Hydrogen-induced Cracking (HIC) Resistance
Jan 26, 2024
SMLS Yeeb Nkab Supplier-GNEE
Hydrogen Cracking Test yog ib qho kev ntsuam xyuas uas ntsuas qhov tawg ntawm cov hlau nyob rau hauv ntub hydrogen sulfide ib puag ncig vim hydrogen uptake los ntawm cov khoom siv corrosion.
Hauv kev lag luam roj thiab roj thiab kev lag luam petrochemical, yog tias cov roj carbon lossis cov hlau tsis tshua muaj hlau raug xaiv los siv rau hauv qhov chaw ntub dej H2S, ces cov hlau phaj tuaj yeem ua rau mob hnyav heev.
Lub mechanism ntawm qhov embrittlement yog tias H2S reacts corrosively nrog steel nto los tsim hydrogen, uas yog absorbed los ntawm cov hlau uas ua rau hydrogen embrittlement. Rau cov hlau tsis tshua muaj hlau, qhov kev puas tsuaj no tuaj yeem muab faib ua cov hauv qab no:
1) Hydrogen Induced Cracking (HIC). HIC tsis xav kom muaj kev ntxhov siab los tsim thiab nthuav tawm hauv cov hlau.
2) Sulfide Stress Cracking (SSC). SSC feem ntau tshwm sim nyob rau hauv cov cheeb tsam ntawm siab hardness, xws li weld aav.
3) Stress Oriented Hydrogen Induced Cracking (SOHIC). Qhov tseeb, SOHIC tuaj yeem suav tias yog qhov tshwm sim ntawm kev sib xyaw ua ke ntawm HIC thiab SSC.
(4) Hydrogen ncua kev tawg: ntim hauv cov txheej txheem vuam, cov khoom siv vuam hauv dej lossis roj hauv cov arc nyob rau hauv qhov kev txiav txim ntawm qhov kub thiab txias decomposition ntawm hydrogen, ib feem ntawm cov hydrogen no rau hauv cov hlau molten weld, thaum lub vuam txias. kom diffuse tawm ntawm qhov tsim ntawm ib qho chaw muaj zog siab thiab ua rau weld micro-cracks hauv qhov tshwm sim.
Cov khoom muaj feem xyuam: pipeline steel, siab nkoj steel phaj, flanges thiab fittings, roj pipelines, siab hlab ntsha, boilers, roj drilling rods, li qub, flanges, fittings, petrochemical fittings.
Standards koom nrog:
nace tm 0284-2016
NACE TM 0284-2011
GB/T 8650-2015
Cov qauv xav tau:
Cov yeeb nkab fittings: ntev ntawm φ＜20mm: 320mm tag nrho cov yeeb nkab seem, ntev ntawm 20mm＜φ Tsawg dua los yog sib npaug rau 110mm: 240mm tag nrho cov yeeb nkab seem, ntev ntawm φ＞110mm: 150mm tag nrho cov yeeb nkab seem.
Phaj: 150 * 100mm, thickness=thawj thickness ntawm phaj.
Bar: Length>310mm * φ30mm.
(Tiav flanges, cov kav dej, cov yeeb nkab fittings, thiab lwm yam. tsis txhob cuam tshuam qhov loj ntawm cov qauv thaiv) Cov qauv saum toj no yog cov qauv txiav uas tsis yog thermal txiav)
