{"id":1322,"date":"2025-11-17T12:34:36","date_gmt":"2025-11-17T05:34:36","guid":{"rendered":"https:\/\/inoxcuongthinh.com\/bon-chua-hoa-chat-an-mon-chon-inox-316l-hay-904l-va-cach-thiet-ke\/"},"modified":"2025-11-17T12:34:36","modified_gmt":"2025-11-17T05:34:36","slug":"bon-chua-hoa-chat-an-mon-chon-inox-316l-hay-904l-va-cach-thiet-ke","status":"publish","type":"post","link":"https:\/\/inoxcuongthinh.com\/bon-chua-hoa-chat-an-mon-chon-inox-316l-hay-904l-va-cach-thiet-ke\/","title":{"rendered":"B\u1ed3n ch\u1ee9a h\u00f3a ch\u1ea5t \u0103n m\u00f2n: ch\u1ecdn inox 316L hay 904L v\u00e0 c\u00e1ch thi\u1ebft k\u1ebf"},"content":{"rendered":"<div class=\"custom-toc\">\n<h3>N\u1ed9i dung ch\u00ednh<\/h3>\n<ul>\n<li><a href=\"#toc-0-316l-va-904l-khac-nhau-o-dau-va-y-nghia-voi-bon-ho\">316L v\u00e0 904L: kh\u00e1c nhau \u1edf \u0111\u00e2u v\u00e0 \u00fd ngh\u0129a v\u1edbi b\u1ed3n h\u00f3a ch\u1ea5t?<\/a><\/li>\n<li><a href=\"#toc-1-nguyen-tac-chon-vat-lieu-theo-moi-chat-nong-do-nhi\">Nguy\u00ean t\u1eafc ch\u1ecdn v\u1eadt li\u1ec7u theo m\u00f4i ch\u1ea5t, n\u1ed3ng \u0111\u1ed9, nhi\u1ec7t \u0111\u1ed9<\/a><\/li>\n<li><a href=\"#toc-2-cac-gioi-han-thuc-hanh-quan-trong-voi-cl-va-nhiet-\">C\u00e1c gi\u1edbi h\u1ea1n th\u1ef1c h\u00e0nh quan tr\u1ecdng v\u1edbi Cl- v\u00e0 nhi\u1ec7t \u0111\u1ed9<\/a><\/li>\n<li><a href=\"#toc-3-tieu-chuan-va-thong-so-thiet-ke-bon-inox\">Ti\u00eau chu\u1ea9n v\u00e0 th\u00f4ng s\u1ed1 thi\u1ebft k\u1ebf b\u1ed3n inox<\/a><\/li>\n<li><a href=\"#toc-4-thiet-ke-chong-an-mon-chi-tiet-quan-trong-thuong-b\">Thi\u1ebft k\u1ebf ch\u1ed1ng \u0103n m\u00f2n: chi ti\u1ebft quan tr\u1ecdng th\u01b0\u1eddng b\u1ecf s\u00f3t<\/a><\/li>\n<li><a href=\"#toc-5-kiem-soat-chat-luong-va-nghiem-thu\">Ki\u1ec3m so\u00e1t ch\u1ea5t l\u01b0\u1ee3ng v\u00e0 nghi\u1ec7m thu<\/a><\/li>\n<li><a href=\"#toc-6-bai-toan-chi-phi-va-nguon-cung-tai-viet-nam\">B\u00e0i to\u00e1n chi ph\u00ed v\u00e0 ngu\u1ed3n cung t\u1ea1i Vi\u1ec7t Nam<\/a><\/li>\n<li><a href=\"#toc-7-quy-trinh-6-buoc-chon-nhanh-316l-hay-904l\">Quy tr\u00ecnh 6 b\u01b0\u1edbc ch\u1ecdn nhanh 316L hay 904L<\/a><\/li>\n<li><a href=\"#toc-8-vi-du-thuc-te-tai-viet-nam\">V\u00ed d\u1ee5 th\u1ef1c t\u1ebf t\u1ea1i Vi\u1ec7t Nam<\/a><\/li>\n<li><a href=\"#toc-9-nguon-tham-khao-ky-thuat\">Ngu\u1ed3n tham kh\u1ea3o k\u1ef9 thu\u1eadt<\/a><\/li>\n<li><a href=\"#toc-10-ket-luan\">K\u1ebft lu\u1eadn<\/a><\/li>\n<\/ul>\n<\/div>\n<p>Trong c\u00f4ng nghi\u1ec7p h\u00f3a ch\u1ea5t \u2013 m\u1ed9t m\u0169i nh\u1ecdn c\u1ee7a \u201cInox trong C\u00f4ng nghi\u1ec7p