Y our V alue P art ner - Marley Pipe Systems (A) Min Thread Length mm DN

WeholiteManual

© Copyright Marley Pipe Systems (Pty) Ltd 2014

www.marleypipesystems.co.za

Y o u r V a l u e P a r t n e r

01

Marley Pipe Systems has been manufacturing SABS approved products since consumer protection was first mandated in the industry.

In keeping with international trends, Marley is a market leader in converting to lead free materials.

Marley’s commitment to quality and safety has all pipes and components manufactured in an ISO9001 accredited facility.

About Us

Vision

To become the preferred and most respected distributor and manufacturer of quality plastic pipe systems for the Building, and Mining and Industrial markets in sub-Saharan Africa.

PurposeTo grow responsibly towards becoming a truly regional (sub-Saharan Africa) player represented in major centres, manufacturing fast moving product ranges at local plants across the region as well as providing a wholesale offering on group and externally produced products.

Values• Integrity

• Honesty

• Passion

• Reliability

• Trust

• Accountability

• Compassion

• Professionalism

• Respect

• Commitment

• Excellence

• Ethics

Your TRUE Value PartnerMarley’s dedicated Mining & Industrial Division leads the way with value driven pipeline solutions that are proven to improve efficiency, solve key industry challenges, and ensure safe and sustainable operation in a broad spectrum of demanding applications.

Our diverse product offering, technical capabilities and quality assurance credentials enable us to meet the specific requirements and operating environments that exist in each of the industries we serve. This is also backed by a plethora of value-added services, including delivery, on-site support and product training to ensure that best practice is implemented, and thus safeguarding the quality of installations.



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About Us

03

Introduction

Introduction to Weholite Polyethylene is recognised by clients and engineering consultants alike as the ideal pipe material for many pressure and non-pressure applications – from water distribution to gravity sewers, rehabilitation projects and manholes to marine pipeline applications.

Recognising clients’ needs for large diameter, lightweight, low-pressure pipes and fittings, Marley now offers Weholite. Constructed by a unique patented structured wall process, Weholite can be manufactured in a range of ring stiffnesses and large pipe sizes from 280mm up to 3500mm – depending on customer requirements.

Weholite is manufactured in Finland, Sweden, Poland, South Africa, the United Kingdom, Canada, Malaysia, Oman, Iceland, Italy, Chile, Japan and Thailand and is steadily gaining ever wider acceptance in other countries worldwide.

04

Landfill Drainage

1500mm Weholite shaft with stepladder and Solid-Wall HDPE piping. Landfill drainage site, Gauteng.

Attenuation Application

Stormwater attenuation application.

Marine Pipeline Application

Mine Drainage

300mm Weholite pipe perforated for mining drainage pipe.

Fittings/Specials

Weholite Applications

Standard conditions of tender and sale apply. A copy of these conditions can be forwarded upon request

05

Weholite Structured Wall HDPE pipe provides all the technical advantages of equivalent polyethylene Solid-Wall pipes, but with substantial savings in weight, thus combining greater ease of installation with increased cost effective-ness when compared to traditional materials.

New production techniques have been combined with the latest raw materials technology to produce a durable pipe system with superior load-bearing properties, making Weholite the preferred solution for many municipal and indus-trial applications in both the public and private sector – including stormwater management, sewage treatment systems, culverts, marine pipelines and irrigation water distribution.

Sewer Pipelines

1250mm outfall sewer. Blackburn, Durban.

Stormwater

3m x 700mm stormwater pipe lengths being laid in Cullinan.

Pipe Rehabilitation

Rehabilitation of a corrugated galvanised pipe.

Culverts

Weholite has railway certification in various countries.

Weholite Applications

06

SWP (Structured Wall Pipe) WeholiteMarley manufactures Weholite pipe under licence from Uponor Infra (formerly KWH Pipe). Weholite pipes are manufactured in accordance with Uponor Infra and Marley internal standards which are in accordance with EN 13476 and SANS 21138 and form part of an SABS ISO 9001:2008 quality manage-ment system. Regular inspections and audits are carried out by the local inspection authority.

The pipe design allows for a minimum design life of 50 years under specified design and installation parameters. The material selection process is the same as that used for pressure pipe applications. Research has shown that the service life of Weholite will be at least 50% greater than concrete, and in corrosive applications, at least 100% greater than concrete.

Weholite pipe sizes:

Weholite structured wall HDPE pipes are supplied as follows:

Product Range & Dimensions

Stiffness design is according to ISO 9969

Stormwater

Pipe CD/ID (mm) Max Pipe OD (mm) 2kN/m2

Max Pipe OD (mm) 4kN/mm2

8kN/m2

Max Socket OD (mm)

SewerSandtight male-female coupling, no seal = OGEE joint

280300350400450500560600700750800900100011001200125015001800

Standard lengths 3m, 6m, 12m

Standard lengths 6m, 12m(24m pipes may also be specified)

Threaded joint* DN≤1200mm pipes

318334285439484555616665765840878980110511771305135016852022

3183414044545055656386777908409031016112812541354140016852022

390415476526576636708747865919980*N/A*N/A*N/A*N/A*N/A*N/A*N/A

Sizes larger than 1800mm upon requestDimensions are indicative and may change from time to time1. For watertight joint, pipes need to be extruder welded / LP couplings may be used on plain ended pipe2. Subject to availability

Watertight socket and seal for pipe sizes less than or equal to DN 800, alternatively pipes welded in situ or LP couplings can be used

StormwaterFemale socket, sandtight (geotextile may be required)

280-800mm Sewer PipeSocket with seal – watertight

Threaded Joint Details:(Sandtight) Welded for watertightness

Nominal Size DN/ID

(A) Min Thread Length mm

DN<500500560600700750800100011001200

100130146155170175180200200240

Product Range & Dimensions

07

A

B ≥ 0,5 Profile Height ≤ 0,75 Profile Height

B

Threaded Joints*Subject to availability

08

Flange JointsDouble-socketed standard fitting

Double Sockets

JointDNmm

Bolts pcs

x size

Bolts Torque

NmDemm

NS=dimm

Demm

Dmm

bmm

hmm

d4mm

kmm

Lmm

280300350400450500560600700750800

315338400450505580618675788844900

280300350400450500560600700750800

Dimensions are calculated values and may vary from the finished productFlange drillings are dimensioned according to customers’ requirements

Weholite PE Pipe Stub EndFlange

377377377385380379390390400410415

4124125055656706707808358959551015

2222283236385040505056

350350376430473515691703725770815

12xM2012xM2016xM2016xM2420xM2420xM2420xM2720xM2724xM2724xM2724xM30

34384560657086889095100

3434404444445056566070

320320430482485485685685805853900

280280355400450500560360710710800

NS = dimm

280300350400450500560600700750800

Demm

315338400450505560618675788844900

Lmm

6286847407968309169601042116611801200

Mmm

199206220248278308240371433442450

Do mm

364388438488550602660705830900944

09

Bends

Double-socketed Standard Fittings

NS=Dimm

demm

R = 1,0 x NSmm

30°Z

mm

Dimensions are calculated values and may vary from the finished product. Tolerances for pipe lengths Z and Ze are ±50mm (+23°C). Other angles and bend radii can be supplied on request.Dimensions above 1800mm will be designed individually to meet customer requirements, transport possibilities, etc.

