Umbhobho wentsimbi we-AS 1579ngumbhobho wentsimbi odibeneyo we-butt weld osetyenziswa ikakhulu ekuthuthweni kwamanzi namanzi amdaka onobubanzi obungaphandle obuyi-≥ 114 mm kunye neenqwaba zemibhobho ezinoxinzelelo olulinganiselweyo olungadluli kwi-6.8 MPa.
Iingqumba zemibhobho ngamalungu angqukuva aqhutywa emhlabeni kwaye azisetyenziselwa ukulawula uxinzelelo lwangaphakathi.
Ububanzi obuncinci bangaphandle yi-114mm, nangona kungekho mda uthile kubungakanani bombhobho kodwa kukho ubungakanani obukhethwayo obunikiweyo.
Kufuneka yenziwe ngemigangatho ehlalutyiweyo okanye yesakhiwo sentsimbi eshushu egoqwe ngokuhambelana ne-AS/NZS 1594 okanye i-AS/NZS 3678.
Ngokuxhomekeke ekusetyenzisweni kwayo ekugqibeleni, isahlulwe ngolu hlobo lulandelayo:
Imibhobho evavanywe ngamanzikufuneka yenziwe ngohlalutyo okanye ngomgangatho wesakhiwo sentsimbi egoqwe ngobushushu ehambelana ne-AS/NZS 1594 okanye i-AS/NZS 3678.
Iipayipu kunye nombhobho ongavavanywanga ngamanzikufuneka yenziwe ngentsimbi yodidi lwesakhiwo ehambelana ne-AS/NZS 1594 okanye i-AS/NZS 3678.
Okanye,iinqwabaingenziwa ngokwenqanaba lohlalutyo elihambelana ne-AS/NZS 1594., apho intsimbi kufuneka ivavanywe ngoomatshini ngokuhambelana ne-AS 1391 ukubonisa ukuba iyahlangabezana neemfuno zokuxinana ezichazwe ngumthengi.
Umbhobho wentsimbi we-AS 1579 wenziwa kusetyenziswaukuwelda nge-arc.
Zonke ii-welds mazibe zii-butt welds ezifakwe ngokupheleleyo.
Ukuwelda kwe-arc kusebenzisa ubushushu be-arc yombane ukunyibilikisa izinto zesinyithi nokwenza umdibaniso odibeneyo phakathi kweentsimbi ukwenza isakhiwo sombhobho wesinyithi oqhubekayo.
Inkqubo yokwenziwa kwe-arc welding esetyenziswa kakhulu yi-SAW (Suberged Arc Welding), ekwaziwa ngokuba yi-I-DSAW, ezinokwahlulwahlulwa zibeI-LSAW(SAWL) kunye ne-SSAW (I-HSAW) ngokwesikhokelo se-butt weld.
Ukongeza kwi-SAW, kukho ezinye iintlobo zokuwelda i-arc ezifana ne-GMAW, i-GTAW, i-FCAW, kunye ne-SMAW. Iindlela ezahlukeneyo zokuwelda i-arc zineempawu zazo kunye neemeko zokusetyenziswa, kwaye ukukhethwa kwendlela efanelekileyo yokuwelda kuxhomekeke kwiinkcukacha zombhobho wentsimbi oza kwenziwa, uhlahlo lwabiwo-mali, kunye neemfuno zomgangatho.
Imigangatho ngokwayo ayichazi ngokuthe ngqo ukwakheka kweekhemikhali ezithile kunye neempawu zoomatshini, njengoko oku kudla ngokuxhomekeka kwimigangatho ethile yentsimbi efana ne-AS/NZS 1594 okanye i-AS/NZS 3678, echaza ngokweenkcukacha iimfuno zekhemikhali kunye neempawu zoomatshini zentsimbi esetyenzisiweyo ukwenza ezi tyhubhu.
AS 1579 ichaza kuphela into elingana nekhabhoni.
I-carbon equivalent (CE) yentsimbi ayizukudlula i-0.40.
CE=Mn/6+(Cr+Mo+V)/5+(Ni+Cu)/15
I-CE yiparameter ebalulekileyo esetyenziselwa ukuvavanya ukudityaniswa kwentsimbi. Inceda ukuqikelela ukuqina okunokwenzeka kwintsimbi emva kokudityaniswa, ngaloo ndlela ihlole ukudityaniswa kwayo.
