PEWATER PIPE AND FITTINGS ENGINEERINGTECHNIQUEMANUAL

LESSO

ABOUT LESSO GROUP

Establishedin986LESSO(StockCode:28.K)isagobaladerinomefumishingsandbildingmaterials.eGroup’sbsine portfoliosastedtao andothersItersiengefprouctsschspeotoolasumbgditaryareitegraliateseal dorsandidokdartosaterrifateroiteraldantsfietit valvesablsotai LESSO’s sales revenue reached over USD 4.38 billion.

Sinceimplementingastrategofglobaizationandexpandingitsgobalpresence,LSSOsevoledintoasophisticatedutiatiallt boastsmoretadaedoductisodidodengiusrandosrsiarthcao AmericaEuroricaabdituctdcfosdi its continuously improved strategic layout in a timely and efficient way.

LESSOhasfonddits&teritrea0tifsearrsatileidteiseetdt post-doctoralorkstatiostospportitsinovaioandtechicaldevelopmentTeGroupastakenaleadingolentheevisioofoer internationalandChineseindustrystandards.LESSOownsover30patents(someofthemarepending)，andprovidesor.000 varetiesofproductsmakingitoneofthemostcomprehensivemanufacturersinthepingindustryItsproductsareutizdglobalyin difrentareasincuingomedecorationcivionstructionmunicipalwatersuplydrainageergymanagement,owerplyd telecommunications,gas supply,fire-fighting,environmentalprotection,agricuture,oceanicaquaculture,etc.

Truetoitsideaof“EvisiongteettruilngteFuture”ESOmainsommittedtoeatingbttelivngeviotad advocatinltdisifl insustaining healthyand beautiful space so that global residents could enjoya comfortable life.

CohesionandDrivers for Progress

JOINHANDS,FORGEAHEAD

ChinaLessoGroupHoldingsLimited(StockName:ChinaLeso,StockCode:0228.HK)isalargeindustrialgroupofhomefurishings andbuildingmaterialsinChina.ChinaLesso’sbusinessportfoliospansplasticpipingbuildingmaterialsandhomefurnishings, environmental protection,new energy,supply-chainservice platformsand others.

Contents

PEWATERPIPEANDFITTINGS ENGINEERINGTECHNIQUEMANUAL

I. Overview of PEWater Pipes

1.DevelopmentofPEWaterPipes.. 02
2.TypesofPEWater Pipes 02
3.CharacteristicsofPEWaterPipes 03

II.LESSO PE Water Pipes

1.Materials 04-08
2.Applications 09
3.Pipe Connections 09-18

Ill. Outdoor Underground Water Supply System

1.Transportation and Storage of
Pipesand Fittings 19
2. Piping System Design... 19-21
3.Piping Construction 22-24
4.Hydrostatic Testing and Flushing 25

IV.Water Supply System for Buildings

1.Material Transportation and Storage 26
2. Design. 26-29
3.Constructio... …29-31
4.Quality Acceptance 32

LESSO

Preface

Polyethylnectct fitib asingleunitsectitsurefelbdosfctitotrtintoespadsefn constructionproctsepromotioofeslgsithedelinsoftCina’sinsrfstructiodtStateEcooicdTrade Commission fordeveloping chemicalbuilding materials,andmeets growingdemandsdriven byrising living standards.

ThespecifiainsdmesiosandpeformaneofLESSOwateresomplyithteuirementsofyetyene(E)Pipingstesfor WaterSuplartBdeittf Polyethylene(PE)PpingstsforWaterSuplyart:itinsB66)ESOatepsnfitingsreasoafactured inaordanceihtherequirementsofGB719andtheygienicsafetyevaluationregulaiossetbyChina’sNatioalHalthommssio

LESSOPEpipesaremadefromimportedpolyethylene.TherawmaterialsofwaterpipesareimportedPE10OorPE80polyethylene.

Thismautsctaee watersupplysystems inresidentialareasand factories,aswellas industrialand water treatmentpipingsystems.

Thismanualwasprepaditeferencetourrenthcalregatiosandsuggestiosfromexertsitdomestcwatersupplydrainage industryhisasmotldatioprtaterialfradctssioctid acceptanceofpolyethylenewatersupplysystemscomplywithrelevantnationalandlocalstandards,specificationsandruatios.

LESSO

I.Overview of PE Water Pipes

1.DevelopmentofPE WaterPipes

PEwaterpipeshavebecometheworld’ssecondmostconsumedplasticpipingvarietyafterPVC-Upipes.Theyarewidelyusedingas trasisiolist PEpipes werefirstusedinthe1940s.Thefirst-generationofPEpipe-graderesins-suchas PE32,PE40andPE63-hadlow comonomercontentPEpipesextrudedfromtheseresinsexhibitedbritleflureduringlongtermhydrostaticstrengthtests.Thesecond generatinresinslasifiedasE8eredeveloededonthefisteeratiobycresingthomoomerotentTisdiiatio significantlyimprovedenvironmentalstresscrackresistance (ESCR)ofPEpipe-graderesins.Inadion,thethird-generationresins, clasifiedas PE10o,offred increased density and stifness,as wellas improved creep resistance at 2 0 ^ { \circ } { C } for 50 years,while maintaining goodESCRperformance.PE80andPE100medium-orhigh-densitypolyethylenepipesarecommonlyusedforgas transmsionThese pipesarealsousedforwatersupplysystems,whilePE63hasgradualyeenphasedout.Low-densitypolyethylenegradessuchasPE32 and PE40 are usually used for irrigation.

Long-term Hydrostatic Strength Comparisonof PE63,PE80 and PE100

2.Types ofPE WaterPipes

PE pipes are usuall clasified based on the characteristics of polyethylene materials teyare made from.

2.1Classificationbyresindensity:PEpipesarecategoredintolow-densitypolyethylene(LDPE)pipesmedium-densitypolyethylene (MDPE) pipes,and high-density polyethylene (HDPE) pipes.

2.2Classificationbylong-termhydrostatictrengthofmaterials:Basedonthelowercofidencelimitofpolyetylenepipes’predictedlong termhydrostaticstrength,theInternationalOrganizationforStandardization(SO)classfiespipesandtheirrawmaterialsintofive grades-PE32,PE40,PE63,PE80,andPE100.ThephysicalandmechanicalbasisforclasifyingPEgradescorrespondstoth hydrostatic strength (MPa) determined under specific conditions - 9 7 . 5 % lowerconfidence limit prediction,service life of50 years,and water temperature of 2 0 ^ { \circ } { C } , The material grade number is derived by multiplying the minimum required strength (MRS)by 10.For instance,PE80 hasan MRS of 8 . 0 { \mathsf { M P a } } , （204号

LESSO

3. Characteristics of PE Water Pipes

PEpipesefectivelyaddress twomajorchallngesoftraditionalpipescorosionandjointleakage.ThemainadvantagesofEpipesare as follows:

3.1PE pipes have excellent corrosion resistance.
3.2Thefusedjointsareleak-proof.PEpipesareprimarilyonectedthroughheatfusionweldingtoensurethethematerialandstructura uniformity between the joint and the pipe,achieving seamless integration of the joint with the pipe.
3.3The flexibilityof PEpiping systems provides significant technicaland economic value.Detailsare as follows:
3.3.1TheflexibityofpolyethleneenablesPEpipestobesuppliedincoilswithlongerlngths,thusminimizingthenumberofjintsand fitingsrequired,andsignificantlyreducingtheworkloadassociatedwithconnections.OurcompanysuppliesPEpipeswithdn <=slant 6 3 in coils based on practical considerations.
3.3.2PEpipeswithlargediameterscanbepre-assembledontheground(i.，outsidethetrench)beforebeinglaidintothetrench, reducing the difficulty of installationand workload.

3.3.3 In certain situations where pipes cross beneath roads,railway embankments,or rivers,PE pipesare laid byadoptingdirectional drilling technology without excavating trenches during the construction due to their flexibility, lightweight,and excellent scratch resistance

3.3.4 PE pipes can be laid at the bottom of rivers and lakes through the long-pipe sinking method. During construction, the pipe is preassembled into a continuous long one at the installation site,and lowered intopositionby fixingweightsdirectlyto sinkthemto the bottom.

3.3.5PE pipescan beusedas liners to rehabilitate old and damaged pipesin cities.

3.4Efectiveresistancetoundergroundmovementandendloads:PEpipesarehighlyductilewithanelongationatbreakexceeding 3 5 0 % which enables strong adaptability to uneven settlement of pipe foundations.
3.5PE pipes exhibit good resistance to rapid crack propagation.
3.6Longservicelife:PEpressurepipingsystemshaveasafeservicelifeofover50yearshichisertifiedbyinterationalstandardsand advanced foreignspecifications.
3.7EasytocllyetomtalldatelatasdEfieatedit produce substances that harm the environment.