Zemm

45°Z

mm

Zemm

60°Z

mm

Zemm

90°Z

mm

Zemm

280300350400450500560600700750800900100011001200125015001800

3153384004505055606186757888449001013112512401350157516802016

280300350400450500560600700750800900100011001200125015001800

267312357402450499550602703730758858935104910129119751170

81126173157175191191231270379308487385678464540604799

35241247253259066173079793198010181118126013441402136514601752

16622625228431535337142649862946874771097385299410891381

33136142154155757269281194799210371160128313571430139814951794

23524426129633136540344051455158766073380788093011001300

47354762169575086590010411215125013441443166717091891193620732488

309355401447500557620670782820894

1000111712001341140017002000

Bends 1° - 30° Bends 31° - 60° Bends 61° - 90°

10

Equal Tees

Double-socketed Standard Fittings

NS 1mm

Z 1mm

de 1mm

de 2mm

NS 2mm

For branches (NS 2<NS 1), lengths Z3 and Z3e are equal to above. Dimensions are calculated values and may vary from the finished product. Tolerances for pipe lengths Z and Ze are ±50mm (+23°C).Dimensions above 1800mm will be designed individually to meet customer requirements, transport possibilities, etc.

Z 2mm

Z 2emm

Z 3mm

Z 3emm

280300350400450500560600700750800900100011001200125015001800

3153384004505055606186757888449001013112512381350157516802016

3153384004505055606186757888449001013112512381350157516802016

280300350400450500560600700750800900100011001200125015001800

365424483542600674750812947100010381150128413621431140015001800

365424483542600674750812947100010381150128413621431140015001800

2262382632943253663914415766296677799139911060102911291429

365424483542600674750812947100010381150128413621431140015001800

226238263294325366391441576629667779913991

1060102911291429

11

Manholes

Manholes - Lateral

Di(ID)

Z1

X oX o

SHAFT

HDPE STEPS

BENCHING

di(ID)

Manholes - Reducing

X o X o

HDPE STEPS

SHAFT

BENCHING

Z1

Z2

Di(ID)

Socket and seal included all round

Manholes - Straight or Bends

SHAFT

HDPE STEPS

BENCHING

Z1

Z2

di(ID)X o

X o

Di(ID)

Z1 = 1,5mDi(ID) = 1200mmdi(ID) = 497mmSocket and seal included all round

X = 15°Z1 = Z2 = 1,5mDi(ID) = 1200mm

X = 15°X = 15°Z1 = 1,5mDi(ID) = 1200mmdi(ID) = 497mmSocket and seal included all round

Marley offers custom fabricated HDPE manholes for a variety of applications in high water tables and/or dry conditions, manufactured from a combination of high quality solid-wall and structured wall pipe. Marley HDPE manholes are resistant to root ingress, preventing contamination to surrounding groundwater and providing a watertight structure that delivers an extended life expectancy, making them suited to sewer and stormwater applications as well as for telecommunications.

Marley’s HDPE manholes are prefabricated, which eliminates the risk of deformation in the structure, however, the shaft configuration of the manhole can also be adapted to accommodate any application separate from the full plastics system. HDPE ladders can also be fabricated inside the manhole upon request. Standard covers and frames are also available.

Standard conditions of tender and sale apply. A copy of these conditions can be forwarded upon request*Drawings are indicative and can or may be changed

LP Couplings

Dimensional Data

Table Dimensional Data

Width

T

LP Coupling Components

Components

123456789

1011121314

Component Description

EThe Weholite LP Couplings, manufactured by Thomas Pipe Products, are designed and manufactured specifically for use with Weholite pipes. They are suited for low pressure, large diameter applications such as sewer, gravity or stormwater pipelines. They are made from Stainless Steel with a Vulcanised Rubber Seal. Due to high-quality Rubber Seal and Stainless Steel construction components, Weholite LP Couplings have a design life of over 50 years, if installed correctly.

Advantages• Extended life expectancy• Proven technology ensures the accommodation of ground settlement• Cost-effective• Easy to install• Light weight• Leak tight• Corrosion resistant

PipeCD/ID(mm)

Max. Pipe OD

2kN/msq (mm)

Max.Pipe OD4kN/msq8kN/msq

(mm)

Width(mm)

T(mm)

Width(mm)

T(mm)

280300350400450500560600700750800900100011001200125015001800

318334385439484555616665765840878980

110511771305135016852022

3183414044545055656386777908409031016112812541354140016852022

300300300300300300300300300300300300300300300300300300

141414141414141414141414141414141414

Available Only on Request

400400400400

15151515

Component Name Specification for Material of Construction

123456789

1011121314

T-washerCaptivated T-bolt headBolt loopT-bolt shankBolting hookLocating spacerFlat washerHex nutWorm driveElastomeric sealRubber guideOutside clamping bandSealing ribInner clamping band

Stainless Steel AISI 304 or 316Stainless Steel AISI 304 or 316Stainless Steel AISI 304 or 316Stainless Steel AISI 304 or 316Stainless Steel AISI 304 or 316Polyethylene 300Stainless Steel AISI 304 or 316Stainless Steel AISI 304 or 316Stainless Steel AISI 304 or 316EPDMEPDMStainless Steel AISI 304 or 316EPDMStainless Steel AISI 304 or 316

When connecting large diameter pipes, it is imperative to ensure the coupling width is sufficient to handle the effects of thermal expansion and contraction, and handling damage that may be inflicted on the pipe end. In light of this, the Weholite LP Coupling is designed in widths of 300mm and 400mm, ensuring a leak-proof seal extending well beyond the pipe end.

12

High Density Polyethylene as a Material for Pipe ConstructionHDPE has long been considered ideal for sewer applications. Owing to the economic advantages of structured wall (or profiled-wall) technology, Weholite HDPE pipe can now be used as an economic alternative to traditional materials such as vitrified clay, reinforced concrete (R/C), fibre cement (F/C) pipes and corrugated galvanised steel.

Designing with Weholite

Inherent Properties of Weholite Structured Wall Pipe

Typical physical properties of Weholite pipe materialBelow, typical values can be used to perform structural design as per EN 1295-1.

PropertyDensityE-modulus short termLinear expansion coefficientThermal conductivityPoisson’s ratio

Unit Value Standardkg/m3

N/mm2

Mm/mM.k.W/m°C

>9301000

13 x 10-5

0.3 – 0.40.4

ISO 1183ISO 527

Corrosion and Chemical Attack Traditional pipe (concrete) materials may suffer from bacterial or chemical attack in a corrosive environment (such as that encountered in sewer and effluent lines). HDPE is highly resistant to such attacks, making Weholite an ideal alternative for long pipe service life.

For all practical purposes, PE is chemically inert in normal use. Electrolytic and galvanic corrosion are therefore eliminated. More information on the chemical behaviour of PE is given in ISO 10358.

Abrasion

In the Darmstadt abrasion test (DIN 19534, Part 2), samples of commonly used pipe materials were filled with a mixture of sand and water and subjected to a specified number of rocking cycles. The amount of abraded material was measured at regular intervals. The result proved the very high abrasion resistance of polyethylene pipe material – 400 000 load cycles resulted in 0,3mm abrasion for PE pipes. Abrasion in fibre-reinforced and concrete pipes was 6-8 times higher.

0

0,5

1,0

1,5

2,0

2,5

3,0

200 000 400 000 600 000

Load cycles N

Abr

asio

n (m

m)

Asbestos cement pipe

Fibre glassreinforcedpipe

Concrete pipe

PVC

HDPE

Clay Pipe

13

Scale and Sediment Build-upHDPE does not readily bond with or adhere to other materials. This ensures that build-up does not occur, and long-term flow characteristics are not affected when Weholite is specified.

