API 5L X70 steel yeeb nkab yog hais txog qib hauv API (American Petroleum Institute) 5L tus qauv, uas yog siv rau cov kav dej steel kav. X70 steel muaj zog thiab corrosion kuj, feem ntau yog nyob rau hauv daim ntawv ntawm welded steel kav, thiab thaum lub sij hawm ua, nws yuav tsim ib tug nruab nrab phaj nrog tej yam specifications thiab ntau thiab tsawg, uas yuav siv tau ntxiv los ua ntau yam ntawm welded steel kav.
Qee qhov sib npaug ntawm API 5L X70 steel muaj xws li:
1. ASTM A691 Qib 70 (American Society for Testing and Materials)
2. EN 10208-2 Qib L485MB (European Standard)
3. GB/T 9711 X70 (Suav teb chaws Standard)
4. CSA Z245.1 Qib 483 (Canadian Standards Association)
5. JIS G3126 Qib X70 (Japanese Industrial Standard)
6. AS 1163 Qib X70 (Australian Standard)
Specifications thiab kev siv ntawm API 5L X70 steel yeeb nkab:
Specifications: Lub zog ntawm X70 steel yog 70kpsi, uas yog qib high-qib pipeline steel.
Kev Siv: Feem ntau yog siv rau cov roj thiab cov kav dej, nrog kev sib txuas zoo thiab ua haujlwm rau HIC (hydrogen induced cracking) thiab SSC (sulfide stress corrosion cracking), uas tuaj yeem txuag tau cov nqi tsim kho 2.
API 5L X70 steel yeeb nkab tsim cov txheej txheem thiab cov kev kho cua sov muaj xws li qhov kub thiab txias, nruab nrab kub tempering thiab kub tempering:
Tsawg kub tempering (150-250 degrees): tswj siab hardness thiab hnav tsis kam, txo cov kev ntxhov siab sab hauv thiab brittleness.
Nruab nrab kub tempering (250-500 degrees): txhim kho cov khoom muaj zog thiab elastic txwv, haum rau cov khoom muaj zog.
Kub kub tempering (500-650 degrees): tau txais cov khoom zoo txhua yam, haum rau cov khoom tseem ceeb
API 5L X70 siab kub steel yeeb nkab