Uvavanyo loxinzelelo olusebenzisa amanzi amdaka luyafuneka kuyo yonke imibhobho yamanzi okanye yentsimbi esetyenziselwa ukuthutha.
Iipayipu azisoloko ziyimfuneko ukuba zivavanywe ngamanzi kuba zisetyenziselwa ukuthwala imithwalo yesakhiwo endaweni yoxinzelelo lwangaphakathi.
Imigaqo yovavanyo
Umbhobho uvalwe kwicala ngalinye kwaye ucinezelwe ngamanzi.
Ijongwa amandla kuxinzelelo olumele uxinzelelo loyilo lombhobho. Ivavanywa ukuqina kokuvuza kuxinzelelo olulinganisiweyo lombhobho.
Iingcinezelo zovavanyo
Uxinzelelo oluphezulu olulinganisiweyo lombhobho wentsimbi yi-6.8 MPa. Olu xinzelelo luphezulu lulawulwa ngumda wezixhobo zovavanyo loxinzelelo lwe-8.5 MPa.
Pr= 0.72×(2×SMYS×t)/OD okanye Pr= 0.72×(2×NMYS×t)/OD
Pr: Uxinzelelo olulinganisiweyo, kwi-MPa;
I-SMYS: Amandla amancinci okuvelisa achazwe kwi-MPa;
I-NMYS: Amandla amancinci okuvelisa isivuno, kwi-MPa;
tUbukhulu bodonga, nge-mm;
OD: Ububanzi obungaphandle, nge-mm.
Kwiimeko ezingxamisekileyo, uxinzelelo lwexeshana lunokukhokelela ekwandeni koxinzelelo lwemibhobho. Phantsi kwezi meko, uxinzelelo oludibeneyo oluphezulu oluvumelekileyo luya kugqitywa ngumyili, kodwa aluyi kudlula i-0.90 x SMYS.
Pt= 1.25Pr
Emva kovavanyo lwamandla, akuyi kubakho kuqhekeka okanye kuvuza kumbhobho wovavanyo.
I-90% yamandla amiselweyo e-minimum yield strength (SMYS) okanye amandla aqhelekileyo e-minimum yield strength (NMYS) okanye i-8.5 MPa, nokuba yeyiphi na engaphantsi.
Pl= Pr
Uvavanyo lokuvuza kufuneka lwenziwe kumbhobho.
Xa kuvavanywa ukuvuza, akuyi kubakho kuvuza okubonakalayo kumphezulu wombhobho.
Zonke iipayipi zovavanyo ezingezizo ezisebenzisa amanzi kufuneka zibe nobukhulu bodonga obungaphantsi kwe-8.0 mm.
UmbhobhoKuya kufuneka ukuba i-100% yee-welds zayo zivavanywe ngendlela engonakalisiyo ngeendlela ze-ultrasound okanye ze-radiographic ngokuhambelana ne-AS 1554.1 Category SP kwaye zihambelane nemigangatho yokwamkelwa echaziweyo.
Uvavanyo olungonakalisiyo lwee-welds ze-pile ezingaphelelangakwiinqwaba zemibhobhoIziphumo zovavanyo mazihambelane neemfuno ze-AS/NZS 1554.1 Class SP. Ukuba uhlolo lubonisa ukungathotyelwa kwelebheli, yonke i-weld kuloo mfumba yombhobho kufuneka ihlolwe.
Imibhobho kunye nezixhobo ezisetyenziselwa ukuhambisa amanzi kunye nelindle kufuneka zikhuselwe ekungcoleni ngokukhetha i-coating efanelekileyo. I-coating kufuneka isetyenziswe ngokuhambelana ne-AS 1281 kunye ne-AS 4321.
Kwimeko yamanzi asetyenziswa ekuseleni, kufuneka bathobele i-AS/NZS 4020. Injongo kukuqinisekisa ukuba ezi mveliso, xa zidibana nenkqubo yokubonelela ngamanzi, azichaphazeli kakubi umgangatho wamanzi, njengongcoliseko lwamakhemikhali, ungcoliseko lwe-microbiological, okanye utshintsho lwencasa kunye nenkangeleko yamanzi.