Inherent Properties of Weholite Structured Wall Pipe UV Stability and Temperature RangeIn accordance with international material standards, the HDPE grades used in Weholite production may be UV stabilised by the addition of carbon black, making Weholite almost impervious to UV attack.

The maximum permissible temperature of the medium transported is:+80°C (short term) and+45°C (long term)

Product Advantages Weholite has an effective double wall, ensuring system integrity should the pipe be damaged either externally or internally.

12m lengths offer a greatly reduced joint frequency, which minimises the possibility of leakage or ingress of groundwater (which can lead to excessive loading of downstream treatment plants).

Weholite offers superior crack resistance due to the ability of the material to “unload” excessive stress on to the surrounding backfill. Such stresses (often caused by soil movement) could result in failure of pipelines assembled with rigid materials such as concrete and fibre cement.



14

*Technical Specifications of HDPE Raw Material

Weholite Flow Calculation Hydraulics

Owing to the low friction coefficient of HDPE, the coefficient of friction of Weholite pipes is relatively low.

COLEBROOK-WHITE k = 0.03mmMANNING m = 0.01HAZEN WILLIAMS C = 149

These figures are generally below those obtained with new reinforced concrete pipe, and no adjustment (to allow for corrosion, etc.) is required with Weholite pipe designs (20% - 30% lower than used for concrete).

Hydraulic DesignColebrook-White Formula

Weholite High Density Polyethylene (HDPE) Resin

DensityMelt Flow Index (190C/21,6kg)Melt Flow Index (190C/5kg)Vicat Softening Point (5kg)Crystalline Melting RangeViscosity Number

Shore D HardnessTensile YieldUltimate Tensile StrengthUltimate ElongationElastic ModulusFlexural Strength (3.5% Deflection)Notched Impact (Charpy) 23°CNotched Impact (Charpy) -30°CThermal Stability (OIT1, 210°C)Carbon Black Content

Mechanical Properties

ISO 1183ISO 1133ISO 1133ISO 306

ISO 3146-85ISO 1628

ISO 868ISO 527ISO 527ISO 527ISO 527ISO 178ISO 179ISO 179

ISO 10837ASTM D 1603

0.9589.00.2367

130-133390

612435

>600900-1000

19206

≥20≥2

g/cm3

g/10 ming/10 min

°C°C

cm3/g

MPaMPa

%MPaMPaKJ/m2

KJ/m2

Min%

1) OIT: oxidation induction time* Alternative materials may be used from time to time


ʋ = kinematic viscosity (m2/s)d = internal diameter (m)g = acceleration due to gravity (9.81m/s2)u = velocity (m/s)l = hydraulic gradient (‰)k = roughness coefficient (m), Weholite pipe 0.03mm

15

Physical Properties


16

Discharge (ℓ/s) for Pipes with Full Flow• Roughness coefficient value for Weholite pipe 0.03mm• Roughness coefficient value of 0.25mm for the pipe system (diagram)• Kinematic viscosity of water at +10°C


Weholite Loads on Buried PipesIn the case of low-pressure or thin-walled pipes, it is frequently not the internal pressure but the external pressure which dictates the pipe wall stiffness. A pipe is less resistant to external loads than to internal pressure, as the pipe wall acts in a different way. Whereas internal pressure exerts pure tension on the pipe walls, external loads may cause circumferential or longitudinal bending, arching and even buckling.

External loads are not symmetrical; the vertical loading due to soil pressure or superimposed loads is greater than the lateral soil pressure. It is this differential loading which causes bending of the pipe wall.

Possible loads on a pipePipelines are typically subject to:

a. Vertical soil pressureb. Superimposed live loads due to vehiclesc. Crushing or bending by heaving or moving soils

Causes of pipe failureExcessive loads may result in failure due to:

a. Crushing or compression of the pipe wallb. Tensile failurec. Bending of the pipe walld. Longitudinal bendinge. Excessive deflectionf. Bucklingg. A combination of any of the above

Flexibility in Buried PipelinesA flexible pipe is by definition a pipe which will deflect when subjected to external loads (traffic, ground water changes, soil settlement, etc.) as opposed to a rigid pipe, which carries all external loads by itself. The degree of deflection of a flexible pipe will depend on the pipe stiffness, support from the surrounding soil and external loads.

There are several methods for calculating the deflection in buried flexible pipelines. Most of them are based on the so-called Spangler Formula:

After installation, further gradual compaction of the surrounding soil takes place due to external loading and soil settlement. Experience shows that the maximum deflection will be achieved within 1-3 years after installation, depending on backfill material, the quality of backfill compaction work and on external loads. The maximum allowable deflection is 8-10% (pipe and welded joints only) and 3-5% (joints).

A flexible pipe absorbs external loads and deforms to a certain extent. A rigid pipe, on the other hand, by definition cannot deform. When external loads increase sufficiently, the rigid pipe will finally crack, after which it starts to behave like a flexible pipe.

Pipes installed underground react to soil settlement along the length of the pipeline. Loads/deflections vary from place to place. Flexible pipes react to additional settlement/loads by bending, while rigid pipes react by angular deformation in the joints.

17

Loads on Buried Pipes

Deflection (%) =vertical load on the pipe

pipe stiffness + soil stiffness

Loads on Buried Pipes

For alternative soil types, refer to table below. For reference:In accordance with pr EN 1046, A 127 and WG 14, the following soil types and groups have been proposed by G. Leonhardt 1998/02/02 based upon recommendations given in British Standard BS 5930 and German Standard DIN 18196:

Group 1: poorly graded gravel, single sized gravelGroup 2: granular soils, such as well-graded gravel, gravel-sand mixture, single sized sand, well-graded sand, poorly graded sand-gravel mixtureGroup 3: mixed grained soils with low fine fraction and some cohesion such as silty gravel-sand mixture, clay-like gravel-sand mixture, silty sand, clay-like sandGroup 4: mixed grained soils with high fine fraction moderate cohesion such as very silty respectively clay-like gravel-sand mixture, very silty respectively clay-like sand, silt of low plasticityGroup 5: fine grained cohesive soils such as inorganic silts respectively clay, grained soils with a mixture of humus or chalk, organic silt, organic clay

If a structural design is required, e.g. in cases where no other information exists, then a method as defined in EN 1295-1 should be used. A Marley representative can also be contacted to assist through manipulation of variables in a finite element design software package.

Initial Average Pipe Deflection % for Well Performed Procedure at Depth of Cover 6m

Soil

Group ShortTerm

ShortTerm

Max Max MaxShortTerm

ShortTerm

ShortTerm

ShortTerm

% Deformation

2 kN/m2 4 kN/m2 8 kN/m2

12345

Ave1.72.02.43.23.6

Ave1.61.82.22.93.2

Max2.42.73.34.44.8

Long3.23.64.45.86.4

Ave1.41.61.92.42.6

Max2.12.42.93.63.9

Long2.83.23.84.85.2

Max2.63.03.64.85.4

Long3.44.04.86.47.2

18

DesignThe design requirements of Weholite allow the engineer an optimum combination of pipe strength and flexibility, and installation savings are normally easily achieved compared with rigid materials.

Loading / DeflectionUnder loading, flexible pipes deflect, and Weholite (which is viscoelastic) reacts similarly. Deflection is vital, as it optimises the pipe/soil interaction and ensures a crack-free system. Rigid materials cannot interact with soils and have to bear loads entirely, irrespective of soil stiffness. It is important to contain deflection.

