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www.watersandfarr.co.nz 0800 923 7473

Issue: March 2017

Waters & Farr

TECHNICALPRODUCT CATALOGUE

PO Box 13329OnehungaAuckland, New ZealandP 0800 923 7473F +64 9 622 4037www.watersandfarr.co.nz

Information or advice contained in this catalogue or obtained from Waters & Farr otherwise is given in good faith. Waters & Farr make no warranty or representation regarding the information, opinions and recommendations contained in this catalogue. Users of this catalogue are advised to seek and rely upon their own professional advice and assessment of the matters contained in this catalogue. Waters & Farr excludes all liability to any user of this catalogue for consequential or indirect damages, or any other form of compensation or relief whatsoever for any acts or omissions of Waters & Farr, arising out of or in connection with the use of this catalogue irrespective of whether the same arises at law, inequity or otherwise.

ABOUT WATERS & FARR

Established in 1954, Waters & Farr is a leading manufacturer of polyethylene and polypropylene pipes for infrastructure and rural application. Overview

Manufacturing plants in Whanganui and Rangiora supported by distribution centres in Auckland, Whanganui and Christchurch supply our merchant and utilities customers with product throughout New Zealand. Over three hundred merchant stockists ensure stock is readily available for contractors, farmers and other end users.

Waters & Farr is always looking to the future. Plant upgrades have seen modern extrusion lines installed with higher outputs, jacket and stripe capability, and a range extension to 1200 mm diameter.

Commitment to quality

� Waters & Farr maintain quality management system certification to ISO9001 standard.

� ‘S’ mark certification to AS/NZS 4130 and AS/NZS 5065 is maintained with a third party.

� Pipe Test NZ, a division of Waters & Farr, was established as an independent testing laboratory. It is accredited by IANZ to conduct tensile, pressure, reversion and joint testing for Waters & Farr, and third party pipe, electrofusion and butt weld testing.

� Waters & Farr follow founding policies that underpin commitment and performance outcomes to achieve our vision & values.

How To Find Us Waters & Farr Terms and Conditions

POLyEThyLENE (PE) W

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POLYETHYLENE (PE)Polyethylene (PE) and Polypropylene (PP) are hydrocarbon based semi crystalline polymers often engineered for a specific application or purpose. Selection of raw stock, catalyst and process for synthesis combined with further compounding with additives is aimed to improve properties such as resistance to internal pressure and external loading, to crack propagation and impact, to oxidation and UV, mechanical strength and flexibility.

PE and PP polymers in their raw form are of translucent off-white colour. Pipe compounds are supplied in pellet form as a final raw material of a specific colour for processing in products or in natural colour for mixing with required additives during extrusion. Fig. 1 shows a typical example of PE compound granules used in pipe production, with the carbon black being distributed throughout the material to enhance UV resistance.

STRUCTURAL CONSIDERATIONSSemi-crystalline structure of PE and PP means that the polymer, when cooled, contains both tighter packed “crystalline” regions and loosely packed “amorphous” areas (Fig. 2 Beaded Carbon Black Pigmented Plastic Prior to Extrusion). Amorphous regions formed between the crystals are mostly made up from so-called “tie molecules” (schematically shown on Fig. 4 Tie molecules), usually partly embedded in the crystalline and partly in the amorphous zones. When external forces are applied, they will therefore play a big role in holding the crystalline areas together.

Side branches of macromolecules may disrupt formation of crystals; resulting “packing” of long-chain molecules (“macromolecules”) plays major part in final density of the polymer. Polyethylene formed by different processes may be separated in 3 main types of raw polymer:

high Density Polyethylene (hDPE), usual density range between 943 kg/m³ and 954 kg/m³, Medium Density Polyethylene (MDPE), usual density range between 932 kg/m³ and 942 kg/m³, Low Density Polyethylene (LDPE), usual density range up to 931 kg/m³.

Density of polypropylene is usually in the range between 900 kg/m³ and 910 kg/m³.