LESSO

II. PE Water Pipes

1.Materials

1.1Alofourpipereupditinspectioertfiatefalityotroeparentlogitertiatiootso health authorities and other regulatory bodies.
1.2OurPEpipesaremanufacturedusingimportedPE10OorPE80asrawmaterials,ofering higherpressureresistanceandgood resistance to rapid crack propagation.
1.3PEwaterpipeswithanoutsidediameterlessthan110mmarebue,whilethosewithanoutsidediameterofmmormoreareeither blueor blackwith blue stripes.Thestandard lengths ofpipesare6mor8m.Pipes withanoutsidediameterlssthan63mmcan be supplied in coils,orcustomized based on user requirements.
1.4OurPppesreavlbleinsionalpressureratings:MPa,PaPa1Pa,PaandPa(foe80). Fitings includeijectionmoldedsocketfiings,jectionmoldedbuttfusionfiings,electrofusionfitings,andweledfitings.
1.5ThehygieneperformanceofPEpipesandfitingscomplieswiththerequirementsofteStandardforSafetyEvaluatioofEquipmentand Protective MaterialsinDrinkingWaterSystem(GB/17219-199）andtherelevanthealthandsafetyevaluationregulationsbythe National Health Commission.
1.6 Pipes and Fittings

PEwaterpipfitinedinfouprouctlinesiectiomodedscketfitisctiooeduttfusiofiinsousi fittings,and welded fittings.

Pipe Series

LESSO

Fitting Series

Injectionmoldedsocketfittings:Theftingsare bluefordn20todn90,andblueorblackfordn110andabove. <br>Injectionmoldedbuttfusionfittings:Thefitigsarebluefordn20todn90,andblueorblackfordn110andabove.

7 PbIrr 10 000 Cross 90°Tee 90°Reducing 22.5° 45°Elbow 90°Elbow Reducer Cap (Soc) Stub Flange Plate Spacer Rubber (SocxSoc) Tee Elbow (SocxSoc) (SocxSoc) (SocxSoc) (SocxFlange) Flange Flange Gasket (SocxSoc)

LESSO

Electrofusion fittings (EF): (The fitings are black)

114
90°Welded 45Welded Welded Welded Welded Welded Reducing 11.25° 22.5° 30° 60°
Elbow Elbow Tee Cross Reducing Tee Tee Assembly Welded Welded Welded Welded Elbow Elbow Elbow Elbow

Welded fittings (The weldedfitings are blue or black with blue stripes.) <br>Tools

LESSO

1.7TheperformanceindicatorsofpipesmeettherequirementsofPolyethylene (PE)PipingSystemsforWaterSupply-Part2:Pipes (GB/T13663.2-2018).Their physical and mechanical properties are shown in the following table:

1.8Thenominaloutsidediameter (dn),nominalwalltickness(en)andnominalpresureofE80andPE0pipesforwater supplyareas follows:

Notes:

LESSO

2、Applications

PE water pipes are widely used in municipal water supply,water supply forbuildings,rehabilitationof old pipes,aswell as industrial and water treatment, but are not suitable for indoor fire-fighting pipes.

Pipe Connections

1.The main connection methods of pipes are:

(1).Socket fusion jointing or electrofusion jointing is used when pipes with dn <=slant 6 3 \mathsf {mm } (2).Butt fusion jointing or electrofusion jointing is used when pipes with di \AA >= 7 5mm (3).For connections with metal pipesand pipeaccessories,flange jointing or transition fiting jointing can beused.

2.Socket Fusion Jointing

A socket fusion welding machine is used with the following steps:

a. Check the quality of the pipe,and ensure the connectionarea iscleanandundamagedwith the cut end flat and smooth without burrs. b.Measureand mark thedepth of the socket on the surface of the pipe.

c. Usea specialized scraper to treat the connection surface of the pipe,ensuring a fresh layer exposed around the surface.The joint should be chamfered at a 3 0 ^ { \circ } bevel angle, with the surface bevelling lengthnotexceeding 2 . 0 { \mathsf {mm } }

d.Wipe thesocketof the fitingwitha dry cloth to clean it.

e. Insert the pipe and fitting into the heater simultaneously without rotating to heat the joints.

f. Pull out the pipe and fiting after heating for the prescribed time,and quickly,steadily,and uniformly push the pipe into the socket of the fitting to forma beaded ring around the socket.

g.Allow the pipe and fitting to cool for the specified time before proceeding to the next operation.

LESSO

3. Butt Fusion Jointing

3.1Abutt fusionwelding machine is used with the following steps:

a.Prepare the necessary tools.

b. Secure the pipes to be connected in the weldingmachine'sclampsandclamp them tightly. Clean the connecting ends of the pipes,and mill them. Align the two connecting pipes to ensure the misalignment does not exceed 10 % of the wall thickness.

c.Place the heating plate.

d. Remove the heating plate after heating, join the two heated parts swiftly,increase pressure until the specified welding pressure is reached,and maintain the pressure until the joint has cooled.

e.Butt fusion is completed.

LESSO

3.2.Operatorsmustfollwtheoperatinginstructionsofthebutfusionweldingmachineandtherecommendedweldingparametersas showninthefollowingtable:

A1Welding Process Parameters

Key Process Parameters for Butt Fusion Welding

1.1Welding Temperature The recommended welding temperature is 2 0 0 ^ { \circ } \mathsf { C } to 2 3 5 ^ { \circ } { C } (see Tables A-1 and A-2). Pipecomponentmanufacturersorpipeinstalerscanadjusttheweldingtemperatureappropriatelybasedonthespecificworking conditions and materials.

1.2Welding Pressure and Time

1.2.1 The relationship between welding pressure and time is shown in Figure A-1.

Figure A-1 ButtFusion Welding Process

Figure: P _ { 1 } Total welding pressure { \mathsf { M P a } } P _ { 2 } Specified welding pressure,MPa; P t Drag pressure,MPa;

t _ { 1 } -Time for the weld beadto reach the specified height,s;
t _ { 2 } -Heatabsorptiontimerequiredforwelding ( = 5 x 1 0 ) ,S;
t _ { 3 } Specified transition time,s;
t _ { 4 } 一 Specified time for adjusting pressure to P _ { 1 } ,s;
t _ { s } 一 Coolingtime,min.

1.2.2 Welding pressure P _ { 1 } and specified welding pressure P _ { 2 }

Where: \boldsymbol { A } _ { 1 } -Cross-sectional area of pipe， mm ^ { 2 } = A _ { 1 } \ = _ { \Pi } x \mathsf { S } x ( \mathsf { D } \mathsf { N } - \mathsf { S } ) \ b { A } _ { 2 } 1 Ffective area of the piston in the welding machine's hydraulic cylinder, m { \mathsf { m } } ^ { 2 } = provided by the welding machine manufacturer; p _ { \ L ^ { 0 } } 1 一Force applied per unit area on the pipe， 0 . 1 5 N / \mathsf {mm } ^ { 2 } P t — Drag pressure，MPa。

1.2.3The recommended relationship between heat absorption time and nominal wallthickness is t _ { 2 } = \mathsf { S } x 1 0 Appropriateadjustments should be made when environmental conditions such as temperature and wind speed are severe.

1.3Recommended Welding Process Parameters for Butt Fusion Welding Recommended welding process parameters are shown in Tables A-1 and A-2.

LESSO

A1.2 Key Process Parameters for Electrofusion Socket Welding and Electrofusion Saddle Welding

Thekey process parametersforelectrofusion socketweldingand electrofusionsaddle welding include voltage,heating time, cooling time,andresistancevalue.Thekeyprocessparametersforelectrofusionsocket weldingand electrofusionsaddle weldingare provided bypipe componentmanufacturers.

LESSO

A2 Inspection and Testing Requirements for Welding Process A2.1 Inspection and Testing for Butt Fusion Welding Process

Meet the standard requirements in TSG D2002-2006 as shown in Table A-3.

A2.2 Inspection and Testing for Electrofusion Socket Welding Process

LESSO

A2.3 Inspection and Testing for Electrofusion Saddle Welding Process

Requirements are shown in Table A-5.

A3 Quantity of Test Pieces for Welding Process and Qualification Requirements

Twosetsoftestpiecesarerequiredforweldingprocessqualification.Theweldingprocessisdeemedunqualfiedifbothsetsoftest pieces failed the visual inspection;
The welding process is also unqualified if any other inspection items failed.

A4ReferenceStandards

(1）Polyethylene(PE)Pipeand Fitings-Determinationofthe Tensile StrengthandFailure Modeof TestPieces froma Butt-fused Joint (GB/T19810-2005)
(2）Thermoplastics Pipes for the Conveyanceof Fluids-Resistance to Internal Pressure-Test Method(GB/T6111-2003)
(3）Plastics PipesandFitings-CrushingDecohesionTestforPolyethylene(PE)Electrofusion Assemblies (GB/T19806-2005)
(4）PlasticsPipesanditings-PeeDecohesionTestforPolyethylene(PE)ElectrofusionAssembliesofNominalOutsideDiameteGreater Than or Equal to 90mm (GB/T19808-2005)

Appendix B

Polyethylene Welding Process Qualification Report

I. Polyethylene Welding Process Qualification Report- Butt Fusion Jointing

Organization Being Assessed:

Reported by: Reviewed by: Approved by: Report Date: Attachment: Original Report from the Inspection and Testing Organization

LESSO

3.4、Electrofusion Jointing

Electrofusionkettingisactedieseeddaealtefeee.Itseifor smal-dameterpipesandapplicationswhereconstructionischalenging.Anelectrofusionjointingdiagramisshownbelow:

Note:

While connecting,the heating voltage and time must be based on the instructions of electrofusion welding machine manufacturers.The joints must not be moved, or applied with external force during the cooling period of the electrofusion jointing.