Three standard ring stiffness classes exist; 2 kN/m2, 4 kN/m2, 8 kN/m2 are applied as follows. Stiffness design conforms to ISO 9969:

Ring stiffness,

Where Eo = 1000 N/mm2

I is calculated from the geometry of the true profiled wall Dm = Mean diameter of pipe

Design graph for pipe selectionBased on the study (TEPPFA; 1999; Design of Buried Thermoplastics Pipes), several design approaches can be proposed. For thermoplastic pipes possessing huge strainability, designs can be kept simple. It has also been shown that more effort should be put into the installation of the pipe, but not more than for rigid pipes. An important observation is also that flexible pipes follow the soil settlement, and behaviour is managed by this. Load is therefore not an issue for flexible pipes in well installed conditions. Therefore, based on the results of this work, the design approach using simple graphs is strongly recommended.

In the design, graphs-areas are given for each installation group. The lower boundary of each group represents the average deflection expected and upper boundary the maximum.

The design graph contains three installation groups. The add factors are fully linked to the type of installation. The add factors or consolidation factors (Cf) have to be added to the value for the initial deflection which can be obtained from the graph.

Installation TypesAs per ISO TC 138/sc1 and / or ENTS 13476-3

WellPrimary backfill: granular typeLayer 30cm + compactionFinal backfill: soil of any type + compactionCompaction: >94% mod. Proctor

ModeratePrimary backfill: granular typeLayer 50cm + compactionFinal backfill: soil of any type + compactionCompaction: 87 - 94% mod. Proctor

NoneBackfill:granular /cohesive typeLayers: without compactionCompaction: <87% mod. Proctor

D3m

RS ISO = EoI

Moderate

Cf = 2,0

None

Cf granular = 3,0Cf cohesive = 4,0

Well

Cf = 1,0

See section on Pipelaying for more information on the validity of the design graph.

19

• Determine installation type. • Determine consolidation factor (Cf) in accordance with installation type.• Determine maximum short-term allowable deflection.

Example:

(δ/d) final = (δ/d) instantaneous + Cf

Thus (δ/d) instantaneous = (δ/d) final - Cf

Thus for a joint 2 kN/m2 pipe 3% long-term maximum allowable deflection for well performed installation is as follows:

3% - 1% = 2%

Or maximum allowable for moderate performed installation

Thus 3% - 2% = 1%

Both conform to maximum stated in “Joints with or without rubber seal”.

Weholite Design Methodology• Ensure that Weholite pipes and variables comply with variables referred to in the section on Pipelaying (Validity of the Design Graph).• Determine national long-term maximum allowable circumferential deflection % (Either pipe or joint will prevail).

Example:

BucklingDuring the construction phase – before side fill is compacted and soil stiffness is attained – the pipe is subjected to full loading without support of the side fill. A buckling check is done according to the graphs below. Buckling loads should never exceed 50% of the predicted buckling strength (i.e. a safety factor of 2 against buckling must be observed).

For a firmly buried pipe, the buckling pressure Pbs can be determined as:

where:Pbs = Buckling pressure (MPa)SN = Ring stiffness (MPa)E’t = Tangent modulus of the soil (MPa)n = Safety factor (normally ≥2)

The value is theoretical limit. Under normal circumstances, the safety factor against radial buckling should never be less than 2.

Tangent Modulus for Friction Soils

Calculation example• Groundwater table below pipe• Filling height = 3m• Degree of compaction = 90% mod. Proctor• Ring stiffness of a pipe = 4 kN/m2 = 0,004 Mpa f

from a table E’t = 2,5 MPa

Pbs = 5,63 √( 0.004 * 2.5)= 0.563 MPa

Pperm = 0,563/2= 0,28 MPa

Pipe and extrusion welded joints / Threaded joints

Short Term Long Term

Long TermShort Term

Joints with or without rubber seal

2 kN/m2

4 & 8 kN/m2

2 kN/m2

4 & 8 kN/m2

5%8%

2%4%

3%5%

8%10%

Pbs = 5,63 √ SN•E’t

Pperm = Pbs

n


90 % mod. proctor

Ground water table below pipe

3,0

2,0

E’t (Mpa)

1,0

0 1 2 3 4 5 6 7Filling Height

H (m)

90 % m od. proctor

85 %80 %

75 %

85 %

80 %

75 %

3,0

2,0

E’t (Mpa)

1,0

0 1 2 3 4 5 6 7Filling Height

H (m)

20

Handling and Storage InstructionsRelevant national or local regulations must be observed.

GeneralWeholite pipes are sturdy and lightweight, which makes them easy to use. Unfortunately, these proper-ties also increase the temptation to abuse the pipe. Proper handling is required to minimise the risk of damage.

Pipes must be handled with sufficient care. They can be damaged if dropped or thrown about. Pipes or bundles of pipes must never be dragged – the pipe surface may be weakened by scratches.

When transporting and storing pipes, care must be taken not to permanently deform the pipes. Socketed pipes in particular must be stored in such a way that their sockets are not subjected to loading that will cause deformation.

Transport and unloadingPipes should be transported on flat transport beds without sharp edges or other projections that might damage the pipes. Movement or rubbing of pipes during transport must be prevented, for instance by strapping the pipes down. When pipes of different sizes are transported, the heaviest lengths are loaded underneath. If the pipes are transported nested inside one another, the smaller pipes are removed first and piled separately.

Upon arrival at the site, the pipe shipments are visually inspected and checked against the packing list for correctness in size, stiffness and quantity.

The pipes must also be inspected for damage which may have occurred during handling and/or transport. Obvious damage such as cuts, abrasions, scrapes, tears and punctures must be carefully inspected and noted. Any damage, missing items, etc. must be noted on the bill of loading and signed by the customer and the driver. Shipping problems such as the above should be reported to the supplier immediately.

21

Correct loading and unloadingIt is important that loading, unloading and handling be performed safely to avoid damage to property or equipment. As loading and handling can be a hazard to persons in the unloading area, unauthorised persons should be kept at a safe distance while unloading.

Adequate level space must be reserved for unloading. Secure the truck on level ground as well. The unloading equipment must be capable of safely lifting and moving the pipe, fittings, fabrications, etc.

Off-loading may be done by means of skid timber and strap slings or with mechanical lifting devices. However, lifting chains, ropes or hooks may not be used, as these may result in permanent damage to the product. Lifting points must be well spread and evenly spaced.

Single PipesWhen lifting single pipes, use pliable straps or slings. Do not use steel cables or chains to lift or transport the pipe. Pipe sections can be lifted with only one support point, but especially for larger diameters it is recommended to use two support points to make the pipe easier to control. Do not lift the pipes by passing a rope through the centre of the pipe end to end.

Weholite Pipe Handling

Nested PipesAlways lift the nested bundle by at least two pliable straps. Ensure that the lifting slings have sufficient capacity for the bundle weight. Stacking of nested pipes is not advised unless otherwise specified.

StorageInspect all materials carefully upon arrival on site and note and report any defects immediately. All pipe stacks must be made on firm, flat ground that can support the weight of the pipes and lifting equipment. For safety and convenience of handling, the stack height for pipes is limited to five units or not more than 2.8m. Stacks must be adequately wedged to prevent movement.

Pipes must be stored on intermediate supports spaced not more than 2m apart. The support width must be greater than the profile width of the pipe size in question, but not less than 100mm. Pipes with integral sockets must be stacked with the sockets at alternate ends, or at least without loading the sockets. Pipes with z-cut ends must be stored with the z-cut oriented in the same position (at 12 o’clock). The maximum storage height for pipe stacks is 2.8m overall.

Besides protecting all material adequately against theft, vandalism, accidental damage or contamination, also keep pipes and fittings away from sources of heat if at all possible. If the pipes are to be stored for long periods, they must be protected against excessive heat; storage at high temperatures for prolonged periods can cause excessive deformation that may affect installation.

