East Alligator district centre water supply assessment : Kakadu National Park
D . Pidsley
Jamieson, M.; Pidsley, D.; Paiva, Jerome
E-Publications; E-Books; PublicationNT; Technical Report ; 26/1991
Made available via the Publications (Legal Deposit) Act 2004 (NT).
Water-supply -- Northern Territory -- Kakadu National Park; Groundwater -- Northern Territory -- Kakadu National Park; Kakadu National Park (N.T.)
Power and Water Authority
Technical Report ; 26/1991
1 v. : ill., maps ; 30 cm.
Check within Publication or with content Publisher.
Technical Report WRD91026 Viewed at 15:07:48 on 29/07/2010 Page 104 of 107. !2zincificatiat (Figure 5) is the selective raroval un&! r acidic condi t.icns of zinc fran brass 1oihi.d1 gene~ally contains ,3rCt.1OO 30% zinc and 70t ccpper.. 'Ihe camonly accepted theory of dezincification is that the brass dissolves" the zinc ions stay in solution ar:d the ccp~r.. being m::Ire noble .. plates back on (Fontana and Greene, 1967) .. The result is a POraJs (.~per st...'"Uct.ure havin; little st..-ength. Comen grade brass ~ seats suff,~r rap id failure t grcovirq, =idered to ]'" due to a cancination of initial dezincifil:at:ion and t.~en erosicn corrosicn of the residual PO.rOJS ~;er st..."Ucture (AMI:EL. 1984). Corrcsicn of galvanised iron sel:vice piQes has occ:Jrred as for retiOJ.l.aticn !Ie-ins crentioned above.. However, ultimate failure is 51-ewer than for cq;per because of. tbe tetter adherence of the corrcsicn layer. ?ranatlJre failures of t..~e standaJ:"d o:pper solar collec+"-e.tS arxi steel arx:I cq;:per hc,t 'IGlter stora;re tar.ks are a regular OCCJr:-ence. O.I;lrcsolvenc.l attadc. en. !:he ~per pipeworl;., dezincification corttBicn of brass fitti..rT;s and WLLCSicn of steel ccmponents apt=ear to be t..~ :min causes. 4.7 Coc:m:icn llesistant PllmIbirq Galv.mizeC iron and c-:::pper pipes" and ccmcn brass tubes and fittirgs a...""e nOI!:. ~ori tted in hOJSe plLmbin; in the coastal cclrrasive supply areas. '!he fol!Otfirq cor=csion resistant :naterials are nc:w used: L Tappin; saddles: Reir.orced plastic (e.g. Hardii=llas) with dezincification :-esistam: (DR) brass ferrules to AS 2345" 2.. Service p i~ fran the nain to l:he lee.: Class 12 P'.l:. 3. Meters: Cezinci!icati.cn :::-esistant. and !.o::a:t:.ed undergr~nd in a 9recast /::ox ",it..'1 a 4. 5. mm 05101520 1 , , !)R brass cre'l:er cock. eelC1lol grcund eliminates ara suscep !:able to darr..age. FUtt:'ng the rretets ?V:. upstands which fbt and cold pip~rK within t1.lildings: Class 16 polyi:::uty!.er:.e CPS) to AS 2642.2 wit."1 canpressicn union type joints and acetal fittin;s in non-e.:<posed locations" or DR brass tubing to AS 1572 in exposed locations.. Class 16 E9 has a pressure rat..in,; of 0.48 MPa at 95C. '!'apware, val V'eS and. brass. Q.J.arter-turn preferred. cornbiraticns: DR ceramic disc tapware Rei.'"'lforced. :Jlastic t.appin;; saddles have been used satisfactoz:-il.y for Sate ti.me as has Class 1.2 ~ se!;'V'ice pipe. Bec3use of t..'1e high ccrrcsivity of t..~e '-.laters it is not kncwn at this stage it: DR brass to AS 2345 and tube to AS 1572 ...,il1 be totally adequate. Installations are :::ein; :ronitored and. no failures have t::een obset";ed over a 9 ilDnt.;" pericxi to date. !:R prq;::erties of brasses can be .reduced Cy ovemeatirq. Consequently, joinin; brasses to PB or.PVC is by rteehanical r:eans '..n.thaJl: brazitxJ. '!he several PS jointir'g systems available have .been st'..tdied and carpression union t:,;pe fittin;.s are the only !:yf:e pe::mitt.ed. .. ~ has a CUr:::rreter har-i....ness of 60 ;,hich is just wi thin the te:cn.i te attack ra.nge ~ Tests conducted by the CSIRO in 1984 ccnfi!:M that termites in the Darwin area are able to oenettate l?9 pipe ext.ensi....-elv. Consequently, it is only installed within l::ui1.dings and under :e.t:m..ite treated sl.at:s .. At this stage euOed:IEnt. of PB in concrete is not: pe::r.'.itted. However, it is ;;::cssible that after exnerience is gained ~nt ..,ill be all~ beCause P.B is unders tcod. to ;.edom satisfactorily in such situations .. Q.Jidelines for the use ot: materials in the coastal corrosive supply areas have been !?rcduced tv l1illin; and Partners (1986;.
Aboriginal and Torres Strait Islander people are advised that this website may contain the names, voices and images of people who have died, as well as other culturally sensitive content. Please be aware that some collection items may use outdated phrases or words which reflect the attitude of the creator at the time, and are now considered offensive.
We use temporary cookies on this site to provide functionality.
You are welcome to provide further information or feedback about this item by emailing TerritoryStories@nt.gov.au