{"id":2121,"date":"2026-06-09T12:33:39","date_gmt":"2026-06-09T05:33:39","guid":{"rendered":"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/"},"modified":"2026-06-09T12:33:39","modified_gmt":"2026-06-09T05:33:39","slug":"nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc","status":"publish","type":"post","link":"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/","title":{"rendered":"N\u1ee9t m\u1ed1i h\u00e0n tr\u00ean \u1ed1ng, h\u1ed9p Inox: Nguy\u00ean nh\u00e2n v\u00e0 c\u00e1ch kh\u1eafc ph\u1ee5c"},"content":{"rendered":"\n\n<div class=\"kk-star-ratings kksr-auto kksr-align-left kksr-valign-top\"\n    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19.2px;\">\n            <span class=\"kksr-muted\">\u0110\u00e1nh gi\u00e1<\/span>\n    <\/div>\n    <\/div>\n<div class=\"custom-toc\">\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_85 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/#Noi_dung_chinh\" >N\u1ed9i dung ch\u00ednh<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/#Cac_dang_nut_moi_han_Inox_thuong_gap_va_co_che\" >C\u00e1c d\u1ea1ng n\u1ee9t m\u1ed1i h\u00e0n Inox th\u01b0\u1eddng g\u1eb7p v\u00e0 c\u01a1 ch\u1ebf<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/#Vi_sao_ong_hop_Inox_de_nut_hon_tam_phang\" >V\u00ec sao \u1ed1ng, h\u1ed9p Inox d\u1ec5 n\u1ee9t h\u01a1n t\u1ea5m ph\u1eb3ng?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/#Chan_doan_nhanh_nguyen_nhan_theo_dau_hieu_hien_truong\" >Ch\u1ea9n \u0111o\u00e1n nhanh nguy\u00ean nh\u00e2n theo d\u1ea5u hi\u1ec7u hi\u1ec7n tr\u01b0\u1eddng<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/#Bien_phap_khac_phuc_va_phong_ngua_theo_nguyen_nhan\" >Bi\u1ec7n ph\u00e1p kh\u1eafc ph\u1ee5c v\u00e0 ph\u00f2ng ng\u1eeba theo nguy\u00ean nh\u00e2n<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/#1_Vat_lieu_va_kim_loai_dien\" >1) V\u1eadt li\u1ec7u v\u00e0 kim lo\u1ea1i \u0111i\u1ec1n<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/#2_Che_do_han_WPS_va_nhiet_vao\" >2) Ch\u1ebf \u0111\u1ed9 h\u00e0n (WPS) v\u00e0 nhi\u1ec7t v\u00e0o<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/#3_Bao_ve_khi_va_purge_mat_sau\" >3) B\u1ea3o v\u1ec7 kh\u00ed v\u00e0 purge m\u1eb7t sau<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/#4_Chuan_bi_mep_ga_lap_va_thiet_ke\" >4) Chu\u1ea9n b\u1ecb m\u00e9p, g\u00e1 l\u1eafp v\u00e0 thi\u1ebft k\u1ebf<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/#5_Kiem_soat_hydro_va_nhiet_cho_FerriticMartensitic\" >5) Ki\u1ec3m so\u00e1t hydro v\u00e0 nhi\u1ec7t cho Ferritic\/Martensitic<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/#6_Xu_ly_sau_han\" >6) X\u1eed l\u00fd sau h\u00e0n<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-12\" href=\"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/#7_Kiem_soat_moi_truong_van_hanh_SCC\" >7) Ki\u1ec3m so\u00e1t m\u00f4i tr\u01b0\u1eddng v\u1eadn h\u00e0nh (SCC)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-13\" href=\"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/#Thong_so_goi_y_khi_han_onghop_Inox_mong%E2%80%93trung_binh\" >Th\u00f4ng s\u1ed1 g\u1ee3i \u00fd khi h\u00e0n \u1ed1ng\/h\u1ed9p Inox m\u1ecfng\u2013trung b\u00ecnh<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-14\" href=\"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/#Quy_trinh_sua_chua_moi_han_bi_nut_thuc_hanh_xuong\" >Quy tr\u00ecnh s\u1eeda ch\u1eefa m\u1ed1i h\u00e0n b\u1ecb n\u1ee9t (th\u1ef1c h\u00e0nh x\u01b0\u1edfng)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-15\" href=\"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/#Case_thuc_te_ngan_Ong_304_day_12_mm_nut_duong_tam_sau_han_TIG\" >Case