Umphezulu wangaphandle wetyhubhu, ongekho ngaphezulu kwe-150 mm ukusuka esiphelweni, kufuneka uphawulwe ngokucacileyo nangokusisigxina ngolu lwazi lulandelayo:
a) Inombolo ye-serial eyahlukileyo, oko kukuthi inombolo yetyhubhu;
b) Indawo yokwenziwa kwayo;
c) Ububanzi bangaphandle kunye nobukhulu bodonga;
d) Inombolo eqhelekileyo, oko kukuthi AS 1579;
e) Igama okanye uphawu lomenzi;
f) Uvavanyo lwe-hydrostatic test pressure rating (kuphela kumbhobho wentsimbi ovavanywe nge-hydrostatic);
g) Uphawu lovavanyo olungatshabalalisiyo (NDT) (kuphela kumbhobho wentsimbi oye wavavanywa ngendlela engatshabalalisiyo).
Umenzi kufuneka anike uMthengi isatifikethi esisayiniweyo esithi umbhobho wenziwe ngokuhambelana neemfuno zoMthengi kunye nalo Mgangatho.
I-ASTM A252: Yenzelwe iipayipu zentsimbi kwaye iqulethe iipropati ezineenkcukacha zoomatshini kunye neenkcukacha zokwakheka kweekhemikhali kwiindidi ezintathu zokusebenza.
EN 10219: inxulumene neetyhubhu zentsimbi ezakhiwe ngentsimbi ezidityanisiweyo ezenziwe ngokubandayo ukuze zisetyenziswe kwizakhiwo kuquka neenqwaba zeepayipi.
I-ISO 3183: Umbhobho wentsimbi olungiselelwe ishishini leoyile negesi, onemigangatho kunye namandla afunekayo okwenza ukuba ufanelekele ukuthwala iinqwaba zemibhobho.
I-API 5L: Isetyenziswa kakhulu kwiipayipi zothutho kwishishini leoyile negesi, imigangatho yomgangatho ophezulu ikwenza ukuba ifaneleke ukwenza iinqwaba ezithwalwa yimithwalo ephezulu.
I-CSA Z245.1: Ichaza imibhobho yentsimbi kunye nezixhobo zokuthutha ioyile negesi, ezikwafanelekile kwiinqwaba zemibhobho.
I-ASTM A690: Yenzelwe iipayipu zentsimbi ezisetyenziswa kwiindawo zaselwandle nakwezinye iindawo ezifanayo, nto leyo egxininisa ukuxhathisa ukugqwala.
I-JIS A 5525: Umbhobho wentsimbi ogqumayo oqhelekileyo waseJapan weenqwaba zemibhobho, kubandakanya izinto zokwakha, ukwenziwa, ubungakanani kunye neemfuno zokusebenza.
I-GOST 10704-91: Umbhobho wentsimbi ethe tye edityaniswe ngombane ukuze isetyenziswe kwizakhiwo nezakhiwo zobunjineli, kuquka neepayipu ezinde.
I-GOST 20295-85Iinkcukacha zeepayipi zentsimbi ezifakwe ngombane zokuthutha ioyile negesi, ezibonisa ukusebenza kwazo phantsi koxinzelelo oluphezulu nakwiindawo ezinzima, ezisebenza kwiinqwaba zeepayipi.
Ukususela oko yasekwa ngo-2014, iBotop Steel ibe ngumthengisi ophambili wemibhobho yentsimbi yekhabhoni eMntla China, eyaziwa ngenkonzo egqwesileyo, iimveliso ezikumgangatho ophezulu, kunye nezisombululo ezibanzi.
Le nkampani inikezela ngeendidi ngeendidi zeepayipi zentsimbi yekhabhoni kunye neemveliso ezinxulumene noko, kuquka ipayipi yentsimbi engenamthungo, i-ERW, i-LSAW, kunye ne-SSAW, kunye noluhlu olupheleleyo lwee-fittings zepayipi kunye nee-flanges.
Iimveliso zayo ezikhethekileyo ziquka ii-alloys zodidi oluphezulu kunye neentsimbi ezingenasici ze-austenitic, ezenzelwe ukuhlangabezana neemfuno zeeprojekthi ezahlukeneyo zemibhobho.