4.Electrofusion Jointing

ElectrofusionkettinisactedieeddelintefeeeIsetifor small-diameterpipesandapplications whereconstructionischalenging.Anelectrofusionjointingdiagramisshownbelow:

a. Clean any dirt from the pipe surface to beconnected,and markthe insertion depth.

d. Connect the power supply to perform electrofusionwelding,and a small amount of molten material shall spill from the observation hole

b.Scrape off the surface layer to a thickness of 0 . 1 \mathsf {mm } to 0 . 2 \mathsf {mm }

e.Electrofusion jointing is completeafter cooling.

c.Slide the electrofusion fitting onto the pipe, and straighten the pipe to ensure it is aligned.

Note:

While connecting,the heating voltage and time must be based on the instructions of electrofusionweldingmachine manufacturers.The jointsmustnotbe moved,or applied with external force during the cooling period.

5.Transition Jointing

Transition fittings like threaded or flanged adaptersareusedforconnectionswithmetal pipesor pipeaccessories suchasvalvesand watermeters.

Flange TransitionJointing Diagram

LESSO

Use of Butt Fusion Jointing at Sites

LESSO

Trenchless Technology

Servicessuchtesalidpetfodiaaai

Horizontal Directional Drilling Technology

Instalaiontcsieililinmbngndpelnaoucdtsptdia

LESSO

IlI. Outdoor Underground Water Supply System

1、Transportation and Storage of Pipes and Fittings

1.1The transportation of underground plastic water pipes and fitings should meet the following requirements:

.1.1Pipessouldbddiarendsuldotbtowopd,oledoagdNometalicopsorapsldbe employed for lifting when mechanical equipment is used.

1.1.2Pipessoealuredietalosriaspoatiodoecti shouldbetakentopreventdeformationofpipeends.Thestackingareasshouldbefreeofsharpobjects thatmaydamagethepipes and protected from direct sunlightand high temperatures.

I.1.3Fitings should bestacked neatlyin layers,secured firmlyand protected from rain during transportation.

1.2The storage of underground plastic water pipes and fitings must meet the following requirements:

1.2.1Pipesandfitingssouldbestoredinwellentilatedwareouseorsedandeptawayfromatsoures.Pipesstoredutdorsmus be protected from direct sunlight.

1.2.2Pipesandfitingsshouldnotbestoredithilsorhemialsandstorageareasshalbeequippedwithfirepreventionasures.

1.2.3Pipesshouldbackedorzontalyonflatsupportsortheground,ndtheppeendssouldbeprotectedfromefotionwith protectivemeasuresimplemented.Straightpipesstackedinatrapezoidalorrectangularmannerwithsideprotectivesupportsshouldnot haveastackingheightexceding1.5m.Forstraightpipesstoredonlayeredshelves,theheightofeachshelfshouldnotexceedmand thetotalstacking heightshouldnotexceed 3m.

1.2.4Fitingssoudbstoredinoxesoelvestackedoaflatgroundestackingghtshouldtexcedmfire stored in boxes.

1.2.5Pipsdtels shouldbefollowed.

1.3Undergroundplasticwaterpipesandfitingsshouldnotbestoredforalongtime.Thestoragetimeofpipesfromproductiontouse shouldnoteceed18montsand24monthsforfitings.Ifteaboeduratioisxceeded,thepysicalandmechanicalpropertiesof pipesandfitings shouldbere-sampledand tested,andallpipesandfitingscanonlybe usedafterpassing the test.

2、Piping System Design

2.1 General Regulations

2.1.1Thedesignofundergroundplasticwatersupplypipingsystemshallotonlyomplywiththeregulationsofthischapteutalso conformto therelevantregulationsof thecurentnational standards:Codefor Designof OutdoorWater Supply Engineering (GB50013),and Structural Design Code for Pipelinesof Water Supplyand Waste Water Engineering (GB50332).

nal force analysis should be conducted for pipes based on pipe-soil interaction.

.1.3Theservicelifeof pipesshouldnotbe less than5Oyears,andthestructuralsafetyshallnotbelowerthan Grade l.

2.1.4Rigidbedingfoundationsmustnotbeusedforpipes.Forplasticwaterpipeswithconcreteprotectiveencasementstructures,the concreteprotectivestructureshallbedesignedto bearallexternal loads.

.1.5Theinteralwaterpressureofthepipingsystemmustnotexeedthepipe’smaximumoperatingpressure.Temaimumoperating pressure should be calculated using the following equation:

MOP = PN · f.

Where: MOP- -Maximum operating pressureof pipe (MPa); PN Nominal pressure of pipeline (MPa); \boldsymbol { f } _ { t } （204 -Pressure reduction factor for temperature of pipe.

The pressure reduction factor (ft)for temperature of PE pipes can be calculated based on the table.

2.1.6Thedesignedstandard internal waterpressureofPEpipesundernormalworkingconditionsshouldbecalculatedbasedthe following equation:

Where: Fwd·k 一Designed standard internal water pressure of pipe (MPa); F _ { w k } 一Standard operating pressureof pipe (MPa).

LESSO

2.1.7WhenfabricatedfitingsweldedfromPEppesareusedinPEwatersupplypingsystems,tefolowingrequirementsmustbemet:
2.1.7.1 Welded fitings must be pre-assembled in the factory.
2.1.7.2 The cutting angle for each pipe segment of welded elbow must not be greater than 1 5 ^ { \circ } .If the cutting angle is less than or equal to 7 . 5 ^ { \circ } the pressure reduction factor of fittings should be 1.0.If the cuting angle is greater than 7 . 5 ^ { \circ } ,the pressure reduction factor of fitings should be 0.8.
2.1.7.3The pressure reduction factor of welded tees should be 0.5.
2.1.8The pipes must include water hammer mitigation measures.

2.2 Piping Layout and Installation

2.2.1Pipes must not pass through building foundations.
2.2.2Pipes should not pass through rainwater and sanitary manholes or drainage systems.
2.2.3Anti-freezing measures must be taken in areas where freezing may occur.
2.2.4The minimum cover depth for underground pipes should comply with the folowing requirements:
2.2.5.1 The cover depth should not be less than 1.Om for pipes laid under motorized roads.
2.2.5.2The cover depth should not be less than O.6m for pipes laid under non-motorized roads and sidewalks.
2.2.6Pipessouldlaiderticalyifteyosseneathggraderodxpresayslayandmajormuicipalpipelinili Andthesepipesshould beprotected byusing reinforcedconcrete pipes,steelpipesorductileionpipesasprotectivesleeves. The inside diameter of the sleeve must not be less than the outside diameter of the encased pipe plus 2 0 0 \mathsf {mm } and coordination with relevant authorities should be carried out.

2.3Pipe Hydraulic Calculation

:.3.1The total head loss of pipe can be calculated using the following equation

Where: h _ { { z } } — Total head loss of pipe (m); h _ { { y } } 一 Frictional head loss of pipe (m); （20 h _ { j } — Minor head loss of pipe (m).

2.3.2The frictional head loss of pipe can be calculated using the following equation:

Where:λ Darcy friction factor of pipe; L （20 Pipe length ( \mathsf { m } ) 15 （20 d _ { i } （204号 Inside diameter of pipe ( \mathsf { m } ) V Average flow velocity in pipe ( \mathsf { m } / \mathsf { s } ) g （204号 Gravitational acceleration ( \mathsf { m } / \mathsf { s } ^ { 2 } ) can be taken as 9 . 8 1 { m } / { s } ^ { 2 } \Delta （204号 Equivalent roughness of pipe ( \mathsf { m } ) can be taken as 0 . 0 1 0 x 1 0 ^ { - 3 } m to 0 . 0 1 3 x 1 0 ^ { - 3 } { \sf m } ; Re Reynolds number; 7 Kinematic viscosity of water ( \mathsf { m } ^ { 2 } / \mathsf { s } ) T Water temperature ( ^ { \circ } \mathsf { C } )

2.3.3 The minor head loss of pipe can be calculated using the following equation:

Where:— Local resistance coefficient of pipe.

Ifthereisinsuffcientdataforcalculation,theminorheadlossofmunicipal watersuppypipingnetworkscanbecalculatedas 8 % to 12 % ofthefrictional head loss.Theminor head lossofwatersupplypiping networksinresidentialareascan becalculatedas 12 % to 1 8 % of the friction head loss.

LESSO

2.4 Structural Design of Pipes

2.4.1Theclassfiatiofadctiosaracterisicusofctioepresentativeluenduaspemanenuets thepipeshallalcomplywithterelevantregulationsofthecurrntnationalstandard:StructualDsignCodeforpelinesofWater Supplyand Waste Water Engineering (GB50332).

2.4.2Theartificialarcshapedsoilbeddingforapipeshouldbepavedwithmediumtocoarsesand.Thethicknessofthetificialarc shaped soil bedding below the pipe bottom can be calculated using the following equation:

hd≥0.1(1+d)

Where: h _ { d } ——Thickness of artificial arc shaped soil bedding ( \mathsf { m } ) belowpipe bottom should not be less than 1 5 0 \mathsf {mm } 1 d,Nominal diameter of pipe (m).

2.4.3The dimensions of the artificialarc shaped soil beddingabove the pipe bottm shallbe determined byadding 3 0 ^ { \circ } to the support angle valuecalculatedfromtheengineeringstructure.Thesupportangleoftheartificalarcsapedsoilbeddingshouldnotbelessthan 9 0 ^ { \circ }
2.4.4Thebackfilompactioncoeficientaroundthepipeshouldbeclearlyspecfiedinterelevantdesigndocuments.Thecompaction coeficientoftheartficialarcshapedsoilbeddingbeneaththepipebottomshouldbecontrolledbetweenO.85andO.90.Thebackfl compactioncoeffcientofteartificalarcshapedsoilbeddingabovethepipebottomandthebackfilnginthehaunchingreason both sides of the pipe should not be less than 0.95.

