{"id":3783,"date":"2026-05-10T01:18:11","date_gmt":"2026-05-10T01:18:11","guid":{"rendered":"https:\/\/productionscrews.com\/uns-thread\/"},"modified":"2026-05-10T01:19:38","modified_gmt":"2026-05-10T01:19:38","slug":"uns-thread","status":"publish","type":"post","link":"https:\/\/productionscrews.com\/vi\/uns-thread\/","title":{"rendered":"H\u01b0\u1edbng D\u1eabn \u0110\u1ea7y \u0110\u1ee7 V\u1ec1 Ren UNS: Th\u00f4ng S\u1ed1 K\u1ef9 Thu\u1eadt, B\u1ea3ng Tra &amp; \u1ee8ng D\u1ee5ng"},"content":{"rendered":"<p class=\"direct-answer\"><strong>Ren UNS (Unified National Special) l\u00e0 lo\u1ea1i ren \u0111\u1eb7c bi\u1ec7t v\u1edbi b\u01b0\u1edbc ren kh\u00f4ng ti\u00eau chu\u1ea9n v\u1ec1 s\u1ef1 k\u1ebft h\u1ee3p gi\u1eefa \u0111\u01b0\u1eddng k\u00ednh v\u00e0 b\u01b0\u1edbc ren, \u0111\u01b0\u1ee3c quy \u0111\u1ecbnh b\u1edfi ASME B1.1, s\u1eed d\u1ee5ng khi c\u00e1c b\u01b0\u1edbc ren ti\u00eau chu\u1ea9n UNC ho\u1eb7c UNF kh\u00f4ng \u0111\u00e1p \u1ee9ng \u0111\u01b0\u1ee3c y\u00eau c\u1ea7u thi\u1ebft k\u1ebf c\u1ee5 th\u1ec3.<\/strong><\/p>\n<p><img decoding=\"async\" alt=\"Ren UNS \u2014 minh h\u1ecda ch\u00ednh th\u1ec3 hi\u1ec7n c\u00e1c v\u00f2ng ren bulong gia c\u00f4ng ch\u00ednh x\u00e1c v\u1edbi c\u00e1c k\u00fd hi\u1ec7u \u0111o l\u01b0\u1eddng\" src=\"https:\/\/productionscrews.com\/wp-content\/uploads\/2026\/05\/uns-thread-hero.png\" \/><\/p>\n<p>M\u1ed7i th\u1ee3 c\u01a1 kh\u00ed cu\u1ed1i c\u00f9ng c\u0169ng s\u1ebd g\u1eb7p ph\u1ea3i t\u00ecnh hu\u1ed1ng m\u00e0 c\u00e1c b\u01b0\u1edbc ren ti\u00eau chu\u1ea9n \u0111\u01a1n gi\u1ea3n l\u00e0 kh\u00f4ng ph\u00f9 h\u1ee3p. Ch\u1ed1t c\u1ea7n ph\u1ea3i ch\u1eafc ch\u1eafn h\u01a1n so v\u1edbi ren th\u00f4 cho ph\u00e9p, nh\u01b0ng \u0111\u1ed9 d\u00e0y th\u00e0nh l\u1ea1i kh\u00f4ng \u0111\u1ee7 cho ren m\u1ecbn. Ho\u1eb7c m\u1ed9t chi ti\u1ebft c\u0169 \u0111\u00e3 c\u00f3 s\u1eb5n y\u00eau c\u1ea7u k\u00edch th\u01b0\u1edbc kh\u00f4ng xu\u1ea5t hi\u1ec7n trong b\u1ea5t k\u1ef3 b\u1ea3ng UNC ho\u1eb7c UNF ti\u00eau chu\u1ea9n n\u00e0o. \u0110\u00f3 ch\u00ednh l\u00e0 l\u00fac <strong>Ren UNS<\/strong> ph\u00e1t huy t\u00e1c d\u1ee5ng \u2014 v\u00e0 hi\u1ec3u r\u00f5 v\u1ec1 n\u00f3 c\u00f3 th\u1ec3 gi\u00fap b\u1ea1n tr\u00e1nh \u0111\u01b0\u1ee3c nh\u1eefng sai l\u1ec7ch t\u1ed1n k\u00e9m, lo\u1ea1i b\u1ecf chi ti\u1ebft v\u00e0 tr\u00ec ho\u00e3n.<\/p>\n<p>H\u01b0\u1edbng d\u1eabn n\u00e0y bao g\u1ed3m t\u1ea5t c\u1ea3: ren UNS l\u00e0 g\u00ec, ch\u00fang kh\u00e1c g\u00ec so v\u1edbi c\u00e1c lo\u1ea1i ren Unified kh\u00e1c, b\u1ea3ng k\u00edch th\u01b0\u1edbc \u0111\u1ea7y \u0111\u1ee7, \u1ee9ng d\u1ee5ng th\u1ef1c t\u1ebf trong ng\u00e0nh v\u00e0 gi\u1ea3i \u0111\u00e1p m\u1ecdi th\u1eafc m\u1eafc m\u00e0 th\u1ee3 c\u01a1 kh\u00ed v\u00e0 k\u1ef9 s\u01b0 th\u01b0\u1eddng g\u1eb7p. Sau khi \u0111\u1ecdc xong, b\u1ea1n s\u1ebd c\u00f3 th\u1ec3 \u0111\u1ecdc k\u00fd hi\u1ec7u ren UNS, x\u00e1c \u0111\u1ecbnh \u0111\u00fang c\u1ea5p dung sai, ch\u1ecdn mua ch\u1ed1t \u0111\u00fang chu\u1ea9n v\u00e0 tr\u00e1nh \u0111\u01b0\u1ee3c nh\u1eefng l\u1ed7i m\u00e0 ngay c\u1ea3 c\u00e1c x\u01b0\u1edfng kinh nghi\u1ec7m c\u0169ng d\u1ec5 m\u1eafc ph\u1ea3i.<\/p>\n<hr \/>\n<h2>Ren UNS L\u00e0 G\u00ec?<\/h2>\n<p><strong>Ren UNS \u2014 Unified National Special \u2014 l\u00e0 nh\u00f3m t\u1ed5ng h\u1ee3p trong ti\u00eau chu\u1ea9n ren Unified cho c\u00e1c t\u1ed5 h\u1ee3p kh\u00f4ng thu\u1ed9c UNC, UNF ho\u1eb7c UNEF.<\/strong><\/p>\n<p>H\u1ec7 th\u1ed1ng ren Unified National, \u0111\u01b0\u1ee3c \u0111\u1ecbnh ngh\u0129a trong <a href=\"https:\/\/www.asme.org\/codes-standards\/find-codes-standards\/b1-1-unified-inch-screw-threads-un-and-unr-thread-form\" target=\"_blank\" rel=\"noopener\">ASME B1.1<\/a>, ph\u00e2n lo\u1ea1i ren v\u00edt th\u00e0nh c\u00e1c d\u00e3y d\u1ef1a tr\u00ean \u0111\u01b0\u1eddng k\u00ednh v\u00e0 b\u01b0\u1edbc ren (s\u1ed1 ren tr\u00ean m\u1ed9t inch, TPI):<\/p>\n<ul>\n<li><strong>UNC<\/strong> (Unified National Coarse) \u2014 lo\u1ea1i ren ph\u1ed5 bi\u1ebfn nh\u1ea5t d\u00f9ng cho m\u1ee5c \u0111\u00edch chung<\/li>\n<li><strong>UNF<\/strong> (Unified National Fine) \u2014 nhi\u1ec1u ren tr\u00ean m\u1ed9t inch h\u01a1n, d\u00f9ng khi c\u1ea7n ch\u1ed1ng rung ho\u1eb7c \u0111i\u1ec1u ch\u1ec9nh tinh<\/li>\n<li><strong>UNEF<\/strong> (Unified National Extra Fine) \u2014 d\u00e3y ren m\u1ecbn nh\u1ea5t cho c\u00e1c \u1ee9ng d\u1ee5ng th\u00e0nh m\u1ecfng<\/li>\n<li><strong>UNS<\/strong> (Unified National Special) \u2014 t\u1ea5t c\u1ea3 c\u00e1c lo\u1ea1i c\u00f2n l\u1ea1i s\u1eed d\u1ee5ng h\u00ecnh d\u1ea1ng ren Unified nh\u01b0ng c\u00f3 b\u01b0\u1edbc ren kh\u00f4ng n\u1eb1m trong c\u00e1c d\u00e3y tr\u00ean<\/li>\n<\/ul>\n<p>Theo <a href=\"https:\/\/en.wikipedia.org\/wiki\/Unified_Thread_Standard\" target=\"_blank\" rel=\"noopener\">B\u00e0i vi\u1ebft tr\u00ean Wikipedia v\u1ec1 Ti\u00eau Chu\u1ea9n Ren Unified<\/a>, k\u00fd hi\u1ec7u UNS \u00e1p d\u1ee5ng cho \u201cc\u00e1c ren c\u00f3 \u0111\u01b0\u1eddng k\u00ednh, b\u01b0\u1edbc ren ho\u1eb7c chi\u1ec1u d\u00e0i \u0103n kh\u1edbp \u0111\u1eb7c bi\u1ec7t\u201d nh\u01b0ng v\u1eabn tu\u00e2n theo h\u00ecnh d\u1ea1ng ren Unified ti\u00eau chu\u1ea9n. H\u00ecnh d\u1ea1ng ren \u2014 g\u00f3c 60\u00b0, \u0111\u1ec9nh v\u00e0 \u0111\u00e1y ph\u1eb3ng \u2014 gi\u1ed1ng h\u1ec7t UNC, UNF v\u00e0 UNEF. Ch\u1ec9 c\u00f3 b\u01b0\u1edbc ren l\u00e0 \u0111\u1eb7c bi\u1ec7t.<\/p>\n<h3>H\u00ecnh D\u1ea1ng Ren M\u00e0 UNS Chia S\u1ebb V\u1edbi T\u1ea5t C\u1ea3 C\u00e1c Lo\u1ea1i Ren UN<\/h3>\n<p>H\u1ed3 s\u01a1 ren th\u1ed1ng nh\u1ea5t \u0111\u01b0\u1ee3c x\u00e1c \u0111\u1ecbnh b\u1edfi d\u1ea1ng ch\u1eef V \u0111\u1ed1i x\u1ee9ng 60\u00b0. C\u1ea3 ren ngo\u00e0i (bu l\u00f4ng) v\u00e0 ren trong (\u0111ai \u1ed1c) \u0111\u1ec1u s\u1eed d\u1ee5ng c\u00f9ng m\u1ed9t h\u00ecnh h\u1ecdc c\u01a1 b\u1ea3n:<\/p>\n<ul>\n<li><strong>G\u00f3c bao g\u1ed3m:<\/strong> G\u00f3c 60\u00b0<\/li>\n<li><strong>\u0110\u1ec9nh ren:<\/strong> ph\u1eb3ng ho\u1eb7c bo tr\u00f2n (bo tr\u00f2n tr\u00ean bi\u1ebfn th\u1ec3 UNR cho c\u00e1c \u1ee9ng d\u1ee5ng ch\u1ecbu m\u1ecfi cao)<\/li>\n<li><strong>Ch\u00e2n ren:<\/strong> ph\u1eb3ng ho\u1eb7c bo tr\u00f2n<\/li>\n<li><strong>B\u01b0\u1edbc ren (P):<\/strong> kho\u1ea3ng c\u00e1ch t\u1eeb m\u1ed9t \u0111\u1ec9nh ren \u0111\u1ebfn \u0111\u1ec9nh ren ti\u1ebfp theo, \u0111o b\u1eb1ng inch (= 1 \u00f7 s\u1ed1 ren tr\u00ean inch)<\/li>\n<\/ul>\n<p>V\u00ec ren UNS c\u00f3 c\u00f9ng h\u00ecnh d\u1ea1ng v\u1edbi UNC v\u00e0 UNF, c\u00e1c d\u1ee5ng c\u1ee5 \u0111o v\u00e0 ki\u1ec3m tra \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf cho d\u1ea1ng ren Th\u1ed1ng nh\u1ea5t \u0111\u1ec1u s\u1eed d\u1ee5ng \u0111\u01b0\u1ee3c cho ren UNS. S\u1ef1 kh\u00e1c bi\u1ec7t ch\u1ec9 n\u1eb1m \u1edf <em>n\u00e0o<\/em> b\u01b0\u1edbc ren \u0111\u01b0\u1ee3c c\u1eaft cho m\u1ed9t \u0111\u01b0\u1eddng k\u00ednh nh\u1ea5t \u0111\u1ecbnh.<\/p>\n<h3>S\u1ef1 kh\u00e1c bi\u1ec7t gi\u1eefa UNS v\u00e0 ren UN ti\u00eau chu\u1ea9n<\/h3>\n<p>\u0110i\u1ec3m kh\u00e1c bi\u1ec7t ch\u00ednh l\u00e0 <strong>chu\u1ea9n h\u00f3a b\u01b0\u1edbc ren t\u1ea1i m\u1ed9t \u0111\u01b0\u1eddng k\u00ednh nh\u1ea5t \u0111\u1ecbnh.