Landzelaka, Hangao TEHC (Seko Machinery) yi ta ya emahlweni yi ku yisa ku twisisa swiphiqo leswi nga humelelaka hi nkarhi wa endlelo ro welda naswona yi ta ku pfuna ku sivela na ku tlhantlha swiphiqo swo tano.
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Ku twisisa ka thermal cracking ngopfu ngopfu swiya hi xivumbeko xa ti khemikhali, nhlengeletano na matirhelo ya material. Ni ya olova ku endla ti melting point compounds tale hansi kumbe eutectic na thyaka rofana na S na P. Ku hambanisiwa ka boron na silicon swita hlohletela ku pandzeka ka mahiselo.
Weld seam yi olova ku endla xivumbeko xa corenar crystal xa coarse lexinga na directionality yo tiya, leswi pfunaka eka ku hambanisiwa ka thyaka leri nga na khombo na swiaki. Leswi swi hlohletela ku endliwa ka filimi ya mati ya intergranular leyi yaka emahlweni naswona swi antswisa ku twisisa ka ku pandzeka ka mahiselo. Loko welding yinga hisiki hindlela leyi fanaka, swa olova ku endla tensile stress leyikulu naku hlohletela ku tumbuluxiwa ka welding hot cracks.
Magoza yo sivela:
a. Ku lawula hi ku hetiseka leswi nga endzeni ka thyaka leri nga ni khombo s na p.
b. Lulamisa nhlengeletano ya weld metal. Xivumbeko xa dual-phase weld xina ku lwisana kahle na ku pandzeka. Xiphemu xa delta eka weld xinga antswisa mavele, ku herisa directionality ya single-phase austenite, ku hunguta ku hambanisiwa ka thyaka ro biha eka ndzilakano wa mavele, naswona xiphemu xa delta xinga n’okisela ngopfu S na P swinga hunguta matimba ya interfacial naku hlela ku tumbuluxiwa ka intergranular liquid film.
C. Lulamisa xivumbeko xa weld metal alloy. Hindlela leyi faneleke ku engetela nhlayo ya Mn, C, na N eka single-phase austenitic steel, naswona u engetela nhlayo yitsongo ya ti trace elements tofana na cerium, pickaxe, na tantalum (leswi swinga antswisaka xivumbeko xa weld naku basisa ndzilakano wa mavele), leswinga hunguta ku twisisa ka thermal cracking.
d. Mimpimo ya phurosese. Pfuxeta ku hisa ngopfu ka xidziva lexi n’okiweke leswaku kutava na ku endliwa ka ti crystals to tiya ta columnar. Tirhisa vuhlalu lebyintsongo bya ku hisa na vuhlalu lebyintsongo bya weld bya xiphemu xo tsemakanya. an . Xitirhisiwa xo tiyisisa arc xinga engeteriwa hi nkarhi wa welding ku hunguta ndzhawu ya molten pool, ku antswisa ndlela yo tirha ya welding gun, naku antswisa khwalithi ya welding.
Xikombiso, 25-20 austenitic steel yitala kuva na ku pandzeka ka mati. Swinga koteka ku hunguta hiku hetiseka nhlayo ya thyaka na vukulu bya mavele ya base material, ku amukela tindlela ta high-energy density welding, ku nghenisiwa ka kuhisa lokuntsongo xikan’we naku engetela mpimo wa ku kufumela ka mahlangano.
04 Embrittlement ya swihlanganisi leswi weldiweke .
Nsimbi leyi tiyeke ku hisa yifanele kutiyisisa leswaku pulasitiki ya ti welded joints tifanele ku sivela embrittlement ya mahiselo yale henhla; Ti steels ta mahiselo yale hansi ti laveka kuva tiri na toughness ya kahle ya low-temperature kuva ti sivela brittle fracture ya brittle ya mahiselo yale hansi ya welded joints.
05 Ku soholotiwa lokukulu ka ku welda .
Hikokwalaho ka thermal conductivity yale hansi xikan’we na expansion coefficient leyikulu, welding deformation yikulu, naswona ti clamps tinga tirhisiwa ku sivela deformation. Ndlela yo welda ya austenitic stainless steel na ku hlawuriwa ka switirhisiwa swo welda:
Austenitic stainless steel yinga welderiwa hi argon tungsten arc welding (TIG), molten argon arc welding (MIG), plasma argon arc welding (PAW) na submerged arc welding (SAW).
Austenitic stainless steel yina current yale hansi ya welding hikokwalaho ka melting point yale hansi, low thermal conductivity, na high electrical resistivity. Ti welds letintsongo nati beads tifanele kutirhisiwa ku hunguta nkarhi waku tshama ka mahiselo yale henhla, ku sivela ku khuluka ka carbide, ku hunguta ntshikelelo wa weld shrinkage, naku hunguta thermal crack sensitivity.
Xivumbeko xa swilo swo welda, ngopfu ngopfu CR na Ni alloying elements, swile henhla kutlula swa base material. Tirhisa switirhisiwa swo welda leswingana nhlayo leyintsongo (4-12%) ya ferrite ku tiyisisa ku tiya ka kahle ka ku pandzeka (ku pandzeka ko titimela, ku pandzeka loku hisaka, ku pandzeka ka ntshikelelo wa ntshikelelo) ka weld.
Loko xiphemu xa ferrite xinga pfumeleriwi kumbe ku tsandzeka eka weld, switirhisiwa swo welda swifanele kuva switirhisiwa swo welda leswingana Mo, MN na swin’wana swa alloy.
C, S, P, SI, na NB eka switirhisiwa swo welda swifanele kuva swiri ehansi hilaha swinga kotekaka hakona. NB yita vanga ti solidification cracks eka pure austenitic weld, kambe nhlayo yintsongo ya ferrite eka weld yinga papalatiwa hindlela leyinene.
Eka swivumbeko swa welding leswi lavaka ku tiyisisiwa kumbe ku hungutiwa ka ntshikelelo endzhaku ka ku welda, switirhisiwa swo welda leswi nga na NB hi ntolovelo swa tirhisiwa. Submerged arc welding yitirhisiwa ku welda middle plate, naswona ku lahlekeriwa hi ku hisa ka Cr na Ni swinga engeteriwa hiku cinca ka flux na ti alloy elements eka welding wire;
Hikokwalaho ka vuenti lebyikulu bya ku nghena, kufanele ku tekeriwa enhlokweni ku sivela ku humelela ka ku pandzeka loku hisaka exikarhi ka weld xikan’we naku hunguteka ka corrosion resistance eka ndzhawu leyi khumbekaka hi kuhisa. Kufanele ku nyikiwa nyingiso eka ku hlawula waya wo welda wo olova xikan’we na welding heat input leyintsongo. Wire yo welda yi lava ku va ehansi eka SI, S, na p.
Nhlayo ya ferrite eka weld ya stainless steel leyi nga hisiki a yi fanelanga ku tlula 5%. Eka austenitic stainless steel leyingana CR na Ni content leyikulu kutlula 20%, high Mn (6-8%) welding wire yifanele kutirhisiwa, naswona alkaline kumbe neutral flux yifanele kutirhisiwa tani hi flux ku sivela ku engeteriwa ka SI eka weld naku antswisa ku lwisana ka yona ka crack.
Flux yo hlawuleka ya austenitic stainless steel yina ku tlakuka kutsongo swinene ka SI, leswinga hundzisela alloy eka weld naku tlherisela eka ku lahlekeriwa hi ku hisiwa ka ti elements ta alloy ku fikelela swilaveko swa matirhelo ya weld na xivumbeko xa ti khemikhali.
