API 5CT L80 - Casing/Tubing for Sour Service
API 5CT L80yog ib qho nruab nrab -lub zog casing thiab tubing qib tshwj xeeb tsim los rauKev pabcuam qaub (H₂S ib puag ncig). Lub "L" keeb kwm hais txog "Line pipe" thiab "80" txhais tau tiasTsawg tshaj tawm lub zog ntawm 80,000 psi.
Cov yam ntxwv tseem ceeb
| Feature | Kev piav qhia |
|---|---|
| Khoom siv | Carbon-Manganese hlau nrogtswj hardness |
| Kev siv thawj zaug | Lub qhov dej ua kua qaub(H₂S tam sim no) |
| Cov khoom tseem ceeb | Sulfide Stress Cracking (SSC) tsis kam |
| Kev kho cua sov | Quenched & Tempered (yuav tsum tau) |
Mechanical Properties
| Khoom | Kev xav tau |
|---|---|
| Yield zog | 552-655 MPa (80-95 ksi) |
| Tensile zog, min | 655 MPa (95 ksi) |
| Hardness, max | 23 HRC (Rockwell C)- Qhov tseem ceeb rau kev pabcuam qaub |
Chemical Requirements (Controlled)
API 5CT qhiaqhov siab tshaj plawsrau qee cov ntsiab lus kom ntseeg tau tias SSC tsis kam:
| Element | Qhov siab tshaj (%) |
|---|---|
| Cov pa roj carbon (C) | 0.43 |
| Manganese (Mn) | 1.90 |
| Phosphorus (P) | 0.030 |
| Sulfur (S) | 0.030 |
Vim li cas L80 rau Sour Service?
Hardness Control:Qhov siab tshaj plaws23 HRCRaws li NACE MR0175 / ISO 15156 tus qauv.
Quenched & Tempered:Muab cov qauv microstructure zoo ib yam rau SSC tsis kam.
Tswj Chemistry:Lim txwv impurities uas ua phem rau cracking susceptibility.
Daim ntawv thov
Production casing/tubinghauv qhov dej nrog H₂S.
Intermediate casingnyob rau hauv corrosive formations.
Kev ntseeg siab thiab nqi -kev xaiv zoo raume me mus rau nruab nrab qaubib puag ncig.
Hom L80
L80-1:Standard Hom 1.
L80-9Cr:9% Chromium alloy rauTxhim kho CO₂ corrosion kuj.
L80-13Cr:13% Chromium alloy (zoo ib yam li 420 stainless) rauCO₂ corrosion hnyav dua.
Sib piv nrog N80
| Qib | Yield zog (ksi) | Sour Service? | Qhov txawv tseem ceeb |
|---|---|---|---|
| N80 | 80-110 | TSIS MUAJ | Siab zog, tsis muaj hardness tswj. |
| L80 | 80-95 | YOG | Tsawg zog max, hardness capped ntawm 23 HRC. |
Txoj Cai Yooj Yim:Rau qhov dejnrogH₂S → SivL80. Rau qhov dejtsis muajH₂S → SivN80(muaj zog thiab pheej yig dua).
Ordering Piv txwv
API 5CT L80 Casing, 7" 23#, Range 3, BTC. Hardness Tsawg dua los yog sib npaug rau 23 HRC.
Hauv cov ntsiab lus:API 5CT L80 yog tus qauvmus- mus rau qib txheemrau cov ntawv thov kev pabcuam qaub, muab pov thawj qhov sib npaug ntawm lub zog, SSC tsis kam, thiab tus nqi. Nws yuav tsum tau tswj hardness yog tus yuam sij rau nws txoj kev ntseeg siab nyob rau hauv corrosive qhov dej.