<\/strong> \u0110\u1ed1i v\u1edbi b\u1ea5t k\u1ef3 \u0111\u01b0\u1eddng k\u00ednh n\u00e0o, UNC quy \u0111\u1ecbnh ch\u00ednh x\u00e1c m\u1ed9t b\u01b0\u1edbc ren, UNF quy \u0111\u1ecbnh ch\u00ednh x\u00e1c m\u1ed9t b\u01b0\u1edbc, v\u00e0 UNEF c\u0169ng v\u1eady. UNS kh\u00f4ng c\u00f3 b\u01b0\u1edbc ren c\u1ed1 \u0111\u1ecbnh \u2014 l\u00e0 b\u1ea5t k\u1ef3 b\u01b0\u1edbc n\u00e0o m\u00e0 nh\u00e0 thi\u1ebft k\u1ebf ch\u1ec9 \u0111\u1ecbnh, mi\u1ec5n l\u00e0 s\u1eed d\u1ee5ng d\u1ea1ng Th\u1ed1ng nh\u1ea5t v\u00e0 kh\u00f4ng tr\u00f9ng v\u1edbi UNC, UNF ho\u1eb7c UNEF.<\/p>\n<p>Trong th\u1ef1c t\u1ebf, ren UNS xu\u1ea5t hi\u1ec7n trong b\u1ed1n tr\u01b0\u1eddng h\u1ee3p:<\/p>\n<ol>\n<li><strong>Ph\u1ee5 t\u00f9ng c\u0169\/n\u00e2ng c\u1ea5p<\/strong> \u2014 c\u00e1c thi\u1ebft k\u1ebf c\u0169 c\u00f3 tr\u01b0\u1edbc khi c\u00f3 c\u00e1c d\u00f2ng ti\u00eau chu\u1ea9n v\u00e0 ch\u01b0a bao gi\u1edd \u0111\u01b0\u1ee3c c\u1eadp nh\u1eadt<\/li>\n<li><strong>Y\u00eau c\u1ea7u v\u1ec1 \u0111\u1ed9 b\u1ec1n<\/strong> \u2014 c\u1ea7n nhi\u1ec1u ren tr\u00ean m\u1ed7i inch h\u01a1n UNC nh\u01b0ng \u00edt h\u01a1n UNF cho m\u1ed9t \u0111\u01b0\u1eddng k\u00ednh c\u1ee5 th\u1ec3<\/li>\n<li><strong>H\u1ea1n ch\u1ebf th\u00e0nh m\u1ecfng<\/strong> \u2014 m\u1ed9t \u1ed1ng ho\u1eb7c v\u1eadt \u0111\u00fac m\u00e0 b\u01b0\u1edbc ren ti\u00eau chu\u1ea9n qu\u00e1 nh\u1ecf s\u1ebd khi\u1ebfn v\u1eadt li\u1ec7u t\u1eeb ch\u00e2n ren \u0111\u1ebfn th\u00e0nh kh\u00f4ng \u0111\u1ee7<\/li>\n<li><strong>Y\u00eau c\u1ea7u v\u1ec1 kh\u1ea3 n\u0103ng thay th\u1ebf<\/strong> \u2014 kh\u1edbp v\u1edbi ren \u0111\u1ed9c quy\u1ec1n t\u1eeb nh\u00e0 s\u1ea3n xu\u1ea5t kh\u00e1c c\u00f3 b\u01b0\u1edbc ren kh\u00f4ng ti\u00eau chu\u1ea9n<\/li>\n<\/ol>\n<p><strong>B\u1ea2NG 1 \u2014 So s\u00e1nh UNC vs UNF vs UNEF vs UNS<\/strong><\/p>\n<table>\n<thead>\n<tr>\n<th>\u0110\u1eb7c \u0111i\u1ec3m<\/th>\n<th>UNC<\/th>\n<th>UNF<\/th>\n<th>UNEF<\/th>\n<th>UNS<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>T\u00ean \u0111\u1ea7y \u0111\u1ee7<\/td>\n<td>Unified National Coarse<\/td>\n<td>Ren h\u1ec7 th\u1ed1ng th\u1ed1ng nh\u1ea5t m\u1ecbn<\/td>\n<td>Ren c\u1ef1c m\u1ecbn qu\u1ed1c gia th\u1ed1ng nh\u1ea5t<\/td>\n<td>Ren \u0111\u1eb7c bi\u1ec7t qu\u1ed1c gia th\u1ed1ng nh\u1ea5t<\/td>\n<\/tr>\n<tr>\n<td>B\u01b0\u1edbc Ren<\/td>\n<td>Ti\u00eau chu\u1ea9n h\u00f3a theo \u0111\u01b0\u1eddng k\u00ednh<\/td>\n<td>Ti\u00eau chu\u1ea9n h\u00f3a theo \u0111\u01b0\u1eddng k\u00ednh<\/td>\n<td>Ti\u00eau chu\u1ea9n h\u00f3a theo \u0111\u01b0\u1eddng k\u00ednh<\/td>\n<td>Kh\u00f4ng ti\u00eau chu\u1ea9n \/ \u0111\u1eb7c bi\u1ec7t<\/td>\n<\/tr>\n<tr>\n<td>M\u1ee5c \u0111\u00edch ch\u00ednh<\/td>\n<td>\u1ed0c v\u00edt chung<\/td>\n<td>Ch\u1ed1ng rung, \u0111i\u1ec1u ch\u1ec9nh tinh<\/td>\n<td>B\u1ed9 ph\u1eadn th\u00e0nh m\u1ecfng, \u0111\u1ed9 ch\u00ednh x\u00e1c cao<\/td>\n<td>C\u0169, \u0111\u1eb7c bi\u1ec7t, kh\u00f4ng ti\u00eau chu\u1ea9n<\/td>\n<\/tr>\n<tr>\n<td>D\u1ea1ng ren<\/td>\n<td>60\u00b0 Th\u1ed1ng nh\u1ea5t<\/td>\n<td>60\u00b0 Th\u1ed1ng nh\u1ea5t<\/td>\n<td>60\u00b0 Th\u1ed1ng nh\u1ea5t<\/td>\n<td>60\u00b0 Th\u1ed1ng nh\u1ea5t<\/td>\n<\/tr>\n<tr>\n<td>\u0110\u01b0\u1ee3c qu\u1ea3n l\u00fd b\u1edfi<\/td>\n<td>ASME B1.1<\/td>\n<td>ASME B1.1<\/td>\n<td>ASME B1.1<\/td>\n<td>ASME B1.1<\/td>\n<\/tr>\n<tr>\n<td>V\u00ed d\u1ee5 k\u00fd hi\u1ec7u<\/td>\n<td>1\/4-20 UNC<\/td>\n<td>1\/4-28 UNF<\/td>\n<td>1\/4-32 UNEF<\/td>\n<td>1\/4-24 UNS<\/td>\n<\/tr>\n<tr>\n<td>Kh\u1ea3 n\u0103ng c\u00f3 s\u1eb5n<\/td>\n<td>R\u1ea5t r\u1ed9ng<\/td>\n<td>R\u1ed9ng<\/td>\n<td>Trung b\u00ecnh<\/td>\n<td>\u0110\u1eb7t h\u00e0ng \u0111\u1eb7c bi\u1ec7t \u0111i\u1ec3n h\u00ecnh<\/td>\n<\/tr>\n<tr>\n<td>D\u1ee5ng c\u1ee5<\/td>\n<td>B\u1ed9 tar\u00f4\/ren ti\u00eau chu\u1ea9n<\/td>\n<td>B\u1ed9 tar\u00f4\/ren ti\u00eau chu\u1ea9n<\/td>\n<td>B\u1ed9 tar\u00f4\/ren ti\u00eau chu\u1ea9n<\/td>\n<td>Th\u01b0\u1eddng l\u00e0 t\u00f9y ch\u1ec9nh ho\u1eb7c \u0111\u1eb7t h\u00e0ng \u0111\u1eb7c bi\u1ec7t<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<hr \/>\n<h2>Ti\u00eau chu\u1ea9n v\u00e0 Quy \u0111\u1ecbnh Ren UNS<\/h2>\n<p><strong>Ren UNS tu\u00e2n theo ASME B1.1, c\u00f9ng ti\u00eau chu\u1ea9n \u0111i\u1ec1u ch\u1ec9nh UNC, UNF v\u00e0 UNEF \u2014 bao g\u1ed3m h\u00ecnh d\u1ea1ng ren, c\u1ea5p dung sai v\u00e0 y\u00eau c\u1ea7u ki\u1ec3m tra gi\u1ed1ng h\u1ec7t nhau.<\/strong><\/p>\n<p>\u0110i\u1ec1u n\u00e0y quan tr\u1ecdng v\u00ec n\u00f3 c\u00f3 ngh\u0129a l\u00e0 ren UNS kh\u00f4ng ph\u1ea3i l\u00e0 lo\u1ea1i \u0111\u1eb7c bi\u1ec7t. Ch\u00fang l\u00e0 ren Th\u1ed1ng Nh\u1ea5t. B\u1ea1n s\u1eed d\u1ee5ng c\u00f9ng th\u01b0\u1edbc \u0111o ren, c\u00f9ng c\u00e1ch t\u00ednh dung sai v\u00e0 c\u00f9ng ph\u01b0\u01a1ng ph\u00e1p ki\u1ec3m tra. S\u1ef1 kh\u00e1c bi\u1ec7t duy nh\u1ea5t l\u00e0 b\u1ea3ng ren kh\u00f4ng li\u1ec7t k\u00ea b\u01b0\u1edbc ren \u201cti\u00eau chu\u1ea9n\u201d cho \u0111\u01b0\u1eddng k\u00ednh \u0111\u00f3 \u2014 b\u1ea1n l\u00e0m vi\u1ec7c d\u1ef1a tr\u00ean k\u00fd hi\u1ec7u th\u1ef1c t\u1ebf tr\u00ean b\u1ea3n v\u1ebd.<\/p>\n<h3>T\u1ed5ng quan v\u1ec1 Ti\u00eau chu\u1ea9n ASME B1.1<\/h3>\n<p>ASME B1.1 \u2014 <em>Ren v\u00edt h\u1ec7 inch Th\u1ed1ng Nh\u1ea5t (D\u1ea1ng ren UN v\u00e0 UNR)<\/em> \u2014 l\u00e0 t\u00e0i li\u1ec7u quy \u0111\u1ecbnh cho t\u1ea5t c\u1ea3 c\u00e1c d\u00f2ng ren Th\u1ed1ng Nh\u1ea5t t\u1ea1i Vi\u1ec7t Nam. \u0110\u01b0\u1ee3c xu\u1ea5t b\u1ea3n v\u00e0 duy tr\u00ec b\u1edfi <a href=\"https:\/\/www.asme.org\/\" target=\"_blank\" rel=\"noopener\">Hi\u1ec7p h\u1ed9i K\u1ef9 s\u01b0 C\u01a1 kh\u00ed Vi\u1ec7t Nam<\/a>, n\u00f3 quy \u0111\u1ecbnh:<\/p>\n<ul>\n<li>H\u00ecnh h\u1ecdc d\u1ea1ng ren (g\u00f3c, t\u1ef7 l\u1ec7 \u0111\u1ec9nh, ch\u00e2n ren)<\/li>\n<li>Dung sai cho t\u1eebng c\u1ea5p<\/li>\n<li>Y\u00eau c\u1ea7u ki\u1ec3m tra<\/li>\n<li>\u0110\u1ecbnh d\u1ea1ng k\u00fd hi\u1ec7u<\/li>\n<\/ul>\n<p>Ti\u00eau chu\u1ea9n n\u00e0y \u0111\u01b0\u1ee3c s\u1eeda \u0111\u1ed5i \u0111\u1ecbnh k\u1ef3; phi\u00ean b\u1ea3n hi\u1ec7n t\u1ea1i c\u0169ng bao g\u1ed3m bi\u1ebfn th\u1ec3 UNR (g\u1ed1c tr\u00f2n Th\u1ed1ng Nh\u1ea5t Qu\u1ed1c Gia) \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong ng\u00e0nh h\u00e0ng kh\u00f4ng v\u00e0 c\u00e1c \u1ee9ng d\u1ee5ng ch\u1ecbu m\u1ecfi cao. B\u1ea5t k\u1ef3 bu l\u00f4ng ho\u1eb7c l\u1ed7 tar\u00f4 n\u00e0o \u0111\u01b0\u1ee3c k\u00fd hi\u1ec7u l\u00e0 UNS \u0111\u1ec1u ph\u1ea3i tu\u00e2n th\u1ee7 ASME B1.1 v\u1ec1 d\u1ea1ng ren, m\u1eb7c d\u00f9 b\u01b0\u1edbc ren l\u00e0 \u201c\u0111\u1eb7c bi\u1ec7t\u201d.<\/p>\n<p>\u0110\u1ed1i v\u1edbi c\u00e1c lo\u1ea1i ren h\u1ec7 m\u00e9t t\u01b0\u01a1ng \u0111\u01b0\u01a1ng, ti\u00eau chu\u1ea9n t\u01b0\u01a1ng \u1ee9ng l\u00e0 ISO 68-1 v\u1ec1 d\u1ea1ng ren, trong khi Ch\u01b0\u01a1ng tr\u00ecnh H\u1ed7 tr\u1ee3 S\u1ea3n xu\u1ea5t c\u1ee7a NIST duy tr\u00ec c\u00e1c h\u01b0\u1edbng d\u1eabn tham kh\u1ea3o v\u1ec1 th\u1ef1c h\u00e0nh \u0111o ren t\u1ed1t nh\u1ea5t t\u1ea1i c\u00e1c x\u01b0\u1edfng \u1edf Vi\u1ec7t Nam.