API 5L PSL1 Qib X70 Ob Chav -Sided Submerged Arc Vuam (DSAW) Hlau Yeeb Nkab
Lub ntsiab lus tseem ceeb
API 5L PSL1 Qib X70 DSAW (Ob chav-Sided Submerged Arc Vuam) steel yeeb nkabyog lub siab -lub zog, micro- cov kab sib txuas cov yeeb nkab uas tsim los rau American Petroleum Institute specification rau cov kav dej thauj mus los. Qhov kev xaiv "X70" qhia txog qhov tsawg kawg nkaus tawm lub zog ntawm70,000 psi (483 MPa), sawv cev rau qib hwm ntawm qib siab - cov khoom siv kav dej muaj zog .
X70 yog tus hwm qib siab - qib zog muab kwv yees li8% siab tshaj tawm lub zog tshaj X65(483 MPa vs . 448 MPa),17% siab dua X60(483 MPa vs . 414 MPa), thiab35% siab dua X52(483 MPa vs . 359 MPa). Nws feem ntau tau teev tseg rau ntev -qhov deb siab siab- siab kis tau tus mob, cov kav dej tawm sab nrauv, thiab cov kev pabcuam arctic qhov twg lub zog siab tshaj plaws - rau - qhov hnyav piv yog qhov tseem ceeb.
Txoj kev tsim khoom DSAW-tseem hu ua LSAW (Longitudinal Submerged Arc Vuam)- yog qhov siab - vuam txoj kev ncaj ncees uas siv ob sab hauv thiab sab nraud welds, tsim ib qhoib leeg siab -zoo weld nugget. Cov txheej txheem no yog tsim tshwj xeeb rauloj- txoj kab uas hla, tuab- phab ntsa kavsiv nyob rau hauv siab - cov roj thiab roj xa mus, cov kav dej tawm sab nrauv, thiab kev siv cov txheej txheem.
Lub npe piav qhia
| Ib feem | Lub ntsiab lus |
|---|---|
| API | Lub koom haum American Petroleum |
| 5L | Specification rau kab yeeb nkab siv nyob rau hauv pipeline tsheb thauj mus los systems |
| PSL1 | Product Specification Level 1 – standard quality level with basic requirements (tsis muaj qhov yuav tsum tau muaj kev ntsuam xyuas) |
| X70 | Qib kev xaiv: "X" qhia qib pipeline, "70" sawv cev rau qhov tsawg kawg nkaus yield zog hauv ksi (70,000 psi / 483 MPa) |
| DSAW | Muab ob npaug rau-Sided Submerged Arc Vuam - ob qho tib si sab hauv thiab sab nraud yog siv; Lub vuam arc yog submerged hauv granular flux thaum vuam |
| Kuj Paub Raws li | LSAW (Longitudinal Submerged Arc Vuam) - thaum lub vuam seam khiav longitudinally raws cov yeeb nkab |
Ntsiab Specifications
| Yam ntxwv | Kev piav qhia |
|---|---|
| Txuj | API 5L (46th Edition, ua raws li ISO 3183) |
| Khoom Specification Level | PSL1 - tus qauv zoo |
| Qib | X70 (L485 hauv ISO cim) |
| Yam tsawg kawg nkaus Yield Strength | 483-485 MPa (70,000-70,300 psi) |
| Yam tsawg kawg Tensile Strength | 565-570 MPa (82,000-82,700 psi) |
| Kev tsim khoom | DSAW (Ob chav -Sided Submerged Arc Vuam) / LSAW (Longitudinal Submerged Arc Vuam) |
| Txoj kev tsim | JCOE(progressive J-C-O forming) los yogUAE(U-ing, O-ing, Expanding) |
| Size Range (DSAW/LSAW) | 406mm txog 1829mm(16 "mus rau 72") OD - raug rau DSAW; mus txog 84 "muaj |
