1. ** Dab tsi yog Astm A790? **
ASTM A790 / A790M yog tus qauv kev paub tseeb los ntawm Astm International. Nws npog seamless thiab welded ferritic / austenitic / duplex) stainless hlau yeeb nkab kev pabcuam thiab kev siv kub siab. Cov kav dej no tau paub rau lawv lub zog siab thiab ua tau zoo heev rau kev ntxhov siab corrosion cracking thiab pitting / Crevice corrosion.
2. ** Dab tsi yog cov lus sib xyaw ntawm Astm A790? **
Cov muaj pes tsawg leeg ntawm Astm A790 cov yeeb nkab yeeb nkab txawv nyob ntawm qhov tshwj xeeb (Unified Numbering System) Qib Teev. Cov qib kawm feem ntau suav nrog S31803, S32205, S32750, S32760, thiab lwm tus. Feem ntau, cov duplex stainless hlau muaj:
* Chromium (CR): Feem ntau 20-29% (muab corrosion tsis kam)
* Npib tsib xee (NI): Feem ntau 4-8% (txhawb nqa Austenite theem, AIDS Toughness / Corrosion)
* Molybdenum (MO): Feem ntau 2-4.5% (Txhim Kho PITTING / Crevice Corrosion Kuj)
* Nitrogen (n): feem ntau 0.1-0.3% (ruaj khov Austenite, txhawb kev corrosion tsis kam)
* Manganese (mn): feem ntau <2.0%
* Silicon (si): feem ntau <1.0%
* Carbon (c): qis, feem ntau <0.030%
* Hlau (FE): Tshuav
* Qee qib (zoo li S32760) kuj muaj tungsten (w) thiab tooj (CU) rau kev txhim kho corrosion. Qhov tseeb chemical composition txwv yog nruj me ntsis txhais nyob rau hauv tus qauv rau txhua qib tsis txawv.
3. ** Cov khoom siv twg yog Astm A790 unu s32750? **
ASTM A790 UNRENS S32750 hais txog cov yeeb nkab tsim los ntawm ** Super Duplex stainless hlau muaj kwv yees li 25%, 4% molybdenum, thiab 0.25% nitrogen. Cov qib no muaj ntau lub zog, zoo heev tiv taus chloride kev ntxhov siab corrosion, thiab zoo nkauj pittings tsis kam (nrog tus pren> 40). Nws tau siv nyob rau hauv kev thov ib puag ncig zoo li ntug roj offshore roj & roj, tshuaj lom neeg, thiab dej hiav txwv.
4. ** Dab tsi yog ASTM A790 unu s32760 khoom? **
ASTM A790 UNS S32760 refers to pipe made from **Super Duplex Stainless Steel** grade commonly known as Zeron 100. Its typical composition includes approximately 25% Chromium, 7% Nickel, 3.5% Molybdenum, 0.7% Tungsten, 0.5% Copper, and 0.25% Nitrogen. The addition of Tungsten and Copper further enhances its corrosion resistance, particularly in very aggressive conditions like hot, sour brines in oil & gas production. It also has a very high PREN (>40) thiab lub zog.
5. ** Dab tsi yog qhov sib txawv ntawm Astm A790 thiab A789? **
ASTM A790 thiab AVETM A789 yog cov qauv sib txuam zoo nkauj, ob qho tib si npog seamless thiab werritic ferritic / Ausenitic (Duplex) tubrog stainless hlau. Lub ntsiab lus sib txawv yog cov khoom ** hom khoom ** Lawv tswj hwm:
* ** ASTM A789 / A789M: ** Daim Npog ** Seamless thiab Welded Ferritic / Ausenitic Stainless Hlau * HlAIV. Cov raj feem ntau cuam tshuam nrog cov diameters me me thiab siv zog kom nruj dua, feem ntau siv rau kev hloov pauv cua sov, cov hws, ntsuas kab, thiab cov ntawv thov txhua yam.
* ** ASTM A790 / A790M: ** DAIM NTAWV XEEM ** VERDED FERRRITICS / AUSTENITIC Stainless Hlau * kav dej ***. Cov kav dej feem ntau cuam tshuam nrog cov kab hniav ntau dua thiab feem ntau siv rau kev thauj khoom hauv cov roj av (piv txwv li cov raj xa khoom, pipelines).
Qhov tseem ceeb, ** Cov cuab yeej siv tshuaj lom neeg cov kev cai thiab cov khoom lag luam tub xws li hauv qab (a72750, thiab lwm yam) lossis "cov yeeb nkab" (A790) raws li nws cov yam ntxwv npaj thiab cov yam ntxwv.