N\u1eb7ng\u201d, l\u1ef1a ch\u1ecdn \u0111\u00fang m\u00e1c inox v\u00e0 thi\u1ebft k\u1ebf chu\u1ea9n ngay t\u1eeb \u0111\u1ea7u quy\u1ebft \u0111\u1ecbnh tu\u1ed5i th\u1ecd v\u00e0 an to\u00e0n c\u1ee7a b\u1ed3n ch\u1ee9a. B\u00e0i vi\u1ebft n\u00e0y \u0111i th\u1eb3ng v\u00e0o c\u00e2u h\u1ecfi: khi n\u00e0o ch\u1ecdn inox 316L, khi n\u00e0o c\u1ea7n l\u00ean 904L, v\u00e0 ph\u1ea3i thi\u1ebft k\u1ebf \u2013 ch\u1ebf t\u1ea1o th\u1ebf n\u00e0o \u0111\u1ec3 b\u1ed3n ch\u1ecbu \u0111\u01b0\u1ee3c m\u00f4i tr\u01b0\u1eddng \u0103n m\u00f2n th\u1ef1c t\u1ebf t\u1ea1i Vi\u1ec7t Nam.<\/p>\n<h2 id=\"toc-0-316l-va-904l-khac-nhau-o-dau-va-y-nghia-voi-bon-ho\">316L v\u00e0 904L: kh\u00e1c nhau \u1edf \u0111\u00e2u v\u00e0 \u00fd ngh\u0129a v\u1edbi b\u1ed3n h\u00f3a ch\u1ea5t?<\/h2>\n<p>&#8211; 316L (UNS S31603, 1.4404): 16.5\u201318.5% Cr, 10\u201314% Ni, 2\u20132.5% Mo, C \u22640.03%. \u01afu \u0111i\u1ec3m: ph\u1ed5 d\u1ee5ng, gi\u00e1 h\u1ee3p l\u00fd, ch\u1ed1ng r\u1ed7 t\u1ed1t h\u01a1n 304. H\u1ea1n ch\u1ebf: nh\u1ea1y c\u1ea3m pitting\/crevice trong Cl- cao, d\u1ec5 n\u1ee9t SCC Cl- >60\u00b0C, k\u00e9m trong HCl v\u00e0 H2SO4 trung b\u00ecnh \u2013 \u0111\u1eadm \u0111\u1eb7c. PREN \u2248 23\u201325.<br \/>\n&#8211; 904L (UNS N08904, 1.4539): 19\u201323% Cr, 23\u201328% Ni, 4\u20135% Mo, 1\u20132% Cu, C \u22640.02%. \u01afu \u0111i\u1ec3m: kh\u00e1ng pitting\/crevice v\u01b0\u1ee3t tr\u1ed9i, ch\u1ed1ng SCC t\u1ed1t, \u0111\u1eb7c bi\u1ec7t hi\u1ec7u qu\u1ea3 trong axit sunfuric v\u00e0 axit phosphoric c\u00f3 t\u1ea1p Cl-. H\u1ea1n ch\u1ebf: gi\u00e1 cao, ngu\u1ed3n h\u00e0ng c\u1ea7n \u0111\u1eb7t. PREN \u2248 35.<br \/>\n&#8211; \u00dd ngh\u0129a k\u1ef9 thu\u1eadt: PREN c\u00e0ng cao, kh\u1ea3 n\u0103ng ch\u1ed1ng r\u1ed7 v\u00e0 k\u1ebd h\u1edf c\u00e0ng t\u1ed1t; Ni v\u00e0 Cu cao c\u1ee7a 904L c\u1ea3i thi\u1ec7n \u0111\u00e1ng k\u1ec3 hi\u1ec7u n\u0103ng trong m\u00f4i tr\u01b0\u1eddng axit kh\u1eed (v\u00ed d\u1ee5 H2SO4). D\u1eef li\u1ec7u CPT \u0111i\u1ec3n h\u00ecnh: 316L ~10\u201320\u00b0C trong 3.5% NaCl; 904L ~35\u201350\u00b0C (Outokumpu Corrosion Handbook).<\/p>\n<h2 id=\"toc-1-nguyen-tac-chon-vat-lieu-theo-moi-chat-nong-do-nhi\">Nguy\u00ean t\u1eafc ch\u1ecdn v\u1eadt li\u1ec7u theo m\u00f4i ch\u1ea5t, n\u1ed3ng \u0111\u1ed9, nhi\u1ec7t \u0111\u1ed9<\/h2>\n<p>Ch\u1ecdn m\u00e1c inox d\u1ef1a tr\u00ean ba bi\u1ebfn ch\u00ednh: lo\u1ea1i h\u00f3a ch\u1ea5t, n\u1ed3ng \u0111\u1ed9, nhi\u1ec7t \u0111\u1ed9; c\u1ed9ng th\u00eam t\u1ea1p ch\u1ea5t (\u0111\u1eb7c bi\u1ec7t Cl-), tr\u1ea1ng th\u00e1i ch\u1ea3y\/r\u1ed7ng, v\u00e0 th\u1eddi gian l\u01b0u. D\u01b0\u1edbi \u0111\u00e2y l\u00e0 h\u01b0\u1edbng d\u1eabn th\u1ef1c h\u00e0nh d\u1ef1a tr\u00ean b\u1ea3ng t\u01b0\u01a1ng th\u00edch v\u1eadt li\u1ec7u c\u1ee7a c\u00e1c h\u00e3ng th\u00e9p kh\u00f4ng g\u1ec9 l\u1edbn v\u00e0 t\u1ed5 ch\u1ee9c chuy\u00ean ng\u00e0nh.