| Phab ntsa Thickness | 6.0mm txog 50mm (txog 75mm rau kev siv tshwj xeeb) |
| Ntev | 6 m rau 12 m txheem; mus txog 18 m muaj |
| Xaus Xaus | Plain xaus, beveled xaus (30℃bevel kaum sab xis) |
| Txheej txheej xaiv | Dub xim, kua roj vanish, anti- xeb roj, FBE, 3LPE, thee tar epoxy, CWC |
Tshuaj muaj pes tsawg leeg (API 5L PSL1 Qib X70 Welded Yeeb Nkab)
Raws li API 5L PSL1 qhov yuav tsum tau ua rau welded yeeb nkab:
| Element | Ntau tshaj % | Sau ntawv |
|---|---|---|
| Cov pa roj carbon (C) | 0.26% | Tsawg carbon rau zoo weldability |
| Manganese (Mn) | 1.65% | Siab dua qib qis rau lub zog |
| Phosphorus (P) | 0.030% | Tswj rau weldability |
| Sulfur (S) | 0.030% | Tswj kom toughness |
| Silicon (Si) | Tsis tau teev rau PSL1 | Feem ntau Tsawg dua lossis sib npaug rau 0.45% |
| Vanadium (V) | Raws li pom zoo | Micro-Alloying rau cov nplej refinement |
| Niobium (Nb) | Raws li pom zoo | Micro{0}} alloying rau lub zog |
| Titanium (Ti) | Raws li pom zoo | Micro-Alloying rau cov nplej refinement |
Lus Cim: Rau txhua qhov kev txo qis ntawm 0.01% qis dua cov ntsiab lus siab tshaj plaws ntawm cov pa roj carbon monoxide, qhov nce ntawm 0.05% saum toj no qhov siab tshaj plaws manganese tau tso cai. PSL1 tsis muaj qhov yuav tsum tau ua rau lub zog siab tshaj plaws, qhov sib npaug ntawm cov pa roj carbon monoxide, lossis qhov yuav tsum tau ntsuas qhov cuam tshuam.
Mechanical Properties (API 5L PSL1 Qib X70)
| Khoom | Kev xav tau |
|---|---|
| Yield zog (min) | 483-485 MPa (70,000-70,300 psi) |
| Yield zog (max) | Tsis tau teev rau PSL1 |
| Tensile zog (min) | 565-570 MPa (82,000-82,700 psi) |
| Tensile zog (max) | Tsis tau teev rau PSL1 |
| Weld Tensile zog (min) | Ntau dua lossis sib npaug rau 570 MPa (82,700 psi) |
| Elongation | Ib tus qauv API 5L (vim los ntawm phab ntsa thickness) |
| Charpy Impact | Tsis xav tau rau PSL1- Tsuas yog PSL2 yuav tsum tau kuaj qhov cuam tshuam |
| Yield-rau-Tensile Ratio | Tsis tau teev rau PSL1 |
X70 vs. Qhov sib piv ntawm Qib Kawm
| Qib | Yield zog (min) | Tensile zog (min) | Tus txheeb ze zog vs. X70 | Daim ntawv thov |
|---|---|---|---|---|
| X52 | 359 MPa (52 ksi) | 455 MPa (66 ksi) | -26% | General kis tau tus mob |
| X56 | 386 MPa (56 ksi) | 490 MPa (71 ksi) | -20% | Siab dua -siab kis |
| X60 | 414 MPa (60 ksi) | 517 MPa (75 ksi) | -14% | High -siab kis |
| X65 | 448 MPa (65 ksi) | 531 MPa (77 ksi) | -7% | Siab -siab, offshore |
| X70 | 483 MPa (70 ksi) | 565 MPa (82 ksi) | Lub hauv paus | Ntev -qhov deb siab -siab, offshore, arctic |
| X80 | 552 MPa (80 ksi) | 621 MPa (90 ksi) | +14% | Ultra-siab- siab lub cev kab |
X70 muaj kwv yees li 8% siab dua qhov muaj zog tshaj X65, 17% siab dua X60, thiab 35% siab dua X52 .