2.4.5Calculationsoflngitudinaltmperaturedeformatioofpipeareotequredifteflexiblegsketringpusonconnectionisusedin undergroundplasticwatersupplypipingsystems.Fortherconnectionmethds,longitudinalemperaturedeformationofpipesould becalculated.Longitudinaldeformationofthepipecausedbytemperaturediferencescanbecalculatedusingthefolowingequation：

△L=Cp-L·△t

Where:△L- 一Longitudinal deformation caused by temperature differences ( \mathsf { m } ) { C } _ { { p } } （2 -Coefficient of linear expansion of pipe ( \mathsf { m } / ( \mathsf { m } * \mathsf { \bar { c } } ) ) L Pipe length (m); △t- Maximum temperature difference between installation and use of pipe wall { \mathfrak { ( C ) } }

2.5Pipe Accessoriesand Thrust Blocks

2.5.1Whenflexibleconnectionsareusedinpipingsystems,theaialtustofthepipesouldbecalculatedbasedonthedesignednteal waterpressureofttatiohotaltngsiiamerseosssd Thrustblocksmustbeinstalediftheaxialthrustisgreaterthantheresistancefromthebearingstrengthoftheexteralsoilandthe frictional resistance of the surrounding soil along the pipe length.

2.5.2The thrust of pipe shallbe calculated based on the following requirements: 1）The thrust PTat pipe ends and equal tees can be calculated using the following equation:

Where: \boldsymbol { P } _ { \ u { r } } —Thrust generated by underground plastic water pipes on the thrust blocks (N); d- Nominal diameterof pipe ( \mathsf { m } ) =

2）The thrust \mathsf { P } _ { \intercal } at the horizontal elbow of pipe (Figure 2.5.2-1) can be calculated using the following equation:

3）The thrust \mathsf { P } _ { \intercal } at the horizontal tee of pipe (Figure 2.5.2-2) can be calculated using the following equation:

P=1.57-dFwdk'sin(α/2)

I 2 P EEU1 0.785dF

Thrust at Horizontal Elbow of Pipe (2.5.2-1) <br>Thrust at Horizontal Tee of Pipe (2.5.2-2)

LESSO

3、Piping Construction

3.1 General Requirements

3.1.1Theconstructionofundergroundplasticwatersupplypipingsystemengineringshallnotolyomplywiththeregulationsofthis chapter,butalsoofortoteelevantregulationsofteurrtatioalstandard:CodforConstructionndAcceptanceofWater and Sewerage Pipeline Works (GB50268).
3.1.2PipesmustbelaidongthetrenchalgnmentateedgeoftetrenchpriortoconnectionWhensocketconnectionsareused,te insertion direction should be consistent with the water flow direction.
3.1.3 Whenpipeconstructionisconductedinareaswithhighgroundwaterlevelsorduringrainyseasons,measuresmustbetakentolower waterlevelsanddrainawaywaterandwateraccumulatedinthetrenchmustbedrainedinatimelymanner.Backfilngshouldnotbe done when pipesare in a floating state.

3.2Trench Excavation and Foundation Treatment

3.2.1 Beforetrench excavation,the temporarybenchmarks,pipeaxiscontrolpiles,and elevationpilesshouldberechecked.
3.2.2 Thetypeof trenchshouldbedeterminedbasedonsiteconditions,trenchdepthgroundwaterlevels,soilconditions,construction equipment,andseasonal factors.
3.2.3 The soil pile lateral to the trench should not be less than 1 . 0 \mathsf { m } from the edge of the trench,and should not be piled higher than 1.5m.
3.2.4 Theexcavationwidthofthetrenchbotommustmeetthedesignspecifications.Ifnospecificwidth isgiven,itcanbecalcuatedusin the following equation:

1）Connection at trench bottom: Single pipe laying:

B=D,+2(b,+b)

Where:B Excavation width of trench bottom for pipe (mm); D _ { \iota } 一 一Outside diameter of pipe (mm); b _ { \scriptscriptstyle { I } } 1 一Working width on one side of the pipe (mm) can be taken as （20 2 0 0 \mathsf {mm } to 3 0 0 \mathsf {mm } .Ifa drainage ditch is requiredat the trench bottom,b1 must be increased accordingly. b _ { z } 一 -Thickness of the support on one side of the pipe can be taken as 1 5 0 \mathsf {mm } to 2 0 0 \mathsf {mm } when support is required.

2）Double pipes laid in the same trench:

Where:S — Designed clear distance between the two pipes (mm).

3.2.5Theexcavationofthetrenchmustbeotrldtopreventinterferenceoftheoilfoundation.eOomm-3oommofslabovete designedelevationshallbemanualyremovedbeforepipelaying.Sharpobjectsatthetrenchbottommustberemovedandbackfilec with sand and gravel.
3.2.6Anaturalsoilfundationisideal.Whenthenaturalfoundation’sbearingcapacitycannotmeetrequirementsorintheeventof unfavorable geological conditions,the foundation must be reinforced based on the design specifications.
3.2.7Soil foundation treatment must meet the following requirements:
3.2.7.1Forgeneralsoil,amediumtocoarsesandbeddingwithathicknessofatleast15ommshouldbelidontheundisturbedsoil foundation under the pipe.
3.2.7.2Forsoftsoilfundations,henthebearingcapacityoftefoundationfailstomeethedesignspecifications,orentebearing capacityofthefoundatioisompromisdutewateringerecavatiotereasonstatecttedisturdilt foundationmustbereinforcedbasedonthedesignspecifications.Once thespecifiedbearingcapacityisachieved,amediumto coarse sand beddingwith a thickness of at least 150mmshould be laid.
3.2.7.3If thetrenchbottomisfiledwithrocksorhardobjects,thethicknessofthemediumtocoarsesandbeddingshouldbeat least 1 5 0 \mathsf {mm }
3.2.7.4Atsitesitigroundwaterevendfuditytegeotextlesaleinstaledongtetrenchotomandsidoefor protectionwhenthepotentialossoffinegrainedsoilparticlesaroundthepipeoccurs.Temassperunitareaoftegeotextlesould preferably not be less than 2 5 0 { { g } } / { { m } } ^ { 2 }
3.2.7.5Ifthefoundationstfessdiferssignificantlyeplacementthebeddingoothermeasuresshouldbeusedtopreventuevenlaing of plasticwaterpipes.Thethicknessof thebeddngshouldbedeterminedbasedonsiteconditions,butmustbeatleast300mm.
3.2.8Whenminorover-excavationofthetrenchbottomordisturbanceof thebaseocurs,thefoundationtreatmentmustmetthe following requirements:
3.2.8.1 If the over-excavation depth is less than 1 5 0 \mathsf {mm } ,the excavated undisturbed soil can be used for backfiling and compaction. The compaction coefficient must meet or exceed the natural soil foundation’s density.
3.2.8.2Ifthesoilathetrenchbottomistoowetforcompactionnaturallygradedsandandgavelorushedstoneswithamaium particle size of less than 4 0 m { m } should be used forleveling and compaction.

