{"id":1509,"date":"2026-01-04T00:34:43","date_gmt":"2026-01-03T17:34:43","guid":{"rendered":"https:\/\/inoxcuongthinh.com\/vi-sao-inox-304-van-ri-set-nguyen-nhan-va-cach-xu-ly-triet-de\/"},"modified":"2026-01-04T00:34:43","modified_gmt":"2026-01-03T17:34:43","slug":"vi-sao-inox-304-van-ri-set-nguyen-nhan-va-cach-xu-ly-triet-de","status":"publish","type":"post","link":"https:\/\/inoxcuongthinh.com\/vi-sao-inox-304-van-ri-set-nguyen-nhan-va-cach-xu-ly-triet-de\/","title":{"rendered":"V\u00ec sao Inox 304 v\u1eabn r\u1ec9 s\u00e9t? Nguy\u00ean nh\u00e2n v\u00e0 c\u00e1ch x\u1eed l\u00fd tri\u1ec7t \u0111\u1ec3"},"content":{"rendered":"<div class=\"custom-toc\">\n<h3>N\u1ed9i dung ch\u00ednh<\/h3>\n<ul>\n<li><a href=\"#toc-0-tom-tat-nhanh-khi-nao-inox-304-co-the-ri\">T\u00f3m t\u1eaft nhanh: Khi n\u00e0o Inox 304 c\u00f3 th\u1ec3 r\u1ec9?<\/a><\/li>\n<li><a href=\"#toc-1-co-che-chong-an-mon-cua-inox-304-va-gioi-han\">C\u01a1 ch\u1ebf ch\u1ed1ng \u0103n m\u00f2n c\u1ee7a Inox 304 v\u00e0 gi\u1edbi h\u1ea1n<\/a><\/li>\n<li><a href=\"#toc-2-nguyen-nhan-pho-bien-khien-304-ri-set-tai-cong-tri\">Nguy\u00ean nh\u00e2n ph\u1ed5 bi\u1ebfn khi\u1ebfn 304 r\u1ec9 s\u00e9t t\u1ea1i c\u00f4ng tr\u00ecnh<\/a><\/li>\n<li><a href=\"#toc-3-phan-biet-ri-ban-va-an-mon-that\">Ph\u00e2n bi\u1ec7t \u201cr\u1ec9 b\u1ea9n\u201d v\u00e0 \u0103n m\u00f2n th\u1eadt<\/a><\/li>\n<li><a href=\"#toc-4-quy-trinh-xu-ly-triet-de-ri-set-tren-inox-304\">Quy tr\u00ecnh x\u1eed l\u00fd tri\u1ec7t \u0111\u1ec3 r\u1ec9 s\u00e9t tr\u00ean Inox 304<\/a><\/li>\n<li><a href=\"#toc-5-bao-duong-phong-ngua-theo-moi-truong\">B\u1ea3o d\u01b0\u1ee1ng ph\u00f2ng ng\u1eeba theo m\u00f4i tr\u01b0\u1eddng<\/a><\/li>\n<li><a href=\"#toc-6-kiem-tra-va-xac-minh-vat-lieu\">Ki\u1ec3m tra v\u00e0 x\u00e1c minh v\u1eadt li\u1ec7u<\/a><\/li>\n<li><a href=\"#toc-7-hoi-nhanh-dap-gon\">H\u1ecfi nhanh \u2013 \u0111\u00e1p g\u1ecdn<\/a><\/li>\n<li><a href=\"#toc-8-nguon-tham-khao\">Ngu\u1ed3n tham kh\u1ea3o<\/a><\/li>\n<li><a href=\"#toc-9-ket-luan\">K\u1ebft lu\u1eadn<\/a><\/li>\n<\/ul>\n<\/div>\n<p>Inox 304 \u0111\u01b0\u1ee3c \u01b0a chu\u1ed9ng v\u00ec ch\u1ed1ng \u0103n m\u00f2n t\u1ed1t v\u00e0 d\u1ec5 gia c\u00f4ng. Tuy nhi\u00ean, kh\u00f4ng \u00edt c\u00f4ng tr\u00ecnh t\u1ea1i H\u00e0 N\u1ed9i v\u00e0 ven bi\u1ec3n mi\u1ec1n B\u1eafc v\u1eabn th\u1ea5y 304 \u201c\u1ed1 v\u00e0ng\u201d, r\u1ed7 ho\u1eb7c r\u1ec9 loang. B\u00e0i vi\u1ebft n\u00e0y gi\u1ea3i th\u00edch v\u00ec sao inox 304 v\u1eabn b\u1ecb r\u1ec9 s\u00e9t, c\u00e1ch ch\u1ea9n \u0111o\u00e1n \u0111\u00fang nguy\u00ean nh\u00e2n v\u00e0 quy tr\u00ecnh x\u1eed l\u00fd tri\u1ec7t \u0111\u1ec3. \u0110\u00e2y l\u00e0 ph\u1ea7n tr\u1ecdng y\u1ebfu trong b\u1ea3o d\u01b0\u1ee1ng \u2013 v\u1ec7 sinh \u2013 ph\u1ee5c h\u1ed3i c\u00e1c s\u1ea3n ph\u1ea9m inox \u0111\u1ec3 \u0111\u1ea1t tu\u1ed5i th\u1ecd thi\u1ebft k\u1ebf.