To avoid this risk, the following precautions are recommended:a. Shield the stacks against continuous and direct sunlight and allow free passage of air around the pipes;b. Store the fittings in boxes, sacks or shading manufactured so as to permit free passage of air;c. Protect elastomer sealing rings against direct sunlight.

Preferred lifting technique

Normal stacking of plain ended pipes

Stacking of socketed pipes

Weholite Pipe Handling

22

Weholite Choice of Stiffness (SN) Series

GeneralWeholite pipes are flexible pipes. A flexible pipe installed in the ground deflects during installation, because of the force exerted on it, as well as after installation, because of the further settlement of the soil. The amount of deflection reached after installation depends to a great extent on the quality of installation and to a lesser extent on the pipe stiffness.

The increase in the pipe deflection after installation depends on the amount the soil can settle after installation. When the soil around the installed pipe is well compacted, any increase in pipe deflection will be very limited. If the soil compaction ratio is low, pipe deflection will increase during settlement. Traffic load does not affect pipe deflection other than increasing the rate of settlement of the soil.

Procedure for PipesPrescribing a specific level of workmanship is the surest way of controlling pipe deflection. It has been proven that this parameter has by far the greatest influence on deflection. If, however, the installation procedure is fixed, then the choice of stiffness class (SN) can be made on the basis of one of the following:

• When reference situations exist: Has the same class of pipe used under similar or more severe conditions been found acceptable?• Based on the Design Graph, see section on Loads on Buried Pipes and Pipelaying• Based on structural design, see section on Pipelaying

Procedure for FittingsGenerally, fitting in accordance with this standard should have the same stiffness class as the pipes to which they are connected.

Fittings in accordance with EN 1401-1, 1852-1 and 12666-1 can be used in combination with pipes according to this standard. Because these fittings are classified by their wall thickness, their actual stiffness is higher than that of a pipe with the same wall thickness. Such fittings are used as shown in the table below.

Where fittings of equal or higher stiffness than that of the pipe(s) are not available, fittings of lower stiffness may be used. In such cases, guidance from the fittings manufacturer or supplier should be sought.

Weholite Choice of Stiffness

Minimum fitting classes recommended for use with structured wall pipes

Pipe Stiffness

Fittings according to:

ISO 9969 EN 1401-1 EN1852-1 EN12666

SN 2SN 4SN 8SN 16

SDR 51SDR 51SDR 41SDR 34

S 20S 20S 16

S 11.2

S 16S 16

S 12.5S 10

SN 2SN 4SN 8

SN 16


23

Socket Jointing (Elastomer Sealing Ring Joints)The integral socket joint can be delivered as sandtight or watertight (with rubber seal). The rubber seal conforms to international standards and is resistant to normal sewage waters. Seals resistant to oil contaminated water are available upon special request.

Jointing must always be carried out in accordance with sound civil practice. However, in the absence of instructions the following is recommended:

a. Chamfer and deburr the spigot end when the sealing ring is in position in the socket.b. Use only sealing rings and lubricants supplied or approved by the manufacturer of the pipe or fitting.c. Ensure that cuts made on site are square. If necessary, set up a proper cutting zone. After cutting, chamfer or deburr the end to produce a finish equivalent to that of the pipe supplied by the manufacturer. Open profile closure needs to be repaired in pipes that will be air tested.d. Clean the pipe end, the socket and the sealing ring groove, removing any foreign matter, water, sand, dirt, etc. Make sure the sealing ring sits correctly in its location.e. Apply lubricant over the whole chamfered end, in the socket area or on the fixed sealing ring, as appropriate.f. Carefully align the spigot with the adjoining socket and push to the required insertion depth (depth of entry mark). If a lever is used on the pipe to push the joint, insert a block of wood between the lever and the end of the pipe to prevent damage to the pipe.

Weholite Jointing

1. Align the pipes vertically and horizontally

2. Make sure that spigot end, socket and sealing ring are free from sand, moisture, dust, etc.

24

4. Apply lubricant evenly onto the spigot end and the rubber sealing.

Welded JointsWelded and fused joints should always be made by qualified personnel and in accordance with the manufacturer’s instruction and national standards.Extrusion welding is used for gravity applications where the joints must have full watertightness and tensile strength, as well as 100% resistance to root encrease. Welding will be undertaken by specially trained operators either from the inside or the outside of the pipe, or both.

3. Install the rubber sealing ring in the groove. Make sure the tension in the rubber material is distributed evenly by applying force to the rubber ring.

5. Gently push the spigot onto the socket using adequate force until the stop mark (depth of entry mark) made on site is at the socket opening. Use a plate or plank to avoid damage to the spigot or socket. Large dimensions may be installed by using an excavator. Protect the socket opening with a sheet or plank. Check that the sealing ring stays in position.

Weholite Jointing

25

Connection to Existing PipesWeholite pipelines can be connected to existing pipelines or to structured wall pipelines of a different design in a way similar to a repair (see Repairs) by using an appropriate fitting. For saddle connections, follow the saddle manufacturer’s instructions.

Connection to Rigid StructuresA structure may be a wall of a building, an inspection hole, other pipelines, fittings such as valves or the like.

The connection of a Weholite pipe to a structure depends on the pipe size as well as on the structure at the connection point. Connections must be made in such a way that the joint is tight and that no damage is done to the pipe.

If a Weholite pipe is connected to a structure that may settle differently than the pipe, a flexible connection beneath the pipe in the vicinity of the structure must be used, or a transition zone permitting pipe movement, or a strengthening construction.

Special fittings for this purpose are available and must be fitted in accordance with the manufacturer’s instructions (short length double-socketed pipe).

RepairsSlip couplers or purpose-designed fittings are available for effecting repairs. It is recommended that the following general points should all be adopted, where applicable:

• The full extent of the damaged or failed section must be identified and removed.• The cut pipe ends should be square and prepared for push-fit jointing.• LP repair couplings should be placed in position on the exposed pipeline ends. The replacement pipe length should then be laid on the suitably prepared bed and the LP couplings moved into their final positions.• Ensure that the bedding does not interfere with the couplings and that the pipe ends are clean.

• Pull the couplings over the joint so that they are centrally located over the joints.• Check the line and level of the newly installed pipe.• Tighten all bolt tensioners evenly so that all the slack is taken up before tightening fully to 20-25Nm.• The embedment should then be replaced to give compaction values approximately equal to those immediately adjacent to the repair.• Prior to completing the backfill of the pipe, the bolts must be retensioned. Ideally, LP couplings should be retensioned on the morning after the repair has been carried out.

Wall Passings / Repairs

DETAIL A

CL OF PIPE

DETAIL A

CONCRETESTRUCTURE

BOX SECTION OF WEHOLITEPIPE CUT OUT AS SHOWN

26

Threaded Joints*1. Align the pipes vertically and horizontally.2. Make sure that the threads are free from sand, moisture, dust, etc.3. Thread the male end into the female end.4. The pipes can be rotated using a lever or band-sling.5. If necessary, an excavator can be used to help rotate the pipes. To facilitate the rotation, the pipes can be laid on planks or roller supports.

The joint as such is sandtight. If watertightness is required, the joint can be extrusion welded from the inside (NS>800mm), from the outside, or both. The joint can also be waterproofed using an external shrink sleeve or rubber sleeve.

*Threaded joints subject to availability.