LESSO

3.3Pipe Connections
3.3.1ConnectionsinpipingsystemsshalbeconductedbyusingspecificconnectiontolsbasedonthetypeofconectionThreaded connections should not be used. Open flame heating is also not allowed during the connection process.
3.3.2Specificpipecuttrsorpipecuting toolsshouldbeusedforpipeendsduringconnection.Thecutendshouldbeflatandperpe ndicular to the pipeaxis.
3.3.3The ideal ambient temperature for pipe connections is - 5 ^ { \circ } \mathsf { C } to 4 5 ^ { \circ } { C } .Insulation and windproof measures should be implemented,and the connection process shall be adjusted if the ambient temperature is below - 5 ^ { \circ } \mathsf { C } or wind speed exceeds Level 5 during the pipe connection process.Sunprotection measures should also be takenduring connectionoperationsin hotsummerconditions.
3.3.4The connection of underground PE water supply piping systems should meet the following requirements:
3.3.4.1Ppipesandfitingsmustbeconnectedthroughmethdssuchasbutfusinintingorelectrofusionjointing(electrofusionscket jointingreectrusdeictittalitaceosfngetistic transition jointing should be used.
3.3.4.2Electrofusion jointingarerecommended for PEpipeswithanominal diameter less than90mm.
3.3.4.3ElectrofusijntigoudsedtooctPipesfitisdieccessresofrentgradesithlo rate difference greater than0.5g/10min ( \boldsymbol { { 1 9 0 ^ { \circ } C } } 5 | \boldsymbol { \mu } _ { { { \scriptsize ~ 5 } ~ } } | ,and PE piping systems with different standard dimension ratios (SDR).
3.3.5The use of butt fusion jointing should meet the following requirements:
3.3.5.1Fixturessouldbeselectedbasedoipeofitingspecificatio.ecoectiedsofteonectigcompoentseitripe orfittings) should extend fromthe fixtureswitha free lengthat least 10 % of the nominal diameter.Move the fixture so that the ends of theconectingcomponentsareincontact,andalignthecorespondingcomponentstoeconnectedsotattheirisalignmenton the same axis is limited to a maximum of 10 % of wall thickness.
3.3.5.2Theconnectigpartsofpipesorfitingsmustbewipedcleanandtheendstobejinedonpipesorfitingsshouldbeilled perpendicular to itsaxis.The average thickness of continuous miling should notbe greater than 0 . 2 \mathsf {mm } ,and the milled surface must not be contaminated.
3.3.5.3Theendstobejoinedonpipesorfitingsshouldbeheatedusingabuttfusionweldingmachie,andtheheatingtimeshouldbe basedondesignspecifications orsiteconditions.
3.3.5.4Theheatingplateshouldberemovedquicklyafterreachingtherequiredheatingtimeandtheuiformityofmeltingonteated endsshouldbeinspectedandmustshownosignsofdamage.Theconnectingsurfacesshouldbebroughtintofulcontactwith uniformexternal forceuntilanevenandsymmetrical bead is formed.
3.3.5.5 During the pressure holdingand cooling period,thejointsshouldnotbe movedorsubjected toexternal force.
3.3.6The butt fusion jointing must meet the folowing quality inspection requirements:
3.3.6.1Aftertipleedeintustsptedfoadtrtadoalid also be conducted on at least 10 % of the joints.
3.3.6.2Thejointmusthaveauifoandsymmetricalbeadalontheentirecircumferenceofthepipeandthedepth(A)attheloetoint of the bead must not be below the pipe surface.
3.3.6.3Themisaignment (V)atanypointontheoutercircumferenceadjacentothebeadonbothsidesoftheweldingseamshouldnot exceed 10 % of the pipe wall thickness.
3.3.7The operation of electrofusionsocket jointing must meet the following requirements:
3.3.7.1 The connecting parts should be wiped clean,andthe insertion depth should be marked on the pipe end.
3.3.7.2 If the pipe is not round enough toaffect installation,a rounding toolcan be used for adjustment.
3.3.7.3Thespigotndieoiddlayescradofshalleinsertdintoheocketenduntiacstinsertioeptharkand the size fit should be checked.
3.3.7.4Thetwocomponentstobefusedmustbelignedtotesmeaxisbeforetuingonthepowerandspecialtoolssouldbeusedto secure the joints.
3.3.7.5Thevolageatigndlingtiemustmeetedsignspecificatiosorteequirementsoflectrofusioitingmaufacturer
3.3.7.6 During thecoolingperiodinelectrofusionjointing,thejoints mustnotbemovedorsubjectedtoanyexternal force.
3.3.8Electrofusion socket jointing must meet the folowing quality inspection requirements:
3.3.8.1 Scraping and insertion depth marks should be visible aroundthe pipe atthe endof the electrofusion fiting.
3.3.8.2 Molten material should not be overflowing from the joints.
3.3.8.3Theresistancewiresinelectrofusionfitingsshouldnotbeextrudedunlessthefitingsaredesignedwithaspecialstructure.
3.3.8.4Asmalmountofmoltenmateralcanbeseninthebservatiooleofteelectrofusionfitingbutitsouldotberflowing

LESSO

3.4 Pipe Laying

3.4.1Pipelineinstalltionanonlysartertheevatiooftenchbottomndtrnchfoundatioqualtrespectdndproed

3.4.2Non-metalicropesorstrapsshouldbusedforbundlingandhistingduringpipelowering.Trougthborelftingshouldbeavdd topreventpipedamage.Thepipesshouldbehandledwithcaretopreventscratching,twistingorexcesivestretchingorbending.

3.4.3UndergroundPwaterpipesshouldbelaidinawindingandcurvedmannertofollownaturalterrincontours.Thebendradiusshould notbelessthan30timesthenominaldiameterofpipe.Withfitingsoncurvedpipesections,thebendradiusshouldnotbelessthan 125 times the nominal diameter of pipe.Other plastic pipes must be laid in a straight line.

3.5Trench Backfilling

3.5.1TrenchbackfilngsouldbconductedinatimelyanerafterthecompletionfpipelangandqualfiedvisualispectioBefore hydrostatictesting,thebackflingheightonbothsidesofthepipeandabovethepipetopshouldnotbelessthanO.5m,exeptfor theconnectionpartswhich mayremain exposed.Theremaining parts must be backfiled immediatelyafterthe hydrostatictest is passed.

3.5.2Thetrenchmustbinspectedtosuretatallwaterrickstonesoodbocksandotherdebrisinthetrenchhaveeoed before backfilling.

3.5.3Trenchbackflingshouldbecarredoutsymmetricalyandevenlyfrombothsidesofthepipeatthesametimetopreventpipe displacement.Temporaryrestraintscanbeadopted if there isaneed toprevent pipe flotation.

3.5.4Sludgerganicmaterndfrozensomustnotbusedforackfilingtetrenchndthebackfilsoilsouldefreftoes bricks,and other debris.

3.5.5Mediumtocoarsesandshouldbeusedforbackfilingandcompactionwithinthedesignedcenterangleofthepipefoundationand thecompactioncoefficientmustmeetthedesignspecifications.

3.5.6Backfilsoilorotherbackfilmaterialsshouldbesymmetricallayeredfrombothsidesofthetrenchandmustnotbeirectl backfilled onto the pipe to avoid damaging the pipe and its joints.

3.5.7Ifthetrechissupportedbyelsetpils,thesteelseetpissouldnotremoeduntilteackfileachsthid height.Oncethestelsheetpilesareremoved,thevoidsmustbebackfiledandcompactedinatimelymanner.Simultaneous grouting during pile removal can be adopted where environmental impact on the surrounding areasarea concern.

3.5.8Theverticaldeformationoftepipemustbecontroledduringtrenchbackfiling.Forpipeswithinsidediameterofover80mm, temporaryverticalsupportshouldbe installd inthepipeorpre-deformationcontrol measures should be taken.

3.5.9Backfilling in the pipe area must meet the following requirements:
3.5.9.1Lightcompactionequipmentshouldbeusedtoperformmanualbackfilingwithintherangefromthebeddingareaof thepipe bottom to 0 . 5 \mathsf { m } above the pipe top.Mechanical backfilling with bulldozers is strictly prohibited.
3.5.9.2Backfilingandcompactionshouldbeconductedinsymmetricallayers,witheachlayerofbackfilsoilnotexceeding 2 0 0 \mathsf {mm } One-sided backfillingand compactionare forbidden.
3.5.9.3Mechanical backfilingand compaction can be used 0 . 5 m above the pipe top,and mustbe carried out evenly from both sides of the pipe axis at the same time.The soil must be compacted and rolled as specified.

3.5.10Thecompactioncefientofbackfllsoilandtetypesofbackfllmaterialsforpipetrencesustmeetedesignspeifiaions Iftheyarenotspecifiedinthedesign,refertothetablebelow.

LESSO

4、Hydrostatic Test, Flushingand Disinfection

4.1General Regulations

4.1.1Aftertauddscfliftel complywiththerelevantspecifications.Thehydrostatictestcanonlybeconductedafterthfinalweldedjintinthepipingsystemhas completed its cooling period.
4.1.2Thehyrostatictestsouldonducdintostas:prelmartestadmainstTieifpassigtestshoudebasedon allowablepressuredropandalowablewaterseepageasspecifedindesignspecificationsorlientrequirements.Iftherearenodesign specificationsorintrequirementsneorbothiteriacanbeusedasfinalbasisfordeterminingtestaceptancebasedonteactual site conditions.
4.1.3The length of section for the hydrostatic test should not exceed 1 . 0 k m .Forpipeswithaccessories in the middle part, the length of section for the hydrostatic test should not exceed 0 . 5 \mathsf { k m }
4.1.4Wentwoormoredierentpipemateralsareusedintepingsste,tedrostatictestshouldbeondutedseparatelytotesteach material.Ifsepraterostaticstealeoifemtreddotaticstlti accordance with strictest pipe material standard among those involved.
4.1.5 The test pressure for a hydrostatic test must meet the following requirements: Thetest pressureofPEpipes should notbe less than1.5times theoperating pressure,andnot less than 0.8MPa.
4.1.6If the ambient temperature for the hydrostatic test is lower than 5 ^ { \circ } \mathsf { C } ,anti-freezing measures must be taken.The water should be drained and the pressure should be released after the test.
4.1.7Afterpasstdrosatiesttdergdastatesdshdddisinfectforgoecdn network for use.Thepipecanonly becommissioned and alowed tocary water after passing waterquality testing.

4.2 Hydrostatic Test

4.2.1The preliminary test of the underground plastic water pipe must meet the following requirements:
4.2.1.1 The water pressure in the testsection must be slowly increased to the test pressure and maintained for 3 0 ~ { m i n }
4.2.1.2Ifthepsseourinthtsateandddstreprureuttspesseusgrtnsure
4.2.1.3Ifleaagamagisoudatijntsoinstrostaticstustoppdimediatelyrostatict
conductedafterdetermining thecauseand taking rectificationmeasures.

4.2.2 The main test of PE pipes must meet the following requirements:

4.2.2.1 Allowable pressure drop method:

Attheendofthepreliminarytest,stopaddingwaterandallowthepressuretostabizfor3Omin.hepressuredopshouldced 60kPa.The pressure drop should not be greater than 2 0 \mathsf { k P a } afteranother two hours of stabilization,and the hydrostatic test is deemed successfulif both conditionsaremet.