<\/p>\n<h2 id=\"toc-0-tom-tat-nhanh-khi-nao-inox-304-co-the-ri\">T\u00f3m t\u1eaft nhanh: Khi n\u00e0o Inox 304 c\u00f3 th\u1ec3 r\u1ec9?<\/h2>\n<p>&#8211; M\u00f4i tr\u01b0\u1eddng c\u00f3 clo\/mu\u1ed1i (ven bi\u1ec3n, h\u1ed3 b\u01a1i, dung d\u1ecbch t\u1ea9y Javen\/NaClO, HCl): d\u1ec5 r\u1ed7 (pitting), \u1ed1 tr\u00e0 (tea staining).<br \/>\n&#8211; V\u00f9ng h\u00e0n b\u1ecb ch\u00e1y m\u00e0u, kh\u00f4ng pickling\/passivation sau h\u00e0n: m\u00e0ng th\u1ee5 \u0111\u1ed9ng suy y\u1ebfu, d\u1ec5 r\u1ec9.<br \/>\n&#8211; Nhi\u1ec5m s\u1eaft t\u1ef1 do do gia c\u00f4ng b\u1eb1ng d\u1ee5ng c\u1ee5 th\u00e9p carbon, b\u1ee5i m\u00e0i, b\u1eafn to\u00e9 kim lo\u1ea1i.<br \/>\n&#8211; N\u01b0\u1edbc \u0111\u1ecdng, khe k\u1ebd, l\u1ed7 b\u1ea9n t\u00edch t\u1ee5 mu\u1ed1i\/b\u1ee5i l\u00e0m thi\u1ebfu oxy: \u0103n m\u00f2n k\u1ebd.<br \/>\n&#8211; V\u1eadt li\u1ec7u k\u00e9m ti\u00eau chu\u1ea9n (Cr\/Ni th\u1ea5p h\u01a1n ASTM), sai m\u00e1c, ho\u1eb7c thi\u1ebft k\u1ebf\/thi c\u00f4ng kh\u00f4ng \u0111\u00fang.<br \/>\n&#8211; \u0102n m\u00f2n \u0111i\u1ec7n h\u00f3a khi ti\u1ebfp x\u00fac kim lo\u1ea1i kh\u00e1c m\u00e0 kh\u00f4ng c\u00e1ch \u0111i\u1ec7n.<\/p>\n<h2 id=\"toc-1-co-che-chong-an-mon-cua-inox-304-va-gioi-han\">C\u01a1 ch\u1ebf ch\u1ed1ng \u0103n m\u00f2n c\u1ee7a Inox 304 v\u00e0 gi\u1edbi h\u1ea1n<\/h2>\n<p>&#8211; Inox 304 h\u00ecnh th\u00e0nh m\u00e0ng th\u1ee5 \u0111\u1ed9ng Cr2O3 c\u1ef1c m\u1ecfng t\u1ef1 t\u00e1i t\u1ea1o trong m\u00f4i tr\u01b0\u1eddng c\u00f3 oxy. Th\u00e0nh ph\u1ea7n ti\u00eau chu\u1ea9n: Cr 18\u201320%, Ni 8\u201310.5%, C \u2264 0.08% (304L: C \u2264 0.03%) theo ASTM A240.<br \/>\n&#8211; Trong m\u00f4i tr\u01b0\u1eddng clorua, m\u00e0ng th\u1ee5 \u0111\u1ed9ng c\u00f3 th\u1ec3 b\u1ecb xuy\u00ean th\u1ee7ng t\u1ea1i \u0111i\u1ec3m khuy\u1ebft t\u1eadt \u2192 g\u00e2y r\u1ed7 (pitting) v\u00e0 \u0103n m\u00f2n k\u1ebd (crevice). 304 c\u00f3 ch\u1ec9 s\u1ed1 PREN ~18\u201319, th\u1ea5p h\u01a1n 316 (PREN ~24) n\u00ean k\u00e9m b\u1ec1n clo h\u01a1n.<br \/>\n[Ngu\u1ed3n: BSSA; Nickel Institute]<\/p>\n<h2 id=\"toc-2-nguyen-nhan-pho-bien-khien-304-ri-set-tai-cong-tri\">Nguy\u00ean nh\u00e2n ph\u1ed5 bi\u1ebfn khi\u1ebfn 304 r\u1ec9 s\u00e9t t\u1ea1i c\u00f4ng tr\u00ecnh<\/h2>\n<h3>1) Clo\/mu\u1ed1i v\u00e0 \u201ctea staining\u201d<\/h3>\n<p>&#8211; Kh\u00f4ng kh\u00ed ven bi\u1ec3n, b\u1eafn n\u01b0\u1edbc m\u1eb7n, n\u01b0\u1edbc r\u1eeda c\u00f3 ion Cl- ho\u1eb7c h\u00f3a ch\u1ea5t t\u1ea9y clo (NaClO, Ca(ClO)2) g\u00e2y \u1ed1 n\u00e2u, \u1ed1 tr\u00e0 r\u1ed3i ti\u1ebfn tri\u1ec3n th\u00e0nh r\u1ed7.