When installing a pipeline by theopen-trench method, the pipelinezone is precisely defined. The con-structionofthepipelinetrenchissub-ject to a number of regulations, in-cluding DIN 4124 „Excavations andTrenches“, which precisely stipulatesthespecificationsforworkspacewidthandinstallation.Theseensurethatthesoilsurroundingthepipeispreparedinsuchawaythatthepressurisedme-dium-bearing pipe is protected fromexternalinfluences.DINEN805andDVGW Directive W400-2 stipulateembedding the pipe in sand or finegravel.
DVGWWorksheetW400-2stipulatesfor this purpose amaximum particlesizeof22mmforroundmaterialsand11 mm for crushed stone sand andchipmixes.Onlyinthiswaycanpointorlinearloadsonthepipecausedbyunsuitablematerialsinthepipetrenchbeprevented.
egeplast egelen® pipes can also besupplied with an extremely resistantprotectivecoatingforusewithtrench-less installation techniques and ren-ovation procedures. Please refer toChapter5“TrenchlessInstallationandRenovation” and Chapter 6 “Detect-ing the installed PipelineandCheck-ing Integrity” for additional informa-tion.
MaterialPolyethylene has been continually de-velopedsinceitwasfirstusedasapipematerialin1957.Abalancedpropertyprofileisimportantforapplicationasapipematerial.Awiderangeofmaterialproperties ismonitored so thatapipe
canbemadefromthePErawmaterialthatcansatisfytherequirementsonthebuildingsiteforgasorwatersupplies,andforsewagedisposal.The European standards are differentaccording to application: EN 12201describes drinking water pipes; EN1555,gaspipes;andEN13244,sew-agepipes.Toallowabetterassessmentofthemate-rial,theDVGWhas,inWorksheetGW335,selectedtheparametersassociat-
WorksheetGW335describes the re-quirements for polyethylene pipingwhich isassumed tobe loaded solelyby internal pressure; i.e. the piping isbedded in sand inanopen trench in-stallation.
Productionegeplast is a member of the Quick-Switch partnership. TheQuickSwitchsystem,patentedbyegeplast,allowstheexternaldiameteroftheextrudedpiping to be varied accurately overmultiple dimensions during the run-ningextrusionprocess.Furthermore,itworkswith cooling sections of up to85mlength,whichleadstoextremely
warm storage is specified in Work-sheetGW335.Theshrinkageofege-plastpipesliesatca.1%.Adherence to dimensions and toler-ances,described in thecurrentbodyofregulations,isanabsolutemust.Forthis reason, egeplast operates withhundred percent ultrasound monitor-ingoftheproducedpipes.
egeplastegelen®pipesaremanufac-turedaccordingtoENstandardsandDVGWdirectivesandcarry,depend-ing on their application, the DVGWregistrationnumberortheDINCertcomarkofconformity.
ScopeofapplicationThe installation instructions apply tosoil covered egeplast egelen® pipesmade of HDPE in accordance withDIN8074andDIN8075foruseasdrinkingwater and sewage pressurepipelines, and as gas pipelines. Thepipe joints and pipeline componentsmustberatedforusewiththeirrespec-tiveoperatingpressures.
Pipes are to be checked forsound condition and full la-bellinginaccordancewiththe
DVGW regulations before laying inthe pipe trench. Grooves, scratches,andlaminarabrasionsonthepipesofupto10%oftheminimumwallthick-nessarepermissible.Pipeswithdam-ageexceedingthisextentmaynotbeinstalled.
Thepipetrenchistobedugoutinac-cordancewithDIN4124(trenchpro-fileandsheeting)andDIN1998(lay-outofpipelines inpublicareas).Theminimum covering for gas pipelinesis 0.6 to 1.0m, although the cover-ingcanbereducedto0.5mforsec-tionsup toca.2.0m longwhichdonotcarryaheavyload(frontgardens,pavements).Drinkingwaterandsew-agepressurepipelinesaretobelaidatadepthof1.0to1.8m(accordingtoclimateandgroundconditions)safefromfrost.Applicabletotheconstruc-tionofwaterconduitsis,furthermore,DVGWWorksheetW400-2.
3.5.2 Installation,OpenTrenchMethodWithaSandBed
3.5.3 JoiningTechniques
Weldability of PE 80/PE 100 pipeswithmouldedfittingsWeldingtogetherofegeplastPE80/PE100pipes,andwithstandardisedmouldedfittings,ispossibleforHDPEusingthe
The market offers a complete rangeof accessories for pipelinesmade ofpolyethylene. Adapters from PE tothevariousmaterialsusedinpipelinenetworks are available frommultiplemanufacturers. In principle, the alter-nativeofcreatingaconnectionusingaflangedjointisalwaysavailable.
Polyethylene is an organic materialand consists only of carbon and hy-drogen.Ithasawhollyneutralimpactontheenvironment.PE,beingather-moplastic,canberemeltedanalmostunlimited number of times and proc-essedintonewproducts.Pipeoff-cutsand discarded plastic pipe material,which, for example, accumulate dur-ingtheinstallationofplasticpipesys-tems, should thereforebe recycled ifatallpossible.
At thestartof1994, theKunststoffro-hrverband (KRV), together with theGütegemeinschaft Kunststoffrohre(GKR),hadalreadyintroducedana-tionalcollectionandrecyclingsystemforplasticmaterials,which is freeofcharge for the trade and its custom-ersandincorporatesanobligationtotake back these materials. This envi-ronmentally conscious system elimi-natesdumpingorincinerationtogeth-erwiththehighcostswhicharisefromdisposalbythesemethods.
Recycling boxes are provided on aloanbasis to the customeras collec-tioncontainers.Theplasticpipemate-rial,atleastpartiallycleaned,isthenthrown into these boxes. Once theboxes have been filled, their collec-tionandexchangeforemptyboxesisarranged.Onlyboxeswhicharefilledexclusivelywith plastic pipematerialare taken. The recycling boxes arethen brought, via regional collectionpoints, to a recycling plant in whichthecollectedpipematerial is sorted,cleaned,andcut intosmallpiecestobe employed subsequently for otheruses.