4.2.2.2 Allowable water seepage method:

1)Afterthepreliminarytest,stopadding waterandalowthepressuretostabilizefor60min.Thepressuredropmustbeless than 30 % of the test presure,orthehydrostatictestmustbestopped.Thehydrostatictestcanbere-conductedafterdeterminingthecauseandtaking rectification measures.
2) If the pressure drop is less than 30 % of the test pressure,the water should be immediately drained from the pipeline to reduce the pressure by 1 0 % - 1 5 % ofthetestpressure.Theamountofdrainedwaterduringthepressurereduction(△V)shouldbemeasured.Themaximumallwable amount of water seepage can be calculated using the following equation:

Where: \Delta { V } _ { { m a x } } Maximum allowable amount of drained water (L); （204号 \boldsymbol { V } （204号 Total volume of test pipe (L); \Delta { P } （20 Pressure drop (MPa); （20 E _ { \ast } （204号 Bulk modulus of water; （204号 d _ { i } （20 Inside diameter of pipe (m); （204号 e _ { \mathfrak { n } } （204号 Nominal wall thickness of pipe (m); E _ { \scriptscriptstyle P } （204号 Elastic modulus of pipe material (MPa).

When△V≤atieithep3)and4).eVxterosaticestmustopedndcesirinese removed.Thepreliminarytestshouldbere-conducted.

3）Theresidualpresureinthepipeshouldberecordedevery3minfor0min.Iftheresidualpressureshowsanupwardrendwithin30min the hydrostatic test is deemed successful.
4）If theresidualpressureintepipesowsnouwardtrendwitinminontiueobservationformin.Iftepresuredropiseater than2OkPawithin 90min,the hydrostatic test is deemed successful.
5）Ifneitheroftheabovetwoconionsismettehydrostatictestisonsideredafilure.Thecauseshouldbedeterinedandthe hydrostatic test must be re-conducted after taking rectificationmeasures.

4.3Flushingand Disinfection

4.3.1 Pipe flushing and disinfection must meet the following requirements:
4.3.1 Clean water must be used for flushing.The flushing flow rate should not be less than 1 . 0 { m / s } andcontinuous flushing shall be maintained.
4.3.2 CleanwatermustbeusedforthefirstflushingofthepipeuntilthewaterreachesthewateroutletFlushingprocessshouldbecompleted when the turbidity of thewatersample is less than 3NTU.
4.3.3Thesecondflushgoftemustadutaterthisflusngepipesalboakedfo4ousitanaterotang anavailablecoronceraiofotsstanmg/LFushteeitanwategainuntilwateualityttdeemdiissae

LESSO

IV. Water Supply System for Buildings

1、Material Transportationand Storage

1.1Pipesanditinssodandiareduringtrasporatioadingndoadingselloitndinodt becontaminatedorcomeintocontactwithsharpobjects.Theyshouldbestackedsecurelyduring long-distancetransportationto prevent damage.Pipes and fitings must not be thrown,dropped,rolled or dragged.

1.2Pipesandfitingsshouldbestackedindoorsbytheirtypesandsizes.Smal-diametercoilpipesmustbekeptinboxedpackaging. Straight pipes should be bundled,with each bundle not weighing over 5 0 \mathsf {kg }

1.3Pipesandfitingsstoredintemporarywarehousesshouldbekeptintheiroriginalpackagingandshouldbeunbundledoruboed individuallybasedonsiteconditions.

1.4Pipes,fitingsand rubberpartsshouldbestored inawellventilated warehouse witha temperaturenot greaterthan 4 0 ^ { \circ } { C } They must not bestored outdoors foran extended period orexposed to direct sunlight.

1.5Thestackingareasforthepipesmustbeflatwithpropersupportatebottomoftepipes.Thesupportshouldbespacednotgreater than1.00m,ndteidthshouldnotbelessthanO5m.Teoverhanglengthoftepiesshouldoteceed.50m,andtheacking heightshould not be over 1.50m.The stacking height of pipe fitings should not be over 2 . 0 0 \mathsf { m } ,and themaximumstacking heightof metalfitingsis1.2Om.Thewarehousesandstorageareasshouldbeawayfromheatsourcesandopenflames,ndmusteequipped with fire safetymeasures.

2、Design

2.1 General Regulations

2.1.1Thedesignofplasticwaterpipesforbuildingsshouldconsiderthesystem’soperatingpresureandtemperaturetoelecthe appropriate pipe materialand itsS or SDR series.

2.1.2Thepipelayoutandinstalationshouldbedeterminedbasedontheuserequirementsofthebuilding,thepipematerial andits material properties.Thesame type of pipes should be used for areas with thesame function in the building.

2.1.3Pipechasesshouldbepre-reservedwhen horizontalpipes(including horizontalbranchpipes)areembeddedinthe wal.

2.1.4Polyledsdim are required with pipe supports,or secured with fixed brackets when pipe supports are not provided.

2.1.5When cold water pipes are embedded within wals,the following requirements must be met:
2.1.5.1 The pipe diametershould not exceed 25mm;
2.1.5.2Theburialdepthofthepipesalensurethathecementmortarprotectivelayeroteoutersieofthepipeshouldaveathickne
of less than 10mm;
2.1.5.3Pipecampsustbistaledinpipecassndtheistaationspacingetweenpipampsouldtexceed.

2.1.6 Insulation measures mustbeimplemented if moisture condensation is likelyto occur on the surface of the pipe

2.2 Selection of Pipes

2.2.1For plastic water pipe engineering used in cold water systems,the nominal pressure P N of the pipe can be calculated using the followingequation:

Where:PN - Nominal pressure of pipe (MPa); C _ { \bar { A } } 一Safety factor of the pipe applied in engineering can be taken as 1.2 to 1.5; （20 P _ { m } -Operating pressure of system (MPa); f The pressure reduction coeficient of the pipe’s working temperature can be selected from Table 2.2.1 of this manual.

LESSO

2.3Pipe Layout and Installation

2.3.1Vrticalwaterppesshoudbeinstalednearwalcorersorolumnsherewateusingapancesareintensivelycated.Horontal waterpipesshouldbelaidalongwalsorslabs.Asverticalpesexposedinpublicareasareatriskofexteralimpact,aprotective pipeshouldbeaddedtoteouterwallftewaterpipe,andthetopoftheprotectivepipeshouldbeatleast1ommaboveground.

2.3.2Afixedsupportshouldbeinstaledwithantieakagemeasuresatthelocationwhereacoldwaterverticalpipepassesthroughafloor slab.Thegapbetweentheouterwalofthepipeandthefloorslabshouldbefiledwithfineaggregateconcrete.Apolyinylloride (PVC-U)protectivesleeveshouldbeinstaledatthebaseofthepipeandembeddedinthefloorlevelinglayer.Thetopofthesleeve must beat least 7 0mm higher than the finished floor surface.

2.3.3Metalwaterprofsleevesustbepreembeddedinlocationswherepipespassthroughexternalwalsofbasementsreinforced concretepools,rwatertankwall.Iletpipespassingthroughpoolsorwatertanks,aswellaspipesectionsinsidepoolsorwater tanksshouldbeconstructedofcorosionresistantmetalpipes.Leak-proofmeasuresshallbeapliedtotheannulargapbetweenthe sleeveand the pipe wall.

2.3.4Pipesshouldnotbeexposedalongastove,norshouldtheybeplacedabove kitchenapliancesorheatingequipment.Tenet distance betweenan exposed vertical pipe and a household gas water heater should not be less than 2 0 0 \mathsf {mm } ,and the distance to the edgeofahouseholdgasstoveshouldnotbelessthan 4 0 0 \mathsf {mm } .Ifcertainactualconditionsareunavoidableandthesurface temperatureofthepipeexceeds 6 0 ^ { \circ } \mathsf { C } ,heat insulationmeasuresmustbe taken.

2.3.5Whencoldwaterpipesareconnectedtowater heaters,measuresshouldbetaken toprevent hotwaterbackflowbasedonwater pressure fluctuations in the pipe network and the water heaters’ functions.

2.3.6Anti-freezingandinsulationmeasuresmustbeimplementedifwaterpipesarelikelytofreeze.Lightweightfoam-basedmaterials should be used for insulation.

2.3.7Forlightolodrsparentpesistadindorsndpolyolefinpipeldutdors,lighteingmeasuessoudbetakeote pipe surfaces.

2.3.8Protectivemeasuresmustbeinplacetosafeguardinletpipesandpipespasingtroughsetlementorexpansionjointsinbuildings fromdamage.Angledtursrerecommendedforistalation,andthelngthoftheangledsegmentshouldbedeterminedbasedon thebuilding’ssettementamount,aswellasonnectionsofpipesndfitigs.Teminimumlngthoftheangedsgmentmustbeat least 5 0 0 \mathsf {mm }

2.3.9HorizontalylaidwaterpipesshouldhaveasloeofO02toOondtheslopeshoulddiectheflowtowardsthedrainagepoint

2.4 Piping System Thermal Expansion and Compensation

2.4.1Pipingsystemsustbeprovidedwitfiedsupportsorracketsatinterals.Ifthespacingbetweetemexceedstespeciidimi thermal compensation measures should be taken.