<\/p>\n<h3>H2SO4 (axit sunfuric)<\/h3>\n<p>&#8211; 316L: ch\u1ec9 ph\u00f9 h\u1ee3p kho\u1ea3ng \u22645% \u1edf nhi\u1ec7t \u0111\u1ed9 m\u00f4i tr\u01b0\u1eddng; nhanh ch\u00f3ng b\u1ecb \u0103n m\u00f2n khi n\u1ed3ng \u0111\u1ed9\/ nhi\u1ec7t \u0111\u1ed9 t\u0103ng.<br \/>\n&#8211; 904L: \u0111\u01b0\u1ee3c ph\u00e1t tri\u1ec3n cho H2SO4; d\u00f9ng t\u1ed1t 0\u201335% \u1edf nhi\u1ec7t \u0111\u1ed9 m\u00f4i tr\u01b0\u1eddng, v\u00e0 90\u201398% \u1edf nhi\u1ec7t \u0111\u1ed9 m\u00f4i tr\u01b0\u1eddng. V\u00f9ng 35\u201370% nh\u1ea1y c\u1ea3m h\u01a1n; c\u1ea7n ki\u1ec3m so\u00e1t nhi\u1ec7t \u0111\u1ed9 th\u1ea5p v\u00e0 t\u1ea1p Cl- r\u1ea5t th\u1ea5p.<br \/>\n&#8211; Khuy\u1ebfn ngh\u1ecb: b\u1ed3n H2SO4 l\u01b0u kho \u1edf nhi\u1ec7t \u0111\u1ed9 m\u00f4i tr\u01b0\u1eddng n\u00ean d\u00f9ng 904L; n\u1ebfu >40\u00b0C ho\u1eb7c c\u00f3 Cl-, c\u00e2n nh\u1eafc v\u1eadt li\u1ec7u cao c\u1ea5p h\u01a1n ho\u1eb7c l\u00f3t phi kim.<br \/>\nNgu\u1ed3n: Outokumpu Corrosion Handbook; Nickel Institute.<\/p>\n<h3>HCl (axit clohydric)<\/h3>\n<p>&#8211; 316L v\u00e0 904L: kh\u00f4ng khuy\u1ebfn ngh\u1ecb \u1edf n\u1ed3ng \u0111\u1ed9 >0.5\u20131% k\u1ec3 c\u1ea3 nhi\u1ec7t \u0111\u1ed9 m\u00f4i tr\u01b0\u1eddng do \u0103n m\u00f2n \u0111i\u1ec3m v\u00e0 k\u1ebd h\u1edf r\u1ea5t m\u1ea1nh.<br \/>\n&#8211; Gi\u1ea3i ph\u00e1p: th\u00e9p l\u00f3t cao su\/FRP, h\u1ee3p kim Ni-Cu\/Cu-Ni \u0111\u1eb7c bi\u1ec7t, ho\u1eb7c Alloy 20\/Hastelloy t\u00f9y \u0111i\u1ec1u ki\u1ec7n.<br \/>\nNgu\u1ed3n: Nickel Institute Chemical Resistance.<\/p>\n<h3>H3PO4 (axit phosphoric)<\/h3>\n<p>&#8211; 316L: d\u00f9ng \u0111\u01b0\u1ee3c ~30\u201340% \u1edf nhi\u1ec7t \u0111\u1ed9 m\u00f4i tr\u01b0\u1eddng n\u1ebfu Cl- r\u1ea5t th\u1ea5p.<br \/>\n&#8211; 904L: d\u00f9ng t\u1ed1t \u0111\u1ebfn 85% v\u00e0 \u1edf nhi\u1ec7t \u0111\u1ed9 cao h\u01a1n; ch\u1ecbu Cl- v\u1ebft t\u1ed1t h\u01a1n.<br \/>\n&#8211; Khuy\u1ebfn ngh\u1ecb: ph\u00e2n b\u00f3n\/phosphate 85% c\u00f3 Cl- v\u1ebft \u2192 ch\u1ecdn 904L.<\/p>\n<h3>NaOH (x\u00fat)<\/h3>\n<p>&#8211; 316L: ph\u00f9 h\u1ee3p \u0111\u1ebfn 50% v\u00e0 80\u2013100\u00b0C; tr\u00e1nh nhi\u1ec5m Cl-.<br \/>\n&#8211; 904L: t\u1ed1t t\u01b0\u01a1ng \u0111\u01b0\u01a1ng; kh\u00f4ng c\u1ea7n thi\u1ebft n\u1ebfu ch\u1ec9 c\u00f3 x\u00fat s\u1ea1ch.