th\u1ef1c t\u1ebf ng\u1eafn: \u1ed0ng 304 d\u00e0y 1,2 mm n\u1ee9t \u0111\u01b0\u1eddng t\u00e2m sau h\u00e0n TIG<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-16\" href=\"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/#Tieu_chuan_va_muc_chap_nhan_tham_khao\" >Ti\u00eau chu\u1ea9n v\u00e0 m\u1ee9c ch\u1ea5p nh\u1eadn tham kh\u1ea3o<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-17\" href=\"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/#Bang_kiem_nhanh_truoc_%E2%80%93_trong_%E2%80%93_sau_khi_han\" >B\u1ea3ng ki\u1ec3m nhanh tr\u01b0\u1edbc \u2013 trong \u2013 sau khi h\u00e0n<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-18\" href=\"https:\/\/inoxcuongthinh.com\/nut-moi-han-tren-ong-hop-inox-nguyen-nhan-va-cach-khac-phuc\/#Tai_lieu_tham_khao\" >T\u00e0i li\u1ec7u tham kh\u1ea3o<\/a><\/li><\/ul><\/nav><\/div>\n<h3><span class=\"ez-toc-section\" id=\"Noi_dung_chinh\"><\/span>N\u1ed9i dung ch\u00ednh<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<ul>\n<li><a href=\"#toc-0-cac-dang-nut-moi-han-inox-thuong-gap-va-co-che\">C\u00e1c d\u1ea1ng n\u1ee9t m\u1ed1i h\u00e0n Inox th\u01b0\u1eddng g\u1eb7p v\u00e0 c\u01a1 ch\u1ebf<\/a><\/li>\n<li><a href=\"#toc-1-vi-sao-ong-hop-inox-de-nut-hon-tam-phang\">V\u00ec sao \u1ed1ng, h\u1ed9p Inox d\u1ec5 n\u1ee9t h\u01a1n t\u1ea5m ph\u1eb3ng?<\/a><\/li>\n<li><a href=\"#toc-2-chan-doan-nhanh-nguyen-nhan-theo-dau-hieu-hien-tru\">Ch\u1ea9n \u0111o\u00e1n nhanh nguy\u00ean nh\u00e2n theo d\u1ea5u hi\u1ec7u hi\u1ec7n tr\u01b0\u1eddng<\/a><\/li>\n<li><a href=\"#toc-3-bien-phap-khac-phuc-va-phong-ngua-theo-nguyen-nhan\">Bi\u1ec7n ph\u00e1p kh\u1eafc ph\u1ee5c v\u00e0 ph\u00f2ng ng\u1eeba theo nguy\u00ean nh\u00e2n<\/a><\/li>\n<li><a href=\"#toc-4-thong-so-goi-y-khi-han-onghop-inox-mongtrung-binh\">Th\u00f4ng s\u1ed1 g\u1ee3i \u00fd khi h\u00e0n \u1ed1ng\/h\u1ed9p Inox m\u1ecfng\u2013trung b\u00ecnh<\/a><\/li>\n<li><a href=\"#toc-5-quy-trinh-sua-chua-moi-han-bi-nut-thuc-hanh-xuong\">Quy tr\u00ecnh s\u1eeda ch\u1eefa m\u1ed1i h\u00e0n b\u1ecb n\u1ee9t (th\u1ef1c h\u00e0nh x\u01b0\u1edfng)<\/a><\/li>\n<li><a href=\"#toc-6-case-thuc-te-ngan-ong-304-day-12-mm-nut-duong-tam-\">Case th\u1ef1c t\u1ebf ng\u1eafn: \u1ed0ng 304 d\u00e0y 1,2 mm n\u1ee9t \u0111\u01b0\u1eddng t\u00e2m sau h\u00e0n TIG<\/a><\/li>\n<li><a href=\"#toc-7-tieu-chuan-va-muc-chap-nhan-tham-khao\">Ti\u00eau chu\u1ea9n v\u00e0 m\u1ee9c ch\u1ea5p nh\u1eadn tham kh\u1ea3o<\/a><\/li>\n<li><a href=\"#toc-8-bang-kiem-nhanh-truoc-trong-sau-khi-han\">B\u1ea3ng ki\u1ec3m nhanh tr\u01b0\u1edbc \u2013 trong \u2013 sau khi h\u00e0n<\/a><\/li>\n<li><a href=\"#toc-9-tai-lieu-tham-khao\">T\u00e0i li\u1ec7u tham kh\u1ea3o<\/a><\/li>\n<\/ul>\n<\/div>\n<p>Hi\u1ec7n t\u01b0\u1ee3ng n\u1ee9t m\u1ed1i h\u00e0n tr\u00ean \u1ed1ng, h\u1ed9p Inox g\u00e2y r\u00f2 r\u1ec9, gi\u1ea3m tu\u1ed5i th\u1ecd v\u00e0 chi ph\u00ed s\u1eeda ch\u1eefa l\u1edbn. B\u00e0i vi\u1ebft n\u00e0y ph\u00e2n t\u00edch \u0111\u1ea7y \u0111\u1ee7 nguy\u00ean nh\u00e2n \u0111i\u1ec3n h\u00ecnh (n\u1ee9t n\u00f3ng, n\u1ee9t l\u1ea1nh\/hydro, n\u1ee9t do \u0103n m\u00f2n \u1ee9ng su\u1ea5t, n\u1ee9t m\u1ecfi\u2026), c\u00e1ch ch\u1ea9n \u0111o\u00e1n v\u00e0 bi\u1ec7n ph\u00e1p kh\u1eafc ph\u1ee5c theo th\u1ef1c t\u1ebf x\u01b0\u1edfng gia c\u00f4ng \u1ed1ng\/h\u1ed9p m\u1ecfng \u0111\u1ebfn trung b\u00ecnh. Ch\u1ee7 \u0111\u1ec1 n\u00e0y l\u00e0 m\u1eaft x\u00edch quan tr\u1ecdng trong c\u1ea9m nang \u1ed1ng v\u00e0 h\u1ed9p Inox v\u00ec ch\u1ea5t l\u01b0\u1ee3ng m\u1ed1i h\u00e0n quy\u1ebft \u0111\u1ecbnh \u0111\u1ed9 k\u00edn, \u0111\u1ed9 b\u1ec1n v\u00e0 an to\u00e0n c\u00f4ng tr\u00ecnh.