2.4.2Theaxialexpansionandcontractionofcoldwaterpipesduetothermal expansionorcontractioncanbecalculatedusingthe following equation:

Where:L- Axial expansion and contraction of the pipe section (mm); （204号 L —— Length of the pipe section ( \mathsf {mm } ) a 1 一Linear expansion coefficient of the pipe ( 1 / ^ { \circ } \mathsf { C } ) ；Forpipes, it can be 1 5 x 1 0 ^ { - 5 } to 2 0 { x } 1 0 { - } 5 ( 1 / { } ^ { \circ } \mathsf { C } ) \Delta t 1 ：Temperature difference { \mathfrak { ( C ) } } \Delta t _ { s } 一Maximum temperature difference of water in the pipe ( ^ { \circ } \mathsf { C } ) \Delta t _ { g } ：Ambient temperature difference around the pipe ( ^ { \circ } \mathsf { C } )

LESSO

2.4.3Freearmcompensatorsshouldbeusedinpiping systems.Long straightpipesectionscanbeplacedaroundthebeamsand columns of buildings for free arm compensation.The minimum free arm length L _ { a } can be calculated using the following equation:

Where: L _ { a } Minimum free arm length (mm); K 一Material coefficient; Use27 forPE pipes; L— Axial expansion and contraction of the pipe section (mm); （204号 d n Nominal outside diameterof the pipe (mm).

2.4.4Afinishedopcompensatorcanbeusedwhenthediameteroftepipesectionislessthan4mm.Theinsidediameteroftheloop compensatorshouldbedeterminedbasedonthepipematerialandsouldnotbelessthan15imestheoutsidediameteofthepipe

2.4.5Thermal compensation may not be needed for cold water piping systems under the folowing conditions:
2.4.5.1 Underground pipes;
2.4.5.2 Exposed or non-buried concealed pipes secured with fixed supports;
2.4.5.3 Vertical and horizontal sections of polyolefin pipes equipped with metal pipe supports;

2.4.6Whenanexposedverticalpipeisonnectedtoahorizontalbranchpipe,afreepipesectionwithalengthofatlast4ommhould be installed on the horizontal branch pipe.

2.5 Piping System Support

2.5.1Fixedandslidingsupportsmustbeinstaledifapipingsystemundergoesaxialthermalexpansionduetowatertmperatureor ambient temperature changes.

2.5.2Fixed supports or brackets must be installed in the folowing areas for indoor piping systems:
2.5.2.1 Branch parts of vertical pipes connected to horizontal pipes;
2.5.2.2 The downstream side of a calculated free arm section;
2.5.2.3Bothendsofafxedupportspacedatmaximumdistanceforstraightpipesectios,asspecifiediTable2.5oftisanual

2.5.3The maximum spacing L for fixed supports on straight horizontal pipe sections should be selected according to Table 2.5.3.

2.5.4Pipesdprtodturaoli climbing,or hanging other pipes.

2.5.5Themaximumspacing betweensupportsorhangersforexposedorconcealedcoldwaterpipesshouldbeselectedaccording to Table 2.5.5

LESSO

2.6 Hydraulic Calculation for Pipes

2.6.1Thefrictionalheadlossperunitlengthofplasticcoldwaterpipesforbuldingscanbecalculatedusingthefollowingequation:

Where:i -Frictional head lossper unit length of cold water pipes [kPa/m (100mm/m)]; （204号 C _ { h } （20 -Hazen-Williams coefficient can be takenas 140; （204号 d _ { j } Calculated inside diameter of the pipe ( \mathsf { m } ) qg -Design flow rate of the water pipe section ( m ^ { 3 } / s )

2.5.6Theminorheadlossoftepipingsystemcanbetakenasapercentageofthefritionalheadlossofthepipenetworkbasedonthe connection type of fittings,and should follow these requirements:

2.5.6.1Whentisidedameteofteipefitingacssorisosistentittsidmeterofthiendckttio isused.Ifateeforwaterdiversionisadopted,itisrecommendedtotake 2 5 % to 30 % ofthefrictionalhead loss. Ifamanifoldisused forwaterdiversion,it isrecommended to take 1 5 % to 20 % of the frictional head loss.

3、Construction

3.1 General Requirements

3.1.1TechnicalrfingssouldbeonductedbforetheconstructiooftheeengieinggisEsureositeatelectri and other facilitiesare in place.

3.1.2Theworkersforpipeconstructionmustbecertfiedandtechnicalytrained.Teyshoudunderstandthebuildingstructuresandshal befamiliarwithconstructiondrawingsandabletocoordinatewithothertypesofworkers.Theyshouldalsobeknowledgeableon material properties,installationmethods,andsafetymeasures.

3.1.3Materials and machines used in construction must meet the folowing requirements:

3.1.3.1Pipesfitindeedateralsustbispectedsedosispeiaisroductsustavefctoriated testreportsthatmeetnationalstandards;

3.1.3.2 Pipesand fitings must undergo quality inspection,and substandard products should be rejected;
3.1.3.3 All equipment used in construction must be inspected for quality.

.1.4The following preparations should be made before pipe installation:

3.1.4.1 All reserved holes and sleeves between building floors must be checked for accessibility;

3.1.4.2Ifacoldateeassstoghoceteal,tgthoftprembeddeddlyodeeodfu withthe wallfinish.When metal sleeves are used,theinner opening of the sleeves must be smooth without burrs;

3.1.4.3The inside diameter of the reserved hole or sleeve for cold water pipes must be 3 0 \mathsf {mm } larger than the outside diameter of the pipe.Pre-embedded metal waterproof sleevesshouldbeusedifpipespassthrough theconcretewalsofbasements,pools,or water tanks.

3.1.4.4The reserved pipe chases in wals must be checked to ensure they meet the design specifications;

3.1.4.5 The horizontal excavation of the pipe chases in walls should not exceed 3 0 0 \mathsf {mm } ,unless permitted by structural designer; 3.1.4.6Ifthereismajordiferencebetweenthetemperatureofthepipestorageareaandindorconstructionsite,thepipessouldbe placedindoorsforacertainperiduntilthesurfacetemperatureofthepipesislosetotheambienttemperaturebeforeinstalation

3.1.5 Piping construction must meet the following requirements:

3.1.5.1 Product markings on the surface of pipes and fitings must face outward during installation;

3.1.5.2Theanulargapwherepipespassthroughthewallofpolsorwatertanksshouldbflledwitwaterproofsealanthatdoesnot pollte thewater.Thefilingwidthshouldnotlesstanone-thirdofthewallthickness.BothsidesshouldbefledwithM15ement mortar,and the innerand outer surfaces of the wallor pool shouldbe scraped flatafter filling;

ee 3.1.5.4Pipesmusttisdoforblraieduringistalltiondoudotfiblyotedte other equipment;

3.1.5.5Undernocircumstances shallthread-cuttng or heating beapplied directly tothepipe wallofanyplasticpipe;

3.1.5.6Dirtorforegnmateralssouldbeprevetedfromenteringthepipeduringinstaltion.Ppendsmustetemporailysaleddur installationbreaksoraftercompletionofinstallation.

3.1.5.7Thesurfaceoftepipesouldotbeontaminatedordamagedndthesuroundingareamustnotbexposedtoatotective measuresmustbetakenonthe installed products.

3.1.5.8Forpipesembeddedinalsandflors,itisrecommendedtomarkthepiperoutingonthesurfaceafterthecompletioofwal plastering and sub-base construction.

LESSO

3.1.6The installation of cold water pipes passing through flor slabs must meet the folowing requirements:

3.1.6.1Afterthepingsystemhaspassdthehydrostatictestandbeenequippedwithleakpreventionmeasures,theanuargaparound theverticalpipeandteflooslabshalbefiledwithfineaggregateconcreteC2fineaggregateconcreteshouldbepouredintwo stages.The first pour should reach two-thirds of thefloor slab thickness.Once the concrete has reached 5 0 % of its designed strength,theremainingone-thirdshouldbefiled.Beforepouringthefineaggregateconcrete,formworkshouldbebultatthe bottom of the floor slab.The concrete at the bottom should not protrude from the slab surface;
3.16.2ArigidpolinylchlorideprotectivesleeveshouldbeinstaledinlocationswherecoldwaterpipespassthroughflooslabsThe protective sleeve must be 7 0mm above the finished floor surface,and should be embedded in the leveling layer of the floor during construction;
3.1.6.3 During the construction of the floor layer,a water barrier ring with a height of 1 0mm to 1 5mm and width of 2 0mm to 3 0 \mathsf {mm } should be formed around the protective sleeve;
3.1.6.4Forpipecolasorsatingriseldisfixdsupposustbistaldintemdeoftfloofrseadsin the building design.
3.1.7Safety management during piping construction must meet the folowing requirements:
3.1.7.1Constructionpersonelmustotwalkorstandonpipestocarryoutanyconstructiooperatiosandpipesshouldnotbeusedfor pulling,climbing,or hanging other pipes or pipe accessories;
3.1.7.2Openflamesareproibitedatheconstructionsite,specialynearleaningagents.Firesafetyquipmentmustbeavalablein storage places as per regulations;
3.1.7.3Pipingsystemsmustundergoahydrostatictest,andpneumatictestshouldnotbeusedasasubstituteofhydrostatictest.