<br \/>\n&#8211; R\u1ee7i ro t\u0103ng m\u1ea1nh khi b\u1ec1 m\u1eb7t th\u00f4 (No.1, 2B x\u01b0\u1edbc, hairline ch\u01b0a b\u1ecbt k\u00edn), nhi\u1ec7t \u0111\u1ed9 cao, b\u1ea3o d\u01b0\u1ee1ng k\u00e9m, ho\u1eb7c thi\u1ebft k\u1ebf t\u1ea1o \u0111\u1ecdng n\u01b0\u1edbc.<br \/>\n[Ngu\u1ed3n: ASSDA \u2013 Tea Staining; Outokumpu]<\/p>\n<h3>2) Nhi\u1ec5m s\u1eaft t\u1ef1 do (free iron\/rouge)<\/h3>\n<p>&#8211; D\u00f9ng b\u00e0n ch\u1ea3i, \u0111\u0129a m\u00e0i th\u00e9p carbon, c\u00f9ng ch\u1ed7 gia c\u00f4ng cho th\u00e9p th\u01b0\u1eddng v\u00e0 inox; h\u1ea1t m\u00e0i mang s\u1eaft b\u00e1m l\u00ean b\u1ec1 m\u1eb7t inox. S\u1eaft n\u00e0y r\u1ec9 tr\u01b0\u1edbc, lan ra b\u1ec1 m\u1eb7t.<br \/>\n&#8211; Th\u01b0\u1eddng th\u1ea5y d\u1ea1ng v\u1ec7t r\u1ec9 m\u1ea3nh, m\u1ecbn; c\u1ea1o nh\u1eb9 c\u00f3 th\u1ec3 bong.<br \/>\n[Ngu\u1ed3n: ASTM A380]<\/p>\n<h3>3) H\u00e0n kh\u00f4ng \u0111\u00fang quy tr\u00ecnh<\/h3>\n<p>&#8211; M\u00e0u ch\u00e1y (heat tint) v\u00e0 x\u1ec9 \u00f4x\u00edt sau h\u00e0n l\u00e0m gi\u1ea3m Cr c\u1ee5c b\u1ed9; n\u1ebfu kh\u00f4ng pickling v\u00e0 passivation, v\u00f9ng HAZ r\u1ec9 r\u1ea5t nhanh.<br \/>\n&#8211; Nh\u1ea1y c\u1ea3m k\u1ebft tinh bi\u00ean (sensitization) 450\u2013850\u00b0C g\u00e2y k\u1ebft t\u1ee7a Cr23C6; 304L gi\u1ea3m r\u1ee7i ro n\u00e0y.<br \/>\n[Ngu\u1ed3n: ASTM A380; Nickel Institute]<\/p>\n<h3>4) N\u01b0\u1edbc \u0111\u1ecdng, khe k\u1ebd, b\u00e1m b\u1ea9n<\/h3>\n<p>&#8211; \u1ede khe, ch\u00e2n \u0111\u1ebf, ren, m\u1eb7t d\u01b0\u1edbi t\u1ea5m, thi\u1ebfu oxy l\u00e0m m\u00e0ng th\u1ee5 \u0111\u1ed9ng kh\u00f4ng t\u00e1i t\u1ea1o, ion Cl- t\u1eadp trung \u2192 \u0103n m\u00f2n k\u1ebd.<br \/>\n&#8211; B\u1ee5i c\u00f4ng nghi\u1ec7p, SOx\/NOx, mu\u1ed1i \u0111\u01b0\u1eddng\u2026 gi\u1eef \u1ea9m v\u00e0 t\u0103ng d\u1eabn \u0111i\u1ec7n.<br \/>\n[Ngu\u1ed3n: BSSA]<\/p>\n<h3>5) H\u00f3a ch\u1ea5t t\u1ea9y r\u1eeda sai<\/h3>\n<p>&#8211; HCl, ch\u1ea5t t\u1ea9y g\u1ed1c clo (Javen), ch\u1ea5t t\u1ea9y r\u1ec9 m\u1ea1nh cho b\u00ea t\u00f4ng, axit halogen\u2026 t\u1ea5n c\u00f4ng inox 304, \u0111\u1eb7c bi\u1ec7t khi nhi\u1ec7t \u0111\u1ed9 cao.<br \/>\n&#8211; D\u01b0 l\u01b0\u1ee3ng mu\u1ed1i\/axit kh\u00f4ng r\u1eeda k\u1ef9 ti\u1ebfp t\u1ee5c \u0103n m\u00f2n.<br \/>\n[Ngu\u1ed3n: Nickel Institute]<\/p>\n<h3>6) V\u1eadt li\u1ec7u sai m\u00e1c ho\u1eb7c k\u00e9m ch\u1ea5t l\u01b0\u1ee3ng<\/h3>\n<p>&#8211; Cr\/Ni th\u1ea5p h\u01a1n chu\u1ea9n ho\u1eb7c tr\u1ed9n l\u1eabn; thi\u1ebfu ch\u1ee9ng ch\u1ec9 MTC\/PMI.