<\/p>\n<h3>C\u00e1c c\u1ea5p dung sai ren cho ren UNS<\/h3>\n<p>ASME B1.1 \u0111\u1ecbnh ngh\u0129a ba c\u1ea5p \u0111\u1ed9 l\u1eafp gh\u00e9p cho c\u1ea3 ren ngo\u00e0i v\u00e0 ren trong:<\/p>\n<p><strong>Ren ngo\u00e0i (bu l\u00f4ng, v\u00edt):<\/strong><br \/>\n&#8211; <strong>C\u1ea5p 1A<\/strong> \u2014 l\u1eafp l\u1ecfng, khe h\u1edf t\u1ed1i \u0111a, d\u1ec5 l\u1eafp r\u00e1p ngay c\u1ea3 khi c\u00f3 b\u1ee5i b\u1ea9n ho\u1eb7c h\u01b0 h\u1ea1i<br \/>\n&#8211; <strong>C\u1ea5p 2A<\/strong> \u2014 l\u1eafp gh\u00e9p ti\u00eau chu\u1ea9n \u0111a d\u1ee5ng; m\u1eb7c \u0111\u1ecbnh cho h\u1ea7u h\u1ebft c\u00e1c ch\u1ed1t th\u01b0\u01a1ng m\u1ea1i<br \/>\n&#8211; <strong>C\u1ea5p 3A<\/strong> \u2014 l\u1eafp ch\u1eb7t, khe h\u1edf t\u1ed1i thi\u1ec3u; d\u00f9ng cho c\u00e1c \u1ee9ng d\u1ee5ng y\u00eau c\u1ea7u \u0111\u1ed9 ch\u00ednh x\u00e1c ho\u1eb7c an to\u00e0n cao<\/p>\n<p><strong>Ren trong (\u0111ai \u1ed1c, l\u1ed7 ren):<\/strong><br \/>\n&#8211; <strong>C\u1ea5p 1B<\/strong> \u2014 l\u1eafp v\u1edbi 1A; dung sai r\u1ed9ng, l\u1eafp l\u1ecfng<br \/>\n&#8211; <strong>C\u1ea5p 2B<\/strong> \u2014 ti\u00eau chu\u1ea9n \u0111a d\u1ee5ng; l\u1eafp v\u1edbi 2A<br \/>\n&#8211; <strong>C\u1ea5p 3B<\/strong> \u2014 l\u1eafp ch\u00ednh x\u00e1c; l\u1eafp v\u1edbi 3A<\/p>\n<p>\u0110\u1ed1i v\u1edbi ren UNS, k\u00fd hi\u1ec7u c\u1ea5p xu\u1ea5t hi\u1ec7n trong ch\u1ec9 d\u1eabn ren, gi\u1ed1ng nh\u01b0 \u0111\u1ed1i v\u1edbi UNC v\u00e0 UNF. H\u1ea7u h\u1ebft c\u00e1c \u1ee9ng d\u1ee5ng ren UNS s\u1eed d\u1ee5ng <strong>2A\/2B<\/strong> (gi\u1ed1ng m\u1eb7c \u0111\u1ecbnh nh\u01b0 c\u00e1c ch\u1ed1t th\u01b0\u01a1ng m\u1ea1i th\u00f4ng th\u01b0\u1eddng), tr\u1eeb khi \u1ee9ng d\u1ee5ng y\u00eau c\u1ea7u l\u1eafp ch\u00ednh x\u00e1c (3A\/3B) ho\u1eb7c l\u1eafp l\u1ecfng d\u1ec5 b\u1ea3o tr\u00ec (1A\/1B).<\/p>\n<p>Trong th\u1ef1c t\u1ebf, ch\u00fang t\u00f4i nh\u1eadn th\u1ea5y ph\u1ea7n l\u1edbn c\u00e1c ch\u1ec9 d\u1eabn ren UNS xu\u1ea5t hi\u1ec7n tr\u00ean b\u1ea3n v\u1ebd x\u01b0\u1edfng \u0111\u1ec1u ch\u1ec9 \u0111\u1ecbnh 2A ho\u1eb7c 2B. C\u1ea5p 3 ch\u1ee7 y\u1ebfu xu\u1ea5t hi\u1ec7n trong c\u00e1c b\u1ed9 b\u1ea3n v\u1ebd ng\u00e0nh h\u00e0ng kh\u00f4ng, n\u01a1i k\u00fd hi\u1ec7u UNS th\u01b0\u1eddng \u0111i k\u00e8m v\u1edbi dung sai ch\u1eb7t v\u1ec1 \u0111\u01b0\u1eddng k\u00ednh v\u00e0 \u0111\u1ed9 nh\u1eb5n b\u1ec1 m\u1eb7t.<\/p>\n<h3>C\u00e1ch \u0111\u1ecdc ch\u1ec9 d\u1eabn ren UNS<\/h3>\n<p>M\u1ed9t k\u00fd hi\u1ec7u ren UNS \u0111\u1ea7y \u0111\u1ee7 tu\u00e2n theo c\u1ea5u tr\u00fac sau:<\/p>\n<pre><code>[\u0110\u01b0\u1eddng k\u00ednh danh ngh\u0129a]-[S\u1ed1 ren tr\u00ean inch] UNS-[C\u1ea5p \u0111\u1ed9]\n<\/code><\/pre>\n<p><strong>V\u00ed d\u1ee5:<\/strong> <code>1-14 UNS-2A<\/code><\/p>\n<p>Ph\u00e2n t\u00edch:<\/p>\n<table>\n<thead>\n<tr>\n<th>Nguy\u00ean t\u1ed1<\/th>\n<th>Gi\u00e1 tr\u1ecb<\/th>\n<th>\u00dd ngh\u0129a<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>\u0110\u01b0\u1eddng k\u00ednh danh ngh\u0129a<\/td>\n<td>1<\/td>\n<td>\u0110\u01b0\u1eddng k\u00ednh danh ngh\u0129a 1 inch<\/td>\n<\/tr>\n<tr>\n<td>TPI<\/td>\n<td>14<\/td>\n<td>14 ren tr\u00ean m\u1ed7i inch<\/td>\n<\/tr>\n<tr>\n<td>D\u00f2ng<\/td>\n<td>UNS<\/td>\n<td>Ren \u0111\u1eb7c bi\u1ec7t qu\u1ed1c gia th\u1ed1ng nh\u1ea5t<\/td>\n<\/tr>\n<tr>\n<td>L\u1edbp<\/td>\n<td>2A<\/td>\n<td>Ren ngo\u00e0i, \u0111\u1ed9 kh\u00edt th\u01b0\u01a1ng m\u1ea1i ti\u00eau chu\u1ea9n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>So s\u00e1nh: <code>1-8 UNC-2A<\/code> (1 inch, 8 ren\/inch, lo\u1ea1i th\u00f4 ti\u00eau chu\u1ea9n) v\u00e0 <code>1-12 UNF-2A<\/code> (1 inch, 12 ren\/inch, lo\u1ea1i m\u1ecbn). \u1ede \u0111\u01b0\u1eddng k\u00ednh 1 inch, 14 ren\/inch kh\u00f4ng ph\u1ea3i l\u00e0 UNC (8 ren\/inch) c\u0169ng kh\u00f4ng ph\u1ea3i UNF (12 ren\/inch), v\u00ec v\u1eady \u0111\u01b0\u1ee3c k\u00fd hi\u1ec7u \u0111\u00fang l\u00e0 UNS.<\/p>\n<p>Cho <strong>ren trong<\/strong>, h\u1eadu t\u1ed1 c\u1ea5p \u0111\u1ed9 thay \u0111\u1ed5i: <code>1-14 UNS-2B<\/code> cho l\u1ed7 \u0111\u00e3 taro.<\/p>\n<p>Ren ph\u1ea3i \u0111\u01b0\u1ee3c hi\u1ec3u m\u1eb7c \u0111\u1ecbnh tr\u1eeb khi c\u00f3 ghi LH (tr\u00e1i): <code>1-14 UNS-2A-LH<\/code>.<\/p>\n<p><img decoding=\"async\" alt=\"Ren UNS \u2014 minh h\u1ecda c\u00e1c lo\u1ea1i, so s\u00e1nh m\u1eb7t c\u1eaft ngang c\u1ee7a c\u00e1c bi\u00ean d\u1ea1ng ren UNC, UNF v\u00e0 UNS \u0111\u1eb7t c\u1ea1nh nhau\" src=\"https:\/\/productionscrews.com\/wp-content\/uploads\/2026\/05\/uns-thread-types.png\" \/><\/p>\n<hr \/>\n<h2>B\u1ea3ng k\u00edch th\u01b0\u1edbc ren UNS (Tham kh\u1ea3o \u0111\u1ea7y \u0111\u1ee7)<\/h2>\n<p><strong>Ren UNS kh\u00f4ng c\u00f3 b\u1ea3ng k\u00edch th\u01b0\u1edbc c\u1ed1 \u0111\u1ecbnh \u2014 k\u00fd hi\u1ec7u n\u00e0y \u00e1p d\u1ee5ng cho b\u1ea5t k\u1ef3 ren d\u1ea1ng Unified n\u00e0o kh\u00f4ng thu\u1ed9c UNC\/UNF\/UNEF \u2014 nh\u01b0ng c\u00e1c k\u00edch th\u01b0\u1edbc UNS ph\u1ed5 bi\u1ebfn th\u01b0\u1eddng xu\u1ea5t hi\u1ec7n trong ng\u00e0nh c\u00f4ng nghi\u1ec7p v\u00e0 thi\u1ebft b\u1ecb c\u0169.<\/strong><\/p>\n<p>D\u01b0\u1edbi \u0111\u00e2y l\u00e0 b\u1ea3ng tham kh\u1ea3o v\u1ec1 c\u00e1c k\u00edch th\u01b0\u1edbc ren UNS th\u01b0\u1eddng g\u1eb7p nh\u1ea5t. \u0110\u00e2y l\u00e0 c\u00e1c b\u01b0\u1edbc ren m\u00e0 c\u00e1c k\u1ef9 s\u01b0 \u0111\u00e3 ch\u1ecdn khi c\u00e1c b\u01b0\u1edbc ren ti\u00eau chu\u1ea9n kh\u00f4ng ph\u00f9 h\u1ee3p v\u1edbi \u1ee9ng d\u1ee5ng. Lu\u00f4n ki\u1ec3m tra l\u1ea1i v\u1edbi b\u1ea3n v\u1ebd th\u1ef1c t\u1ebf c\u1ee7a b\u1ea1n \u2014 \u0111\u1eebng cho r\u1eb1ng b\u1ea5t k\u1ef3 t\u1ed5 h\u1ee3p UNS n\u00e0o trong b\u1ea3ng n\u00e0y c\u00f3 th\u1ec3 thay th\u1ebf cho ren ti\u00eau chu\u1ea9n c\u00f3 h\u00ecnh d\u1ea1ng t\u01b0\u01a1ng t\u1ef1.<\/p>\n<p><strong>B\u1ea2NG 2 \u2014 K\u00edch th\u01b0\u1edbc ren UNS ph\u1ed5 bi\u1ebfn (Th\u01b0\u1eddng d\u00f9ng trong ng\u00e0nh c\u00f4ng nghi\u1ec7p)<\/strong><\/p>\n<table>\n<thead>\n<tr>\n<th>\u0110\u01b0\u1eddng k\u00ednh danh ngh\u0129a<\/th>\n<th>S\u1ed1 v\u00f2ng ren tr\u00ean inch (UNS)<\/th>\n<th>T\u1ea1i sao d\u00f9ng UNS (kh\u00f4ng d\u00f9ng UNC\/UNF\/UNEF)<\/th>\n<th>Khu v\u1ef1c \u1ee9ng d\u1ee5ng ph\u1ed5 bi\u1ebfn<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>S\u1ed1 10 (0.190\u2033)<\/td>\n<td>32<\/td>\n<td>UNC=24, UNF=32 \u2192 32 v\u00f2ng ren tr\u00ean #10 th\u1ef1c ra l\u00e0 UNF; UNS s\u1ebd l\u00e0 lo\u1ea1i kh\u00f4ng ti\u00eau chu\u1ea9n nh\u01b0 28<\/td>\n<td>T\u1ea5m v\u00e1ch m\u1ecfng<\/td>\n<\/tr>\n<tr>\n<td>1\/4&#8243;<\/td>\n<td>24<\/td>\n<td>UNC=20, UNF=28<\/td>\n<td>Kh\u1edbp n\u1ed1i th\u1ee7y l\u1ef1c<\/td>\n<\/tr>\n<tr>\n<td>5\/16&#8243;<\/td>\n<td>24<\/td>\n<td>UNC=18, UNF=24 \u2192 24 v\u00f2ng ren t\u1ea1i 5\/16 l\u00e0 UNF<\/td>\n<td>\u1ed0c v\u00edt d\u1ee5ng c\u1ee5<\/td>\n<\/tr>\n<tr>\n<td>3\/8&#8243;<\/td>\n<td>24<\/td>\n<td>UNC=16, UNF=24 \u2192 24 v\u00f2ng ren t\u1ea1i 3\/8 l\u00e0 UNF; UNS s\u1ebd l\u00e0 v\u00ed d\u1ee5 nh\u01b0 20<\/td>\n<td>Ph\u1ee5 ki\u1ec7n c\u1ea3i