The size of polymer molecule is represented by its molecular mass (often called “molecular weight”) – the total of the atomic weight of all the atoms in the molecule. Molecular weight is controlled during the polymerisation by type and conditions of process and catalyst used; length of forming molecular chains varies from the predominant length. Resulting molecular weight is usually expressed in form of Molecular Mass Distribution (MMD), often called “Molecular Weight Distribution (MWD)”, which shows the frequency of occurring of molecules of certain lengths within the polymer.

While earlier PE pipe grades represented one predominant molecular length range (“Unimodal MWD” on Fig. 4 Tie molecules), by modifying polymerisation process, or by combining two different types of processes, manufacturers have developed polyethylene which seems to represent a combination of two polymer populations of particular molecular weight range - such MWD is called “Bimodal”.

Fig. 1 Molecular Weight Distribution

Fig. 2 Beaded Carbon Black Pigmented Plastic Prior to Extrusion

Fig. 3 Semi-crystalline polymer

Fig. 4 Tie molecules

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Fig. 5 Figure 5.0 Regression curves for PE100 and PE80

CLASSIFICATION OF PE PRESSURE COMPOUNDSIn designing a pressure pipe system, resistance to cracking under internal pressure and long term durability are two of the major considerations. Polyethylene compounds are classified by Minimum Required Strength (MRS) - hydrostatic strength at 20°C in 50 years time predicted using regression curves constructed based on testing multiple samples at controlled temperatures and pressures.

Polyethylene pressure pipe grades are then classified as (regression curve examples shown on Figure 5.0):PE80B, or PE80, MRS of 8.0 MPa, PE100, MRS of 10.0 MPa.

Another key element in PE pressure pipe material performance its resistance to cracking. Rapid crack propagation resistance is essential in classifying a grade as PE100 (minimum critical pressure determined by testing to be 1.0 MPa). Slow crack growth resistance is determined by notching pipe samples before subjecting them to internal pressure - pipes need to survive 500 h of testing without failure.

CLASSIFICATION OF PP MATERIALSPolypropylene compounds are mainly based on three types of polymer:

� homopolymer (PP-h) incorporating just propylene elemental units; used for both pressure and drainage applications but requires higher safety factor resulting in thicker pipe walls,

� Random copolymer (PP-R) incorporating randomly placed ethylene elemental units; used widely for hot water supply, � Block copolymer (PP-B) incorporating blocks of propylene elemental units separated by occasional ethylene ones; used widely for gravity drainage/sewers thanks to high resistance to external loading in pipes.

LOAD RESISTANCE AT ELEVATED TEMPERATURESResistance of materials in pipe form to internal pressure and external loading reduces when temperature is higher than 20°C. This results in lower allowable pipeline operating pressure, or incorporation of higher stiffness rated pipe in design where pipe wall temperature is elevated.

PRODUCT RANGE W

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PRODUCT RANGE

POTABLE WATER AND IRRIGATION PIPE

SEWERAGE, STORM WATER AND GRAVITY DRAINAGE PIPE

PRESSURE PIPE, DUCTING AND CONDUIT

quality standards

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QUALITY STANDARDS

TABlE 1 Table 1.0 W&F Product Range (length and rating are size dependent)

Product Applications Sizes Rating delivery Units Options Standards

Pressure PE100

Potable watergas, compressed airIrrigationSewerage, drainageIndustrial, ruralVacuumhDD, TrenchlessinstallationRehabilitation

