as from tree root infiltration. Plastic pipes were also found to fail more often during dry, hot summers. Plastic Pipes are classified by their ring stiffness . The preferred stiffness classes as described in several product standards are: SN2, SN4, SN8 and SN16, where SN

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