<br \/>\n&#8211; B\u1ec1 m\u1eb7t c\u00e1n th\u00f4, x\u01b0\u1edbc s\u00e2u, kh\u00f4ng ph\u1ee7 b\u1ea3o v\u1ec7 trong v\u1eadn chuy\u1ec3n.<\/p>\n<h3>7) \u0102n m\u00f2n \u0111i\u1ec7n h\u00f3a<\/h3>\n<p>&#8211; 304 n\u1ed1i v\u1edbi th\u00e9p carbon\/nh\u00f4m\/\u0111\u1ed3ng trong m\u00f4i tr\u01b0\u1eddng \u1ea9m m\u00e0 kh\u00f4ng c\u00e1ch \u0111i\u1ec7n \u2192 304 th\u00e0nh c\u1ef1c d\u01b0\u01a1ng c\u1ee5c b\u1ed9 v\u00e0 r\u1ec9 t\u1ea1i m\u1ed1i n\u1ed1i.<\/p>\n<h2 id=\"toc-3-phan-biet-ri-ban-va-an-mon-that\">Ph\u00e2n bi\u1ec7t \u201cr\u1ec9 b\u1ea9n\u201d v\u00e0 \u0103n m\u00f2n th\u1eadt<\/h2>\n<p>&#8211; Quan s\u00e1t nhanh:<br \/>\n  &#8211; R\u1ec9 b\u1ea9n\/nhi\u1ec5m s\u1eaft: v\u1ec7t n\u00e2u m\u1ecfng, ph\u00e2n b\u1ed1 theo d\u00f2ng n\u01b0\u1edbc, c\u1ea1o\/\u0111\u00e1nh pad nylon c\u00f3 th\u1ec3 s\u1ea1ch, kh\u00f4ng th\u1ea5y h\u1ed1 r\u1ed7.<br \/>\n  &#8211; \u0102n m\u00f2n r\u1ed7\/k\u1ebd: c\u00f3 l\u1ed7 kim, b\u1ec1 m\u1eb7t s\u1ea7n, m\u00e9p h\u1ed1 t\u1ed1i; lau kh\u00f4ng h\u1ebft.<br \/>\n&#8211; Th\u1eed nghi\u1ec7m \u0111\u01a1n gi\u1ea3n:<br \/>\n  &#8211; L\u00e0m s\u1ea1ch d\u1ea7u m\u1ee1, nh\u1ecf n\u01b0\u1edbc s\u1ea1ch: n\u1ebfu n\u01b0\u1edbc lan \u0111\u1ec1u th\u00e0nh m\u00e0ng (water-break free) sau passivation, b\u1ec1 m\u1eb7t th\u01b0\u1eddng \u1ed5n.<br \/>\n  &#8211; Th\u1eed Ferroxyl (theo ASTM A380) ph\u00e1t hi\u1ec7n s\u1eaft t\u1ef1 do.<br \/>\n&#8211; Ki\u1ec3m tra m\u00e1c v\u1eadt li\u1ec7u:<br \/>\n  &#8211; D\u00f9ng PMI\/XRF, \u0111\u1ed1i chi\u1ebfu ch\u1ee9ng ch\u1ec9 EN 10204 3.1. 304 kh\u00f4ng ch\u1ee9a Mo; n\u1ebfu c\u00f3 ~2% Mo l\u00e0 316.<br \/>\n[Ngu\u1ed3n: ASTM A380; BSSA]<\/p>\n<h2 id=\"toc-4-quy-trinh-xu-ly-triet-de-ri-set-tren-inox-304\">Quy tr\u00ecnh x\u1eed l\u00fd tri\u1ec7t \u0111\u1ec3 r\u1ec9 s\u00e9t tr\u00ean Inox 304<\/h2>\n<p>L\u01b0u \u00fd an to\u00e0n: D\u00f9ng g\u0103ng, k\u00ednh, m\u1eb7t n\u1ea1; th\u00f4ng gi\u00f3 t\u1ed1t. H\u00f3a ch\u1ea5t pickling c\u00f3 HF r\u1ea5t nguy hi\u1ec3m \u2013 ch\u1ec9 k\u1ef9 thu\u1eadt vi\u00ean \u0111\u01b0\u1ee3c hu\u1ea5n luy\u1ec7n m\u1edbi th\u1ef1c hi\u1ec7n.<\/p>\n<p>&#8211; B\u01b0\u1edbc 1: X\u00e1c \u0111\u1ecbnh nguy\u00ean nh\u00e2n<br \/>\n  &#8211; Ghi nh\u1eadn v\u1ecb tr\u00ed, m\u00f4i tr\u01b0\u1eddng (ven bi\u1ec3n, h\u00f3a ch\u1ea5t, h\u1ed3 b\u01a1i), c\u00f3 m\u1ed1i h\u00e0n\/khe k\u1ebd hay kh\u00f4ng, l\u1ecbch b\u1ea3o d\u01b0\u1ee1ng.