<\/p>\n<h2 id=\"toc-0-cac-dang-nut-moi-han-inox-thuong-gap-va-co-che\"><span class=\"ez-toc-section\" id=\"Cac_dang_nut_moi_han_Inox_thuong_gap_va_co_che\"><\/span>C\u00e1c d\u1ea1ng n\u1ee9t m\u1ed1i h\u00e0n Inox th\u01b0\u1eddng g\u1eb7p v\u00e0 c\u01a1 ch\u1ebf<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>&#8211; N\u1ee9t n\u00f3ng (solidification\/liquation cracking): xu\u1ea5t hi\u1ec7n khi kim lo\u1ea1i m\u1ed1i h\u00e0n c\u00f2n n\u00f3ng \u0111\u1ecf \u0111\u1ebfn g\u1ea7n nhi\u1ec7t \u0111\u1ed9 h\u00f3a r\u1eafn. V\u1edbi Inox Austenitic (304\/304L, 316\/316L), nguy c\u01a1 cao do c\u00e1c t\u1ea1p P, S, Si t\u1ea1o m\u00e0ng eutectic c\u00f3 nhi\u1ec7t \u0111\u1ed9 n\u00f3ng ch\u1ea3y th\u1ea5p b\u00e1m bi\u00ean h\u1ea1t; h\u00e0m l\u01b0\u1ee3ng ferrite delta qu\u00e1 th\u1ea5p c\u0169ng l\u00e0m t\u0103ng r\u1ee7i ro. D\u1ea5u hi\u1ec7u: n\u1ee9t d\u1ecdc theo t\u00e2m m\u1ed1i h\u00e0n (centerline), n\u1ee9t ch\u00e2n\/\u0111\u1ec9nh m\u1ed1i; th\u01b0\u1eddng xu\u1ea5t hi\u1ec7n ngay sau khi h\u00e0n ho\u1eb7c sau va \u0111\u1eadp nh\u1eb9. (TWI)<br \/>\n&#8211; N\u1ee9t l\u1ea1nh\/hydro: hi\u1ebfm \u1edf Austenitic nh\u01b0ng g\u1eb7p \u1edf Inox Martensitic (410, 420) v\u00e0 Ferritic (430) do t\u00f4i ngu\u1ed9i v\u00e0 hydro khu\u1ebfch t\u00e1n. D\u1ea5u hi\u1ec7u: n\u1ee9t tr\u1ec5 sau v\u00e0i gi\u1edd\u2013v\u00e0i ng\u00e0y, ti\u1ebfng \u201ct\u00e1ch\u201d nh\u1ecf, xu\u1ea5t hi\u1ec7n g\u1ea7n HAZ. (TWI)<br \/>\n&#8211; N\u1ee9t do \u0103n m\u00f2n \u1ee9ng su\u1ea5t clorua (SCC): x\u1ea3y ra trong v\u1eadn h\u00e0nh khi c\u00f3 ion Cl-, nhi\u1ec7t \u0111\u1ed9 th\u01b0\u1eddng >60\u00b0C v\u00e0 \u1ee9ng su\u1ea5t k\u00e9o d\u01b0 sau h\u00e0n. D\u1ea5u hi\u1ec7u: m\u1ea1ng n\u1ee9t t\u01a1, xu\u1ea5t hi\u1ec7n sau v\u00e0i tu\u1ea7n\u2013v\u00e0i th\u00e1ng, t\u1eadp trung v\u00f9ng HAZ v\u00e0 b\u1ec1 m\u1eb7t c\u00f3 \u201cheat tint\u201d. (Nickel Institute)<br \/>\n&#8211; N\u1ee9t m\u1ecfi: ph\u00e1t sinh \u1edf ch\u00e2n\/\u0111\u1ec9nh m\u1ed1i h\u00e0n t\u1ea1i k\u1ebft c\u1ea5u ch\u1ecbu rung \u0111\u1ed9ng; kh\u1edfi ph\u00e1t t\u1eeb khuy\u1ebft t\u1eadt vi m\u00f4 (underfill, lack of fusion).<br \/>\n&#8211; N\u1ee9t h\u1ed1 co (crater crack): do ng\u1eebng h\u1ed3 quang \u0111\u1ed9t ng\u1ed9t, co ng\u00f3t kh\u00f4ng \u0111\u01b0\u1ee3c b\u00f9; hay g\u1eb7p khi h\u00e0n TIG\/GMAW \u1edf \u1ed1ng m\u1ecfng.<br \/>\nL\u01b0u \u00fd: \u201cSugaring\u201d (oxy h\u00f3a m\u1eb7t sau khi h\u00e0n TIG kh\u00f4ng c\u00f3 purge) kh\u00f4ng ph\u1ea3i n\u1ee9t nh\u01b0ng l\u00e0m gi\u00f2n, gi\u1ea3m Cr, t\u1ea1o m\u1ea7m n\u1ee9t v\u00e0 \u0103n m\u00f2n sau n\u00e0y.<\/p>\n<h2 id=\"toc-1-vi-sao-ong-hop-inox-de-nut-hon-tam-phang\"><span class=\"ez-toc-section\" id=\"Vi_sao_ong_hop_Inox_de_nut_hon_tam_phang\"><\/span>V\u00ec sao \u1ed1ng, h\u1ed9p Inox d\u1ec5 n\u1ee9t h\u01a1n t\u1ea5m ph\u1eb3ng?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>&#8211; G\u00e1 l\u1eafp c\u1ee9ng v\u00e0 h\u00ecnh h\u1ecdc k\u00edn l\u00e0m t\u0103ng \u0111\u1ed9 k\u00ecm h\u00e3m co ng\u00f3t, t\u0103ng \u1ee9ng su\u1ea5t k\u00e9o d\u1ecdc m\u1ed1i h\u00e0n.<br \/>\n&#8211; \u1ed0ng\/h\u1ed9p m\u1ecfng (0,8\u20132,0 mm) d\u1ec5 qu\u00e1 nhi\u1ec7t, m\u00e9o, t\u1ea1o \u201cch\u1ed7 th\u1eaft\u201d v\u00e0 h\u1ed1 co.<br \/>\n&#8211; M\u1ed1i h\u00e0n k\u00edn c\u1ea7n b\u1ea3o v\u1ec7 m\u1eb7t sau; n\u1ebfu purge k\u00e9m (O2 cao), b\u1ec1 m\u1eb7t b\u1ecb oxy h\u00f3a, bi\u00ean h\u1ea1t y\u1ebfu.