Weholite Jointing

1

2

4

3

5

27

Rubber-sleeve JointsRubber-sleeve (LP) couplings are designed for jointing pipes in stormwater and other types of non-pressure applications in the construction, repair and maintenance of pipelines. These include:• Non-watertight jointing• As a joint for plain-ended pipes• Repair of existing pipelines• As an adapter between pipes of different sizes or materials

Fitting InstructionsWeholite LP CouplingStep 1:Pipe surface to be checked for damage.If the pipe end is in a suitable condition, it should be cleaned and marked with a line 150mm from the end.The pipe end must be liberally greased to assist the rubber sleeve to slide over the pipe end.

Step 2:The entire rubber sleeve must be pushed onto one pipe end.The two pipe ends must be positioned with a setting gap of 20mm.The rubber sleeve must be slid back over the 20mm gap between the two pipe ends. The gasket must be located centrally between the marks made on each pipe end.

Step 3:The first outer strap must be positioned and finger tightened in an outer groove of the rubber sleeve.

Step 4:The second outer strap must be positioned and finger tightened in the other outer groove of the rubber sleeve.

Step 5:The required size of socket (24mm) and the required torque rating (45Nm) is specified on the sticker by the fastening arrangement on the coupling.

Step 6:Tighten the outer bolts to the recommended torque rating of 45Nm.Tighten the inner-sleeve bolts to the recommended torque rating of 45Nm.

Step 7:Re-visit each nut to ensure the correct torque rating isachieved.

Step 8:The correctly assembled coupling should sit neat and straight, centrally located over the 20mm gap between the two pipe ends.

Weholite Jointing

1

2

3

4

5

6

7

8

28

DETAIL 1

DETAIL 3 - PLAN VIEW OF FINAL JOINT ALIGNMENT(LP COUPLING OMITTED FOR CLARITY)

DETAIL 2 - LP COUPLING CORRECTLY POSITIONED

SLIDE LP COUPLINGACROSS THE JOINTUNTIL IT IS EQUIDISTANTBETWEEN THE GUIDELINES

PIPE BEDDING TO BEREPLACED AND TAMPED

25 25

GUIDELINE

2nd PIPE PLACED IN TRENCH,WITH CORRECT HORIZONTAL

AND VERTICAL ALIGNMENT

LP COUPLING FITTED TO PIPEBEFORE PLACING IN TRENCH.APPLY LUBRICANT IF REQUIRED

PIPE BEDDING REMOVED LOCALLY

1 000

Deviation from straightnessIt is normal practice in sewerage and drainage that pipes are installed in straight lines. However, as Weholite pipes are longitudinally flexible, it is possible to bend them if required during the installation. In such cases, minor misalignments of the pipeline can be accommodated in the pipe itself by bending. The minimum permissible bending radius for Weholite pipes under normal installation conditions = 50 * De (outside diameter). There may not be any bending at the socket. An acceptable bending radius can be maintained by lateral supports against the side of the trench. Special care should be taken when bending pipes at low temperatures, and the joint must be protected against any extra stress.

The largest permitted angular deflection in the elastomer ring seal joint (the design angle) is

2° for de<315 mm1.5° for 315≤de≤630

1° for de>630

Large angular deflections are permitted in the case of joints specifically designed to accommodate such deflections. The manufacturer of the coupling will specify the permitted angular deflection.

Weholite Jointing

29

Installation Types and Related Consolidation Deformation

Design GraphAn intensive study of the deflection history of pipes installed under different conditions is presented in the graph.

“Well” compaction, Cf=1.0The embedment soil of a granular type is placed carefully in the haunching zone and compacted, followed by placing the soil in layers of 300mm maximum, after which each layer is compacted carefully. A layer of at least 150mm must cover the pipe. The trench is further filled with soil of any type and compacted. Typical values for the Proctor density are above 94%.

“Moderate” compaction, Cf=2.0The embedment soil of a granular type is placed in layers of 500mm maximum, after which each layer is compacted carefully. A layer of at least 150mm must cover the pipe. The trench is further filled with soil of any type and compacted. Typical values for the Proctor density are in the range of 87-94%.

“None” compaction in granular soil, Cf=3.0The embedment soil of a granular type is added without compaction. Installation of this type is NOT recommended.

“None” compaction in clay, Cf=4.0The embedment soil of a cohesive type is added without compaction. Installation of this type is NOT recommended.

Weholite Pipelaying

The average deflections immediately after installation are represented by the lower boundary of each area, and the maximum values by the upper.

Pipe deflection after installation

NOT RECOMENDED

MODERATE

WELL

12

10

8

6

4

2

0

-22 4 8 16

Ring stiffness [kN/m 2 ]

inst( /d)

Cf = Consolidation factor.

30

Validity of the Design GraphThe design graph is valid under the following conditions:

• Depth between 0.8m and 6m, both included.• Depth/diameter ratio at least above 2.0• Designers first need to establish permissible deflections, average and maximum (national requirements product standards, etc.).• Pipes fulfil the requirements listed in the Weholite internal standard and international standards.• Installation categories “well”, “moderate” and “none” reflect the workmanship on which the designer can rely.• Sheet piles are removed before compaction. If the sheet piles are removed after compaction, the “well” or “moderate” compaction level will be reduced to the “none” compaction level.• For the deflection mentioned in the graph, the strain will be far below the design limit and need not be considered in the design.

Trench WorkThe size and shape of the trench are planned on the basis of the size of the pipe or pipes to be laid as well as the soil data gained from soil investigations. The trench is generally made as narrow as possible, taking into account the width needed for possible supporting structures, working space and space needed for proper placement of the backfill soil. The minimum width of the bottom of an open trench is 0.7m and that of a supported trench 1.0m. Making a trench unnecessarily wide should be avoided, as the effect of the side support might be weakened.

When determining the trench depth, sufficient space for a bedding layer of at least 150mm must be taken into account, should the native soil be suitable as bedding. The final excavation is made carefully, so that the bottom of the trench is kept as undisturbed as possible. Moving about on a soft or easily disturbed trench bottom must be kept to a minimum.

The slope of a trench wall and the need for support are determined on the basis of appropriate needs and general workplace safety aspects. The slope inclination and need for support are specified in the national standard specification for civil engineering construction.

BeddingOn the bottom of the trench, on top of an exchange material or on top of a grating, a 150mm-300mm thick bedding layer is prepared and well compacted (>95% Proctor). The bedding may consist of sand, gravel or crushed pebbles, free from stones within the width of the pipe trench. The bedding needs to be at least 200mm wider than the pipe outside diameter to enable proper compaction work. For installations in wet or soft soil, a geotextile must be placed under the bedding in order to prevent the bedding from being washed away.

The largest permissible particle size dmax for natural stone materials to be used is determined on the outside diameter of the pipe to be installed. For DN<600, dmax = 0,1 • DN. For DN>600, dmax is always 60mm. Crushed pebble material must not be larger than 32mm and/or in accordance with national stand-ards.

If a pipeline is founded directly onto levelled native soil, the trenching work must be done carefully, avoiding unnecessary over-excavation, in order to keep the trench bottom sufficiently level. The whole bedding layer depth must be stone free.

LayingBefore starting to lay the pipe, check that the pipes and materials to be used are free from defects. Clean them carefully after transportation and any machining done before installation.

The pipes are laid on the levelled trench bottom or bedding so that the pipe is supported evenly over its full length. Excavations are made in the trench bottom or bedding for the sockets, so that the weight of the pipes do not rest on the sockets. Do not lay pipes on top of wooden planks or similar.

Weholite Pipelaying

31

During laying, the water level in the trench must be kept sufficiently low to prevent flotation or water from damaging the laid pipe. When laying work is interrupted, the ends of the pipes must be sealed to prevent ingress of dirt or water.