<br \/>\n&#8211; B\u01b0\u1edbc 2: V\u1ec7 sinh s\u01a1 b\u1ed9 v\u00e0 t\u1ea9y d\u1ea7u<br \/>\n  &#8211; D\u00f9ng ch\u1ea5t t\u1ea9y trung t\u00ednh\/ki\u1ec1m nh\u1eb9 pH 7\u201310; kh\u00f4ng d\u00f9ng HCl\/Javen. Ch\u00e0 b\u1eb1ng pad nylon ho\u1eb7c v\u1ea3i m\u1ec1m theo th\u1edb x\u01b0\u1edbc. R\u1eeda n\u01b0\u1edbc s\u1ea1ch, lau kh\u00f4.<br \/>\n&#8211; B\u01b0\u1edbc 3: Lo\u1ea1i b\u1ecf r\u1ec9\/nhi\u1ec5m s\u1eaft c\u01a1 h\u1ecdc<br \/>\n  &#8211; D\u00f9ng pad Scotch-Brite kh\u00f4ng ch\u1ee9a s\u1eaft, h\u1ea1t m\u00e0i d\u00e0nh ri\u00eang cho inox. Tuy\u1ec7t \u0111\u1ed1i kh\u00f4ng d\u00f9ng b\u00e0n ch\u1ea3i th\u00e9p carbon hay len th\u00e9p.<br \/>\n&#8211; B\u01b0\u1edbc 4: T\u1ea9y g\u1ec9 \u2013 t\u1ea9y x\u1ec9 h\u00e0n (pickling) khi c\u00f3 ch\u00e1y m\u00e0u\/x\u1ec9<br \/>\n  &#8211; D\u00f9ng gel\/t\u1eafm pickling g\u1ed1c HNO3 + HF \u0111\u1ec3 lo\u1ea1i l\u1edbp \u00f4x\u00edt d\u00e0y sau h\u00e0n, theo h\u01b0\u1edbng d\u1eabn nh\u00e0 s\u1ea3n xu\u1ea5t; x\u1eed l\u00fd ch\u1ea5t th\u1ea3i \u0111\u00fang quy \u0111\u1ecbnh. N\u1ebfu kh\u00f4ng b\u1eaft bu\u1ed9c, \u01b0u ti\u00ean ph\u01b0\u01a1ng \u00e1n kh\u00f4ng HF.<br \/>\n  &#8211; Thay th\u1ebf an to\u00e0n h\u01a1n: t\u1ea9y b\u1eb1ng axit photphoric cho \u1ed1 nh\u1eb9, sau \u0111\u00f3 passivation.<br \/>\n  [Ngu\u1ed3n: ASTM A380]<br \/>\n&#8211; B\u01b0\u1edbc 5: Th\u1ee5 \u0111\u1ed9ng h\u00f3a (passivation) theo chu\u1ea9n<br \/>\n  &#8211; ASTM A967:<br \/>\n    &#8211; Dung d\u1ecbch nitric 20\u201350% \u1edf 20\u201360\u00b0C trong 20\u201330 ph\u00fat, ho\u1eb7c<br \/>\n    &#8211; Dung d\u1ecbch citric 4\u201310% \u1edf 20\u201360\u00b0C trong 10\u201330 ph\u00fat.<br \/>\n  &#8211; M\u1ee5c ti\u00eau: h\u00f2a tan s\u1eaft t\u1ef1 do v\u00e0 l\u00e0m gi\u00e0u Cr b\u1ec1 m\u1eb7t, kh\u00f4i ph\u1ee5c m\u00e0ng th\u1ee5 \u0111\u1ed9ng.<br \/>\n  [Ngu\u1ed3n: ASTM A967]<br \/>\n&#8211; B\u01b0\u1edbc 6: R\u1eeda \u2013 trung h\u00f2a \u2013 s\u1ea5y kh\u00f4<br \/>\n  &#8211; R\u1eeda n\u01b0\u1edbc s\u1ea1ch \u00e1p l\u1ef1c v\u1eeba; n\u1ebfu d\u00f9ng axit, trung h\u00f2a theo khuy\u1ebfn ngh\u1ecb; s\u1ea5y kh\u00f4 \u0111\u1ec3 tr\u00e1nh v\u1ec7t mu\u1ed1i.<br \/>\n&#8211; B\u01b0\u1edbc 7: Ki\u1ec3m tra l\u1ea1i<br \/>\n  &#8211; Quan s\u00e1t r\u1ed7, l\u00e0m th\u1eed water-break. V\u1edbi y\u00eau c\u1ea7u cao (th\u1ef1c ph\u1ea9m\/\u0111i\u1ec7n t\u1eed), c\u00e2n nh\u1eafc \u0111i\u1ec7n h\u00f3a \u0111\u00e1nh b\u00f3ng (electropolishing) \u0111\u1ec3 t\u0103ng \u0111\u1ed9 th\u1ee5 \u0111\u1ed9ng v\u00e0 gi\u1ea3m nh\u00e1m.