Dimensional Specifications
| Parameter | Ntau Yam / Tolerance |
|---|---|
| Sab nraud txoj kab uas hla | 406mm txog 1829mm(16 "mus rau 72") - DSAW ntau yam; mus txog 84 "muaj |
| Phab ntsa Thickness | 6.0mm txog 50mm (txog 75mm rau kev siv tshwj xeeb) |
| Txoj kab uas hla Tolerance (Lub cev yeeb nkab) | ± 0.75% ntawm OD |
| Txoj kab uas hla (Cov yeeb nkab kawg, D Tsawg dua lossis sib npaug rau 168.3mm) | -0.4 hli rau +1.6 hli |
| Txoj kab uas hla (Cov yeeb nkab kawg, 168.3mm |
± 0.005D, max ± 1.6 hli |
| Txoj kab uas hla (Cov yeeb nkab kawg, 610mm |
± 1.6 hli |
| Phab ntsa Thickness kam rau ua (t Tsawg dua lossis sib npaug li 5 hli) | ± 0.5 hli |
| Phab ntsa Thickness kam rau ua (5mm |
±0.1t |
| Phab ntsa Thickness kam rau ua (t Ntau dua lossis sib npaug li 15mm) | ± 1.5 hli |
| Ntev | 6 m rau 12 m txheem; mus txog 18 m muaj |
| Tawm ntawm - ntawm - Roundness | Tsawg dua lossis sib npaug li 1% ntawm OD teev |
Yam Loj Muaj (API 5L Qib X70 DSAW):
| OD (inch) | OD (mm) | Phab ntsa Thickness Range (mm) |
|---|---|---|
| 16" | 406 | 6.0 - 14.0 |
| 20" | 508 | 6.0 - 16.0 |
| 24" | 610 | 6.0 - 18.0 |
| 30" | 762 | 7.0 - 21.0 |
| 36" | 914 | 8.0 - 24.0 |
| 40" | 1016 | 8.0 - 26.0 |
| 48" | 1219 | 9.0 - 28.0 |
| 56" | 1422 | 10.0 - 29.0 |
| 60" | 1524 | 10.0 - 29.0 |
| 64" | 1626 | 10.0 - 30.0 |
| 72" | 1829 | 10.0 - 30.0 |
DSAW/LSAW Manufacturing Process
Ob chav -Sided Submerged Arc Vuam (DSAW), tseem hu ua Longitudinal Submerged Arc Vuam (LSAW), yog ib qho kev ua haujlwm siab - siv feem ntau rau cov kav loj - txoj kab uas hla.
Txheej txheem piav qhia
Vuam arc yog submerged hauv granular fluxThaum vuam, tiv thaiv cov vuam los ntawm atmospheric paug
Ob sab hauv thiab sab nraud welds yuav tsum tau, feem ntau ua tiav hauv cov txheej txheem sib cais
Cov sib cais welds noj ib feem ntawm lwm yam, ua rau aib leeg siab -zoo weld nugget
Txoj kev tsim
| Txoj kev | Kev piav qhia | Hom kab |
|---|---|---|
| JCOE | Progressive J-C-O cov kauj ruam (J-shape → C-shape → O-shape), nthuav dav tom qab vuam | 406-1626 hli (16 "-64") |
| UAE | Phaj nias rau hauv U-puab, ces O-puab, nthuav dav tom qab vuam | 508-1118 hli (20 "-44") |
Txheej txheem txheej txheem
Phaj xaiv- Hlau daim hlau ntsib API 5L PSL1 X70 yuav tsum
Ntug Kev Npaj- Ntug yog beveled los tsim V-puab zawj
tsim- Cov ntawv hlau yog tsim rau hauv cov duab cylindrical siv JCOE lossis UOE presses
Tack Vuam- Cov phaj tsim yog tack-welded kom zoo li qub
Ob chav Submerged Arc Vuam- Cov yeeb nkab seam welded rau ob sab hauv thiab sab nrauv
Txias Expansion- Cov yeeb nkab yuav raug nthuav mus txog 1.5% kom ua tiav qhov kawg ntawm OD
Ultrasonic soj ntsuam- Seam tshuaj xyuas los ntawm kev txuas ntxiv ultrasonic tsis siv neeg qhov tsis pom kev
Hydrostatic Pressure Test-Txhua cov yeeb nkab tau kuaj xyuas hydrostatic siab (thaum teev tseg)
Ua tiav- Xaus kev, beveling, txheej, thiab kos npe raws li specifications
Kev Ntsuas & Kev Ntsuam Xyuas (PSL1)
| Hom kev xeem | Kev xav tau | Sau ntawv |
|---|---|---|
| Tshuaj ntsuam xyuas | Rau qhov kub ntau | Txheeb xyuas qhov txwv tsis pub muaj ib qho API 5L PSL1 |