16-1200mm Water:Up to 25 bar

Lengths 6-18m StripedJacketed Solid Colour

AS/NZS 4130

Pressure PE80, MdPE

Potable waterGas Rural EffluentIrrigation

Water:Up to 20 bar

Coils 25 -200mLengths 6-18m

Marking linesJacketedSolid Color

AS/NZS 4130

CivilBossPP

Municipal Road (NZTA approved) CulvertsWastewaterStorm water

225-450mm ID SN16 6 m Length Marking LineGrey Inner Layer / Black outer layer

AS/NZS 5065

Vision Pipe Storm waterWastewater

110-180mm NA 6-12 m Terracotta bore/ black jacket

AS/NZS 5065

FarmBoss Rural CulvertsDrainage

225-450mm ID SN6 6 m Length Marking Line AS/NZS 5065 dimensions only

ldPE Rural Irrigation Gun Tube Domestic irrigation

13-50mm ID 3-10 bar Coils 25-300m Pressure pipe Laterals

Orange electrical ducting

Electrical cabling 20-180mm NA Coils 50 -1000mLengths 6-12m

Orange JacketSolid color

AS/NZS 4130 dimensions only

green tele-communication ducting

Copper and fiber optics cabling

20-110mm NA Coils 50 -1000mLengths 6-12m

Green JacketSolid color

AS/NZS 4130 dimensions only

COMPLIANCE TO MANUFACTURING STANDARDSConfirmed by internal testing and third party assessment: Pressure and drainage pipes to AS/NZS 4130 / AS/NZS 5065 - Bureau Veritas S-Mark Licences Nos. 2722, 2729 & 2730, Quality Management system to AS/NZS 9001 - Telarc.

TESTING SERVICES Pipe Test NZ, a division of Waters & Farr Ltd, is an IANZ accredited laboratory. Pipe Test NZ provides independent external testing of PE/PP pipes, fusion welds and joints, as well as all Waters & Farr internal type and batch testing , assuring a complete quality package around the product and installers.

DESIGN NOTES W

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DESIGN NOTESIn considering polyethylene or propylene pipes, it has to be acknowledged that the pipes hydraulically smooth ensuring efficient flow of fluids, and are flexible transferring a part of external loadings into surrounding soil. The materials are visco-elastic, which means it can be placed under short term stress, for example tensile/radial loading or pressure surge, and then elastically return to its previous state or shape when the short term loading has dropped or is removed. This means PE and PP pipes can accommodate operating and installation conditions, such as water hammer, trenchless installation, short term construction equipment loads, without the material being negatively influenced when correctly designed and installed.

PIPE DEFINITIONS PN, SDR, SN, MAOPSDR: Standard Dimension Ratio, a nominal ratio of outside diameter, Dm, and wall thickness, T, may be expressed as SDR = Dm/Tmin. Together with the material type, SDR defines the pressure rating of a plain wall pipe.

PN: Pressure Nominal, a nominal working internal pressure for a water conveying pipe expressed in bar ( 1 bar =100 kPa = 0.1 MPa, or approximately 14.5 psi ). PN is normally referenced in MPa, so for example a water pipe labeled ‘PN 8’ is intended for nominal working pressure at 20°C not exceeding 0.8 MPa, or 8.0 bar.

SN: Stiffness Nominal, typically used in identification of pipes intended for non-pressurized systems. Ring-bending stiffness of both pressure and non-pressure pipes is required for structural design of flexible pipes. Stiffness is calculated or determined by experimentation, especially for structured wall pipes. SN is expressed in kN/m/m, so for example a pipe labelled ‘SN 16’ is of stiffness at 20°C of not less than 16 kN/m/m, or 16000 N/m/m.

MAOP: Maximum Allowable Operating Pressure, is the maximum pressure that can be sustained by a pressure pipe for its estimated useful life under the anticipated operating conditions. Design factor, C, selected based on anticipated conveyed fluid, pipe form, installation method, wall temperature, pipeline location, together with the type and class of pipe define MAOP, which is normally expressed in MPa. MAOP does not take into account short term effectslike water hammer which for PE pipe may be typically allowed up to 1.5 times operating pressure. For Series 1 pipes to AS/NZS 4130 (minimum value of C being 1.25):

MAOP = 0.125PN C

PIPE DIMENSION RELATIONSHIPhoop stress or internal pressure is the major element in the design of pipe system, the selection of materials being dependent on their resistance to internal pressure. With Polyethylene hoop stress can be calculated using the applied pressure on the sectional wall thickness of the pipe, or using AS/NZS 4130 as reference, the hydrostatic strength hS required is then expressed in MPa. Based on the required working pressure the minimum wall thickness can then be calculated.