<br \/>\n&#8211; B\u01b0\u1edbc 8: B\u1ea3o v\u1ec7 b\u1ed5 sung (khi m\u00f4i tr\u01b0\u1eddng kh\u1eafc nghi\u1ec7t)<br \/>\n  &#8211; D\u00f9ng sealant\/s\u01a1n trong su\u1ed1t chuy\u00ean d\u1ee5ng cho inox \u1edf ngo\u1ea1i th\u1ea5t; ho\u1eb7c xem x\u00e9t n\u00e2ng c\u1ea5p h\u1ee3p kim (316\/2205) t\u1ea1i v\u00f9ng \u0111\u1eb7c bi\u1ec7t kh\u1eafc nghi\u1ec7t.<\/p>\n<h2 id=\"toc-5-bao-duong-phong-ngua-theo-moi-truong\">B\u1ea3o d\u01b0\u1ee1ng ph\u00f2ng ng\u1eeba theo m\u00f4i tr\u01b0\u1eddng<\/h2>\n<p>&#8211; Trong nh\u00e0 kh\u00f4 ho\u1eb7c \u1ea9m nh\u1eb9 (x\u01b0\u1edfng, v\u0103n ph\u00f2ng):<br \/>\n  &#8211; Chu k\u1ef3 v\u1ec7 sinh: 3\u20136 th\u00e1ng.<br \/>\n  &#8211; D\u00f9ng ch\u1ea5t t\u1ea9y trung t\u00ednh\/ki\u1ec1m nh\u1eb9; lau kh\u00f4 sau r\u1eeda.<br \/>\n&#8211; Ngo\u00e0i tr\u1eddi \u0111\u00f4 th\u1ecb\/c\u00f4ng nghi\u1ec7p (b\u1ee5i, SOx\/NOx):<br \/>\n  &#8211; Chu k\u1ef3: 1\u20133 th\u00e1ng. R\u1eeda n\u01b0\u1edbc s\u1ea1ch \u0111\u1ec3 lo\u1ea1i mu\u1ed1i\/b\u1ee5i, sau \u0111\u00f3 t\u1ea9y r\u1eeda nh\u1eb9.<br \/>\n&#8211; Ven bi\u1ec3n (<5 km b\u1edd bi\u1ec3n) ho\u1eb7c g\u1ea7n h\u1ed3 b\u01a1i:\n  - Chu k\u1ef3: h\u00e0ng tu\u1ea7n \u0111\u1ebfn h\u00e0ng th\u00e1ng t\u00f9y ph\u01a1i nhi\u1ec5m. R\u1eeda n\u01b0\u1edbc ng\u1ecdt \u00e1p l\u1ef1c th\u1ea5p \u0111\u1ec3 cu\u1ed1n mu\u1ed1i; v\u1ec7 sinh b\u1eb1ng dung d\u1ecbch trung t\u00ednh; \u0111\u1ecbnh k\u1ef3 passivation b\u1eb1ng dung d\u1ecbch citric.\n  - C\u00e2n nh\u1eafc b\u1ec1 m\u1eb7t m\u1ecbn h\u01a1n (No.4 tinh, 240\u2013320 grit) ho\u1eb7c electropolish; h\u1ea1n ch\u1ebf khe k\u1ebd, thi\u1ebft k\u1ebf tho\u00e1t n\u01b0\u1edbc t\u1ed1t. V\u1edbi tay v\u1ecbn, m\u1eb7t d\u1ef1ng ngo\u00e0i tr\u1eddi: \u01b0u ti\u00ean 316\/316L.\n- Sau h\u00e0n\/l\u1eafp \u0111\u1eb7t:\n  - Pickling + passivation b\u1eaft bu\u1ed9c \u1edf v\u00f9ng ch\u00e1y m\u00e0u; d\u00f9ng ch\u1ed5i inox ri\u00eang; back purging cho m\u1ed1i h\u00e0n \u1ed1ng\/quanh kh\u00ed.\n- H\u00f3a ch\u1ea5t n\u00ean\/kh\u00f4ng n\u00ean d\u00f9ng:\n  - N\u00ean: x\u00e0 ph\u00f2ng trung t\u00ednh, ch\u1ea5t t\u1ea9y d\u1ea7u ki\u1ec1m nh\u1eb9, c\u1ed3n isopropyl cho d\u1ea5u v\u00e2n tay, dung d\u1ecbch citric\/passivation chuy\u00ean d\u1ee5ng.\n  - Tr\u00e1nh: HCl, ch\u1ea5t t\u1ea9y g\u1ed1c clo (NaClO\/Javen), mu\u1ed1i \u0103n, thu\u1ed1c t\u1ea9y r\u1ec9 cho b\u00ea t\u00f4ng, len th\u00e9p.\n[Ngu\u1ed3n: ASSDA; Nickel Institute; BSSA]\n\n\n\n<h2 id=\"toc-6-kiem-tra-va-xac-minh-vat-lieu\">Ki\u1ec3m tra v\u00e0 x\u00e1c minh v\u1eadt li\u1ec7u<\/h2>\n<p>&#8211; Ch\u1ee9ng ch\u1ec9 MTC (EN 10204 3.1) v\u1edbi heat number r\u00f5 r\u00e0ng.<br \/>\n&#8211; Ki\u1ec3m tra PMI\/XRF t\u1ea1i hi\u1ec7n tr\u01b0\u1eddng \u0111\u1ec3 x\u00e1c nh\u1eadn 304\/304L; 316 c\u00f3 Mo ~2.0\u20132.5%.