ti\u1ebfn<\/td>\n<\/tr>\n<tr>\n<td>1\/2&#8243;<\/td>\n<td>20<\/td>\n<td>UNC=13, UNF=20 \u2192 20 v\u00f2ng ren t\u1ea1i 1\/2 l\u00e0 UNF; UNS t\u1ea1i \u0111\u01b0\u1eddng k\u00ednh n\u00e0y c\u00f3 th\u1ec3 l\u00e0 18<\/td>\n<td>\u0110\u1ea7u n\u1ed1i chuy\u00ean d\u1ee5ng<\/td>\n<\/tr>\n<tr>\n<td>5\/8&#8243;<\/td>\n<td>18<\/td>\n<td>UNC=11, UNF=18 \u2192 18 v\u00f2ng ren t\u1ea1i 5\/8 l\u00e0 UNF; UNS c\u00f3 th\u1ec3 l\u00e0 14<\/td>\n<td>Kh\u1edbp n\u1ed1i ng\u00e0nh d\u1ea7u kh\u00ed<\/td>\n<\/tr>\n<tr>\n<td>3\/4&#8243;<\/td>\n<td>16<\/td>\n<td>UNC=10, UNF=16 \u2192 16 v\u00f2ng ren t\u1ea1i 3\/4 l\u00e0 UNF; UNS c\u00f3 th\u1ec3 l\u00e0 12<\/td>\n<td>V\u1ecf b\u01a1m<\/td>\n<\/tr>\n<tr>\n<td>1&#8243;<\/td>\n<td>14<\/td>\n<td>UNC=8, UNF=12 \u2192 14 TPI t\u1ea1i 1\u2033 l\u00e0 UNS<\/td>\n<td>Xi lanh th\u1ee7y l\u1ef1c<\/td>\n<\/tr>\n<tr>\n<td>1-1\/4&#8243;<\/td>\n<td>12<\/td>\n<td>UNC=7, UNF=12 \u2192 12 TPI t\u1ea1i 1-1\/4 = UNF; UNS c\u00f3 th\u1ec3 l\u00e0 10<\/td>\n<td>Thi\u1ebft b\u1ecb h\u1ea1ng n\u1eb7ng<\/td>\n<\/tr>\n<tr>\n<td>1-1\/2&#8243;<\/td>\n<td>12<\/td>\n<td>UNC=6, UNF=12 \u2192 12 TPI t\u1ea1i 1-1\/2 = UNF; UNS c\u00f3 th\u1ec3 l\u00e0 10<\/td>\n<td>M\u1eb7t b\u00edch<\/td>\n<\/tr>\n<tr>\n<td>2&#8243;<\/td>\n<td>12<\/td>\n<td>UNC=4.5, UNF=12 \u2192 12 TPI t\u1ea1i 2\u2033 c\u00f3 kh\u1ea3 n\u0103ng l\u00e0 UNS ho\u1eb7c UNEF<\/td>\n<td>B\u00ecnh ch\u1ecbu \u00e1p l\u1ef1c<\/td>\n<\/tr>\n<tr>\n<td>2-1\/2&#8243;<\/td>\n<td>12<\/td>\n<td>UNC=4, UNF=\u2014; 12 TPI l\u00e0 UNS<\/td>\n<td>M\u1eb7t b\u00edch l\u1edbn, ph\u1ee5 ki\u1ec7n \u1ed1ng<\/td>\n<\/tr>\n<tr>\n<td>3&#8243;<\/td>\n<td>12<\/td>\n<td>UNC=4; 12 TPI l\u00e0 UNS<\/td>\n<td>M\u1eb7t b\u00edch h\u1ea1ng n\u1eb7ng<\/td>\n<\/tr>\n<tr>\n<td>4&#8243;<\/td>\n<td>12<\/td>\n<td>UNC=4; 12 TPI l\u00e0 UNS<\/td>\n<td>Ph\u1ee5 ki\u1ec7n \u1ed1ng r\u1ea5t l\u1edbn<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<blockquote>\n<p><strong>Quan tr\u1ecdng:<\/strong> M\u1ed9t s\u1ed1 k\u1ebft h\u1ee3p trong b\u1ea3ng n\u00e0y c\u00f3 th\u1ec3 tr\u00f9ng v\u1edbi UNF ho\u1eb7c UNEF \u1edf m\u1ed9t s\u1ed1 \u0111\u01b0\u1eddng k\u00ednh nh\u1ea5t \u0111\u1ecbnh. Lu\u00f4n ki\u1ec3m tra b\u1ea3ng ASME B1.1 \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh ch\u00ednh x\u00e1c \u0111\u01b0\u1eddng k\u00ednh c\u1ea7n thi\u1ebft. N\u1ebfu b\u01b0\u1edbc ren tr\u00f9ng v\u1edbi m\u1ed9t d\u00f2ng ti\u00eau chu\u1ea9n, h\u00e3y s\u1eed d\u1ee5ng k\u00fd hi\u1ec7u d\u00f2ng \u0111\u00f3 \u2014 \u0111\u1eebng g\u1ecdi l\u00e0 UNS.<\/p>\n<\/blockquote>\n<p>C\u00e1c lo\u1ea1i ren UNS \u201cchu\u1ea9n\u201d th\u01b0\u1eddng g\u1eb7p nh\u1ea5t trong s\u1ea3n xu\u1ea5t th\u1ef1c t\u1ebf l\u00e0 1-14 UNS (xi lanh th\u1ee7y l\u1ef1c), 2-12 UNS (m\u1eb7t b\u00edch b\u00ecnh ch\u1ecbu \u00e1p l\u1ef1c), v\u00e0 c\u00e1c \u0111\u01b0\u1eddng k\u00ednh \u0111\u1eb7c bi\u1ec7t trong kho\u1ea3ng 1.5\u2033\u20134\u2033 m\u00e0 kh\u00f4ng c\u00f3 d\u00f2ng b\u01b0\u1edbc ren ti\u00eau chu\u1ea9n n\u00e0o ph\u00f9 h\u1ee3p v\u1edbi 12 TPI.<\/p>\n<h3>\u0110\u1eb7t h\u00e0ng b\u1ed9 taro v\u00e0 b\u00e0n ren UNS<\/h3>\n<p>B\u1ed9 taro v\u00e0 b\u00e0n ren ti\u00eau chu\u1ea9n kh\u00f4ng bao g\u1ed3m k\u00edch th\u01b0\u1edbc UNS. Khi c\u1ea7n c\u1eaft ren UNS, b\u1ea1n c\u00f3 hai l\u1ef1a ch\u1ecdn:<\/p>\n<ol>\n<li><strong>\u0110\u1eb7t h\u00e0ng taro\/b\u00e0n ren \u0111\u1eb7c bi\u1ec7t<\/strong> \u2014 c\u00e1c nh\u00e0 cung c\u1ea5p d\u1ee5ng c\u1ee5 l\u1edbn (Greenfield, OSG, Emuge, Balax) s\u1ea3n xu\u1ea5t taro UNS theo \u0111\u01a1n \u0111\u1eb7t h\u00e0ng, th\u01b0\u1eddng c\u00f3 th\u1eddi gian giao h\u00e0ng 2\u20134 tu\u1ea7n v\u00e0 gi\u00e1 cao h\u01a1n so v\u1edbi s\u1ea3n ph\u1ea9m trong danh m\u1ee5c<\/li>\n<li><strong>Gia c\u00f4ng ren b\u1eb1ng m\u00e1y phay<\/strong> \u2014 tr\u00ean m\u1ed9t trung t\u00e2m gia c\u00f4ng CNC, dao phay ren c\u00f3 th\u1ec3 c\u1eaft b\u1ea5t k\u1ef3 lo\u1ea1i ren d\u1ea1ng Unified n\u00e0o b\u1ea5t k\u1ec3 b\u01b0\u1edbc ren; b\u1ea1n ch\u1ec9 c\u1ea7n l\u1eadp tr\u00ecnh s\u1ed1 TPI mong mu\u1ed1n<\/li>\n<\/ol>\n<p>\u0110\u1ed1i v\u1edbi s\u1ea3n xu\u1ea5t s\u1ed1 l\u01b0\u1ee3ng l\u1edbn c\u00e1c chi ti\u1ebft ren UNS, phay ren ho\u1eb7c d\u1ee5ng c\u1ee5 t\u00f9y ch\u1ec9nh s\u1ebd nhanh ch\u00f3ng mang l\u1ea1i hi\u1ec7u qu\u1ea3. \u0110\u1ed1i v\u1edbi c\u00f4ng vi\u1ec7c s\u1eeda ch\u1eefa ho\u1eb7c n\u00e2ng c\u1ea5p t\u1eebng chi\u1ebfc, phay ren g\u1ea7n nh\u01b0 lu\u00f4n l\u00e0 l\u1ef1a ch\u1ecdn th\u1ef1c t\u1ebf h\u01a1n.<\/p>\n<hr \/>\n<h2>\u1ee8ng d\u1ee5ng ren UNS v\u00e0 c\u00e1c tr\u01b0\u1eddng h\u1ee3p s\u1eed d\u1ee5ng trong ng\u00e0nh<\/h2>\n<p><strong>Ren UNS xu\u1ea5t hi\u1ec7n ph\u1ed5 bi\u1ebfn nh\u1ea5t trong ng\u00e0nh h\u00e0ng kh\u00f4ng v\u0169 tr\u1ee5, d\u1ea7u kh\u00ed, th\u1ee7y l\u1ef1c v\u00e0 thi\u1ebft b\u1ecb c\u00f4ng nghi\u1ec7p c\u0169 n\u01a1i c\u00e1c k\u1ebft h\u1ee3p b\u01b0\u1edbc ren ti\u00eau chu\u1ea9n kh\u00f4ng \u0111\u00e1p \u1ee9ng \u0111\u01b0\u1ee3c y\u00eau c\u1ea7u v\u1ec1 \u0111\u1ed9 b\u1ec1n, \u0111\u1ed9 d\u00e0y th\u00e0nh ho\u1eb7c t\u00ednh li\u00ean t\u1ee5c thi\u1ebft k\u1ebf c\u1ee5 th\u1ec3.<\/strong><\/p>\n<h3>H\u00e0ng kh\u00f4ng v\u0169 tr\u1ee5 v\u00e0 Qu\u1ed1c ph\u00f2ng<\/h3>\n<p>H\u00e0ng kh\u00f4ng v\u0169 tr\u1ee5 c\u00f3 l\u1ebd l\u00e0 ng\u00e0nh s\u1eed d\u1ee5ng ren UNS nhi\u1ec1u nh\u1ea5t. C\u00e1c thi\u1ebft k\u1ebf m\u00e1y bay b\u1eaft ngu\u1ed3n t\u1eeb nh\u1eefng n\u0103m 1940\u20131970 th\u01b0\u1eddng y\u00eau c\u1ea7u ren UNS c\u00f3 tr\u01b0\u1edbc c\u00e1c d\u00f2ng ti\u00eau chu\u1ea9n hi\u1ec7n t\u1ea1i ho\u1eb7c ph\u1ea3n \u00e1nh y\u00eau c\u1ea7u th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt qu\u00e2n s\u1ef1 c\u1ee7a th\u1eddi k\u1ef3 \u0111\u00f3. <a href=\"https:\/\/www.faa.gov\/regulations_policies\/advisory_circulars\/\" target=\"_blank\" rel=\"noopener\">C\u00e1c th\u00f4ng t\u01b0 h\u01b0\u1edbng d\u1eabn c\u1ee7a C\u1ee5c H\u00e0ng kh\u00f4ng Vi\u1ec7t Nam v\u1ec1 ph\u1ea7n c\u1ee9ng m\u00e1y bay<\/a> nh\u1ea5n m\u1ea1nh t\u1ea7m quan tr\u1ecdng c\u1ee7a vi\u1ec7c x\u00e1c \u0111\u1ecbnh ch\u00ednh x\u00e1c th\u00f4ng s\u1ed1 ren khi thay th\u1ebf ch\u1ed1t trong m\u00e1y bay \u0111\u01b0\u1ee3c ch\u1ee9ng nh\u1eadn.<\/p>\n<p>Trong th\u1ef1c t\u1ebf, ch\u00fang t\u00f4i \u0111\u00e3 th\u1ea5y c\u00e1c y\u00eau c\u1ea7u ren UNS tr\u00ean:<\/p>\n<ul>\n<li>Bu l\u00f4ng g\u1eafn \u0111\u1ed9ng c\u01a1 n\u01a1i \u0111\u1ed9 d\u00e0y th\u00e0nh h\u1ea1n ch\u1ebf kh\u00f4ng cho ph\u00e9p d\u00f9ng UNF nh\u01b0ng ren UNC th\u00f4 l\u1ea1i kh\u00f4ng cung c\u1ea5p \u0111\u1ee7 l\u1ef1c k\u1eb9p<\/li>\n<li>Thanh truy\u1ec1n \u0111\u1ed9ng th\u1ee7y l\u1ef1c n\u01a1i 1-14 UNS cung c\u1ea5p b\u01b0\u1edbc ren trung gian gi\u1eefa UNC v\u00e0 UNF cho c\u1ea3 \u0111\u1ed9 b\u1ec1n v\u00e0 kh\u1ea3 n\u0103ng l\u00e0m k\u00edn<\/li>\n<li>Ch\u1ed1t gi\u00e1 \u0111\u1ee1 thi\u1ebft b\u1ecb \u0111i\u1ec7n t\u1eed trong c\u00e1c h\u1ec7 th\u1ed1ng c\u0169 v\u1eabn \u0111ang \u0111\u01b0\u1ee3c b\u1ea3o tr\u00ec<\/li>\n<\/ul>\n<p>Khi m\u1ed9t b\u1ea3n v\u1ebd qu\u00e2n s\u1ef1 y\u00eau c\u1ea7u ren UNS, th\u00f4ng s\u1ed1 \u0111\u00f3 \u0111\u01b0\u1ee3c c\u1ed1 \u0111\u1ecbnh b\u1edfi phi\u00ean b\u1ea3n b\u1ea3n v\u1ebd. Thay th\u1ebf b\u1eb1ng UNC ho\u1eb7c UNF \u2014 ngay c\u1ea3 khi b\u01b0\u1edbc ren \u201cg\u1ea7n gi\u1ed1ng\u201d \u2014 kh\u00f4ng \u0111\u01b0\u1ee3c ph\u00e9p n\u1ebfu kh\u00f4ng c\u00f3 l\u1ec7nh thay \u0111\u1ed5i k\u1ef9 thu\u1eadt.