| Tensile Test | Rau ntau | Txheeb xyuas qhov tawm los thiab lub zog tensile |
| Flattening Test | Yuav tsum tau | Txheeb xyuas qhov ductility thiab weld kev ncaj ncees |
| Khoov Test | Yuav tsum tau | Verifies weld kev ncaj ncees |
| Charpy Impact Test | Tsis xav tau rau PSL1 | Tsuas yog PSL2 yuav tsum tau kuaj qhov cuam tshuam |
| Hydrostatic Test | Txhua yeeb nkab (thaum teev) | Kev ntsuas siab ncaj ncees |
| Ultrasonic soj ntsuam | 100% ntawm weld seam | Standard xyaum rau DSAW |
| X-Ray Inspection | Rau "T" pob qij txha | Qhov twg strip taub qab welds cuam tshuam kauv seams |
| Dimensional soj ntsuam | 100% | Raws li tus qauv tolerances |
| Mill Test Certificate | EN 10204 Hom 3.1B | Muab tag nrho cov kev xeem |
PSL1 vs. PSL2 Sib piv rau X70
| Feature | PSL 1 X 70 | PSL 2 X 70 | Qhov tseem ceeb |
|---|---|---|---|
| Cov pa roj carbon (C) max | 0.26% | 0.12-0.24% | PSL2 muaj kev tswj nruj dua kom zoo dua weldability |
| Sulfur (S) max | 0.030% | 0.015% | PSL2 muaj 50% txo qis - qhov tseem ceeb rau kev toughness |
| Phosphorus (P) max | 0.030% | 0.025% | PSL2 muaj kev txwv nruj dua |
| Manganese (Mn) max | 1.65% | 1.65-1.85% | Siab dua rau lub zog |
| Yield zog | 483 MPa min xwb | 483-635 MPa ntau | PSL2 qhia txog qhov siab tshaj plaws los tiv thaiv ntau tshaj - cov ntaub ntawv muaj zog |
| Tensile zog | 570 MPa min xwb | 565-760 MPa ntau | PSL2 qhia qhov siab tshaj plaws rau qhov sib xws |
| Yield-rau-Tensile Ratio | Tsis tau teev tseg | Tsawg dua lossis sib npaug li 0.93 | PSL2 xyuas kom txaus ductility |
| Kev ntsuam xyuas cuam tshuam | Tsis xav tau | Yuav tsum tau | PSL2 lav qis-kub toughness |
| Carbon sib npaug | Tsis xav tau | Muab xam thiab tswj | PSL2 xyuas kom zoo teb weldability |
| NDT Requirements | Txuj | nruj dua | PSL2 muab kev kuaj pom zoo dua |
| Traceability | Batch qib | Pipe -los ntawm- yeeb nkab puv traceability | PSL2 muaj cov ntaub ntawv ua tiav zoo |
| Hom kev siv | Kev pabcuam dav dav, kab dej, tsis yog - tseem ceeb | Kev pabcuam tseem ceeb, kev pabcuam qaub, qis kub |
Cov ntawv thov siv
| Daim ntawv thov | Kev piav qhia |
|---|---|
| Ntev-Nyob deb siab-Npaj roj xa mus | Cov kab loj hauv lub cev xav tau kev ua haujlwm siab |
| Offshore thiab Subsea Pipelines | Subsea pipelines xav tau lub zog siab - rau - qhov hnyav piv |
| Arctic thiab Cold Climate Pipelines | Tsawg- qhov kub thiab txias ib puag ncig yuav tsum muaj siab toughness |
| Crude Roj Trunk Kab | Cov kab txuas tseem ceeb rau kev thauj cov roj av |
| Onshore Gathering Networks | Regional trunk systems txuas cov chaw tsim khoom rau kev ua haujlwm |
| Chaw nres tsheb thiab Header Piping | Compressor chaw nres tsheb, twj tso kua mis, metering chaw |
| Kev xa dej | Loj - txoj kab uas hla, siab - siab dej mains |
| Muaj Txheej Txheem Piping | Refineries, tshuaj nroj tsuag, tsim hluav taws xob |
Qhov Zoo Tshaj Plaws
| Qhov zoo | Kev piav qhia |
|---|---|
| Siab zog | 70,000 psi tawm los - 8% siab dua X65, 17% siab dua X60, 35% siab dua X52 |
| Tus nqi -Cov | PSL1 yog qhov kev lag luam ntau dua li PSL2 - haum rau cov ntawv thov kev pabcuam dav dav uas tsis tas yuav tsum muaj qhov kub thiab txias |