� = P (de – emin ⬚ )

2emin ⬚

Where P = pressure and e = wall thickness

The limit of hydrostatic strength hS can be taken from the regression curve figure 2.0 when assessing the design and MAOP.

RING STIFFNESS AND PIPE DEFORMATION SN is a value for pipe stiffness arrived at by experimentation, that the pipe is compressed between parallel steel plates and a value is arrived at by the force versus given deflection percentage over a specified length in kN/m/m, for example SN 16 = 16000 kN/m. The design performance however is dependent on external factors such as environmental conditions, service conditions and time, referring to AS/NZS 5065

Ring Stiffness or Specified Tangential Initial Stiffness (STIS) is a design element that can also be considered in relation to SDR. As the SDR ratio increases comparatively the stiffness of the pipe reduces by the third power, when we consider the formula for ring stiffness.

STIS = 1/12.Eo.1/(SDR –1)³

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HYDRAULIC DESIGNPolyethylene and Polypropylene pipes compared to other materials are considered hydraulically smooth, ensuring less pressure loss through pipes of equivalent diameter. Typical Colebrook-White roughness coefficients, k, for concentrically joined clean water supply pipes:

STRUCTURAL DESIGNStructural design of PE and PP pipes is done according to AS/NZS 2566.1. As with any flexible pipe, the embedment material has to fully enclose the pipe, be of correct particle size and compactable. The better compaction is, as well as the higher is the modulus of native soil, the higher are the loads the pipe can accommodate. Only for covers more shallow than 0.5 m the strength of the pipe itself becomes the defining factor in the design. The standard also specifies typical minimum covers for various pipeline locations, trench and embedment dimensions, some design live loads.

design notes

Fig. 6 Figure 4.0 Trench and embedment geometry

TABlE 2 Table 2.0 Colebrook-White roughness coefficients, source AS 2200

Material k,mm

Plastics like PE, PP, PVC 0.003 – 0.015

Steel cement lined 0.01 – 0.06

Ductile Iron, steel, epoxy lined 0.01 – 0.03

Concrete 0.03 – 0.15

INSTALLING OF ThE PIPE W

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INSTALLING OF THE PIPEPolyethylene and Polypropylene are flexible materials that are strong, resistant to impact and abrasion, offering a number of advantages in regard to the ease of installation: coiled or fusion welded PE pipes allow for a greater number of options in regard to installation methods, such as trenchless installation, twin-wall PP pipes are lightweight accellerating installation in rough conditions.

Open-trench installation process is guided by recommendations of AS/NZS 2566.2 and AS/NZS 2033. The latter standard also highlights above-ground installation of PE pipes - standard black pipes can be installed where direct sunlight exposure is expected.

JOINTING OF POLYETHYLENE PIPECommon methods like butt welding and electrofusion fitting welding of PE pipes involve jointing the pipes under controlled temperature, time and pressure conditions. Ductile weld creates a joint having approximately the same strength and characteristics as the parent pipes Twin-wall PP pipe joints incorporate eleastomeric rings ensuring water tight connection in gravity drainage and sewerage systems.

Other methods of jointing are also available for both PE and PP pipes including mechanical fittings, flanged connections to valves and pipes of other materials.

TABlE 3 Table 3.0 Advantages and disadvantages of Plastic Pipe Materials

Material Advantage disadvantage

HdPE/PP • Flexible so does not require as many fittings for bends• Does not require the pipe to have constant falls so will

follow ground contour• Seldom requires thrust blocks or additional bracing • Black pipe is UV stable so can be used above ground in

direct sunlight• Abrasion resistant so can deal with course bedding

material• Being elastic has greater tolerance for surging and water

hammer• highly resistant to ground shear and seismic movements• Can be installed using trenchless methods

• Dense in proportion to mechanical strength so is consequentially heavier

• Requires specialist welding equipment

gRP • Less dense so is a comparatively lighter pipe in proportion to MOP

• handles higher pressures• Does not require specialist assembly equipment• Readily available in large bore sizes