<br \/>\n&#8211; T\u00ednh d\u1ecb h\u01b0\u1edbng sau u\u1ed1n\/\u0111\u1ecbnh h\u00ecnh \u1ed1ng l\u00e0m t\u1eadp trung \u1ee9ng su\u1ea5t \u1edf \u0111\u01b0\u1eddng h\u00e0n d\u1ecdc khi ch\u1ecbu t\u1ea3i\/va \u0111\u1eadp.<\/p>\n<h2 id=\"toc-2-chan-doan-nhanh-nguyen-nhan-theo-dau-hieu-hien-tru\"><span class=\"ez-toc-section\" id=\"Chan_doan_nhanh_nguyen_nhan_theo_dau_hieu_hien_truong\"><\/span>Ch\u1ea9n \u0111o\u00e1n nhanh nguy\u00ean nh\u00e2n theo d\u1ea5u hi\u1ec7u hi\u1ec7n tr\u01b0\u1eddng<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>&#8211; N\u1ee9t xu\u1ea5t hi\u1ec7n ngay khi ngu\u1ed9i, ch\u1ea1y d\u1ecdc t\u00e2m m\u1ed1i TIG t\u1ef1 \u0111\u1ed9ng\/autogenous tr\u00ean 304\/316: nghi n\u1ee9t n\u00f3ng do FN qu\u00e1 th\u1ea5p, t\u1ed1c \u0111\u1ed9 cao, khe h\u1edf\/\u0111\u1ed9 k\u00ecm h\u00e3m l\u1edbn.<br \/>\n&#8211; N\u1ee9t sau 1\u20133 ng\u00e0y tr\u00ean 410\/430, kh\u00ed \u1ea9m, kim lo\u1ea1i ngu\u1ed9i nhanh: nghi n\u1ee9t l\u1ea1nh\/hydro; ki\u1ec3m tra quy tr\u00ecnh s\u1ea5y que\/d\u00e2y, ti\u1ec1n nhi\u1ec7t.<br \/>\n&#8211; N\u1ee9t d\u1ea1ng m\u1ea1ng t\u01a1 sau v\u00e0i th\u00e1ng v\u1eadn h\u00e0nh trong m\u00f4i tr\u01b0\u1eddng c\u00f3 mu\u1ed1i\/Cl-, nhi\u1ec7t >60\u00b0C: nghi SCC; ki\u1ec3m tra x\u1eed l\u00fd b\u1ec1 m\u1eb7t sau h\u00e0n v\u00e0 c\u1ea5p v\u1eadt li\u1ec7u (304 vs 316L).<br \/>\n&#8211; N\u1ee9t t\u1ea1i h\u1ed1 co cu\u1ed1i \u0111\u01b0\u1eddng h\u00e0n: do d\u1eebng h\u1ed3 quang \u0111\u1ed9t ng\u1ed9t, thi\u1ebfu l\u1ea5p h\u1ed1 co.<br \/>\n&#8211; N\u1ee9t t\u1ea1i g\u00f3c h\u1ed9p (toe\/fillet): li\u00ean quan thi\u1ebft k\u1ebf g\u00f3c s\u1eafc, th\u1ea5u k\u00e9m\/l\u1ec7ch m\u00e9p, \u1ee9ng su\u1ea5t t\u1eadp trung.<br \/>\nKi\u1ec3m tra khuy\u1ebfn ngh\u1ecb:<br \/>\n&#8211; NDT: th\u1ea9m th\u1ea5u m\u00e0u (PT) \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh \u0111\u1ed9 d\u00e0i n\u1ee9t; n\u1ed9i soi \u1ed1ng n\u1ebfu c\u1ea7n.<br \/>\n&#8211; \u0110o O2 khi purge: m\u1ee5c ti\u00eau <100 ppm cho TIG b\u00ean trong \u1ed1ng k\u00edn.\n- \u0110o ferrite FN m\u1ed1i h\u00e0n Austenitic (ferritscope) m\u1ee5c ti\u00eau FN ~3\u201310 \u0111\u1ec3 gi\u1ea3m n\u1ee9t n\u00f3ng.\n- Soi macro\/micro, ph\u00e2n t\u00edch th\u00e0nh ph\u1ea7n\/kh\u00ed n\u1ebfu x\u1ea3y ra h\u00e0ng lo\u1ea1t.\n\n\n\n<h2 id=\"toc-3-bien-phap-khac-phuc-va-phong-ngua-theo-nguyen-nhan\"><span class=\"ez-toc-section\" id=\"Bien_phap_khac_phuc_va_phong_ngua_theo_nguyen_nhan\"><\/span>Bi\u1ec7n ph\u00e1p kh\u1eafc ph\u1ee5c v\u00e0 ph\u00f2ng ng\u1eeba theo nguy\u00ean nh\u00e2n<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<h3><span class=\"ez-toc-section\" id=\"1_Vat_lieu_va_kim_loai_dien\"><\/span>1) V\u1eadt li\u1ec7u v\u00e0 kim lo\u1ea1i \u0111i\u1ec1n<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>&#8211; Ch\u1ecdn d\u00e2y\/que ph\u00f9 h\u1ee3p: 308L cho 304\/304L; 316L cho 316\/316L; 309L cho h\u00e0n d\u1ecb v\u1eadt li\u1ec7u. \u01afu ti\u00ean b\u1ea3n \u201cL\u201d carbon th\u1ea5p \u0111\u1ec3 h\u1ea1n ch\u1ebf nh\u1ea1y c\u1ea3m h\u00f3a (gi\u1ea3m nguy c\u01a1 SCC\/IGC). (AWS D1.6, Lincoln Electric)<br \/>\n&#8211; Ki\u1ec3m so\u00e1t ferrite delta: d\u00f9ng kim lo\u1ea1i \u0111i\u1ec1n c\u00f3 FN d\u1ef1 ki\u1ebfn 3\u201310 theo bi\u1ec3u \u0111\u1ed3 DeLong\/WRC-1992 \u0111\u1ec3 gi\u1ea3m n\u1ee9t n\u00f3ng; tr\u00e1nh TIG \u201cautogenous\u201d tr\u00ean m\u00e1c gi\u00e0u Ni\/Cr n\u1ebfu t\u1eebng n\u1ee9t.<br \/>\n&#8211; H\u1ea1n ch\u1ebf t\u1ea1p P, S; d\u00f9ng v\u1eadt li\u1ec7u \u0111\u1ea1t ASTM A554\/A312 chu\u1ea9n \u1ed1ng\/h\u1ed9p, y\u00eau c\u1ea7u ch\u1ee9ng ch\u1ec9 nhi\u1ec7t luy\u1ec7n\/kim t\u01b0\u01a1ng khi gia c\u00f4ng quan tr\u1ecdng.