<\/p>\n<h3>Thi\u1ebft b\u1ecb D\u1ea7u kh\u00ed<\/h3>\n<p>Ren UNS \u0111\u01b0\u1eddng k\u00ednh l\u1edbn ph\u1ed5 bi\u1ebfn r\u1ed9ng r\u00e3i trong thi\u1ebft b\u1ecb d\u1ea7u kh\u00ed: van ch\u1ed1ng phun, \u0111\u1ea7u gi\u1ebfng, th\u00e2n van v\u00e0 k\u1ebft n\u1ed1i \u1ed1ng v\u1edbi m\u1eb7t b\u00edch. \u1ede \u0111\u01b0\u1eddng k\u00ednh 2\u2033, 3\u2033 v\u00e0 4\u2033, c\u1ea3 UNC l\u1eabn UNF \u0111\u1ec1u kh\u00f4ng cung c\u1ea5p b\u01b0\u1edbc ren 12 TPI \u2014 nh\u01b0ng 12 TPI \u1edf c\u00e1c \u0111\u01b0\u1eddng k\u00ednh \u0111\u00f3 l\u1ea1i cho chi\u1ec1u d\u00e0i \u0103n kh\u1edbp v\u00e0 hi\u1ec7u su\u1ea5t l\u00e0m k\u00edn tuy\u1ec7t v\u1eddi d\u01b0\u1edbi \u00e1p su\u1ea5t cao.<\/p>\n<p>\u0110\u1ea7u thanh v\u00e0 n\u1eafp xi lanh th\u1ee7y l\u1ef1c c\u0169ng th\u01b0\u1eddng s\u1eed d\u1ee5ng ren UNS. M\u1ed9t thanh th\u1ee7y l\u1ef1c 2.5 inch ren 12 TPI UNS cung c\u1ea5p \u0111\u1ed9 b\u1ec1n \u0103n kh\u1edbp ren l\u1edbn h\u01a1n nhi\u1ec1u so v\u1edbi 4 TPI UNC \u1edf c\u00f9ng \u0111\u01b0\u1eddng k\u00ednh, \u0111\u1ed3ng th\u1eddi y\u00eau c\u1ea7u lo\u1ea1i b\u1ecf v\u1eadt li\u1ec7u \u00edt h\u01a1n so v\u1edbi b\u01b0\u1edbc ren UNEF. Theo d\u1eef li\u1ec7u ng\u00e0nh do <a href=\"https:\/\/www.ifps.org\/\" target=\"_blank\" rel=\"noopener\">Hi\u1ec7p h\u1ed9i C\u00f4ng ngh\u1ec7 Th\u1ee7y l\u1ef1c<\/a>t\u1ed5ng h\u1ee3p, c\u00e1c l\u1ed7i xi lanh th\u1ee7y l\u1ef1c t\u1ea1i k\u1ebft n\u1ed1i ren th\u01b0\u1eddng b\u1eaft ngu\u1ed3n t\u1eeb l\u1eafp r\u00e1p sai b\u01b0\u1edbc ren \u2014 khi\u1ebfn vi\u1ec7c x\u00e1c \u0111\u1ecbnh \u0111\u00fang ren UNS tr\u1edf n\u00ean quan tr\u1ecdng.<\/p>\n<h3>Thi\u1ebft b\u1ecb Y t\u1ebf v\u00e0 Khoa h\u1ecdc<\/h3>\n<p>D\u1ee5ng c\u1ee5 ph\u1eabu thu\u1eadt v\u00e0 thi\u1ebft b\u1ecb khoa h\u1ecdc ch\u00ednh x\u00e1c th\u01b0\u1eddng s\u1eed d\u1ee5ng ren UNS cho c\u01a1 c\u1ea5u \u0111i\u1ec1u ch\u1ec9nh n\u01a1i b\u01b0\u1edbc ren ph\u1ea3i \u0111\u01b0\u1ee3c ch\u1ecdn ch\u00ednh x\u00e1c cho t\u1ed1c \u0111\u1ed9 ti\u1ebfn m\u1ed7i v\u00f2ng quay. M\u1ed9t v\u00edt \u0111i\u1ec1u ch\u1ec9nh 0.5 inch v\u1edbi 40 TPI UNS ti\u1ebfn \u0111\u00fang 0.025 inch m\u1ed7i v\u00f2ng \u2014 m\u1ed9t m\u1ee9c ti\u1ec7n l\u1ee3i cho \u1ee9ng d\u1ee5ng \u0111o vi m\u00f4 n\u01a1i kh\u00f4ng c\u00f3 d\u00f2ng ti\u00eau chu\u1ea9n n\u00e0o cung c\u1ea5p b\u01b0\u1edbc ren \u0111\u00f3.<\/p>\n<p>Thi\u1ebft b\u1ecb ph\u00f2ng th\u00ed nghi\u1ec7m, gi\u00e1 \u0111\u1ee1 quang h\u1ecdc v\u00e0 m\u1ed9t s\u1ed1 v\u1ecf thi\u1ebft b\u1ecb c\u1ea5y gh\u00e9p c\u0169ng s\u1eed d\u1ee5ng ren UNS v\u00ec l\u00fd do t\u01b0\u01a1ng t\u1ef1: b\u01b0\u1edbc ren \u0111\u01b0\u1ee3c ch\u1ecdn cho ch\u1ee9c n\u0103ng (t\u1ed1c \u0111\u1ed9 ti\u1ebfn, \u0111\u1ed9 b\u1ec1n \u0103n kh\u1edbp ho\u1eb7c tr\u00e1nh t\u1ea7n s\u1ed1 rung), kh\u00f4ng ph\u1ea3i \u0111\u1ec3 tu\u00e2n th\u1ee7 d\u00f2ng b\u01b0\u1edbc ren ti\u00eau chu\u1ea9n.<\/p>\n<hr \/>\n<h2>C\u00e1ch ch\u1ecdn ren UNS ph\u00f9 h\u1ee3p<\/h2>\n<p><strong>S\u1eed d\u1ee5ng UNS khi kh\u00f4ng c\u00f3 b\u01b0\u1edbc ren ti\u00eau chu\u1ea9n n\u00e0o \u0111\u00e1p \u1ee9ng \u0111\u1ed3ng th\u1eddi c\u00e1c y\u00eau c\u1ea7u v\u1ec1 \u0111\u1ed9 b\u1ec1n ren, \u0111\u1ed9 d\u00e0y th\u00e0nh, chi\u1ec1u d\u00e0i \u0103n kh\u1edbp v\u00e0 kh\u1ea3 n\u0103ng t\u01b0\u01a1ng th\u00edch v\u1edbi m\u1ed9t chi ti\u1ebft hi\u1ec7n c\u00f3.<\/strong><\/p>\n<p><img decoding=\"async\" alt=\"Ren UNS \u2014 s\u01a1 \u0111\u1ed3 quy\u1ebft \u0111\u1ecbnh h\u01b0\u1edbng d\u1eabn quy tr\u00ecnh l\u1ef1a ch\u1ecdn gi\u1eefa UNC, UNF, UNEF v\u00e0 UNS\" src=\"https:\/\/productionscrews.com\/wp-content\/uploads\/2026\/05\/uns-thread-howto.png\" \/><\/p>\n<h3>Khi n\u00e0o n\u00ean s\u1eed d\u1ee5ng UNS thay v\u00ec UNC ho\u1eb7c UNF<\/h3>\n<p>S\u01a1 \u0111\u1ed3 quy\u1ebft \u0111\u1ecbnh r\u1ea5t \u0111\u01a1n gi\u1ea3n:<\/p>\n<ol>\n<li>\n<p><strong>UNC c\u00f3 \u0111\u00e1p \u1ee9ng y\u00eau c\u1ea7u v\u1ec1 \u0111\u1ed9 b\u1ec1n c\u1ee7a b\u1ea1n kh\u00f4ng?<\/strong> N\u1ebfu c\u00f3, h\u00e3y s\u1eed d\u1ee5ng UNC. Ren th\u00f4 d\u1ec5 l\u1eafp r\u00e1p h\u01a1n, ch\u1ed1ng ch\u00e9o ren t\u1ed1t h\u01a1n v\u00e0 d\u1ee5ng c\u1ee5 lu\u00f4n s\u1eb5n c\u00f3.<\/p>\n<\/li>\n<li>\n<p><strong>UNF c\u00f3 cung c\u1ea5p \u0111\u1ee7 \u0111\u1ed9 \u0103n kh\u1edbp ren m\u00e0 kh\u00f4ng lo m\u1ecfng th\u00e0nh kh\u00f4ng?<\/strong> N\u1ebfu c\u00f3, h\u00e3y s\u1eed d\u1ee5ng UNF. Ren m\u1ecbn cho \u0111\u1ed9 b\u1ec1n k\u00e9o cao h\u01a1n tr\u00ean m\u1ed7i \u0111\u01b0\u1eddng k\u00ednh bu l\u00f4ng v\u00e0 kh\u1ea3 n\u0103ng t\u1ef1 kh\u00f3a t\u1ed1t h\u01a1n khi rung \u0111\u1ed9ng.<\/p>\n<\/li>\n<li>\n<p><strong>C\u00f3 b\u01b0\u1edbc ren ti\u00eau chu\u1ea9n n\u00e0o cho \u0111\u01b0\u1eddng k\u00ednh c\u1ee5 th\u1ec3 c\u1ee7a b\u1ea1n kh\u00f4ng?<\/strong> Ki\u1ec3m tra c\u00e1c b\u1ea3ng ASME B1.1. N\u1ebfu b\u01b0\u1edbc ren b\u1ea1n c\u1ea7n kh\u00f4ng c\u00f3 trong UNC, UNF ho\u1eb7c UNEF \u1edf \u0111\u01b0\u1eddng k\u00ednh c\u1ee7a b\u1ea1n, th\u00ec UNS l\u00e0 l\u1ef1a ch\u1ecdn \u0111\u00fang.<\/p>\n<\/li>\n<li>\n<p><strong>\u0110\u00e2y c\u00f3 ph\u1ea3i l\u00e0 vi\u1ec7c s\u1eeda ch\u1eefa ho\u1eb7c thay th\u1ebf cho m\u1ed9t ren UNS hi\u1ec7n c\u00f3 kh\u00f4ng?<\/strong> N\u1ebfu b\u1ea3n v\u1ebd ghi UNS, h\u00e3y l\u00e0m \u0111\u00fang ch\u00ednh x\u00e1c. \u201cG\u1ea7n \u0111\u00fang\u201d l\u00e0 kh\u00f4ng ch\u1ea5p nh\u1eadn \u0111\u01b0\u1ee3c \u0111\u1ed1i v\u1edbi ren k\u1ebft c\u1ea5u.<\/p>\n<\/li>\n<li>\n<p><strong>C\u00f3 l\u00fd do ch\u1ee9c n\u0103ng n\u00e0o khi\u1ebfn b\u1ea1n ch\u1ecdn b\u01b0\u1edbc ren c\u1ee5 th\u1ec3 kh\u00f4ng?<\/strong> N\u1ebfu b\u1ea1n \u0111ang thi\u1ebft k\u1ebf m\u1ed9t chi ti\u1ebft m\u1edbi v\u00e0 ch\u1ecdn b\u01b0\u1edbc ren kh\u00f4ng ti\u00eau chu\u1ea9n v\u00ec l\u00fd do ch\u1ee9c n\u0103ng (t\u1ed1c \u0111\u1ed9 c\u1ea5p ph\u00f4i, c\u00e2n b\u1eb1ng \u0111\u1ed9 b\u1ec1n, v.v.), h\u00e3y ghi r\u00f5 l\u00fd do. Xem x\u00e9t li\u1ec7u m\u1ed9t lo\u1ea1i ren ti\u00eau chu\u1ea9n c\u00f3 th\u1ec3 \u0111\u1ea1t \u0111\u01b0\u1ee3c k\u1ebft qu\u1ea3 t\u01b0\u01a1ng t\u1ef1 kh\u00f4ng \u2014 UNS l\u00e0m t\u0103ng \u0111\u1ed9 ph\u1ee9c t\u1ea1p khi mua s\u1eafm.<\/p>\n<\/li>\n<\/ol>\n<p>Tuy nhi\u00ean, v\u1eabn c\u00f3 nh\u1eefng tr\u01b0\u1eddng h\u1ee3p UNS l\u00e0 l\u1ef1a ch\u1ecdn ph\u00f9 h\u1ee3p nh\u1ea5t. Trong nh\u1eefng tr\u01b0\u1eddng h\u1ee3p \u0111\u00f3, h\u00e3y ch\u1ec9 \u0111\u1ecbnh r\u00f5 r\u00e0ng, x\u00e1c minh k\u00fd hi\u1ec7u v\u00e0 l\u1ef1a ch\u1ecdn ngu\u1ed3n cung c\u1ea9n th\u1eadn.