• Requires additional cost of thrust supports to counter axial forces and surges

• Needs careful installation in regard to leveling and alignment

• Requires additional fittings for bends

PVC • Less dense so is a comparatively lighter pipe in proportion to MOP

• Does not require specialist assembly equipment

• Requires thrust supports to counter axial forces and surges in larger diameters

• Needs careful installation in regard to leveling and alignment

• Requires additional fittings for bends

Fig. 7 Butt Fusion weld Fig. 8 Electrofusion coupler welding Fig. 9 Mechanical Jointing Fig. 10 Rubber Ring Joints

Polyethylene economics

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POLYETHYLENE ECONOMICS As detailed in standards AS/NZS 4130 and AS/NZS 5065, it is possible with a very high degree of reliability to forecast the service life of correctly designed, produced, installed and maintained PE and PP pipes to be not only 50 years of design life but to last 100 years and beyond.

SERVICE LIFE OF PE IN THE FIELDhDPE and PP should be a considered a very tough and forgiving material. Consequentially operational factors such a water hammer, where the pipe system has been adequately designed should not have a negative impact on service performance. however, care to be taken around handling and installation of PE pipes in the field as this has a considerable impact on the pipes service life.

Mechanical impacts and abrasion should be avoided due to the effect of notching the pipe which may lead to crack propagation. Abrasion should also be considered in regard to the cleanliness of the inside of the pipe, where sand, stones and foreign materials damaging the interior walls may also initiate premature crack failures. Avoidance of damage should be considered a more cost effective solution as opposed than over design of the pipe system to allow to a margin to cover damage.

WHOLE LIFE COSTSGiven the expected long service life and large investments in pipe systems then, when comparing materials, the ‘value proposition’ should be considered in terms of relationship of combined total installed costs + operational costs + maintenance costs to total conveyed fluid volume + expected lifetime.

For example, a PE pipe may have a higher metre cost than steel pipe, but has no costs associated with corrosion protection or maintenance, and has a lower roughness coefficient, allowing for a greater volume of fluid to be transported in similar sized pipe, and a longer lifetime (referring to table 4.0) before major rehabilitation is required. The long term view is highly likely to finally be in favor of the selection of Polyethylene pipe.

COMPARATIVE INSTALLATION COSTS Installation costs like whole of life costs should be viewed as a total cost package, with the value of hDPE and PP being assessed collectively alongside transport, assembly of pipe strings, trenching and backfill operations. Factors such as the soil conditions, concrete bracing, water table, available trench fill quality and even project delay risks need to also be factored into installation costs.

Studies have found where an aggressive environment exists outside of the pipeline, for example poor backfill quality, rocks and gravel, high ground shear and high mineral salts, then the characteristics of hDPE, high abrasion resistance, flexibility, resistance to chemical corrosion, provide a distinct advantage in ‘whole installation cost.

Case 1 = unstable soil conditions, soft soil, high water table

Case 2 = stable soil with aggressive environment outside the pipeline

In regard to pipe selection there is no perfect pipe material, with each material listed having its own merits or suitability to a particular operational or installation environment. Waters and Farr seeks the best outcome on behalf of its clients in terms of material selection, taking into consideration all ‘whole life factors’ and leveraging a complete portfolio of available pipe materials.

TABlE 4 Table 4.0 Source: Polyethylene Pipe E Grann-Meyer 2005

Material Service life Conditions

hDPE >100 years Normal Conditions

Steel 30-50 years Normal Conditions

Ductile Iron 30-50 years Normal Conditions

GRP 25- 50 years Normal Conditions

Concrete 25-50 years Normal Conditions

Material Cost Case 1 Cost Case 2

hDPE 100% 100%

Steel 100-105% 120-130%

Ductile Iron 95-105% 120-125%

GRP 90-100% 100-125%

Concrete 110-120% 130-135%

Source: Polyethylene Pipe E Gran-Meyer 2005

www.watersandfarr.co.nz 0800 923 7473

Waters & FarrTechnical Product Catalogue

Issue: March 2017