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"2_Che_do_han_WPS_va_nhiet_vao\"><\/span>2) Ch\u1ebf \u0111\u1ed9 h\u00e0n (WPS) v\u00e0 nhi\u1ec7t v\u00e0o<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>&#8211; Qu\u1ea3n l\u00fd nhi\u1ec7t v\u00e0o HI = (V x I x 60 x k) \/ (1000 x t\u1ed1c \u0111\u1ed9 h\u00e0n). V\u1edbi TIG l\u1ea5y k\u22480,6; \u01b0u ti\u00ean HI th\u1ea5p\u2013trung b\u00ecnh, dao \u0111\u1ed9ng m\u1ecf nh\u1ecf.<br \/>\n&#8211; Gi\u1edbi h\u1ea1n nhi\u1ec7t \u0111\u1ed9 gi\u1eefa c\u00e1c l\u1edbp v\u00e0 b\u1ec1 m\u1eb7t ph\u00f4i: Austenitic <150\u00b0C \u0111\u1ec3 h\u1ea1n ch\u1ebf nh\u1ea1y c\u1ea3m h\u00f3a; Ferritic\/Martensitic theo khuy\u1ebfn ngh\u1ecb nh\u00e0 s\u1ea3n xu\u1ea5t.\n- X\u1eed l\u00fd h\u1ed1 co: k\u00edch ho\u1ea1t ch\u1ee9c n\u0103ng crater fill\/slope-down; quay l\u1ea1i ch\u1ea5m k\u00edn mi\u1ec7ng h\u1ed1.\n- Tr\u00ecnh t\u1ef1 h\u00e0n gi\u1ea3m k\u00ecm h\u00e3m: back-step, chia \u0111o\u1ea1n \u0111\u1ed1i x\u1ee9ng; d\u00f9ng \u0111\u1ed3 g\u00e1 cho ph\u00e9p co ng\u00f3t t\u1ef1 do.\n\n\n\n<h3><span class=\"ez-toc-section\" id=\"3_Bao_ve_khi_va_purge_mat_sau\"><\/span>3) B\u1ea3o v\u1ec7 kh\u00ed v\u00e0 purge m\u1eb7t sau<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>&#8211; TIG\/GTAW: Argon 99,99%, 8\u201312 L\/ph\u00fat; \u1ed1ng\/h\u1ed9p k\u00edn c\u1ea7n back purging v\u1edbi O2 < 100 ppm; d\u00f9ng b\u0103ng g\u1ed1m\/gi\u1ea5y purge ho\u1eb7c n\u1eafp ch\u1eb7n m\u1ec1m, theo d\u00f5i b\u1eb1ng m\u00e1y \u0111o O2.\n- GMAW xung cho \u1ed1ng\/h\u1ed9p m\u1ecfng: kh\u00ed Ar+2%CO2 ho\u1eb7c Ar+1\u20132%O2 \u0111\u1ec3 gi\u1eef h\u1ed3 quang \u1ed5n \u0111\u1ecbnh, h\u1ea1n ch\u1ebf oxy h\u00f3a; l\u01b0u \u00fd kh\u00f4ng d\u00f9ng CO2 cao v\u1edbi Inox.\n- B\u1ea3o v\u1ec7 k\u00e9o \u0111u\u00f4i (trailing shield) cho m\u1ed1i d\u00e0i \u0111\u1ec3 tr\u00e1nh heat tint.\n\n\n\n<h3><span class=\"ez-toc-section\" id=\"4_Chuan_bi_mep_ga_lap_va_thiet_ke\"><\/span>4) Chu\u1ea9n b\u1ecb m\u00e9p, g\u00e1 l\u1eafp v\u00e0 thi\u1ebft k\u1ebf<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>&#8211; L\u00e0m s\u1ea1ch 2 b\u00ean m\u00e9p \u226520 mm: t\u1ea9y d\u1ea7u, b\u1ee5i, \u1ea9m; ch\u1ec9 d\u00f9ng b\u00e0n ch\u1ea3i\/n\u1ec9 chuy\u00ean d\u1ee5ng cho Inox.<br \/>\n&#8211; Khe h\u1edf v\u00e0 l\u1ec7ch m\u00e9p h\u1ee3p l\u00fd: \u1ed1ng\/h\u1ed9p m\u1ecfng \u01b0u ti\u00ean khe h\u1edf nh\u1ecf, fit-up s\u00e1t; d\u00f9ng backing\/copper chill bar \u0111\u1ec3 t\u1ea3n nhi\u1ec7t.<br \/>\n&#8211; Bo g\u00f3c h\u1ed9p n\u1ebfu c\u00f3 th\u1ec3; tr\u00e1nh g\u00f3c s\u1eafc t\u1eadp trung \u1ee9ng su\u1ea5t. B\u1ed1 tr\u00ed g\u00e2n\/t\u0103ng c\u1ee9ng h\u1ee3p l\u00fd gi\u1ea3m rung \u0111\u1ed9ng.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"5_Kiem_soat_hydro_va_nhiet_cho_FerriticMartensitic\"><\/span>5) Ki\u1ec3m so\u00e1t hydro v\u00e0 nhi\u1ec7t cho Ferritic\/Martensitic<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>&#8211; S\u1ea5y que\/d\u00e2y theo khuy\u1ebfn ngh\u1ecb; gi\u1eef kh\u00f4 kh\u00ed v\u00e0 \u1ed1ng d\u1eabn. Tr\u00e1nh h\u01a1i \u1ea9m b\u1ec1 m\u1eb7t.<br \/>\n&#8211; Ti\u1ec1n nhi\u1ec7t: 150\u2013250\u00b0C cho 410\/420 (theo WPS\/PQR); duy tr\u00ec gi\u1eefa c\u00e1c \u0111\u01b0\u1eddng h\u00e0n; ram gi\u1ea3m \u1ee9ng su\u1ea5t sau h\u00e0n khi y\u00eau c\u1ea7u.