When laying pipes in road and railway areas, instructions from the relevant authorities must be observed.

BackfillingThe term “primary” refers to the material to be used around the pipe above the native soil trench bottom or the bedding. Primary backfill extends to at least 300mm above the pipe crown and/or as specified by local standards.

The primary backfill material must meet the same requirements as the bedding materials. Backfilling should extend over the entire trench width. The primary backfill material may not be dropped on top of the pipe in such a way that the pipe is moved or damaged; it must be placed as evenly as possible on both sides of the pipe and packed under the pipe haunches and on the sides.

In the first stage, the material is spread in the trench with a spade or by other means and compacted so that the pipe is not moved or damaged. If necessary, the pipe may be pressed down or anchored or filled with water to prevent it from lifting during compaction. The backfill material is compacted in layers of 150-300mm.

The final layer of the primary backfill must extend 300mm above the crown of the pipe; to avoid ovalisa-tion of the pipe, the soil layer on top of the pipe can only be mechanically compacted when it is at least 300mm thick.

The degree of compaction must be at least 90-95% Proctor, if not otherwise stated in the contractor’s plan.When removing supporting structures (such as sheet piles or trench boxes), take care not to endanger worksafety or trench wall stability, loosen the compacted backfill or move the pipe out of position.

The final backfill material may be compactable as-dug material, but must in any case be free from stones larger than 300mm. Where necessary, and especially in traffic areas, compaction is carried out in several 300mm layers to compaction levels corresponding to those of the primary backfill. On the surface, use backfill material that matches the surrounding surface.

Structural DesignIn general, structural design of a pipeline by analytical or numerical methods is not needed. Any calculated prediction of the pipe behaviour depends greatly on the degree of correspondence between the calculation assumptions and the actual installation; it is therefore important to base the former on reliable input values obtained from extensive soil surveys and monitoring of the installation.

However, when structural design is required, e.g. in cases where no other information exists, a method as defined in EN 1295-1 should be used. As far as input values for the pipes are required, the following values are recommended:

Weholite Pipelaying

PE10000.4

13 x 10-5

RemarksModulus of elasticity

Poisson’s ratioLin. expansion coefficient

MaterialE-modulus (MPa)

(-)(mm/mm.K)

32

Pressure Testing on Non-Pressure Pipes on SiteTestingIn the acceptance inspection, if required, compliance of the installation work with the planning documents is verified. As part of the final inspection, tightness can be tested. Tightness testing of Weholite pipes is performed with reference to national requirements, but normally according to the following alternative methods:

SABS 1200 LD 1982 Standard specification for civil engineering construction; LD sewers SFS 3113.Leak testing on pipelines is conducted either with air or water.

Principle(Summary of the Finnish standards SFS 3113)A delimited section of pipe is filled with water and subjected to a certain overpressure. The tightness is determined in the final stage of the test by determining the quantity of additional water needed to maintain the pressure.

The necessary overpressure in the pipe depends on the level of the ground water in relation to the level of the piping to be tested. The difference between these two levels is marked with “a”. The overpressure is derived from the following graph:

Methoda. Fill a pipe section with water to overpressure P. Check that all seals are watertight and hold the pressure for 10 minutes.b. The overpressure is maintained at the level P during half an hour by adding water when necessary. Measure the volume of water added during three 6-minute intervals.c. When the test is completed, the average volume of the added water is calculated. This volume is converted into functions of pipe length and time (ℓ/mh),:

ℓ = litre of added waterm = length of piping in metresh = hour

The value thus obtained and the inside diameter of the pipe are inserted in the diagram below. All readings below the line are acceptable.

For further information, see Standard SFS 3113.

33

Pressure Testing

Difference between the

subsoil water and the pipe (m)

Test overpressure Pe1

kPa Bar

10.015.521.026.532.037.548.554.059.565.5

a<00<a<5

0.5<a<1.01.0<a<1.51.5<a<2.02.0<a<2.52.5<a<3.03.0<a<3.53.5<a<4.04.5<a<5.0

0.10.1550.210.2650.320.3750.4850.5400.600.652,6

2,4

2,2

2,0

1,8

1,6

1,4

1,2

1,0

0,8

0,6

0,4

0,2

0Volu

me

of th

e ad

ded

wat

er p

er le

ngth

uni

t and

the

dura

tion

of th

e te

st

l/m h

Inside diameter mm

200 400 600 800 1 000 1 200 1 400 1 600

Testing SABS 1200 LD Sewer 1982

GeneralAll acceptance tests shall be carried out in the presence of the engineer and at such times and in such manner as the engineer may direct. Subject to the provision of 7.1.5, no pipe joint or fitting shall be covered until the applicable tests given in 7.2 have been completed and the engineer has:

a. given his written acknowledgement that the sewer or the specified section of it has passed the said test, andb. authorised such covering.

The sewer or any section of it shall be inspected by the contractor who, if he deems it ready to be tested, shall advise the engineer of his intention to subject the sewer or said section of it to the appropriate tests.

The sewer shall be tested in sections between manholes or chambers, as applicable, the section being tested must be isolated from other sections by means of suitable plugs or stoppers that have been braced adequately.

Notwithstanding any acknowledgement by the engineer in terms of 7.1.2, after backfilling and compaction have been completed, the engineer may order that the sewer be retested to check that it has not been disturbed or damaged during backfilling.

The engineer may order one of the following to be carried out on the sewer or any section of it:

a. 1. an air test on pipes (other than concrete pipes) of all sizes; or 2. in the case of pipes (other than concrete) of diameter up to 600mm, an air test followed by a water test;b. a water test in the case of pipes of diameter up to 750mm; c. a visual internal inspection in the case of pipes of diameter greater than 750mm.

The contractor shall provide all labour and apparatus (including expansive plugs and flexible bag stoppers) that may be required for carrying out the tests.

All test results shall be recorded in the manner directed, whether or not the pipeline or section of pipeline has passed the test.

34

The amount lost shall not exceed the applicable of the following rates per 100m of pipeline per hour:

Should any section of the pipeline fail to pass the water test, a retest will be permitted and, in such case, acceptance or rejection of the section shall be determined on the result of the retest.

RejectionIn the case of AC, vitrified clay and pitch-impregnated fibre pipes, failure under the air test will be deemed to be cause for rejection. After such rejection, the contractor may apply a water test to locate the source of failure, rectify the pipeline, and re-apply the air test. In the case of reinforced concrete, failure under the water test will be deemed to be cause for rejection.

Test of Connecting SewersEach connecting sewer shall be tested between its upper end and the junction at the main sewer. The upper end of the connection shall be kept securely closed with expanding plugs during the test. Where practicable, the contractor may test the main and connections simultaneously if he so wishes. On completion of the test, the upper end of the connection shall be permanently sealed as directed by means of a plug stopper suitable for the type of pipe.

Test of Rising MainsAfter a rising main has been laid and the joints completed, the main shall be slowly charged with water, so that all air is expelled, and then tested in accordance with Subclause 7.3 of SABS 1200 L.

Watertightness of ManholesWhere so required in terms of the project specification, manholes shall be tested for watertightness separately from the pipeline.