<br \/>\n&#8211; Khuy\u1ebfn ngh\u1ecb: \u01b0u ti\u00ean 316L, tr\u1eeb khi c\u00f3 Cl- ho\u1eb7c t\u1ea1p oxy h\u00f3a.<\/p>\n<h3>NaOCl, Cl2, m\u00f4i tr\u01b0\u1eddng oxy h\u00f3a ch\u1ee9a clo<\/h3>\n<p>&#8211; 316L\/904L: kh\u00f4ng khuy\u1ebfn ngh\u1ecb cho NaOCl\/bleach; r\u1ee7i ro r\u1ed7 v\u00e0 SCC cao.<br \/>\n&#8211; Gi\u1ea3i ph\u00e1p: titan, FRP, ho\u1eb7c th\u00e9p carbon l\u00f3t.<br \/>\nNgu\u1ed3n: Outokumpu, NACE.<\/p>\n<h3>Axetic, axetic tr\u1ed9n<\/h3>\n<p>&#8211; 316L: t\u1ed1t \u1edf m\u1ecdi n\u1ed3ng \u0111\u1ed9 \u1edf nhi\u1ec7t \u0111\u1ed9 m\u00f4i tr\u01b0\u1eddng.<br \/>\n&#8211; 904L: th\u01b0\u1eddng kh\u00f4ng c\u1ea7n, tr\u1eeb khi c\u00f3 Cl- ho\u1eb7c nhi\u1ec7t \u0111\u1ed9 cao.<\/p>\n<h3>N\u01b0\u1edbc bi\u1ec3n, n\u01b0\u1edbc mu\u1ed1i<\/h3>\n<p>&#8211; 316L: d\u1ec5 r\u1ed7\/crevice trong n\u01b0\u1edbc bi\u1ec3n t\u0129nh >20\u00b0C.<br \/>\n&#8211; 904L: kh\u00e1 h\u01a1n, nh\u01b0ng v\u1eabn c\u00f3 r\u1ee7i ro trong n\u01b0\u1edbc bi\u1ec3n \u1ea5m v\u00e0 t\u00f9 \u0111\u1ecdng.<br \/>\n&#8211; Khuy\u1ebfn ngh\u1ecb: n\u1ebfu b\u1eaft bu\u1ed9c d\u00f9ng austenitic, 904L t\u1ed1t h\u01a1n 316L; song Duplex 2205\/6Mo \u0111\u00e1ng c\u00e2n nh\u1eafc.<\/p>\n<h2 id=\"toc-2-cac-gioi-han-thuc-hanh-quan-trong-voi-cl-va-nhiet-\">C\u00e1c gi\u1edbi h\u1ea1n th\u1ef1c h\u00e0nh quan tr\u1ecdng v\u1edbi Cl- v\u00e0 nhi\u1ec7t \u0111\u1ed9<\/h2>\n<p>&#8211; Pitting\/Crevice: ch\u1ecdn m\u00e1c c\u00f3 PREN ph\u00f9 h\u1ee3p v\u1edbi n\u1ed3ng \u0111\u1ed9 Cl- v\u00e0 nhi\u1ec7t \u0111\u1ed9. 316L an to\u00e0n khi Cl- th\u1ea5p v\u00e0 T th\u1ea5p; 904L ch\u1ecbu Cl- cao h\u01a1n v\u00e0 nhi\u1ec7t cao h\u01a1n.<br \/>\n&#8211; SCC clorua: 316L c\u00f3 nguy c\u01a1 cao >60\u00b0C trong dung d\u1ecbch c\u00f3 Cl-; 904L nh\u1edd h\u00e0m l\u01b0\u1ee3ng Ni cao kh\u00e1ng t\u1ed1t h\u01a1n, nh\u01b0ng kh\u00f4ng \u201cmi\u1ec5n d\u1ecbch\u201d.<br \/>\n&#8211; T\u1ea1p ch\u1ea5t: ch\u1ec9 v\u00e0i ch\u1ee5c ppm FeCl3 c\u0169ng c\u00f3 th\u1ec3 g\u00e2y r\u1ed7 c\u1ee5c b\u1ed9 tr\u00ean 316L; c\u1ea7n l\u1ecdc\/ki\u1ec3m so\u00e1t t\u1ea1p Cl-.<\/p>\n<p>Ngu\u1ed3n: ASTM G48 (th\u1eed nghi\u1ec7m pitting), Outokumpu Corrosion Handbook.<\/p>\n<h2 id=\"toc-3-tieu-chuan-va-thong-so-thiet-ke-bon-inox\">Ti\u00eau chu\u1ea9n v\u00e0 th\u00f4ng s\u1ed1 thi\u1ebft k\u1ebf b\u1ed3n inox<\/h2>\n<p>&#8211; Quy ph\u1ea1m:<br \/>\n  &#8211; B\u1ed3n \u00e1p l\u1ef1c: ASME Section VIII Div.1 (TC t\u01b0\u01a1ng \u0111\u01b0\u01a1ng TCVN ch\u1ea5p nh\u1eadn).