Tsev > Xov xwm > Ntsiab lus
Vuam hom kev kawm uas siv rau hauv Pipelines thiab Refinery Piping contrasting
Mar 12, 2016

Thaum ib tug zoo li tus roj loj loj thiab roj plahaum xws li ib tug refinery kis tau thoob acres ntau thiab sawv cev rau cov lab nyiaj cuab yeej siv thiab infrastructure peev, ib tug saib tsis nyoo crude roj rau lub refinery rau txoj kev refining. Qhov no yog vim roj crude yog thauj los ntawm ib tug underground pipeline. Lub twj tso kua mis chaw nres tsheb yam twj roj rau lub pipeline tseem nyob deb ntawm cov refinery.

Tiamsis cov underground pipeline thiab cov aboveground refinery tau muaj rau ib lub hom phiaj. Nws muab cov roj refined thiab lwm yam tshuaj rau pej xeem. Lub pipeline no rau lawv thauj khoom ntoo roj crude thiab cov refinery uas yog rau refining crude cov roj.

Yog nws nthuav kom paub tias cov hom kev kawm welding rau cov lug complementary nkaus opposite to sib. Downhill vuam hom kev kawm los mus vuam pipeline whereas nce toj vuam siv rau vuam lub nruab piping refinery. Txawm tus vuam leb thiab soj ntsuam cov hau kev no sib txawv. Lub pipeline vuam yog tshuaj ntawm API 1104 whereas refinery piping ua hauj lwm yog tshuaj los ntawm ASME Sec IX.

Nyob rau cov tshooj no peb mus tham ib los ntawm ib tug li cas thiab vim li cas tus ob welding kev txawv dua lwm. Nram qab no yog cov ntsiab chaw nrhiav qhov twg peb feem coob qhov txawv: 1.) weld qij, 2.) siv clamps, 3.) vuam txheej txheem, 4.) lis dej num thiab cov qauv qhia ntawv, 5.) electrode txheej, thiab 6.) vuam ceev.

Weld Joint

Cov yeeb nkab thickness cia siv rau hauv pipeline no feem ntau tshaj uas siv hauv refinery piping thiab cov yeeb nkab hnub ntawm ib lub pipeline yog tshuab beveled whereas yeeb nkab hnub ntawm ib pob qij refinery piping manually muab txiav thiab beveled. Tej yam zoo li ob tug ua si ib tug txiav txim qhov opposite welding rua kev loj.

Vim cov yeeb nkab tag ib pipeline yeeb yog Hoobkas machined thiab du, nws yog ib qho yooj yim mus use ib lub clamp rau ob hnub ntawm ib tug pipeline txha ua kom cov hauv paus hniav yam kis tsis muaj tacks, yog li downhill vuam pom (daim duab 1) tau kho yog zoo xaiv rau vuam hais. Nyob zoo ib, tus refinery piping, tsis zoo xwb cov yeeb nkab thickness ib yam tiam sis kuj cov xuas tes ua bevels tsis du ces. Tack welds yeej tseem siv siv clamps thiab cov cag kis no tsis yog yam xws li tom rooj plaub ntawm lub pob qij pipeline. Vim li no qhov nce toj vuam pom (daim duab 2) yog xaiv zoo.

Ib tshaj mas yog lub hauv paus kis ntawm pipeline thiab piping weld pob qij txha luaj li cas. Cag kis rau pipeline ob leeg yog 1.6 hli (daim duab 3) as compared to 3 hli rau piping weld rau ob leeg (daim duab 4). Se ua ke nrog ib cag kis me me thiab yuav muab tau yooj yim welded nrog pom downhill, fusing ob lub hauv paus ib sab, whereas loj khoob cag koj xav weaving suab ntawm cov electrode los fuse ob cag sab.

Kev siv cov Clamps
Cross-Country pipelines uas yuav kis tau rau cov mais uas welded spot. Contrast, cog piping pob qij txha npaj thiab welded nyob hauv ib Rhiav. Weld tau nrauj rau ob leeg noj kom koj lub tsev no tau.

Ib lub clamp (daim duab 5) yog siv nyob rau hauv cov pob qij pipeline rau cov kawm tuab si lug hais thiab yuav raug tshem tawm ntawm ob kawg ntawm cov yeeb nkab thaum lub hauv paus thiab yog cov uas kub yog tag. Whereas, vim tsis ntev thiab bent lengths ntawm piping pob qij txha muaj fittings, cov pob qej txha weld tau muab npaj nrog los sis tsis siv lwm clamps.

Lwm qhov txawv yog siv cov tacks. Nyob pipeline pob qij txha, tsis tacks siv ua lub hauv paus thiab yog cov uas kub tiav tam sim ntawd thaum lub sab hauv clamp qhov chaw whereas tus cog piping, weld tacks los npaj pob qij txha weld rau weld thaum ib theem tom ntej.