<br \/>\n&#8211; V\u1edbi y\u00eau c\u1ea7u clo cao (h\u1ed3 b\u01a1i, ven bi\u1ec3n tr\u1ef1c di\u1ec7n s\u00f3ng), c\u00e2n nh\u1eafc chuy\u1ec3n 316\/316L ho\u1eb7c duplex 2205 \u0111\u1ec3 t\u0103ng PREN v\u00e0 ch\u1ed1ng r\u1ed7.<br \/>\n[Ngu\u1ed3n: Nickel Institute; IMOA]<\/p>\n<h2 id=\"toc-7-hoi-nhanh-dap-gon\">H\u1ecfi nhanh \u2013 \u0111\u00e1p g\u1ecdn<\/h2>\n<p>&#8211; Inox 304 c\u00f3 r\u1ec9 v\u0129nh vi\u1ec5n kh\u00f4ng?<br \/>\n  &#8211; Kh\u00f4ng. \u0110a s\u1ed1 l\u00e0 \u1ed1 b\u1ea9n\/nhi\u1ec5m s\u1eaft x\u1eed l\u00fd \u0111\u01b0\u1ee3c b\u1eb1ng l\u00e0m s\u1ea1ch, pickling v\u00e0 passivation \u0111\u00fang quy tr\u00ecnh.<br \/>\n&#8211; D\u00f9ng Javen v\u1ec7 sinh inox \u0111\u01b0\u1ee3c kh\u00f4ng?<br \/>\n  &#8211; Kh\u00f4ng khuy\u1ebfn ngh\u1ecb. Clo g\u00e2y r\u1ed7 v\u00e0 \u1ed1 tr\u00e0; n\u1ebfu b\u1eaft bu\u1ed9c d\u00f9ng kh\u1eed tr\u00f9ng clo, ph\u1ea3i r\u1eeda x\u1ed1i n\u01b0\u1edbc s\u1ea1ch v\u00e0 lau kh\u00f4 ngay.<br \/>\n&#8211; T\u1ea1i sao v\u00f9ng h\u00e0n r\u1ec9 nhanh nh\u1ea5t?<br \/>\n  &#8211; Ch\u00e1y m\u00e0u l\u00e0m ngh\u00e8o Cr v\u00e0 t\u1ea1o \u00f4x\u00edt d\u00e0y; n\u1ebfu kh\u00f4ng pickling\/passivation, m\u00e0ng th\u1ee5 \u0111\u1ed9ng kh\u00f4ng kh\u00f4i ph\u1ee5c \u0111\u1ee7.<br \/>\n&#8211; 304 hay 316 cho ven bi\u1ec3n?<br \/>\n  &#8211; 316 (c\u00f3 Mo) ch\u1ed1ng r\u1ed7 t\u1ed1t h\u01a1n; 304 ch\u1ec9 ph\u00f9 h\u1ee3p khi b\u1ea3o d\u01b0\u1ee1ng r\u1ea5t t\u1ed1t v\u00e0 kh\u00f4ng tr\u1ef1c di\u1ec7n phun s\u01b0\u01a1ng m\u1eb7n.<\/p>\n<h2 id=\"toc-8-nguon-tham-khao\">Ngu\u1ed3n tham kh\u1ea3o<\/h2>\n<p>&#8211; ASTM A380\/A380M \u2013 Standard Practice for Cleaning, Descaling, and Passivation of Stainless Steel Parts.<br \/>\n&#8211; ASTM A967\/A967M \u2013 Chemical Passivation Treatments for Stainless Steel Parts.<br \/>\n&#8211; ASSDA Technical Bulletin: Preventing Tea Staining on Stainless Steel \u2013 https:\/\/www.assda.asn.au\/technical-info\/technical-faqs\/tea-staining<br \/>\n&#8211; Nickel Institute \u2013 Cleaning and maintenance of stainless steel; chloride effects \u2013 https:\/\/nickelinstitute.org<br \/>\n&#8211; BSSA (British Stainless Steel Association) \u2013 Cleaning stainless steel; fabrication guidance \u2013 https:\/\/bssa.org.uk<br \/>\n&#8211; Outokumpu Knowledge Center \u2013 Technical articles on stainless steel surfaces and corrosion \u2013 https:\/\/www.outokumpu.com\/en\/expertise\/knowledge-center<br \/>\n&#8211; IMOA \u2013 Tea staining and alloy selection near coasts \u2013 