<br \/>\n  &#8211; B\u1ed3n h\u00e0n ch\u1ee9a kh\u00f4ng \u00e1p: API 650 (c\u0169ng ph\u00f9 h\u1ee3p nhi\u1ec1u d\u1ecbch d\u1ecbch l\u1ecfng h\u00f3a ch\u1ea5t); API 620 cho b\u1ed3n \u00e1p su\u1ea5t th\u1ea5p\/nhi\u1ec7t \u0111\u1ed9 th\u1ea5p.<br \/>\n&#8211; V\u1eadt li\u1ec7u:<br \/>\n  &#8211; T\u1ea5m: ASTM A240 (316L\/904L).<br \/>\n  &#8211; \u1ed0ng: ASTM A312; m\u1eb7t b\u00edch: ASTM A182; ph\u1ee5 ki\u1ec7n: ASTM A403.<br \/>\n&#8211; Chi\u1ec1u d\u00e0y v\u00e0 d\u1ef1 ph\u00f2ng \u0103n m\u00f2n: v\u1edbi inox, corrosion allowance th\u01b0\u1eddng b\u1eb1ng 0 khi ki\u1ec3m so\u00e1t \u0111\u01b0\u1ee3c m\u00f4i tr\u01b0\u1eddng; n\u1ebfu c\u00f3 x\u00f3i m\u00f2n\/c\u1ecd r\u1eeda, th\u00eam 0.5\u20131.0 mm.<br \/>\n&#8211; \u1ee8ng su\u1ea5t cho ph\u00e9p: d\u00f9ng theo ASME II-D; 904L v\u00e0 316L kh\u00e1c bi\u1ec7t gi\u1edbi h\u1ea1n ch\u1ea3y kh\u00f4ng l\u1edbn \u0111\u1ed1i v\u1edbi t\u00ednh to\u00e1n d\u00e0y.<\/p>\n<h2 id=\"toc-4-thiet-ke-chong-an-mon-chi-tiet-quan-trong-thuong-b\">Thi\u1ebft k\u1ebf ch\u1ed1ng \u0103n m\u00f2n: chi ti\u1ebft quan tr\u1ecdng th\u01b0\u1eddng b\u1ecf s\u00f3t<\/h2>\n<p>&#8211; T\u1ed1i gi\u1ea3n k\u1ebd h\u1edf: tr\u00e1nh ch\u1ed3ng m\u00ed, d\u00f9ng h\u00e0n li\u00ean t\u1ee5c, n\u1eafp \u0111\u1eady l\u1eafp k\u00edn; crevice l\u00e0 \u0111i\u1ec3m kh\u1edfi ph\u00e1t r\u1ed7.<br \/>\n&#8211; B\u1ec1 m\u1eb7t: ho\u00e0n thi\u1ec7n m\u1ecbn (Ra \u22641.5 \u03bcm v\u1edbi h\u00f3a ch\u1ea5t s\u1ea1ch; \u22640.8 \u03bcm v\u1edbi d\u1ecbch \u0103n m\u00f2n\/Cl-), t\u1ea9y g\u1ec9 &#038; th\u1ee5 \u0111\u1ed9ng h\u00f3a theo ASTM A380\/A967.<br \/>\n&#8211; H\u00e0n:<br \/>\n  &#8211; 316L d\u00f9ng que\/ d\u00e2y ER\/E309L\/316L (chu\u1ea9n l\u00e0 316L).<br \/>\n  &#8211; 904L d\u00f9ng ER385 (904L).<br \/>\n  &#8211; Ki\u1ec3m so\u00e1t nhi\u1ec7t \u0111\u1ea7u v\u00e0o, nhi\u1ec7t \u0111\u1ed9 gi\u1eefa l\u1edbp; m\u1ee5c ti\u00eau ferrite v\u1eeba ph\u1ea3i \u0111\u1ec3 tr\u00e1nh n\u1ee9t n\u00f3ng nh\u01b0ng v\u1eabn b\u1ec1n \u0103n m\u00f2n.<br \/>\n  &#8211; Lo\u1ea1i b\u1ecf m\u00e0u nhi\u1ec7t sau h\u00e0n (heat tint) b\u1eb1ng pickling paste; kh\u00f4ng \u0111\u1ec3 m\u1ed1i h\u00e0n s\u1eabm m\u00e0u ti\u1ebfp x\u00fac m\u00f4i ch\u1ea5t.<br \/>\n&#8211; V\u1ec7 sinh: tr\u00e1nh nhi\u1ec5m s\u1eaft carbon (d\u1ee5ng c\u1ee5 m\u00e0i ri\u00eang cho inox), kh\u00f4ng d\u00f9ng b\u00e0n ch\u1ea3i th\u00e9p th\u01b0\u1eddng.