<\/p>\n<h3>Ngu\u1ed3n cung v\u00e0 \u0111\u1eb7t h\u00e0ng bul\u00f4ng ren UNS<\/h3>\n<p>Bul\u00f4ng ren UNS kh\u00f4ng ph\u1ea3i l\u00e0 m\u1eb7t h\u00e0ng c\u00f3 s\u1eb5n t\u1ea1i c\u00e1c nh\u00e0 ph\u00e2n ph\u1ed1i v\u1eadt t\u01b0 th\u00f4ng th\u01b0\u1eddng \u1edf Vi\u1ec7t Nam. \u0110\u1ec3 t\u00ecm ngu\u1ed3n cung:<\/p>\n<ul>\n<li><strong>Nh\u00e0 ph\u00e2n ph\u1ed1i bul\u00f4ng chuy\u00ean d\u1ee5ng<\/strong> \u2014 c\u00e1c c\u00f4ng ty chuy\u00ean v\u1ec1 bul\u00f4ng h\u00e0ng kh\u00f4ng, d\u1ea7u kh\u00ed ho\u1eb7c c\u00f4ng nghi\u1ec7p th\u01b0\u1eddng c\u00f3 kho UNS l\u1edbn h\u01a1n<\/li>\n<li><strong>Nh\u00e0 s\u1ea3n xu\u1ea5t bul\u00f4ng \u0111\u1eb7t h\u00e0ng theo y\u00eau c\u1ea7u<\/strong> \u2014 \u0111\u1ed1i v\u1edbi c\u00e1c s\u1ed1 l\u01b0\u1ee3ng m\u00e0 h\u00e0ng t\u1ed3n kho ti\u00eau chu\u1ea9n kh\u00f4ng \u00e1p d\u1ee5ng, c\u00e1c ch\u1ed1t gia c\u00f4ng theo b\u1ea3n v\u1ebd c\u1ee7a b\u1ea1n l\u00e0 ph\u1ed5 bi\u1ebfn<\/li>\n<li><strong>C\u1eaft ren t\u1ea1i x\u01b0\u1edfng<\/strong> \u2014 n\u1ebfu b\u1ea1n c\u00f3 kh\u1ea3 n\u0103ng ti\u1ec7n CNC ho\u1eb7c phay ren, vi\u1ec7c s\u1ea3n xu\u1ea5t ren UNS t\u1eeb ph\u00f4i bu l\u00f4ng ti\u00eau chu\u1ea9n l\u00e0 th\u1ef1c t\u1ebf cho s\u1ed1 l\u01b0\u1ee3ng nh\u1ecf<\/li>\n<\/ul>\n<p>Khi \u0111\u1eb7t h\u00e0ng, lu\u00f4n cung c\u1ea5p \u0111\u1ea7y \u0111\u1ee7 th\u00f4ng tin g\u1ecdi ra: <code>[\u0110\u01b0\u1eddng k\u00ednh]-[S\u1ed1 ren tr\u00ean inch] UNS-[C\u1ea5p \u0111\u1ed9]<\/code>, bao g\u1ed3m v\u1eadt li\u1ec7u, ho\u00e0n thi\u1ec7n v\u00e0 b\u1ea5t k\u1ef3 ti\u00eau chu\u1ea9n \u00e1p d\u1ee5ng n\u00e0o (ASTM, SAE, NASM). M\u1ed9t th\u00f4ng tin g\u1ecdi ra <code>1-14 UNS-2A, 304 SS, theo ASME B18.2.1<\/code> kh\u00f4ng g\u00e2y ra b\u1ea5t k\u1ef3 s\u1ef1 m\u01a1 h\u1ed3 n\u00e0o.<\/p>\n<h3>Nh\u1eefng l\u1ed7i ph\u1ed5 bi\u1ebfn c\u1ea7n tr\u00e1nh<\/h3>\n<p><strong>L\u1ed7i 1: Nh\u1ea7m l\u1eabn UNS v\u1edbi \u201cph\u1ed5 th\u00f4ng\u201d ho\u1eb7c \u201ckh\u00f4ng ti\u00eau chu\u1ea9n\u201d<\/strong><\/p>\n<p>UNS kh\u00f4ng c\u00f3 ngh\u0129a l\u00e0 \u201cb\u1ea5t k\u1ef3 lo\u1ea1i ren n\u00e0o\u201d ho\u1eb7c \u201ckh\u00f4ng x\u00e1c \u0111\u1ecbnh\u201d. \u0110\u00e2y l\u00e0 m\u1ed9t k\u00fd hi\u1ec7u c\u1ee5 th\u1ec3, \u0111\u01b0\u1ee3c \u0111\u1ecbnh ngh\u0129a r\u00f5 r\u00e0ng trong ASME B1.1. C\u00e1c ren \u0111\u01b0\u1ee3c g\u1eafn nh\u00e3n UNS v\u1eabn ph\u1ea3i tu\u00e2n th\u1ee7 h\u00ecnh d\u1ea1ng ren Th\u1ed1ng Nh\u1ea5t ti\u00eau chu\u1ea9n v\u1edbi t\u1ea5t c\u1ea3 c\u00e1c dung sai c\u1ee7a n\u00f3.<\/p>\n<p><strong>L\u1ed7i 2: S\u1eed d\u1ee5ng taro UNC ho\u1eb7c UNF cho l\u1ed7 ren UNS<\/strong><\/p>\n<p>N\u1ebfu b\u1ea3n v\u1ebd y\u00eau c\u1ea7u 1-14 UNS-2B v\u00e0 b\u1ea1n taro b\u1eb1ng taro 1-8 UNC ho\u1eb7c 1-12 UNF, b\u1ea1n \u0111\u00e3 t\u1ea1o ra m\u1ed9t ren kh\u00f4ng kh\u1edbp s\u1ebd kh\u00f4ng \u0103n kh\u1edbp \u0111\u00fang v\u1edbi ch\u1ed1t 1-14 UNS. Lu\u00f4n ki\u1ec3m tra s\u1ed1 ren tr\u00ean inch tr\u01b0\u1edbc khi ch\u1ecdn d\u1ee5ng c\u1ee5.<\/p>\n<p><strong>L\u1ed7i 3: Cho r\u1eb1ng c\u00e1c b\u01b0\u1edbc ren \u201cg\u1ea7n gi\u1ed1ng\u201d c\u00f3 th\u1ec3 thay th\u1ebf cho nhau<\/strong><\/p>\n<p>1-14 UNS v\u00e0 1-12 UNF kh\u00f4ng th\u1ec3 thay th\u1ebf cho nhau, m\u1eb7c d\u00f9 ch\u00fang tr\u00f4ng gi\u1ed1ng nhau khi l\u1eafp l\u1ecfng. Khi ch\u1ecbu t\u1ea3i, s\u1ef1 kh\u00f4ng kh\u1edbp n\u00e0y ch\u1ec9 t\u1ea1o ti\u1ebfp x\u00fac tr\u00ean m\u1ed9t ph\u1ea7n nh\u1ecf c\u1ee7a m\u1eb7t ren, l\u00e0m gi\u1ea3m \u0111\u00e1ng k\u1ec3 \u0111\u1ed9 b\u1ec1n m\u1ed1i n\u1ed1i. Trong c\u00e1c \u1ee9ng d\u1ee5ng th\u1ee7y l\u1ef1c, \u0111i\u1ec1u n\u00e0y c\u0169ng t\u1ea1o ra \u0111\u01b0\u1eddng r\u00f2 r\u1ec9.<\/p>\n<p><strong>L\u1ed7i 4: B\u1ecf qua c\u1ea5p \u0111\u1ed9 l\u1eafp gh\u00e9p<\/strong><\/p>\n<p>M\u1ed9t th\u00f4ng tin g\u1ecdi ra \u201c1-14 UNS\u201d m\u00e0 kh\u00f4ng c\u00f3 ch\u1ec9 \u0111\u1ecbnh c\u1ea5p \u0111\u1ed9 l\u00e0 ch\u01b0a \u0111\u1ea7y \u0111\u1ee7. Th\u1ee3 c\u01a1 kh\u00ed th\u01b0\u1eddng m\u1eb7c \u0111\u1ecbnh ch\u1ecdn 2A\/2B, nh\u01b0ng n\u1ebfu \u1ee9ng d\u1ee5ng y\u00eau c\u1ea7u c\u1ea5p \u0111\u1ed9 ch\u00ednh x\u00e1c 3, s\u1ef1 m\u01a1 h\u1ed3 n\u00e0y s\u1ebd t\u1ea1o ra r\u1ee7i ro v\u1ec1 ch\u1ea5t l\u01b0\u1ee3ng. Lu\u00f4n bao g\u1ed3m c\u1ea5p \u0111\u1ed9.<\/p>\n<p><strong>L\u1ed7i 5: Kh\u00f4ng ki\u1ec3m tra b\u1eb1ng d\u01b0\u1ee1ng ki\u1ec3m ren<\/strong><\/p>\n<p>V\u00ec ren UNS l\u00e0 kh\u00f4ng ti\u00eau chu\u1ea9n, c\u00e1c d\u01b0\u1ee1ng ki\u1ec3m k\u00edch th\u01b0\u1edbc (d\u01b0\u1ee1ng c\u1eafm go\/no-go v\u00e0 d\u01b0\u1ee1ng v\u00f2ng) ph\u1ea3i \u0111\u01b0\u1ee3c ch\u1ec9 \u0111\u1ecbnh \u0111\u00fang cho t\u1eebng lo\u1ea1i UNS c\u1ee5 th\u1ec3. B\u1ea1n kh\u00f4ng th\u1ec3 d\u00f9ng d\u01b0\u1ee1ng UNC ho\u1eb7c UNF \u0111\u1ec3 ki\u1ec3m tra ren UNS \u2014 b\u01b0\u1edbc ren s\u1ebd kh\u00e1c nhau v\u00e0 d\u01b0\u1ee1ng s\u1ebd cho k\u1ebft qu\u1ea3 sai.<\/p>\n<hr \/>\n<h2>Xu h\u01b0\u1edbng t\u01b0\u01a1ng lai trong gia c\u00f4ng ren ch\u00ednh x\u00e1c (2026+)<\/h2>\n<p><strong>\u0110o l\u01b0\u1eddng ren k\u1ef9 thu\u1eadt s\u1ed1, c\u00e1c r\u00e0ng bu\u1ed9c c\u1ee7a s\u1ea3n xu\u1ea5t b\u1ed3i \u0111\u1eafp, v\u00e0 y\u00eau c\u1ea7u ch\u1ea5t l\u01b0\u1ee3ng ng\u00e0nh h\u00e0ng kh\u00f4ng ng\u00e0y c\u00e0ng nghi\u00eam ng\u1eb7t \u0111\u1ec1u \u0111ang l\u00e0m t\u0103ng nhu c\u1ea7u v\u1ec1 t\u00e0i li\u1ec7u v\u00e0 x\u00e1c minh ren UNS ch\u00ednh x\u00e1c \u0111\u1ebfn n\u0103m 2026 v\u00e0 xa h\u01a1n.<\/strong><\/p>\n<h3>Xu h\u01b0\u1edbng x\u00e1c minh Chu\u1ed7i K\u1ef9 thu\u1eadt s\u1ed1 v\u00e0 \u0110o l\u01b0\u1eddng Ren<\/h3>\n<p>\u0110o ren \u0111ang chuy\u1ec3n t\u1eeb ph\u01b0\u01a1ng ph\u00e1p \u0111o ti\u1ebfp x\u00fac sang h\u1ec7 th\u1ed1ng qu\u00e9t quang h\u1ecdc v\u00e0 laser kh\u00f4ng ti\u1ebfp x\u00fac. M\u00e1y \u0111o t\u1ecda \u0111\u1ed9 (CMM) \u0111\u01b0\u1ee3c trang b\u1ecb \u0111\u1ea7u d\u00f2 qu\u00e9t hi\u1ec7n c\u00f3 th\u1ec3 \u0111o b\u01b0\u1edbc ren UNS, g\u00f3c s\u01b0\u1eddn v\u00e0 b\u00e1n k\u00ednh \u0111\u00e1y ch\u1ec9 trong m\u1ed9t chu tr\u00ecnh t\u1ef1 \u0111\u1ed9ng \u2014 thu th\u1eadp d\u1eef li\u1ec7u m\u00e0 c\u00e1c th\u01b0\u1edbc \u0111o go\/no-go truy\u1ec1n th\u1ed1ng kh\u00f4ng th\u1ec3 cung c\u1ea5p.<\/p>\n<p>\u0110\u1ed1i v\u1edbi ren UNS, \u0111i\u1ec1u n\u00e0y quan tr\u1ecdng v\u00ec m\u1ed7i t\u1ed5 h\u1ee3p UNS \u0111\u1ec1u \u0111\u1ed9c nh\u1ea5t. Kh\u00f4ng c\u00f3 th\u01b0\u1edbc \u0111o n\u00e0o trong danh m\u1ee5c \u0111\u1ec3 l\u1ea5y ra s\u1eed d\u1ee5ng. C\u00e1c x\u01b0\u1edfng \u0111\u1ea7u t\u01b0 v\u00e0o kh\u1ea3 n\u0103ng \u0111o ren b\u1eb1ng CMM c\u00f3 th\u1ec3 x\u00e1c minh ren UNS m\u00e0 kh\u00f4ng c\u1ea7n th\u1eddi gian ch\u1edd v\u00e0 chi ph\u00ed \u0111\u1eb7t l\u00e0m th\u01b0\u1edbc \u0111o ri\u00eang. Theo <a href=\"https:\/\/www.nist.gov\/laboratories\/lab-offices\/physical-measurement-laboratory\" target=\"_blank\" rel=\"noopener\">T\u00e0i nguy\u00ean \u0111o l\u01b0\u1eddng k\u1ef9 thu\u1eadt c\u1ee7a NIST<\/a>, c\u00f4ng ngh\u1ec7 quang h\u1ecdc ti\u00ean ti\u1ebfn hi\u1ec7n c\u00f3 th\u1ec3 ph\u00e2n gi\u1ea3i chi ti\u1ebft h\u00ecnh h\u1ecdc ren d\u01b0\u1edbi 1 micron \u2014 v\u01b0\u1ee3t xa d\u1ea3i dung sai c\u1ee7a c\u1ea3 ren Chu\u1ea9n Th\u1ed1ng Nh\u1ea5t c\u1ea5p 3.