Nominal diameter of pipe (mm)

Minimum time (min) taken for pressure to drop from 2.5 kPa to

1.25 kPa100150200225250300375450600750

2.03.04.04.24.56.07.59.012.015.0

Nominal diameter of pipe (mm)

Loss rate in litres per 100m per hour max

100150200225250300375450600750

6.09.012.013.515.018.022.527.036.045.0

Tests and Acceptance/Rejection CriteriaAir TestPipelines above the water table:

An approved air testing machine shall be used to raise the gauge pressure in the section of the pipeline under test first to 3.75 kPa. After a 2 min stabilisation period, the pressure shall be reduced to 2.5 kPa. The machine shall then be switched off and the time taken for the pressure to drop from 2,5 kPa to 1.25 kPa shall be determined. The time taken shall be at least the applicable of the following values:

Pipelines below the water table:

An approved air testing machine shall be used to raise the gauge pressure in the section of the pipeline under test to 2.5 kPa above the static water pressure. After this pressure has been attained and the machine stopped, any change in pressure shall be noted. There shall be no discernible loss for a period of at least 5 min.

Water TestThe section of the pipeline under test and, unless otherwise specified, the manhole chamber at the upper end of the said section shall be filled with water to such a depth that every portion of the pipeline is subjected to a pressure of not less than 12 kPa and not more than 60 kPa.

During the test, there shall be no discernible leakage of water. An appropriate period, which shall be at least 10 min, shall be allowed for initial absorption, and the loss of water over the next 30 min shall be noted.

35

Support Spacing and Buoyancy

Support Spacing

BuoyancyWhen installing pipes under the ground water level, the buoyancy of the pipe must be taken into consideration. Where necessary, the natural uplift of the pipe should be counteracted. This can be designed case by case. Please do not hesitate to contact your nearest Marley branch for technical information.

DN/IDmm

36040050060070080010001200140015001600180020002200

dnmm

40045056067579090011251350157516801792201622402464

Pipe EmptyProfile Empty

kN/m

1.231.522.383.434.666.098.9713.7018.6521.4124.3630.8338.0646.04

Pipe FullProfile Empty

kN/m

0.240.290.450.650.891.161.272.613.554.084.645.877.258.78

Pipe FullProfile Full

N/m

101010102020304050607090110130

Support spacing

- sag 10mm/10 years- liquid density 1000kg/m3

Supp

ort s

paci

ng, m

6

5

4

3

2

1

0

200

400

600

800

1000

1200

1400

+ 20 °C

+ 40 °C

+ 60 °C

Pipe ID, mm

With installations above ground, the maximum support spacing can be determined according to the figure on the left hand side.

36

General Notes and Limitations

General NotesThis Structured Wall Pipe (Weholite) Manual has been produced as a guide for engineers, purchasing officers and contractors to cover the application and use of Weholite pipes and fittings.

This document will be reviewed from time to time in order to keep it fully relevant to modern water and wastewater industry practice. Any comments and suggestions regarding its content will be appreciated.

The information contained herein is intended as a guide, and its accuracy and applicability is not guaranteed. Marley Pipe Systems assumes no obligation or liability in respect of this information. All tables and statements may be considered as recommendations, but do not constitute a warranty. Users of our products should carry out their own tests to determine the suitability of each product for their particular purposes. Marley’s liability for defective products is limited to the replacement, without charge, of any product found to be defective in line with their standard condition of tender and sale. In no circumstances shall it be responsible for any damages beyond the price of the products, and in no event shall it be liable for consequential damages.

Limitation of LiabilityWhilst the information, opinions, advice and recommendations contained in this publication have been prepared with proper care, they are offered only in order to provide useful information to those interested in technical matters associated with pipeline design, selection and installation.

The information contained herein is not intended to be an exhaustive statement of all relevant data, as the successful installation in each case may depend on numerous factors beyond our control. Marley Pipe Systems accepts no responsibility for or in connection with the quality or standard of any pipeline or installation or its suitability for any purpose when installed.

All conditions, warranties, obligations and liabilities of any kind which are or may be implied or imposed to the contrary by any statute, rule or regulation or under common law and whether arising from the negligence of the Company, its servants or otherwise, are hereby excluded except to the extent that the Company may be prevented by any statute, rule or regulation from doing so.

37

Conversion Factors

Numerical values of SR corresponding to some standard classification series.

For GRP pipes, SR is also used for pipe classification but the unit is commonly N/m2 (Pa) according to ISO, e.g. 1000 times larger than the standard values for thermoplastics. A common series is 2500, 5000, 10000 and 20000 N/m2.

In the USA, the ring stiffness concept is also used, but is then defined according to ASTM and expressed in psi. The numerical values in psi in the above table are 8 times larger than those given above in kN/m2, e.g. 16, 32, 64, etc. A common pipe stiffness series used in the USA for GRP is 18, 36 and 72 psi.

Volume (litres, cubic feet, gallons) Volume (m3, cubic yards, gallons)

Volume (m3, acre feet, morgen feet, gallons) Flow

SR (kN/m2 = kPa)SR (MN/m2 = MPa)SR ((psi) acc. ASTM 28)Stiffness (kPa) SANS 1601PVC (D/s = SDR)PVC (ISO S-series)PVC (s/Dm%)PVC (PN bar)HDPE 63 (PN bar = s/Dm%)HDPE100 SDR

20.002

16100512524

3.233

40.004

3220041202.55426

80.008

64400331636521

160.01612880026

12.548

6.317

Gallons (lmp)219.969

6.2288168.1780.83268

1

Litre (dm3)1

28.31683.785424.54609

Cubic Metres1

0.764550.003785

0.00454609

Cubic Yards1.30795

10.004951150.0059461

Cubic Feet0.0353147

10.1336820.160544

Gallons (US)0.2641717.480456

11.20094

Gallons (lmp)0.2199696.22880.83268

1

320.032256160021105108

13.6

Gallons (US)264.171201,974

11.20094

Gal (lmp/min)13.1981413198.14373.73

1

m3 (kilolitre)1

1233.482610.71

0.00454609

Litre/second1

100028.3168

0.0757682

m3 /second0.001

10.0283168

75.7682 x 106

Acre Feet0.00081071

12.11654

0.000003686

Morgen Feet0.000383038

0.472471

0.0000017413

Gallons (lmp)219.969271328574275

1

ft3/second0.035314735.3147

10.002676

38

Conversion Factors

Force

Pressure

0.1019721

10000.453592907.1841016.05

0.101972 x 103

103

10.453592 x 103

0.9071841.01605

0.2748092.204622204.62

120002240

0.112405 x 105

1.10231 x 103

1.10231 x 103

0.00051

1.120

0.10036 x 103

0.984206 x 103

0.9842960.446429 x 103

0.8928581

19.806659806.654.448228896.449964.02

NewtonKilogram -

ForceMetric Ton

- ForcePound - Force

Ton (2000lb Force)

Ton (2240 lb) Force

Pascal (Newton/m2)

Bar Kilogram Force/cm2

Pound Force per inch2

Metre head of water

Foot head of water

Ton (2000lb) force/in2

Ton (2240lb)force/in2

1105

98.0665 x 103

6894.769.80665 x 103

2.98898 x 103

13.7895 x 106

15.4443 x 106

10-5

10.9806650.06894760.09806650.0298898137.895154.433

0.101972 x 10-4

1.019721

0.0703070.1

0.03048140.614157.488

0.145038 x 10-3

14.503814.2233

11.422330.433515

20002240

0.101972 x 10-3

10.197210

0.703071

0.30481.40614 x 103

1.57488 x 103

0.072519 x 10-6

0.00725197.11167 x 10-3

0.00050.711167 x 10-3

0.21676 x 10-3

11.120

0.33455 x 10-5

33.45532.80842.3067273.28084

14.61332 x 103

5.16692 x 103

0.064749 x 10-6

0.0064796.34971 x 10-3

0.446429 x 10-3

0.634971 x 10-3

0.193533 x 10-3

0.8928581

39

Notes:

40

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