<br \/>\n&#8211; Gio\u0103ng\/bulong: d\u00f9ng PTFE\/ePTFE; tr\u00e1nh gio\u0103ng cao su th\u00f4ng th\u01b0\u1eddng trong axit m\u1ea1nh. Bulong AISI B8M (316) cho ngo\u1ea1i vi kh\u00f4; c\u00e1ch ly galvani n\u1ebfu g\u1ea7n th\u00e9p carbon. D\u00f9ng m\u1ee1 ch\u1ed1ng d\u00ednh (anti-galling) cho ren inox.<br \/>\n&#8211; Th\u1eed k\u00edn\/hydrotest: d\u00f9ng n\u01b0\u1edbc \u00edt Cl- (<50 ppm); x\u1ea3 kh\u00f4 ngay, th\u1ed5i kh\u00f4, t\u00e1i th\u1ee5 \u0111\u1ed9ng h\u00f3a n\u1ebfu c\u1ea7n \u0111\u1ec3 tr\u00e1nh r\u1ed7 s\u1edbm.  \n- CUI (\u0103n m\u00f2n d\u01b0\u1edbi l\u1edbp c\u00e1ch nhi\u1ec7t): ch\u1ecdn v\u1eadt li\u1ec7u c\u00e1ch nhi\u1ec7t h\u00e0m l\u01b0\u1ee3ng Cl- th\u1ea5p, l\u1edbp \u00e1o ch\u1ed1ng \u1ea9m t\u1ed1t; tr\u00e1nh d\u1ea3i 60\u2013120\u00b0C k\u00e9o d\u00e0i v\u1edbi h\u01a1i \u1ea9m.\n\nNgu\u1ed3n: ASTM A380\/A967; API 650; Nickel Institute \u201cGuidelines for the welded fabrication of stainless steel\u201d.\n\n\n\n<h2 id=\"toc-5-kiem-soat-chat-luong-va-nghiem-thu\">Ki\u1ec3m so\u00e1t ch\u1ea5t l\u01b0\u1ee3ng v\u00e0 nghi\u1ec7m thu<\/h2>\n<p>&#8211; PMI (ki\u1ec3m tra x\u00e1c \u0111\u1ecbnh m\u00e1c) 100% cho v\u1eadt li\u1ec7u t\u1ea5m, \u1ed1ng, ph\u1ee5 ki\u1ec7n tr\u01b0\u1edbc khi gia c\u00f4ng.<br \/>\n&#8211; NDT m\u1ed1i h\u00e0n: PT (th\u1ea9m th\u1ea5u), MT (n\u1ebfu c\u00f3 ph\u1ea7n ferromagnetic), UT chi\u1ec1u d\u00e0y, RT theo r\u1ee7i ro.<br \/>\n&#8211; S\u1ed5 h\u00e0n WPS\/PQR theo ASME IX; th\u1ee3 h\u00e0n ch\u1ee9ng ch\u1ec9 GTAW\/SMAW cho inox.<br \/>\n&#8211; B\u00e1o c\u00e1o t\u1ea9y g\u1ec9 \u2013 th\u1ee5 \u0111\u1ed9ng h\u00f3a: h\u00f3a ch\u1ea5t, th\u1eddi gian, pH, \u0111\u1ed9 s\u1ea1ch b\u1ec1 m\u1eb7t.<\/p>\n<h2 id=\"toc-6-bai-toan-chi-phi-va-nguon-cung-tai-viet-nam\">B\u00e0i to\u00e1n chi ph\u00ed v\u00e0 ngu\u1ed3n cung t\u1ea1i Vi\u1ec7t Nam<\/h2>\n<p>&#8211; 316L: s\u1eb5n h\u00e0ng t\u1ea5m 2\u201325 mm, \u1ed1ng\/ph\u1ee5 ki\u1ec7n \u0111\u1ee7 c\u1ee1; gi\u00e1 h\u1ee3p l\u00fd, leadtime ng\u1eafn.<br \/>\n&#8211; 904L: th\u01b0\u1eddng ph\u1ea3i \u0111\u1eb7t; gi\u00e1 g\u1ea5p ~2.5\u20134 l\u1ea7n 316L t\u00f9y th\u1eddi \u0111i\u1ec3m th\u1ecb tr\u01b0\u1eddng; leadtime 4\u201312 tu\u1ea7n.<br \/>\n&#8211; Chi\u1ebfn l\u01b0\u1ee3c t\u1ed1i \u01b0u: d\u00f9ng 904L \u201c\u0111\u00fang ch\u1ed7\u201d (v\u00f9ng \u01b0\u1edbt, ph\u1ee5 t\u00f9ng ti\u1ebfp x\u00fac tr\u1ef1c ti\u1ebfp) v\u00e0 316L cho h\u1ea1ng m\u1ee5c ph\u1ee5 tr\u1ee3; ho\u1eb7c 316L + l\u00f3t phi kim cho m\u00f4i tr\u01b0\u1eddng \u0111\u1eb7c bi\u1ec7t.