Lefapheng la boenjiniere ba liphaephe, li-flange, e le likarolo tsa bohlokoa tsa ho kopanya liphaephe, li na le mefuta e mengata ea mefuta le mesebetsi. Har'a tsona, li-flange tse cheselitsoeng ka butt li fetohile "lihlahisoa tsa linaleli" lits'ebetsong tsa lipeipi tsa indasteri ka lebaka la ts'ebetso ea tsona e ntle haholo le maemo a ts'ebeliso e pharaletseng.

Welding flange, eo hape e tsejoang e le flange e phahameng ea molala, e ikhetha ka hore molala o phahameng o molelele le o sekametseng o tloha sebakeng sa welding pakeng tsa flange le phala (joalokaha ho bontšitsoe setšoantšong sa schematic). Moqapi o bohlale oa molala ona o phahameng ha o ntlafatse feela ho tiea le matla a flange, empa hape o fokotsa ka katleho ho khaotsa ho imeloa kelellong, ho netefatsa botsitso le ho tiisoa ha flange libakeng tse phahameng tsa khatello, mocheso o phahameng kapa o tlaase. Moralo oa lesoba le ka hare o moholo hanyane ho feta bophara bo ka ntle ba phaephe, 'me o etsa hore ho be bonolo ho cheselletsa butt, ha seam se circumferential weld se pharalla ka hare le kantle ho flange, se matlafatsa ts'ebetso ea ho tiisa.

Ka lebaka la melemo ena ea moralo, li-flange tse cheselitsoeng ka butt li loketse ka ho khetheha lits'ebetso tsa lipeipi tse nang le khatello e phahameng, mocheso o phahameng kapa mocheso o tlase masimong a indasteri joalo ka petroleum, lik'hemik'hale le kaho ea likepe. E ka mamella ho fetoha ho matla ha khatello le mocheso, ho netefatsa ts'ebetso e tsitsitseng ea pipeline. Ho sa le joalo, li-flange tse cheselitsoeng ka butt li boetse li sebelisoa hangata liphaepheng bakeng sa ho tsamaisa mecha ea litaba e tukang, e phatlohang kapa e chefo, 'me ts'ebetso ea bona e tšepahalang ea ho tiisa e fana ka tiisetso e matla bakeng sa lipalangoang tse bolokehileng tsa mecha ea litaba.

Ho ea ka litekanyetso tsa tlhahiso, li-flange tse cheselitsoeng ka butt li tlameha ho lumellana le litlhoko tse thata tse kang JB4726-4728. Ho ea ka likhatello tse fapaneng tsa mabitso le lisebelisoa, limaraka tsa ho qhekella li tloha ho Sehlopha sa I ho ea ho Sehlopha sa III ho netefatsa ts'ebetso ea flange libakeng tse fapaneng tsa mosebetsi. Ho phaella moo, letsoapo le ka ntle la molala oa flange welded ha ea lokela ho feta 70 °. Lintlha tsena tsa moralo li thusa ho laola ka thata litekanyo tsa tekheniki nakong ea tlhahiso le lits'ebetso tsa welding, li sebelisa karolo le boleng ba flange ka botlalo.