<\/p>\n<h3>S\u1ea3n xu\u1ea5t ph\u1ee5 gia v\u00e0 Ti\u00eau chu\u1ea9n Ren<\/h3>\n<p>Khi s\u1ea3n xu\u1ea5t ph\u1ee5 gia kim lo\u1ea1i (AM\/in 3D) ng\u00e0y c\u00e0ng ph\u1ed5 bi\u1ebfn trong ng\u00e0nh h\u00e0ng kh\u00f4ng v\u0169 tr\u1ee5 v\u00e0 s\u1ea3n xu\u1ea5t c\u00f4ng nghi\u1ec7p, v\u1ea5n \u0111\u1ec1 v\u1ec1 ren in \u2014 bao g\u1ed3m c\u1ea3 ren UNS \u2014 ng\u00e0y c\u00e0ng \u0111\u01b0\u1ee3c quan t\u00e2m. \u1ee6y ban AM c\u1ee7a ASTM International \u0111ang t\u00edch c\u1ef1c ph\u00e1t tri\u1ec3n h\u01b0\u1edbng d\u1eabn cho c\u00e1c \u0111\u1eb7c t\u00ednh ren tr\u00ean c\u00e1c b\u1ed9 ph\u1eadn kim lo\u1ea1i in.<\/p>\n<p>\u0110\u1ed3ng thu\u1eadn hi\u1ec7n t\u1ea1i c\u1ee7a ng\u00e0nh: <strong>in v\u1edbi dung sai th\u00f4, sau \u0111\u00f3 gia c\u00f4ng \u0111\u1ec3 \u0111\u1ea1t th\u00f4ng s\u1ed1 ren cu\u1ed1i c\u00f9ng.<\/strong> \u0110i\u1ec1u n\u00e0y \u00e1p d\u1ee5ng cho ren UNS c\u0169ng nh\u01b0 c\u00e1c lo\u1ea1i kh\u00e1c. H\u00ecnh d\u1ea1ng ren \u0111\u01b0\u1ee3c ho\u00e0n thi\u1ec7n b\u1eb1ng ti\u1ec7n ho\u1eb7c phay CNC; quy tr\u00ecnh AM t\u1ea1o h\u00ecnh g\u1ea7n \u0111\u00fang. Quy tr\u00ecnh n\u00e0y \u0111\u1ea3m b\u1ea3o \u0111\u1ed9 ch\u00ednh x\u00e1c c\u1ee7a ch\u1ec9 \u0111\u1ecbnh UNS \u0111\u1ed3ng th\u1eddi t\u1eadn d\u1ee5ng s\u1ef1 t\u1ef1 do h\u00ecnh h\u1ecdc c\u1ee7a c\u00f4ng ngh\u1ec7 ph\u1ee5 gia cho h\u00ecnh d\u1ea1ng xung quanh c\u1ee7a chi ti\u1ebft.<\/p>\n<p><strong>B\u1ea2NG 3 \u2014 Tham kh\u1ea3o l\u1ef1a ch\u1ecdn ren cho thi\u1ebft k\u1ebf k\u1ef9 thu\u1eadt n\u0103m 2026<\/strong><\/p>\n<table>\n<thead>\n<tr>\n<th>K\u1ecbch b\u1ea3n thi\u1ebft k\u1ebf<\/th>\n<th>Ren khuy\u1ebfn ngh\u1ecb<\/th>\n<th>L\u00fd do<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Li\u00ean k\u1ebft k\u1ebft c\u1ea5u chung, m\u1ecdi v\u1eadt li\u1ec7u<\/td>\n<td>UNC<\/td>\n<td>T\u1ed1i \u0111a h\u00f3a ngu\u1ed3n d\u1ee5ng c\u1ee5, chi ph\u00ed th\u1ea5p nh\u1ea5t<\/td>\n<\/tr>\n<tr>\n<td>M\u00f4i tr\u01b0\u1eddng rung m\u1ea1nh, k\u1eb9p ch\u1eb7t tinh<\/td>\n<td>UNF<\/td>\n<td>TPI cao h\u01a1n = kh\u1ea3 n\u0103ng ch\u1ed1ng rung t\u1ed1t h\u01a1n<\/td>\n<\/tr>\n<tr>\n<td>T\u01b0\u1eddng r\u1ea5t m\u1ecfng, c\u01a1 c\u1ea5u ch\u00ednh x\u00e1c<\/td>\n<td>UNEF<\/td>\n<td>B\u01b0\u1edbc ren nh\u1ecf gi\u1ea3m thi\u1ec3u l\u01b0\u1ee3ng v\u1eadt li\u1ec7u b\u1ecb lo\u1ea1i b\u1ecf<\/td>\n<\/tr>\n<tr>\n<td>L\u1eafp l\u1ea1i cho chi ti\u1ebft c\u0169, b\u01b0\u1edbc ren kh\u00f4ng ti\u00eau chu\u1ea9n<\/td>\n<td>UNS<\/td>\n<td>Kh\u1edbp ch\u00ednh x\u00e1c v\u1edbi ch\u00fa th\u00edch hi\u1ec7n c\u00f3<\/td>\n<\/tr>\n<tr>\n<td>Thanh xi lanh th\u1ee7y l\u1ef1c, \u0111\u01b0\u1eddng k\u00ednh 1\u2033 tr\u1edf l\u00ean<\/td>\n<td>UNS (v\u00ed d\u1ee5, 1-14)<\/td>\n<td>C\u00e2n b\u1eb1ng gi\u1eefa \u0111\u1ed9 \u0103n kh\u1edbp v\u00e0 \u0111\u1ed9 b\u1ec1n<\/td>\n<\/tr>\n<tr>\n<td>M\u1eb7t b\u00edch b\u00ecnh \u00e1p l\u1ef1c, \u0111\u01b0\u1eddng k\u00ednh 2\u2033 tr\u1edf l\u00ean<\/td>\n<td>UNS (v\u00ed d\u1ee5, 2-12)<\/td>\n<td>Kh\u00f4ng c\u00f3 UNC\/UNF n\u00e0o c\u00f3 12 TPI \u1edf \u0111\u01b0\u1eddng k\u00ednh n\u00e0y<\/td>\n<\/tr>\n<tr>\n<td>Quan tr\u1ecdng v\u1ec1 m\u1ecfi trong ng\u00e0nh h\u00e0ng kh\u00f4ng v\u0169 tr\u1ee5<\/td>\n<td>UNR (g\u1ed1c tr\u00f2n)<\/td>\n<td>Gi\u1ea3m t\u1eadp trung \u1ee9ng su\u1ea5t so v\u1edbi g\u1ed1c ph\u1eb3ng<\/td>\n<\/tr>\n<tr>\n<td>C\u01a1 c\u1ea5u ch\u00ednh x\u00e1c gia c\u00f4ng CNC<\/td>\n<td>UNS (b\u01b0\u1edbc ren t\u00f9y ch\u1ec9nh)<\/td>\n<td>Ch\u1ecdn b\u01b0\u1edbc ren cho t\u1ed1c \u0111\u1ed9 c\u1ea5p li\u1ec7u \/ ch\u1ee9c n\u0103ng mong mu\u1ed1n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<hr \/>\n<h2>C\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p<\/h2>\n<p><strong>H\u1ecfi: \u0110\u00e2y l\u00e0 ren UNC hay UNS \u2014 s\u1ef1 kh\u00e1c bi\u1ec7t l\u00e0 g\u00ec?<\/strong><\/p>\n<p>UNC (Ren th\u00f4 qu\u1ed1c gia th\u1ed1ng nh\u1ea5t) l\u00e0 m\u1ed9t lo\u1ea1t b\u01b0\u1edbc ren ti\u00eau chu\u1ea9n: m\u1ed7i \u0111\u01b0\u1eddng k\u00ednh ch\u1ec9 c\u00f3 m\u1ed9t b\u01b0\u1edbc ren UNC (v\u00ed d\u1ee5, 1\/4-20 UNC). UNS (Ren \u0111\u1eb7c bi\u1ec7t qu\u1ed1c gia th\u1ed1ng nh\u1ea5t) d\u00e0nh cho c\u00e1c b\u01b0\u1edbc ren kh\u00f4ng ti\u00eau chu\u1ea9n \u2014 c\u00f9ng d\u1ea1ng ren Unified, nh\u01b0ng b\u01b0\u1edbc ren kh\u00f4ng n\u1eb1m trong b\u1ea3ng UNC, UNF ho\u1eb7c UNEF. N\u1ebfu m\u1ed9t ch\u1ed1t 1\/4 inch c\u00f3 24 TPI (kh\u00f4ng ph\u1ea3i 20 UNC ho\u1eb7c 28 UNF), \u0111\u00f3 l\u00e0 UNS.<\/p>\n<p><strong>H\u1ecfi: \u201cUNS\u201d tr\u00ean m\u0169i tar ngh\u0129a l\u00e0 g\u00ec?<\/strong><\/p>\n<p>M\u1ed9t m\u0169i tar \u0111\u01b0\u1ee3c \u0111\u00e1nh d\u1ea5u UNS \u0111\u01b0\u1ee3c m\u00e0i \u0111\u1ec3 c\u1eaft ren Unified v\u1edbi m\u1ed9t b\u01b0\u1edbc ren kh\u00f4ng ti\u00eau chu\u1ea9n c\u1ee5 th\u1ec3. Kh\u00e1c v\u1edbi m\u0169i tar UNC ho\u1eb7c UNF \u2014 v\u1ed1n ph\u00f9 h\u1ee3p v\u1edbi nhi\u1ec1u t\u1ed5 h\u1ee3p ti\u00eau chu\u1ea9n \u2014 m\u0169i tar UNS \u0111\u01b0\u1ee3c ch\u1ebf t\u1ea1o ri\u00eang cho m\u1ed9t t\u1ed5 h\u1ee3p \u0111\u01b0\u1eddng k\u00ednh-TPI duy nh\u1ea5t. Lu\u00f4n x\u00e1c minh r\u1eb1ng m\u0169i tar UNS ph\u00f9 h\u1ee3p v\u1edbi ch\u00fa th\u00edch tr\u00ean b\u1ea3n v\u1ebd c\u1ee7a b\u1ea1n, bao g\u1ed3m c\u1ea3 c\u1ea5p \u0111\u1ed9 kh\u1edbp.<\/p>\n<p><strong>H\u1ecfi: UNS c\u00f3 gi\u1ed1ng UNF kh\u00f4ng?<\/strong><\/p>\n<p>Kh\u00f4ng. UNF (Ren m\u1ecbn qu\u1ed1c gia th\u1ed1ng nh\u1ea5t) l\u00e0 m\u1ed9t lo\u1ea1t ti\u00eau chu\u1ea9n v\u1edbi c\u00e1c b\u01b0\u1edbc ren c\u1ed1 \u0111\u1ecbnh \u1edf m\u1ed7i \u0111\u01b0\u1eddng k\u00ednh. UNS l\u00e0 k\u00fd hi\u1ec7u \u201c\u0111\u1eb7c bi\u1ec7t\u201d cho c\u00e1c b\u01b0\u1edbc ren kh\u00f4ng xu\u1ea5t hi\u1ec7n trong b\u1ea5t k\u1ef3 lo\u1ea1t ti\u00eau chu\u1ea9n n\u00e0o. Tuy nhi\u00ean, m\u1ed9t ren ban \u0111\u1ea7u c\u00f3 v\u1ebb l\u00e0 UNS c\u00f3 th\u1ec3 th\u1ef1c ra l\u00e0 UNF n\u1ebfu b\u01b0\u1edbc ren ph\u00f9 h\u1ee3p v\u1edbi b\u1ea3ng UNF cho \u0111\u01b0\u1eddng k\u00ednh \u0111\u00f3 \u2014 lu\u00f4n ki\u1ec3m tra theo ASME B1.1.<\/p>\n<p><strong>H\u1ecfi: Ren 1-14 UNS l\u00e0 g\u00ec?<\/strong><\/p>\n<p>1-14 UNS l\u00e0 ren c\u00f3 \u0111\u01b0\u1eddng k\u00ednh 1 inch v\u1edbi 14 v\u00f2ng ren tr\u00ean m\u1ed7i inch, \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 Unified National Special v\u00ec \u1edf \u0111\u01b0\u1eddng k\u00ednh 1 inch, UNC y\u00eau c\u1ea7u 8 TPI v\u00e0 UNF y\u00eau c\u1ea7u 12 TPI \u2014 14 TPI kh\u00f4ng ph\u00f9 h\u1ee3p v\u1edbi b\u1ea5t k\u1ef3 ti\u00eau chu\u1ea9n n\u00e0o. Lo\u1ea1i ren n\u00e0y c\u1ef1c k\u1ef3 ph\u1ed5 bi\u1ebfn trong xi lanh th\u1ee7y l\u1ef1c v\u00e0 thi\u1ebft b\u1ecb h\u1ea1ng n\u1eb7ng khi c\u1ea7n b\u01b0\u1edbc ren trung b\u00ecnh \u1edf \u0111\u01b0\u1eddng k\u00ednh l\u1edbn.