<\/p>\n<h2 id=\"toc-7-quy-trinh-6-buoc-chon-nhanh-316l-hay-904l\">Quy tr\u00ecnh 6 b\u01b0\u1edbc ch\u1ecdn nhanh 316L hay 904L<\/h2>\n<p>1) X\u00e1c \u0111\u1ecbnh m\u00f4i ch\u1ea5t, n\u1ed3ng \u0111\u1ed9, nhi\u1ec7t \u0111\u1ed9 l\u00e0m vi\u1ec7c, t\u1ea1p ch\u1ea5t Cl-, Fe3+, SO2\/NOx.<br \/>\n2) Tra d\u1eef li\u1ec7u t\u01b0\u01a1ng th\u00edch (Outokumpu, Nickel Institute) \u0111\u1ec3 s\u00e0ng l\u1ecdc m\u00e1c.<br \/>\n3) Ki\u1ec3m tra r\u1ee7i ro SCC v\u1edbi Cl- v\u00e0 nhi\u1ec7t \u0111\u1ed9; n\u1ebfu T>60\u00b0C v\u00e0 c\u00f3 Cl-, \u01b0u ti\u00ean 904L.<br \/>\n4) \u0110\u00e1nh gi\u00e1 \u0111i\u1ec1u ki\u1ec7n th\u1ee7y l\u1ef1c (d\u00f2ng ch\u1ea3y t\u0129nh\/\u0111\u1ed9ng), kh\u1ea3 n\u0103ng k\u1ebd h\u1edf, v\u1ec7 sinh.<br \/>\n5) So s\u00e1nh chi ph\u00ed: 316L + bi\u1ec7n ph\u00e1p thi\u1ebft k\u1ebf\/ho\u00e0n thi\u1ec7n vs 904L nguy\u00ean kh\u1ed1i.<br \/>\n6) Ch\u1ed1t ti\u00eau chu\u1ea9n thi\u1ebft k\u1ebf, h\u00e0n, th\u1ee5 \u0111\u1ed9ng h\u00f3a v\u00e0 k\u1ebf ho\u1ea1ch QC\/inspections.<\/p>\n<h2 id=\"toc-8-vi-du-thuc-te-tai-viet-nam\">V\u00ed d\u1ee5 th\u1ef1c t\u1ebf t\u1ea1i Vi\u1ec7t Nam<\/h2>\n<p>&#8211; B\u1ed3n H2SO4 98% l\u01b0u kho, 30\u00b0C, Cl- <10 ppm: ch\u1ecdn 904L; h\u00e0n ER385; b\u1ec1 m\u1eb7t Ra \u22641.5 \u03bcm; hydrotest b\u1eb1ng n\u01b0\u1edbc DI.  \n- B\u1ed3n H3PO4 85% t\u1ea1i 60\u00b0C, Cl- 50 ppm: 904L ho\u1eb7c 316L l\u00f3t PTFE. V\u1edbi t\u1ea3i nhi\u1ec7t cao, 904L an to\u00e0n h\u01a1n v\u1ec1 tu\u1ed5i th\u1ecd.  \n- B\u1ed3n NaOH 32% \u1edf 50\u00b0C: 316L \u0111\u1ee7; ch\u00fa \u00fd tr\u00e1nh nhi\u1ec5m Cl- t\u1eeb n\u01b0\u1edbc r\u1eeda\/gi\u1eef v\u1ec7 sinh.  \n- B\u1ed3n HCl 30% \u1edf m\u00f4i tr\u01b0\u1eddng: kh\u00f4ng d\u00f9ng 316L\/904L; d\u00f9ng th\u00e9p carbon l\u00f3t cao su ho\u1eb7c FRP.  \n- B\u1ed3n n\u01b0\u1edbc bi\u1ec3n tu\u1ea7n ho\u00e0n: 904L d\u00f9ng \u0111\u01b0\u1ee3c n\u1ebfu d\u00f2ng ch\u1ea3y li\u00ean t\u1ee5c v\u00e0 ki\u1ec3m so\u00e1t fouling; tuy nhi\u00ean Duplex 2205 \u0111\u00e1ng c\u00e2n nh\u1eafc h\u01a1n v\u1ec1 hi\u1ec7u n\u0103ng \u2013 chi ph\u00ed.\n\n\n\n<h2 id=\"toc-9-nguon-tham-khao-ky-thuat\">Ngu\u1ed3n tham kh\u1ea3o k\u1ef9 thu\u1eadt<\/h2>\n<p>&#8211; Outokumpu Corrosion Handbook; Outokumpu datasheets 1.4404 (316L) v\u00e0 1.4539 (904L).<br \/>\n&#8211; Nickel Institute: Stainless Steels in Various Chemical Environments; Fabrication of Stainless Steels.<br \/>\n&#8211; ASTM A240, A312, A403, A182; ASTM A380\/A967; ASTM G48.<br \/>\n&#8211; ASME BPVC Section VIII Div.1; ASME IX; API 650\/620.