A333Gr6 cryogenic hlab yog seamless steel raj tsim rau cov ntawv thov cryogenic, ua raws li ASTM A333 / ASME SA333 cov qauv. Lawv feem ntau yog siv rau hauv cov khoom siv petrochemical (xws li reactors, heat exchangers, and separators), natural gas processing, and cryogenic equipment manufacturing in environments range from -45℃to -195℃. Cov kev qhia tshwj xeeb muaj xws li sab nraud ntawm 21.3-762mm thiab phab ntsa tuab ntawm 2.0-140mm. Lawv tau tsim los siv kub dov, kos duab txias, lossis cov txheej txheem nthuav dav kub thiab xav tau kev kho cua sov ntawm 900℃~ 930℃thaum xa khoom.
Material Properties thiab Chemical Composition
1. Kev tsim qauv tsim
Gr.6 siv qhov qis- carbon steel puag (C Tsawg dua lossis sib npaug li 0.30%), ua tiav qis- qhov kub thiab txias los ntawm Ni-Cr-Mo composite microalloying. Tej yam compositions yog:
- C: 0.19%-0.25%
- Mn: 0.70% -1.05%
- Si: 0.15% - 0.35%
- Ni: 0.40% - 0.70%
Qhov sib ntxiv ntawm npib tsib xee refines lub grain loj thiab txo cov ductile - nkig hloov pauv kub, thaum txwv phosphorus thiab sulfur cov ntsiab lus (ob qho tib si tsawg dua los yog sib npaug rau 0.025%) txo qhov kev pheej hmoo ntawm impurity segregation.
2. Mechanical Properties
- Tensile zog Ntau dua lossis sib npaug li 415 MPa, Lub zog tawm los Ntau dua lossis sib npaug li 240 MPa
- Elongation Ntau dua lossis sib npaug li 22% (xws li cov yas deformation muaj peev xwm)
- Hardness Tsawg dua los yog sib npaug rau 197 HB (tsis txhob txias tawg thaum vuam)
Cov yam ntxwv ua haujlwm
Tsawg-Temperature Toughness: SA333Gr.6 seamless steel yeeb nkab muaj qhov zoo heev qis-kub toughness, haum rau qis- kub siab lub nkoj raj thiab qis-kub kub exchanger pipelines nyob rau hauv qhov kub ntawm -45℃rau -195℃.
Corrosion Resistance: Cov yeeb nkab steel no muaj kev tiv thaiv corrosion zoo txawm tias nyob rau hauv qhov chaw txias heev, tsis muaj pob txha tawg lossis lwm yam teeb meem.
Lub zog muaj zog thiab siab Toughness: Cov khoom muaj zog feem ntau tuaj yeem ncav cuag ntau dua 200 MPa, thiab lub zog tensile tuaj yeem ncav cuag ntau dua 400 MPa, ua tau raws li cov ntawv thov hauv ntau qhov chaw nyuaj.
Cov ntsiab lus tseem ceeb hauv kev tsim khoom
1. Cov txheej txheem smelting: Ib qho hluav taws xob arc rauv + LF refining ob - theem txheej txheem tau txais, tswj cov pa oxygen kom tsawg dua lossis sib npaug li 30 ppm, ua ke nrog kev kho calcium los txhim kho sulfide morphology. Ib lub tuam txhab ua lag luam hauv tsev tau txo cov ntsiab lus hydrogen kom qis dua 1.5 ppm los ntawm lub tshuab nqus tsev degassing (VD), txo qis qhov chaw dawb.
2. Kub ua haujlwm Technology
- Kub dov kub ntau yam: 900℃-1200℃; Thaum kawg dov kub: Ntau dua lossis sib npaug li 850℃kom tsis txhob sib xyaw nplej.
- Kev kho li qub (890℃± 10 degree) optimizes grain loj rau qib 7 lossis siab dua.
- ACC (Accelerated Accelerated Cooling) txheej txheem txhim kho qis -kub toughness; ib rooj plaub tau pom tias muaj 30% nce hauv kev cuam tshuam lub zog ntawm -60 degree.
3. Vuam Ntsiab Lus
Cov khoom siv vuam pom zoo: AWS A5.28 ER80S-Ni1; preheating kub: 100℃- 150 degree; interpass kub: Tsawg dua los yog sib npaug rau 200 degree. Kev saib xyuas tshwj xeeb yuav tsum tau them rau kev kho tom qab vuam hydrogen tshem tawm (250℃× 2h) txhawm rau tiv thaiv kev tawg qeeb.