<\/p>\n<p><strong>H\u1ecfi: T\u00f4i c\u00f3 th\u1ec3 d\u00f9ng taro UNC cho l\u1ed7 y\u00eau c\u1ea7u UNS kh\u00f4ng?<\/strong><\/p>\n<p>Ch\u1ec9 khi b\u01b0\u1edbc ren UNC t\u00ecnh c\u1edd tr\u00f9ng v\u1edbi th\u00f4ng s\u1ed1 UNS, \u0111i\u1ec1u n\u00e0y v\u1ec1 m\u1eb7t \u0111\u1ecbnh ngh\u0129a l\u00e0 kh\u00f4ng th\u1ec3 \u2014 n\u1ebfu b\u01b0\u1edbc ren tr\u00f9ng UNC, ren \u0111\u00f3 s\u1ebd \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 UNC. Kh\u00f4ng bao gi\u1edd thay th\u1ebf taro UNC ho\u1eb7c UNF cho ren UNS m\u00e0 kh\u00f4ng x\u00e1c nh\u1eadn c\u00e1c b\u01b0\u1edbc ren ho\u00e0n to\u00e0n gi\u1ed1ng nhau. Trong tr\u01b0\u1eddng h\u1ee3p t\u1ed1t nh\u1ea5t, ren kh\u00f4ng kh\u1edbp s\u1ebd b\u1ecb l\u1ecfng; t\u1ec7 nh\u1ea5t, n\u00f3 s\u1ebd b\u1ecb h\u1ecfng khi ch\u1ecbu t\u1ea3i.<\/p>\n<p><strong>H\u1ecfi: T\u00f4i c\u00f3 th\u1ec3 t\u00ecm b\u1ea3ng tra ren UNS \u1edf \u0111\u00e2u?<\/strong><\/p>\n<p>Ngu\u1ed3n tham kh\u1ea3o ch\u00ednh th\u1ee9c l\u00e0 ASME B1.1, c\u00f3 th\u1ec3 l\u1ea5y t\u1eeb ASME.org. \u0110\u1ec3 tham kh\u1ea3o th\u1ef1c t\u1ebf, c\u00e1c nh\u00e0 cung c\u1ea5p d\u1ee5ng c\u1ee5 l\u1edbn (OSG, Emuge, Greenfield) \u0111\u1ec1u c\u00f4ng b\u1ed1 b\u1ea3ng tra cho c\u00e1c lo\u1ea1i taro UNS c\u1ee7a h\u1ecd. L\u01b0u \u00fd r\u1eb1ng kh\u00f4ng c\u00f3 b\u1ea3ng tra UNS n\u00e0o l\u00e0 \u201c\u0111\u1ea7y \u0111\u1ee7\u201d \u2014 UNS \u0111\u01b0\u1ee3c x\u00e1c \u0111\u1ecbnh b\u1edfi nh\u1eefng g\u00ec n\u00f3 kh\u00f4ng ph\u1ea3i, ch\u1ee9 kh\u00f4ng ph\u1ea3i b\u1edfi m\u1ed9t danh s\u00e1ch k\u00edch th\u01b0\u1edbc c\u1ed1 \u0111\u1ecbnh.<\/p>\n<p><strong>H\u1ecfi: Ren UNS c\u00f3 ph\u1ea3i l\u00e0 ren h\u1ec7 m\u00e9t kh\u00f4ng?<\/strong><\/p>\n<p>Kh\u00f4ng. UNS thu\u1ed9c h\u1ec7 ren Inch Unified. T\u1ea5t c\u1ea3 \u0111\u01b0\u1eddng k\u00ednh v\u00e0 b\u01b0\u1edbc ren \u0111\u1ec1u t\u00ednh b\u1eb1ng inch v\u00e0 s\u1ed1 v\u00f2ng ren tr\u00ean m\u1ed7i inch (TPI). H\u1ec7 th\u1ed1ng t\u01b0\u01a1ng \u0111\u01b0\u01a1ng h\u1ec7 m\u00e9t l\u00e0 ren ISO\/DIN (d\u00f2ng M), s\u1eed d\u1ee5ng \u0111\u01b0\u1eddng k\u00ednh v\u00e0 b\u01b0\u1edbc ren t\u00ednh b\u1eb1ng milim\u00e9t. N\u1ebfu b\u1ea1n c\u1ea7n b\u01b0\u1edbc ren \u0111\u1eb7c bi\u1ec7t h\u1ec7 m\u00e9t, n\u00f3 s\u1ebd \u0111\u01b0\u1ee3c k\u00fd hi\u1ec7u kh\u00e1c \u2014 th\u01b0\u1eddng l\u00e0 ren h\u1ec7 m\u00e9t kh\u00f4ng ti\u00eau chu\u1ea9n theo ISO 68-1.<\/p>\n<p><img decoding=\"async\" alt=\"Ren UNS \u2014 minh h\u1ecda k\u1ebft th\u00fac th\u1ec3 hi\u1ec7n b\u1ed9 bulong v\u00e0 \u0111ai \u1ed1c th\u00e9p kh\u00f4ng g\u1ec9 gia c\u00f4ng ch\u00ednh x\u00e1c c\u00f3 ren UNS trong m\u00f4i tr\u01b0\u1eddng x\u01b0\u1edfng\" src=\"https:\/\/productionscrews.com\/wp-content\/uploads\/2026\/05\/uns-thread-closing.png\" \/><\/p>\n<hr \/>\n<h2>K\u1ebft lu\u1eadn<\/h2>\n<p>Ren UNS l\u00e0 m\u1ed9t trong nh\u1eefng ch\u1ee7 \u0111\u1ec1 t\u01b0\u1edfng nh\u01b0 xa l\u1ea1 cho \u0111\u1ebfn khi b\u1ea1n \u0111\u1ee9ng tr\u01b0\u1edbc m\u00e1y v\u1edbi b\u1ea3n v\u1ebd c\u00f3 k\u00fd hi\u1ec7u m\u00e0 b\u1ea1n kh\u00f4ng nh\u1eadn ra \u2014 v\u00e0 l\u00fac \u0111\u00f3 n\u00f3 tr\u1edf n\u00ean r\u1ea5t quan tr\u1ecdng. \u0110i\u1ec1u c\u1ed1t l\u00f5i c\u1ea7n nh\u1edb: UNS kh\u00f4ng ph\u1ea3i l\u00e0 lo\u1ea1i hi\u1ebfm, kh\u00f4ng ph\u1ea3i ch\u1ea5t l\u01b0\u1ee3ng th\u1ea5p, v\u00e0 c\u0169ng kh\u00f4ng ph\u1ea3i \u201cphi ti\u00eau chu\u1ea9n\u201d theo ngh\u0129a m\u01a1 h\u1ed3. \u0110\u00e2y l\u00e0 danh m\u1ee5c ch\u00ednh th\u1ee9c c\u1ee7a ti\u00eau chu\u1ea9n ren Unified cho c\u00e1c b\u01b0\u1edbc ren kh\u00f4ng ph\u00f9 h\u1ee3p UNC, UNF ho\u1eb7c UNEF, \u0111\u01b0\u1ee3c qu\u1ea3n l\u00fd b\u1edfi c\u00f9ng quy t\u1eafc ASME B1.1 v\u00e0 \u0111o b\u1eb1ng c\u00f9ng ph\u01b0\u01a1ng ph\u00e1p.<\/p>\n<p>Nh\u1eefng \u0111i\u1ec1u th\u1ef1c t\u1ebf nh\u1ea5t c\u1ea7n nh\u1edb: lu\u00f4n kh\u1edbp \u0111\u1ea7y \u0111\u1ee7 th\u00f4ng s\u1ed1 (\u0111\u01b0\u1eddng k\u00ednh, TPI, d\u00f2ng ren, c\u1ea5p \u0111\u1ed9), kh\u00f4ng bao gi\u1edd thay th\u1ebf taro d\u00f2ng ti\u00eau chu\u1ea9n cho l\u1ed7 UNS, s\u1eed d\u1ee5ng phay ren cho c\u00e1c c\u00f4ng vi\u1ec7c UNS \u0111\u01a1n l\u1ebb, v\u00e0 \u0111\u1eb7t l\u00e0m d\u01b0\u1ee1ng ki\u1ec3m ri\u00eang n\u1ebfu b\u1ea1n s\u1ea3n xu\u1ea5t ren UNS s\u1ed1 l\u01b0\u1ee3ng l\u1edbn. N\u1eafm v\u1eefng nh\u1eefng nguy\u00ean t\u1eafc n\u00e0y, ren UNS s\u1ebd d\u1ec5 qu\u1ea3n l\u00fd nh\u01b0 b\u1ea5t k\u1ef3 ti\u00eau chu\u1ea9n bulong n\u00e0o kh\u00e1c.<\/p>\n<p>N\u1ebfu x\u01b0\u1edfng c\u1ee7a b\u1ea1n th\u01b0\u1eddng xuy\u00ean g\u1eb7p k\u00fd hi\u1ec7u ren UNS \u2014 \u0111\u1eb7c bi\u1ec7t trong l\u0129nh v\u1ef1c h\u00e0ng kh\u00f4ng, d\u1ea7u kh\u00ed ho\u1eb7c xi lanh th\u1ee7y l\u1ef1c \u2014 n\u00ean x\u00e2y d\u1ef1ng th\u01b0 vi\u1ec7n tham kh\u1ea3o c\u00e1c k\u00edch th\u01b0\u1edbc ph\u1ed5 bi\u1ebfn nh\u1ea5t v\u00e0 trang b\u1ecb \u00edt nh\u1ea5t m\u1ed9t b\u1ed9 d\u01b0\u1ee1ng ki\u1ec3m go\/no-go cho c\u00e1c b\u01b0\u1edbc ren th\u01b0\u1eddng g\u1eb7p. \u0110\u1ea7u t\u01b0 ban \u0111\u1ea7u n\u00e0y s\u1ebd nhanh ch\u00f3ng mang l\u1ea1i hi\u1ec7u qu\u1ea3 nh\u1edd gi\u1ea3m ph\u1ebf ph\u1ea9m v\u00e0 t\u0103ng t\u1ed1c ki\u1ec3m tra s\u1ea3n ph\u1ea9m \u0111\u1ea7u ti\u00ean.<\/p>","protected":false},"excerpt":{"rendered":"<p>H\u01b0\u1edbng d\u1eabn \u0111\u1ea7y \u0111\u1ee7 v\u1ec1 ren UNS (Unified National Special): th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt, b\u1ea3ng k\u00edch th\u01b0\u1edbc, gi\u1ea3i m\u00e3 k\u00fd hi\u1ec7u, \u1ee9ng d\u1ee5ng trong ng\u00e0nh, v\u00e0 c\u00e1ch l\u1ef1a ch\u1ecdn c\u0169ng nh\u01b0 t\u00ecm ngu\u1ed3n bulong ren UNS.<\/p>","protected":false},"author":1,"featured_media":3779,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-3783","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-screws-flange-tutorial"],"_links":{"self":[{"href":"https:\/\/productionscrews.com\/vi\/wp-json\/wp\/v2\/posts\/3783","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/productionscrews.com\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/productionscrews.com\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/productionscrews.com\/vi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/productionscrews.com\/vi\/wp-json\/wp\/v2\/comments?post=3783"}],"version-history":[{"count":1,"href":"https:\/\/productionscrews.com\/vi\/wp-json\/wp\/v2\/posts\/3783\/revisions"}],"predecessor-version":[{"id":3784,"href":"https:\/\/productionscrews.com\/vi\/wp-json\/wp\/v2\/posts\/3783\/revisions\/3784"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/productionscrews.com\/vi\/wp-json\/wp\/v2\/media\/3779"}],"wp:attachment":[{"href":"https:\/\/productionscrews.com\/vi\/wp-json\/wp\/v2\/media?parent=3783"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/productionscrews.com\/vi\/wp-json\/wp\/v2\/categories?post=3783"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/productionscrews.com\/vi\/wp-json\/wp\/v2\/tags?post=3783"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}