<\/p>\n<h2 id=\"toc-10-ket-luan\">K\u1ebft lu\u1eadn<\/h2>\n<p>&#8211; 316L l\u00e0 l\u1ef1a ch\u1ecdn kinh t\u1ebf v\u00e0 \u0111\u1ee7 d\u00f9ng cho ki\u1ec1m, axit h\u1eefu c\u01a1, m\u1ed9t s\u1ed1 d\u1ecbch mu\u1ed1i lo\u00e3ng \u1edf nhi\u1ec7t \u0111\u1ed9 th\u1ea5p v\u00e0 m\u00f4i tr\u01b0\u1eddng s\u1ea1ch.<br \/>\n&#8211; 904L v\u01b0\u1ee3t tr\u1ed9i khi c\u00f3 H2SO4, H3PO4 n\u1ed3ng \u0111\u1ed9 cao, Cl- v\u1ebft, ho\u1eb7c nhi\u1ec7t \u0111\u1ed9 t\u0103ng \u2013 n\u01a1i 316L d\u1ec5 r\u1ed7\/SCC.<br \/>\n&#8211; HCl, NaOCl v\u00e0 t\u00e1c nh\u00e2n oxy h\u00f3a ch\u1ee9a clo: kh\u00f4ng ph\u00f9 h\u1ee3p c\u1ea3 316L\/904L \u2192 chuy\u1ec3n sang v\u1eadt li\u1ec7u\/gi\u1ea3i ph\u00e1p kh\u00e1c.<br \/>\n&#8211; Tu\u1ed5i th\u1ecd b\u1ed3n kh\u00f4ng ch\u1ec9 do m\u00e1c th\u00e9p m\u00e0 c\u00f2n \u1edf thi\u1ebft k\u1ebf ch\u1ed1ng k\u1ebd h\u1edf, quy tr\u00ecnh h\u00e0n \u2013 t\u1ea9y g\u1ec9 \u2013 th\u1ee5 \u0111\u1ed9ng h\u00f3a, ki\u1ec3m so\u00e1t Cl- trong th\u1eed k\u00edn v\u00e0 v\u1eadn h\u00e0nh.<br \/>\nL\u00e0m \u0111\u00fang ngay t\u1eeb \u0111\u1ea7u gi\u00fap tr\u00e1nh d\u1eebng m\u00e1y t\u1ed1n k\u00e9m, k\u00e9o d\u00e0i tu\u1ed5i th\u1ecd b\u1ed3n v\u00e0 an to\u00e0n h\u1ec7 th\u1ed1ng.<\/p>\n<p>C\u1ea7n t\u01b0 v\u1ea5n ch\u1ecdn v\u1eadt li\u1ec7u ho\u1eb7c b\u00e1o gi\u00e1 nhanh theo b\u1ea3n v\u1ebd, h\u00e3y li\u00ean h\u1ec7 Inox C\u01b0\u1eddng Th\u1ecbnh. Hotline: 0343.417.281. Email: inoxcongnghiep.cuongthinh@gmail.com<\/p>\n","protected":false},"excerpt":{"rendered":"<p>So s\u00e1nh 316L vs 904L theo m\u00f4i ch\u1ea5t, n\u1ed3ng \u0111\u1ed9, nhi\u1ec7t \u0111\u1ed9; h\u01b0\u1edbng d\u1eabn thi\u1ebft k\u1ebf, h\u00e0n, ho\u00e0n thi\u1ec7n v\u00e0 ti\u00eau chu\u1ea9n \u00e1p d\u1ee5ng cho b\u1ed3n ch\u1ee9a h\u00f3a ch\u1ea5t \u0103n m\u00f2n.<\/p>\n","protected":false},"author":7,"featured_media":1034,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[23],"tags":[],"class_list":["post-1322","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-tin-tuc"],"acf":[],"_links":{"self":[{"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/posts\/1322","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/comments?post=1322"}],"version-history":[{"count":0,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/posts\/1322\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/media\/1034"}],"wp:attachment":[{"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/media?parent=1322"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/categories?post=1322"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/tags?post=1322"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}