Txheej txheem vuam

Raws li tau piav lawm raws li yog vim li cas cov pipelines muaj welded los siv tus txheej txheem downhill thiab piping nrog rau tus txheej txheem nce toj, hauv tus txheej txheem downhill ob welders weld ib txha tuag saum ib txhij rau hauv qab ntawm cov yeeb nkab tom sab opposite whereas rau lub piping leeg txoj hauj lwm, kws cam hlau ib tub num tsoom sau tus tseem txha ntawm qab vuam rau saum ib tug piping txha.

Lis dej num thiab cov qauv

Raws li teev lawm, tus pipeline vuam yam txoj API 1104 code thiab cog vuam ntawm ASME Sec IX.

Rau ib pipeline, tus kws cam hlau xeem daim xa tuaj rau ib tug txhawb (daim duab 7) whereas lub xeem thooj ntawm ib tug kws cam hlau cog piping no tsuas muaj nyob rau hauv ib cov 45-kawm ntawv txoj hauj lwm (daim duab 8). Qhov no yog vim pipeline welds yuav ua ib tug txhawb thiab piping welds yog kwv hauv kab rov tav, ntsug thiab ntawm lub kaum ntse ntse 45-kawm ntawv txaus qhia.

Daim coupon kuaj tug no kuj txawv rau cov hom kev kawm li hauv daim duab 9 thiab daim duab 10.

Txheej electrode
Rau downhill vuam, cov electrodes siv yog cellulose txheej whereas rau nce toj vuam siv rau lub hauv paus tshaj lub electrode no cellulose txheej thiab tas cov accomplished uas tsis tshua muaj hydrogen-coated electrodes. Vim li cas qhov no yog 1) rau pipeline phab ntsa thickness, uas yog feem tsawg tshaj 12.5 hli; (2) yooj yim raug tshem tawm ntawm slag; (3) vuam ceev, thiab 4) lub hlaws nyias ntawm ib cellulose electrode. Tag nrho cov no yog cov yuav tsum pipeline vuam whereas cog piping cov yeeb nkab thickness tseem ntau dua, yog li ntawd weaving suab ntawm tus electrode yuav tsum weld hnyav thickness piping pob qij txha. Rau cov hom phiaj no electrodes tsawg-hydrogen siv.

Vuam ceev

Lub xeem – tiam sis tsis tsawg tshaj li – qhov sib txawv ntawm pipeline thiab cog piping vuam loj yog cov welding ntau lawm ceev. Ntawm no yog tej yam no sib txawv hauv vuam ceev:

1. piping pob qij txha yog tom thiab tacked nyob hauv ib Rhiav thiab feem ntau kws cam hlau ib sau tus txha tseem, vuam cag, sau thiab yog cov uas muab cov nqi. Whereas rau cross-country pipeline, tus qij yog tom nrog ib lub clamp rau lub site thiab vuam yam los ntawm ib pab cag ob feem coob tshaj welders, welders kis ob tug kub, ob tug sau ntawd kom tau welders thiab welders kis ob tug capping.

Leej welders ua vuam hauv map ntawm ib tug pipeline txha thiab cov neeg coob welding txav hauv lub caravan qhib pa. Vim li ntawd, vuam ntau lawm ceev yog ntau ntau dua piping pob qij txha welded hauv ib Rhiav.

2. qab ke vuam cov txheej txheem yuav zoo vuam ntau lawm hauv ib pipeline twg yeeb thickness no feem coob yog 12 lub hli los tsis muaj, whereas piping pob qij txha tseem ntau dua thickness thiab cov nce toj vuam cov txheej txheem yuav tsum tau sij hawm ntxiv; yog li, welding zus yog tsawg as compared to lub pipeline.

3. lwm kom sai vuam speeds nyob pipelines mas yog qhov electrode no toj mus rau nram qab thiab uas tsis muaj suab weaving. Whereas lub electrode tsiv tawm ntawm qab rau saum ib tug piping txha thiab cov nws muaj tus electrode slows tus welding ceev.

Sau
Engr. hu ua M. Younas Malik
yog ib pab mechanical kws ua choj los ntawm lub tsev kawm ntawv ntawm yam xws li tshuab thiab Technology, Lahore, Pakistan, thiab nrog rau ib tug kawm ntawv B.S. rau kawm lub tsev kawm ntawv polytechnic tsim los ntawm lub tsev kawm ntawv lub xeev Oklahoma hauv Rawalpindi, Pakistan. Nws nws kuj yog ib tug American vuam haiv neeg (AWS) thiab The American Society of Mechanical Engineers teb chaws USA.