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"6_Xu_ly_sau_han\"><\/span>6) X\u1eed l\u00fd sau h\u00e0n<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>&#8211; T\u1ea9y g\u1ec9 \u2013 th\u1ee5 \u0111\u1ed9ng h\u00f3a: lo\u1ea1i b\u1ecf heat tint b\u1eb1ng gel axit nitric\/fluoric ho\u1eb7c gi\u1ea3i ph\u00e1p citric chuy\u00ean d\u1ee5ng; r\u1eeda s\u1ea1ch, trung h\u00f2a \u0111\u1ec3 ph\u1ee5c h\u1ed3i l\u1edbp th\u1ee5 \u0111\u1ed9ng Cr2O3, gi\u1ea3m nguy c\u01a1 SCC\/\u0103n m\u00f2n k\u1ebd. (Nickel Institute)<br \/>\n&#8211; M\u00e0i bo ch\u00e2n m\u1ed1i (toe dressing) ho\u1eb7c TIG remelt nh\u1eb9 cho k\u1ebft c\u1ea5u ch\u1ecbu m\u1ecfi.<br \/>\n&#8211; Kh\u00f4ng tr\u1ed9n d\u1ee5ng c\u1ee5 th\u00e9p carbon l\u00ean Inox (tr\u00e1nh nhi\u1ec5m s\u1eaft t\u1ef1 do).<\/p>\n<h3><span class=\"ez-toc-section\" id=\"7_Kiem_soat_moi_truong_van_hanh_SCC\"><\/span>7) Ki\u1ec3m so\u00e1t m\u00f4i tr\u01b0\u1eddng v\u1eadn h\u00e0nh (SCC)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>&#8211; Ch\u1ecdn v\u1eadt li\u1ec7u ph\u00f9 h\u1ee3p: 316L cho m\u00f4i tr\u01b0\u1eddng clorua nh\u1eb9; Duplex 2205 cho kh\u1eafc nghi\u1ec7t h\u01a1n. Gi\u1eef nhi\u1ec7t \u0111\u1ed9 th\u00e0nh \u1ed1ng <60\u00b0C khi c\u00f3 Cl- n\u1ebfu d\u00f9ng Austenitic chu\u1ea9n.\n- C\u00e1ch nhi\u1ec7t kh\u00f4, tr\u00e1nh \u1ea9m ng\u1ea5m mu\u1ed1i; thi\u1ebft k\u1ebf tho\u00e1t n\u01b0\u1edbc, tr\u00e1nh khe k\u1eb9t.\n- Gi\u1ea3m \u1ee9ng su\u1ea5t d\u01b0: tr\u00ecnh t\u1ef1 h\u00e0n t\u1ed1i \u01b0u; \u1edf nhi\u1ec7t \u0111\u1ed9 cao quan tr\u1ecdng c\u00f3 th\u1ec3 c\u00e2n nh\u1eafc \u1ee7 h\u00f2a tan (kh\u00f3 \u00e1p d\u1ee5ng cho k\u1ebft c\u1ea5u ho\u00e0n thi\u1ec7n).\n\n\n\n<h2 id=\"toc-4-thong-so-goi-y-khi-han-onghop-inox-mongtrung-binh\"><span class=\"ez-toc-section\" id=\"Thong_so_goi_y_khi_han_onghop_Inox_mong%E2%80%93trung_binh\"><\/span>Th\u00f4ng s\u1ed1 g\u1ee3i \u00fd khi h\u00e0n \u1ed1ng\/h\u1ed9p Inox m\u1ecfng\u2013trung b\u00ecnh<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>&#8211; TIG 1,0\u20131,5 mm: \u0111i\u1ec7n c\u1ef1c 1,6\u20132,4 mm (2% thori\/ceria), 45\u201385 A DCEN, Ar 8\u201310 L\/ph\u00fat; d\u00e2y 1,0\u20131,2 mm 308L\/316L; t\u1ed1c \u0111\u1ed9 150\u2013250 mm\/ph\u00fat; purge 5\u201310 L\/ph\u00fat \u0111\u1ebfn O2<100 ppm.\n- TIG 2,0\u20133,0 mm: 80\u2013120 A, Ar 10\u201312 L\/ph\u00fat; c\u00f3 th\u1ec3 v\u00e1t m\u00e9p nh\u1ecf n\u1ebfu y\u00eau c\u1ea7u th\u1ea5u ho\u00e0n to\u00e0n.\n- GMAW xung d\u00e2y 0,8\u20131,0 mm: kh\u00ed Ar+2%CO2, \u0111i\u1ec7n \u00e1p 18\u201323 V, d\u00f2ng trung b\u00ecnh 80\u2013140 A; c\u00e0i \u0111\u1eb7t xung theo nh\u00e0 SX m\u00e1y h\u00e0n \u0111\u1ec3 gi\u1ea3m nhi\u1ec7t v\u00e0o v\u00e0 b\u1eafn t\u00f3e.\nL\u01b0u \u00fd: Th\u00f4ng s\u1ed1 ch\u1ec9 l\u00e0 \u0111i\u1ec3m kh\u1edfi \u0111\u1ea7u; b\u1eaft bu\u1ed9c l\u1eadp WPS\/PQR theo AWS D1.6 ho\u1eb7c ASME IX cho s\u1ea3n xu\u1ea5t h\u00e0ng lo\u1ea1t.\n\n\n\n<h2 id=\"toc-5-quy-trinh-sua-chua-moi-han-bi-nut-thuc-hanh-xuong\"><span class=\"ez-toc-section\" id=\"Quy_trinh_sua_chua_moi_han_bi_nut_thuc_hanh_xuong\"><\/span>Quy tr\u00ecnh s\u1eeda ch\u1eefa m\u1ed1i h\u00e0n b\u1ecb n\u1ee9t (th\u1ef1c h\u00e0nh x\u01b0\u1edfng)<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>1) C\u00f4 l\u1eadp v\u00e0 \u0111\u00e1nh d\u1ea5u: v\u1ec7 sinh, PT \u0111\u1ec3 khoanh v\u00f9ng; n\u1ebfu \u1ed1ng \u00e1p l\u1ef1c, gi\u1ea3m \u00e1p\/tho\u00e1t s\u1ea1ch m\u00f4i ch\u1ea5t.<br \/>\n2) M\u00e0i m\u1edf v\u1ebft n\u1ee9t d\u1ea1ng r\u00e3nh ch\u1eef U, v\u01b0\u1ee3t qu\u00e1 \u0111\u1ea7u n\u1ee9t t\u1ed1i thi\u1ec3u 10\u201315 mm; tr\u00e1nh m\u00e0i qu\u00e1 m\u1ecfng th\u00e0nh \u1ed1ng.