### 1. Khoom faib: Seamless vs. Welded Steel Pipes
Cov kav hlau hlau tau muab faib ua ob pawg loj raws li lawv txoj kev tsim khoom: ** seamless steel kav ** thiab ** welded steel kav ** (tseem hu ua ERW lossis LSAW kav).
** Seamless Steel Yeeb Nkab ** yog tsim los ntawm cov khoom siv puag ncig steel. Lub billet yog rhuab, pierced, thiab ces dov los yog extruded los ua ib tug hollow raj yam tsis muaj vuam seam. Cov qauv monolithic no tshem tawm cov ntsiab lus tsis muaj zog, muab cov kav dej seamless superior txhua yam muaj zog thiab siab ua haujlwm. Cov kav dej seamless tuaj yeem muab faib ntxiv rau hauv cov kav dej kub - dov seamless kav, txias- cov kav dej, cov kav dej precision, thiab cov kav dej extruded.
** Welded Steel Pipes ** yog tsim los ntawm steel coils lossis daim hlau uas tau dov rau hauv cov duab tubular nrog cov npoo welded ua ke raws seam. Raws li txoj kev welding thiab seam configuration, welded kav muaj xws li:
>** ERW (Electric Resistance Vuam) kav ** - tsim txias thiab welded siv hluav taws xob tsis kam. High- zaus ERW muaj cov qauv zoo sib xws, cov phab ntsa tuab tuab, thiab cov nqi tsim khoom tsawg, ua rau lawv xaiv ntau tshaj plaws rau kev siv qis rau nruab nrab siab.
>
>** LSAW (Longitudinally Submerged Arc Welded) cov kav dej ** - nrog rau qhov ntev seam welded los ntawm submerged arc vuam, haum rau loj diameters.
>
>** SSAW (Spiral Submerged Arc Welded) cov kav dej ** - nrog cov kav hlau txuas txuas, feem ntau siv rau loj - txoj kab uas hla cov kav dej.
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### 2. Cov txheej txheem tsim khoom: Yuav ua li cas cov yeeb nkab steel ua
Kev nkag siab txog cov txheej txheem tsim khoom pab cov neeg yuav khoom ntsuas qhov zoo thiab tsim nyog rau cov ntawv thov tshwj xeeb.
** Seamless Pipe Manufacturing Txheej Txheem: **
Cov txheej txheem pib nrog cov khoom round billets. Lub billet yog rhuab mus rau kwv yees li 1200 degree, ces pierced los ntawm ib tug mandrel los tsim ib tug hollow plhaub. Lub plhaub yog ntxiv elongated thiab loj los ntawm ib tug series ntawm dov mills kom ua tau raws li qhov xav tau sab nraud txoj kab uas hla thiab phab ntsa thickness. Rau cov kab me me los yog nruj dua, kev kos duab txias yog siv los ua cov txheej txheem thib ob. Qhov tsis muaj vuam seam ua rau cov kav dej seamless zoo tagnrho rau siab -siab thiab siab- qhov kub thiab txias, vim tias tsis muaj cov ntsiab lus tsis muaj zog ntawm cov yeeb nkab lub cev.
** ERW Welded Yeeb Nkab Txheej Txheem: **
ERW kav pib nrog descaled kub- dov steel coils. Lub kauj yog txiav mus rau ib qho dav dav uas sib haum rau lub hom phiaj yeeb nkab txoj kab uas hla. Lub sawb hla dhau los ntawm kev ua cov yob uas maj mam khoov nws mus rau hauv cov duab cylindrical. Ob lub npoo yog ces rhuab thiab fused ua ke nyob rau hauv hluav taws xob kuj siab, tsim ib tug longitudinal weld seam. Online tsis yog -kev kuaj kev puas tsuaj (NDT) yog ua los tshuaj xyuas qhov zoo ntawm vuam 【3†L50-L…】.
** LSAW thiab SSAW Manufacturing Process:**
Rau cov kav loj - txoj kab uas hla (feem ntau yog 16 ntiv tes thiab siab dua), cov hlau phaj yog siv. Lub phaj yog thawj zaug beveled raws nws cov npoo, tom qab ntawd tsim ua "U" zoo, ua raws li "O" zoo li (tus txheej txheem "UOE"), thiab thaum kawg welded raws li longitudinal seam siv submerged arc vuam. Txoj kev no tsim cov kav dej uas muaj qhov tseeb qhov tseeb thiab kev ncaj ncees ntawm kev sib txuas.
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### 3. Cov qauv kev lag luam thiab cov ntaub ntawv qib sib npaug
Cov kav hlau steel yog tswj hwm los ntawm ntau lub thoob ntiaj teb cov qauv. Peb lub tshuab muaj zog tshaj plaws thoob ntiaj teb yog Asmeskas cov qauv (ASTM / API), European qauv (EN), thiab Suav teb chaws qauv (GB). Hauv qab no yog cov ntsiab lus ntawm cov qauv uas feem ntau thiab lawv cov qib sib npaug:
| **Application Category**|** ASTM / API (USA) **|**EN (Europe)**|**GB (Suav teb)**|**JIS (Nyiv)** |
| --- | --- | --- | --- | --- |
| Kev siv dav dav|A53 Gr.B|S235JR|Q235B|STK400 |
| Siab -siab seamless|A106 Gr.B|P265GH|20#|SIB 370 |
| Cov kua dej qis / nruab nrab|A53 Gr.B / API 5L Gr.B|S235JR / P235TR1|Q235B / 20#|SIB 370 |
| Siab hlab ntsha|A179 / A192|P235GH / P265GH|20G / 16MnDG|STB340 / STB410 |
| Qab zib kev pabcuam kav dej|API 5L X42-X70 (PSL2)|ISO 3183 (tau tshaj)|GB/T 9711 L245-L485|- |
| Alloy steel raj|A335 P11/P22/P91|EN 10216-2|12CrMoV / 15CrMoG|STPA |
Rau kev siv cov raj xa dej, API 5L yog tus qauv tseem ceeb, nrog qib B txog X100X120 npog ntau qib zog. Rau cov qauv thiab kev siv engineering, ASTM A53, ASTM A106, EN 10219, thiab GB / T 3091 yog cov qauv siv feem ntau.