| Weldability zoo heev | Cov ntsiab lus tsis tshua muaj cov pa roj carbon monoxide ua kom muaj kev sib tw zoo |
| Loj Loj Muaj peev xwm | DSAW tsim cov kav dej ntawm 16 "mus rau 72" OD - zoo tagnrho rau cov ntawv loj - txoj kab uas hla |
| High Weld Integrity | Muab ob npaug rau- sab vuam tsim ib qho siab - zoo weld nugget nrog 100% UT tshuaj xyuas |
| Dav Muaj | Feem ntau stocked los ntawm manufacturers thoob ntiaj teb |
| JCOE/UOE tsim | Precise dimensional precision los ntawm kev tsim cov txheej txheem siab heev |
| Pov thawj Performance | Dav siv dav hauv siab -pas kis tau tus mob, cov kav dej tawm ntug dej hiav txwv, thiab cov ntawv thov xav tau |
International Approximations
| Txuj | Qib sib npaug | Sau ntawv |
|---|---|---|
| TS EN ISO 3183 | L485 | International txheem sib npaug |
| GB/T 9711 | L485 | Suav sib npaug |
| TS EN 10208-2 | L485 MB | European sib npaug |
| TIAB SA 17172 | TSI 480.7 TM | Keeb kwm German sib npaug |
Txheej txheej xaiv
API 5L PSL1 X70 DSAW yeeb nkab tuaj yeem muab nrog ntau txheej txheej rau kev tiv thaiv corrosion:
| Txheej hom | Zoo tshaj rau | Ntsiab nta |
|---|---|---|
| 3LPE (3-txheej polyethylene) | Cov kav dej faus | Feem ntau; zoo heev tiv thaiv corrosion, siab cuam tshuam kuj |
| FBE (Fusion Bonded Epoxy) | Roj & roj pipelines | Muaj zog adhesion, tshuaj tiv thaiv |
| Coal Tar Epoxy | Marine ib puag ncig | Heavy-lub luag haujlwm tiv thaiv |
| CWC (Concrete Weight Txheej) | Offshore / subsea pipelines | Tsis zoo buoyancy thiab mechanical tiv thaiv |
| Varnish / Anti- xeb roj | Kev tiv thaiv ib ntus | Luv -lub sij hawm tiv thaiv corrosion thaum thauj |
| Bitumen txheej | Kev pabcuam faus | Tus nqi -kev tiv thaiv zoo |
| Dub Roj Txheej | Standard zeb tiav | Kev tiv thaiv ib ntus |
Xaus Xaus
Muaj cov kev kho mob kawg suav nrog:
Plain xaus (PE)- txheem rau ntau daim ntawv thov
Beveled xaus (BE)- rau qhov chaw vuam (30℃bevel kaum sab xis)
Xov xaus- rau kev sib txuas tshuab
Kev txiav txim siab tseem ceeb
1. PSL1 vs. PSL2 Xaiv
PSL1: Haum rau cov kev pabcuam dav dav, cov kab dej, tsis yog - daim ntawv thov tseem ceeb uas tsis muaj qhov ntsuas kub tsawg - tsis tas yuav tsum muaj qhov toughness
PSL2: Yuav tsum muaj rau qis- kev pabcuam kub (qis dua 0 degree), kev pabcuam qaub (H₂S ib puag ncig), cov kav dej tswj (FERC, DOT), thiab cov ntawv thov tseem ceeb
2. X70 vs. Qeb / Qib Siab
X52: General kis tau tus mob (52 ksi tawm los)
X56: Siab dua -siab kis tau tus mob (56 ksi tawm los)
X60: Siab -siab kis tau tus mob (60 ksi tawm los)
X65: Siab -siab, offshore (65 ksi tawm los)
X70: Ntev -qhov deb siab -siab, offshore, arctic(70 ksi yield)
X80: Ultra-siab- cov kab hauv siab (80 ksi tawm los)
3. DSAW Cov Kev Cai Loj
DSAW manufacturing rau X70 feem ntau muaj los ntawm16" to 72" OD
Cov kab me me (hauv qab 16 ") feem ntau yog tsim los ntawm ERW los yog seamless txoj kev
4. Kev sim cuam tshuam
PSL1 uatsis yogxav tau Charpy qhov kev ntsuam xyuas los ntawm tus qauv. Yog tias qhov ntsuas kub tsawg - qhov kev pabcuam kub tau npaj tseg, xav txog:
Txheeb xyuas qhov cuam tshuam raws li qhov yuav tsum tau ua ntxiv
Hloov kho dua tshiab rau PSL2 (uas tso cai rau kev sim cuam tshuam)
5. Kev txwv kub
Qhov siab tshaj plaws qhov kev pab cuam qhov kub thiab txias:350℃(662℃F)
Tsis muaj kev lees paub qis -kub toughness nyob rau hauv PSL1 - tsis haum rau sub-zero daim ntawv thov yam tsis muaj kev ntsuam xyuas
6. Thib peb-Kev soj ntsuam tog
Muaj cov kev pabcuam tshuaj xyuas suav nrog SGS, BV, Lloyds
7. Mill Test Certificate
Feem ntau muab raws liEN 10204 Hom 3.1Bnrog tag nrho cov kev xeem
Thib peb-kev tshuaj ntsuam xyuas muaj nyob rau thaum thov
8. Weldability
Cov ntsiab lus carbon tsawg (tsawg dua lossis sib npaug li 0.26%) ua kom muaj kev sib txuas zoo heev
Haum rau txhua txoj kev vuam txheej txheem (SMAW, GTAW, GMAW, SAW)
Tsis muaj kev tshaj tawm -weld cua sov yuav tsum tau kho rau feem ntau thicknesses
Rau cov ntawv thov kev pabcuam qaub nrog PSL2, yuav tsum muaj kev coj ua qis hydrogen
Cov ntsiab lus
API 5L PSL1 Qib X70 Ob Chav -Sided Submerged Arc Welded (DSAW/LSAW) steel yeeb nkabyog tus hwm qib siab - zog kab yeeb nkab rau kev thov ntev -qhov deb siab- cov ntawv thov kev sib kis. Nrog yam tsawg kawg nkaus tawm lub zog ntawm70,000 psi (483 MPa)- kwv yees li8% siab dua X65, 17% siab dua X60, thiab35% siab dua X52- thiab tensile lub zog ntawm82,000 psi (565 MPa), cov khoom siv no yog qhov kev xaiv zoo tshaj plaws rau siab - cov kav xa hluav taws xob siab, kev siv sab nrauv, kev pabcuam hauv Arctic, thiab cov kev xav tau uas cov qib qis yuav xav tau cov phab ntsa tuab heev.
Cov yam ntxwv tseem ceeb:
Khoom txheem: API 5L PSL1 X70 - siab- qib zog rau kev pabcuam dav dav
Yield zog483 MPa (70,000 psi) yam tsawg kawg nkaus - 8% siab dua X65, 17% siab dua X60
Tensile zog565 MPa (82,000 psi) yam tsawg kawg nkaus
PSL1 qib zoo: Tsis muaj qhov yuav tsum tau kuaj xyuas; cov qauv kev cai rau kev pabcuam dav dav
DSAW manufacturingtsim cov kav dej los ntawm16" to 72" ODnrog phab ntsa thickness mus txog50 mm
Ob -sab vuamtsim ib lub siab -zoo weld nugget
JCOE los yog UOE tsimcov txheej txheem kom paub meej qhov tseeb qhov tseeb
100% ultrasonic kuajntawm weld seam kom zoo
Weldability zoo heevnrog cov ntsiab lus carbon tsawg (tsawg dua lossis sib npaug li 0.26%)
Tus nqi- zoo- kev xaiv pheej yig tshaj plaws rau siab -siab loj- kab yeeb nkab
Cov ntawv thov uas muaj xws li:
Ntev -qhov deb siab- cov kav xa hluav taws xob siab
Offshore thiab subsea pipelines
Arctic thiab txias huab cua pipelines
Crude roj trunk kab
Chaw nres tsheb thiab header piping
Kev xa dej mains
Industrial txheej txheem kav
Thaum ordering, qhia:API 5L PSL1 Qib X70, DSAW/LSAW (Ob chav-Sided/Longitudinal Submerged Arc Welded), Loj (OD x WT), Ntev, Qhov Kawg Finish (plain/beveled), Cov Lus Qhia Txheej Txheem, thiab Daim Ntawv Pov Thawj Zeb rau EN 10204 Hom 3.1B
Rau cov ntawv thov uas xav tau kev lees paub qis -kub toughness, nruj chemistry tswj, lossis qaub muaj peev xwm ua haujlwm, qhia meejAPI 5L PSL2 Qib X70hloov. Rau feem ntau siab - cov ntawv thov kev sib kis, X70 PSL1 muaj qhov sib npaug zoo ntawm lub zog thiab kev lag luam.