<br \/>\n3) L\u00e0m s\u1ea1ch k\u1ef9, purge m\u1eb7t sau n\u1ebfu th\u1ea5u k\u00edn; \u0111i\u1ec1u ch\u1ec9nh WPS theo nguy\u00ean nh\u00e2n g\u1ed1c (v\u00ed d\u1ee5 th\u00eam 308L \u0111\u1ec3 t\u0103ng FN, gi\u1ea3m nhi\u1ec7t v\u00e0o).<br \/>\n4) H\u00e0n \u0111\u1eafp ph\u1ee5c h\u1ed3i; x\u1eed l\u00fd h\u1ed1 co; ki\u1ec3m so\u00e1t interpass.<br \/>\n5) NDT l\u1ea1i (VT\/PT; n\u1ebfu y\u00eau c\u1ea7u RT\/UT v\u1edbi th\u00e0nh d\u00e0y).<br \/>\n6) T\u1ea9y \u2013 th\u1ee5 \u0111\u1ed9ng h\u00f3a; nghi\u1ec7m thu theo m\u1ee9c ch\u1ea5t l\u01b0\u1ee3ng \u0111\u00e3 x\u00e1c \u0111\u1ecbnh (ISO 5817).<br \/>\nGhi nh\u1edb: Theo ti\u00eau chu\u1ea9n, m\u1ecdi d\u1ea1ng \u201ccrack\u201d \u0111\u1ec1u kh\u00f4ng \u0111\u01b0\u1ee3c ch\u1ea5p nh\u1eadn (ISO 5817; AWS D1.6).<\/p>\n<h2 id=\"toc-6-case-thuc-te-ngan-ong-304-day-12-mm-nut-duong-tam-\"><span class=\"ez-toc-section\" id=\"Case_thuc_te_ngan_Ong_304_day_12_mm_nut_duong_tam_sau_han_TIG\"><\/span>Case th\u1ef1c t\u1ebf ng\u1eafn: \u1ed0ng 304 d\u00e0y 1,2 mm n\u1ee9t \u0111\u01b0\u1eddng t\u00e2m sau h\u00e0n TIG<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>&#8211; Hi\u1ec7n t\u01b0\u1ee3ng: n\u1ee9t ngay khi ngu\u1ed9i, ch\u1ea1y d\u1ecdc t\u00e2m m\u1ed1i h\u00e0n d\u1ecdc \u1ed1ng, h\u00e0n TIG kh\u00f4ng d\u00f9ng d\u00e2y (autogenous).<br \/>\n&#8211; Ph\u00e2n t\u00edch: m\u1ed1i h\u00e0n ho\u00e0n to\u00e0n Austenitic, FN\u22480 \u2192 n\u1ee9t n\u00f3ng; t\u1ed1c \u0111\u1ed9 cao, khe h\u1edf kh\u00f4ng \u0111\u1ec1u.<br \/>\n&#8211; Kh\u1eafc ph\u1ee5c: th\u00eam d\u00e2y 308L \u00d81,0 mm \u0111\u1ec3 \u0111\u1ea1t FN 3\u20136; gi\u1ea3m 10\u201315% t\u1ed1c \u0111\u1ed9 h\u00e0n; b\u1eadt crater fill; purge m\u1eb7t sau \u0111\u1ebfn O2<100 ppm; k\u1ebft qu\u1ea3: h\u1ebft n\u1ee9t, b\u1ec1 m\u1eb7t s\u00e1ng, \u0111\u1ea1t PT c\u1ea5p B theo ISO 5817.\n\n\n\n<h2 id=\"toc-7-tieu-chuan-va-muc-chap-nhan-tham-khao\"><span class=\"ez-toc-section\" id=\"Tieu_chuan_va_muc_chap_nhan_tham_khao\"><\/span>Ti\u00eau chu\u1ea9n v\u00e0 m\u1ee9c ch\u1ea5p nh\u1eadn tham kh\u1ea3o<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>&#8211; ISO 5817: H\u00e0n n\u00f3ng ch\u1ea3y \u2013 C\u1ea5p ch\u1ea5t l\u01b0\u1ee3ng c\u1ee7a khuy\u1ebft t\u1eadt. M\u1ecdi v\u1ebft n\u1ee9t: kh\u00f4ng cho ph\u00e9p \u1edf t\u1ea5t c\u1ea3 c\u1ea5p (B, C, D).<br \/>\n&#8211; AWS D1.6\/D1.6M: Structural Welding Code \u2013 Stainless Steel. Y\u00eau c\u1ea7u WPS\/PQR; cracks = reject.<br \/>\n&#8211; ASME Section IX: Quy \u0111\u1ecbnh th\u00ed nghi\u1ec7m quy tr\u00ecnh h\u00e0n (PQR) v\u00e0 th\u00f4ng s\u1ed1 WPS d\u00f9ng cho s\u1ea3n xu\u1ea5t l\u1eb7p l\u1ea1i.<\/p>\n<h2 id=\"toc-8-bang-kiem-nhanh-truoc-trong-sau-khi-han\"><span class=\"ez-toc-section\" id=\"Bang_kiem_nhanh_truoc_%E2%80%93_trong_%E2%80%93_sau_khi_han\"><\/span>B\u1ea3ng ki\u1ec3m nhanh tr\u01b0\u1edbc \u2013 trong \u2013 sau khi h\u00e0n<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Tr\u01b0\u1edbc khi h\u00e0n<br \/>\n&#8211; V\u1eadt li\u1ec7u \u0111\u00fang m\u00e1c; ch\u1ee9ng ch\u1ec9 \u0111\u1ea1t chu\u1ea9n; b\u1ec1 m\u1eb7t s\u1ea1ch, kh\u00f4.<br \/>\n&#8211; D\u00e2y\/que \u0111\u00fang lo\u1ea1i (308L\/316L\u2026), h\u1ea1n t\u1ea1p P, S; FN d\u1ef1 ki\u1ebfn ph\u00f9 h\u1ee3p.<br \/>\n&#8211; Fit-up ch\u1eb7t, g\u00e1 l\u1eafp h\u1ea1n ch\u1ebf k\u00ecm h\u00e3m; chu\u1ea9n b\u1ecb purge cho \u1ed1ng k\u00edn.<\/p>\n<p>Trong khi h\u00e0n<br \/>\n&#8211; \u0110i\u1ec1u ch\u1ec9nh d\u00f2ng\/\u00e1p, t\u1ed1c \u0111\u1ed9 \u0111\u1ec3 gi\u1eef nhi\u1ec7t v\u00e0o th\u1ea5p\u2013trung b\u00ecnh; ki\u1ec3m so\u00e1t interpass <150\u00b0C (Austenitic).  \n- Purge \u0111\u1ebfn O2<100 ppm; b\u1ea3o v\u1ec7 k\u00e9o \u0111u\u00f4i; l\u1ea5p k\u00edn h\u1ed1 co.  \n- Theo d\u00f5i b\u1eafn t\u00f3e, heat tint; hi\u1ec7u ch\u1ec9nh ngay khi th\u1ea5y \u201c\u0111\u01b0\u1eddng th\u1eaft\u201d ho\u1eb7c h\u1ed3 quang b\u1ea5t \u1ed5n.\n\nSau khi h\u00e0n\n- NDT VT\/PT; s\u1eeda ch\u1eefa ngay khuy\u1ebft t\u1eadt; t\u1ea9y \u2013 th\u1ee5 \u0111\u1ed9ng h\u00f3a.  \n- Ghi bi\u00ean b\u1ea3n th\u00f4ng s\u1ed1, c\u1eadp nh\u1eadt WPS n\u1ebfu c\u00f3 \u0111i\u1ec1u ch\u1ec9nh; l\u1eadp k\u1ebf ho\u1ea1ch ki\u1ec3m tra \u0111\u1ecbnh k\u1ef3 v\u1edbi c\u00f4ng tr\u00ecnh c\u00f3 Cl-.\n\n\n\n<h2 id=\"toc-9-tai-lieu-tham-khao\"><span class=\"ez-toc-section\" id=\"Tai_lieu_tham_khao\"><\/span>T\u00e0i li\u1ec7u tham kh\u1ea3o<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>&#8211; The Welding Institute (TWI): Solidification cracking in austenitic stainless steel weld metals; Hydrogen cracking in steels; Guidance on purge and heat tint. https:\/\/www.twi-global.com<br \/>\n&#8211; AWS D1.6\/D1.6M: Structural Welding Code \u2013 Stainless Steel. American Welding Society.<br \/>\n&#8211; ASME Section IX: Qualification Standard for Welding and Brazing Procedures, Welders, Brazers.<br \/>\n&#8211; ISO 5817: Welding \u2013 Fusion-welded joints in steel, nickel, titanium and their alloys \u2013 Quality levels.<br \/>\n&#8211; Nickel Institute: Guidelines for chloride stress corrosion cracking of austenitic stainless steels. https:\/\/www.nickelinstitute.org<br \/>\n&#8211; Lincoln Electric\/ESAB Knowledge Center: Stainless steel filler selection and ferrite control.<\/p>\n<p>K\u1ebft lu\u1eadn<br \/>\n&#8211; N\u1ee9t m\u1ed1i h\u00e0n tr\u00ean \u1ed1ng, h\u1ed9p Inox ch\u1ee7 y\u1ebfu do n\u1ee9t n\u00f3ng (Austenitic), n\u1ee9t l\u1ea1nh\/hydro (Martensitic\/Ferritic), SCC trong m\u00f4i tr\u01b0\u1eddng Cl-, v\u00e0 n\u1ee9t do h\u1ed1 co\/m\u1ecfi.<br \/>\n&#8211; C\u1ed1t l\u00f5i ph\u00f2ng ng\u1eeba: ch\u1ecdn \u0111\u00fang v\u1eadt li\u1ec7u \u2013 kim lo\u1ea1i \u0111i\u1ec1n (\u01b0u ti\u00ean \u201cL\u201d, FN 3\u201310), ki\u1ec3m so\u00e1t nhi\u1ec7t v\u00e0o v\u00e0 purge m\u1eb7t sau, fit-up t\u1ed1t, x\u1eed l\u00fd b\u1ec1 m\u1eb7t sau h\u00e0n, v\u00e0 thi\u1ebft k\u1ebf gi\u1ea3m \u1ee9ng su\u1ea5t.<br \/>\n&#8211; Khi \u0111\u00e3 n\u1ee9t, c\u1ea7n m\u00e0i m\u1edf \u2013 h\u00e0n ph\u1ee5c h\u1ed3i theo WPS t\u1ed1i \u01b0u v\u00e0 ki\u1ec3m tra NDT; m\u1ecdi v\u1ebft n\u1ee9t \u0111\u1ec1u kh\u00f4ng ch\u1ea5p nh\u1eadn theo ISO 5817\/AWS D1.6.<br \/>\n\u0110\u1ec3 \u0111\u01b0\u1ee3c t\u01b0 v\u1ea5n quy tr\u00ecnh h\u00e0n t\u1ed1i \u01b0u cho \u1ed1ng, h\u1ed9p Inox v\u00e0 nh\u1eadn b\u00e1o gi\u00e1 t\u1ed1t, vui l\u00f2ng 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>Gi\u1ea3i m\u00e3 n\u1ee9t m\u1ed1i h\u00e0n tr\u00ean \u1ed1ng, h\u1ed9p Inox: nh\u1eadn di\u1ec7n n\u1ee9t n\u00f3ng, n\u1ee9t l\u1ea1nh v\u00e0 SCC; nguy\u00ean nh\u00e2n do v\u1eadt li\u1ec7u, ch\u1ebf \u0111\u1ed9, kh\u00ed b\u1ea3o v\u1ec7; c\u00e1ch kh\u1eafc ph\u1ee5c chu\u1ea9n x\u01b0\u1edfng.<\/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-2121","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\/2121","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=2121"}],"version-history":[{"count":0,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/posts\/2121\/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=2121"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/categories?post=2121"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/tags?post=2121"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}