https:\/\/www.imoa.info<\/p>\n<h2 id=\"toc-9-ket-luan\">K\u1ebft lu\u1eadn<\/h2>\n<p>Inox 304 ch\u1ed1ng \u0103n m\u00f2n t\u1ed1t nh\u01b0ng kh\u00f4ng \u201cmi\u1ec5n d\u1ecbch\u201d v\u1edbi clo, nhi\u1ec7t \u1ea3nh h\u01b0\u1edfng h\u00e0n, nhi\u1ec5m s\u1eaft v\u00e0 \u0111i\u1ec1u ki\u1ec7n \u0111\u1ecdng n\u01b0\u1edbc. Ch\u00eca kh\u00f3a l\u00e0: ch\u1ecdn \u0111\u00fang v\u1eadt li\u1ec7u\/ho\u00e0n thi\u1ec7n b\u1ec1 m\u1eb7t, thi c\u00f4ng \u0111\u00fang (pickling + passivation sau h\u00e0n), v\u1ec7 sinh \u0111\u1ecbnh k\u1ef3 b\u1eb1ng h\u00f3a ch\u1ea5t ph\u00f9 h\u1ee3p v\u00e0 thi\u1ebft k\u1ebf gi\u1ea3m \u0111\u1ecdng n\u01b0\u1edbc \u2013 khe k\u1ebd. Khi \u0111\u00e3 xu\u1ea5t hi\u1ec7n r\u1ec9, x\u1eed l\u00fd tri\u1ec7t \u0111\u1ec3 g\u1ed3m l\u00e0m s\u1ea1ch, t\u1ea9y c\u01a1 h\u1ecdc, pickling (khi c\u1ea7n) v\u00e0 passivation theo ASTM A967. V\u1edbi m\u00f4i tr\u01b0\u1eddng ven bi\u1ec3n\/h\u1ed3 b\u01a1i, n\u00ean n\u00e2ng c\u1ea5p sang 316\/316L ho\u1eb7c b\u1ea3o v\u1ec7 b\u1ec1 m\u1eb7t t\u1ed1t h\u01a1n \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o tu\u1ed5i th\u1ecd.<\/p>\n<p>C\u1ea7n t\u01b0 v\u1ea5n ch\u1ecdn m\u00e1c th\u00e9p, quy tr\u00ecnh x\u1eed l\u00fd t\u1ea1i hi\u1ec7n tr\u01b0\u1eddng ho\u1eb7c b\u00e1o gi\u00e1 v\u1eadt t\u01b0 \u2013 d\u1ecbch v\u1ee5 pickling\/passivation? Li\u00ean h\u1ec7 Inox Cuong Thinh: Hotline 0343.417.281 \u00b7 Email inoxcongnghiep.cuongthinh@gmail.com \u0111\u1ec3 \u0111\u01b0\u1ee3c chuy\u00ean gia h\u1ed7 tr\u1ee3 v\u00e0 nh\u1eadn b\u00e1o gi\u00e1 t\u1ed1t nh\u1ea5t.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Inox 304 v\u1eabn c\u00f3 th\u1ec3 r\u1ec9 b\u1edfi clo, h\u00e0n, nhi\u1ec5m s\u1eaft, n\u01b0\u1edbc \u0111\u1ecdng. B\u00e0i vi\u1ebft n\u00eau nguy\u00ean nh\u00e2n, c\u00e1ch ph\u00e2n bi\u1ec7t v\u00e0 quy tr\u00ecnh pickling\u2013passivation, b\u1ea3o d\u01b0\u1ee1ng.<\/p>\n","protected":false},"author":7,"featured_media":1057,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[23],"tags":[],"class_list":["post-1509","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\/1509","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=1509"}],"version-history":[{"count":0,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/posts\/1509\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/media\/1057"}],"wp:attachment":[{"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/media?parent=1509"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/categories?post=1509"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/tags?post=1509"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}