3.2 Pipe Connections

3.2.1The socket fusion jointing of polyolefin pipes and fittings must meet the folowing requirements:
3.2.1.1 The connecting ends of pipes should be beveled, with a bevel angle not lower than 3 0 ^ { \circ }
3.2.1.2 Dirt must be cleaned on the surfaces of pipes,fitings,and socket fusion joint heating tools;
3.2.1.3Thesocketdepthofthefiting should bemeasured,andthedepth should be markedon thesurfaceof the pipe;
3.2.1.4Theoutersurfaceof thepipeandtheinnersurfaceofthefitingshouldbe heatedwithasocketfusion tool.Theheating temperature and time must be based on the specified technical parameters;
3.2.1.5Theheatingtolshouldbeicklyemoedafterheatingndthepipeshouldbeisertedintotesocketftefitingwitio externalforceuntitreaches themarkeddepthonthepipe.Moderateforceshouldbeapplieduntilacompletebeadisformedat the end of the fitting's socket;
3.2.1.6 The connected components should be protected from external impact and alowed to cool naturally;
3.2.1.7 For pipes with a diameter larger than 75mm,the connection should be performed usingatabletop tool.
3.2.2The butfusion jointing of polyolefin pipes and fitings should meet the following requirements:
3.2.2.1 The but fusion jointing should be performed using a tabletop tool;
3.2.2.2Beforecoctionteabetoptoolsouldinspectedndcalbatedeonectingomponnts(eiterpisofiin)ust be aligned on the same axis after putting on the tool, with a deviation not exceeding 10 % of the wall thickness;
3.2.2.3Amilngcuttrontetableoptoosoudeusedtotritheconnectinsurfacsofpipesandfitings.Temilldsfacsmust be smooth,flat,aligned,and perpendicular to the axis;
3.2.2.4Theheatingplateonthetabletoptolaswellastheendsofpipesandfitingsmustbewipedtonsuretheyarelean;
3.2.2.5Theendsoftheweldedpartsshouldbeheatedusingtheheating plateonthetabletoptool,andtheheatingtimeand requirements should be based on design specifications;
3.2.2.6Theheatingplateshouldbequicklyremovedafteheatinganduifompressureshouldbeapliedonthetwoeatedsurfaces. uniform ∞ -shaped bead is formed around both the innerand outer peripheries of the joint;
3.2.2.7The connected components should be protected from external impact and alowed to cool naturaly.
3.2.3The electrofusion jointing of pipes and fittings must meet the following requirements:
3.2.3.1 The power of the electrofusion machine should be inspected to ensure it is functioning;
3.2.3.2 The socket depth of the fiting must be measured and marked on the surface of the pipe;
3.2.3.3Aspecialtoolshouldbeusedtoscrapeoftesurfacelayerofthepipe’sconnectingpartinathoroughandevenmanner;
3.2.3.4 The pipe end must be beveled at an angle not lower than { 6 0 } ^ { \circ } ：
3.2.3.5Theconnectingsurfaceofthepipeshouldbewipedwithacleandrycloth.Ifhereisoilonthesurface,acleandryclothwith acetone or 9 5 % anhydrous alcohol should be used for wiping;
3.2.3.6 The voltage,current,and time must meet the design specifications;
3.2.3.7 After turning off the power,unplug the power connector,and wait for natural cooling.

LESSO

3.3 Indoor Pipe Laying and Installation

3.3.1Indoorwatersupplyplasticpipesshouldbelaidafterthecompletionofmaintructuralworks.Exposedpipesshouldbeinstaledafter thecompletionofbuilding’sfinishingworks,ndindoorundergroundpipesshouldbeinstaledbeforepouringconcrete.Vertical pipesshould be installed before horizontal pipesare laid.

3.3.2IndoorundergroundppssoudnstaldintostasAfterthistallaionofindooppesisompleeddthested 500mmto7osidetteriaostructioudmporarilypededndtedldblyle The final connection shall be complete when outdoor pipes have been laid.

3.3.3Indoor underground pipe installation must meet the following requirements:
3.3.3.1Pipes shouldbe laid ina newly excavated trench after the ground is compacted;
3.3.3.2During renchbackfiling,teareaaroundthepipemustotcontainsharpoectsorlargestones.Asandlayerwithatickesot less than 7 \mathsf {mm } should be used for filling;
3.3.3.3 The depth of soil cover above the pipe top must not be less than 300mm;
3.3.3.4Ametalprotectiveseevemustbinstaledattheaseofverticalpesifpipespssthroughindoogroundflorsab.etopofte sleeveshouldextendatleast1ommabovethefinishedfloorsurface,andtheinsidediameteroftheslevemustnotexceedthe outside diameterof thepipe bymore than15mm.Thebottmof the sleeve shouldrestonthesurface layerof the ground during construction;
3.3.3.5 After installation,theareaaround thepipeshould be protected fromexternal impactand heavy objects.
3.3.3.6 Pipes should be laid below the frost line if there is a possibility of freezing indoors.
3.3.4The installation of pipes passing through floor slabs must meet the following requirements:
3.3.4.1The location,diameterand accessibility of reserved holes and sleeves should be inspected;
3.3.4.2 Vertical pipes should be installed from the bottomup,floor by floor;
3.3.4.3Protectthepipesurfacefromdamage whenpipespassthroughholesormetalsleeves.Pipeswithvisiblescratchesordamage should be replaced immediately;
3.3.4.4Theelevationoftheconnectionpartsbetweenhorizontalandverticalpipesshouldbere-measured.Verticalpipesshouldalsobe marked to determine the direction of the horizontal pipe’s outlet;
3.3.4.5 Pipes and fitings can be prefabricated for sectional installation;
3.3.4.6Wooden formworkshouldbebuiltoldpipesduringpositioning.Fixedorslidingsupportscanthenbeinstaledoncedesign specifications have been met.

3.3.5The installation of non-buried horizontal pipes with a diameter larger than 4 0 m { m } must meet the following requirements:
3.3.5.1Pipesshouldbelaid basedonthebuilding structureanddesignspecifications,and marks mustbe madeonthe wall;
3.3.5.2Thepositionsofixedandslidingsupportsshouldbedeterminedbasedondesignspecifications,andmarksmustbemadeon
the wall;
3.3.5.3 Fixed and sliding supports should be installed based on the designed slope;
3.3.5.4Whenprefabricatedcombinedpipesareusedforinstalation,tepipesshouldbesecuredwithsupportsinatimelymaner;
3.3.5.5 Metal pipe clamps with smooth inner surfaces should be used.

3.3.7Theinstalationof exposed branch pipes ordistributionpipes withadiametersmaler than 40mm must meet the following requirements:

3.3.7.1Afterinstalltionthesupportsshallensuretattecarancebetweethepipendfinisedsurfaceshoudotexcedmm;
3.3.7.2The pipeslopemustmeetthedesignspecifications.

LESSO

4、Quality Acceptance

4.1Acceptance Requirements

4.1.1Thequalityacceptanceofthewatersupplyplasticpipeengineeringforbuildingsshallcomplywiththerelevantregulationsofthe currentnationalstandard:CodeforAcceptanceofConstruction QualityofWaterSuppyDrainageandHeatingWorks(GB50242)

4.1.2Themain inspectionitemsforthequaityacceptanceofthewatersupplyplasticpipeengineeringforbuildings mustmete following requirements:

4.1.2.1AhydrostatictestsouldbecariedoutinaccordancewithArticle4.13ofthisrequirement.Concealedpipesmustudegoa hydrostatictestbeforebeingenclosed;

4.1.2.2Thespecificains,typsSoseriameersandistalltionpositosofpiesusteetedsits;
4.1.2.3Pipesandupportsmustbeecured,andtheirpositionsandspacingmustbebasedonrelevantregulationsofthisanual;

4.1.2.4Specificwaterfituressouldbetredoasreuiredtoverifyunobstructedflow.Forbuildingswithspecialrequirementswater flow capacity tests should be conducted in layers and sections.

4.1.3Hydrostatitestsanearedutinagesbasedonteconstructioprogress.Howeveradrostaticstustboducted again before the entire piping system is installed.The hydrostatic test must meet the follwing requirements:

.1.3.1 The test pressure must be 1.5 times the maximum operating pressure,and not less than 0.60MPa.
.1.3.2Tehdroaticstfogtmusttiias.fiisotsdogsod be taken: 1)Sealallwateroutletsintetestpipesection,fllwithwaterslowlyandexpeltheairfromthepipesatthesametime; 2) Once the piping system is filld with water,check the watertightness of the system; 3)Pressurizethesystemafterconfimingnoleakageduringthewatertightness inspection.Ahandpumpshouldbeusedforslow pressurization,and the pressurization time should not be less than 10min; 4)Aftereachingthespecifiedtestpressure,stoppressurizationandmaintainthepresurefor1hour.Thepresuredropsouldnot exceed 0.05MPa; 5)Maintainthepresureat1.15timesthemaximumoperating pressurefor2hours.Thepressuredropshouldnotexceed003MPa and all joints and connections should be inspected for leaks.
.1.3.3Aftertrosatistisompleedtwaterieallrdeforeputingtintitsalld disinfectedandsamplessalbeinspectedbytheelevanthealthepartments.eaterualityfterinspectionshaloplywith

therelevant regulationsof the current national standard:Standards for Drinking Water Quality(GB5749).

LESSO

LESSO GROUP (STOCK CODE:2128.HK)

GUANGDONG LIANSU TECHNOLOGY INDUSTRIAL CO., LTD.

Production Base: Liansu Industrial Estate,Longjiang Town,Shunde District,Foshan City,Guangdong Province 528318,China

Sales Tel: (86) 757 23379211 Fax:(86) 75723378980 E-mail:oversea@lesso.com Asia-1:(86) 757-29223015 Africa-1:(86) 757-29226356 Middle East:(86)757-29226355 Hotline: +86 4009212800 Asia-2:(86) 757-29220500 Africa-2:(86) 757-23379211 South America:(86) 757-29220501 (Extension Number:1701)

\* This catalog has been prepared as a support guide.Under no circumstance shall LESSO assume any liability or responsibility with the information in this catalog. Every effort has been made by LESSO to provide accurate and up to date information.

All Rights Reserved 2025.10