{"id":5721,"date":"2026-09-11T10:00:57","date_gmt":"2026-09-11T01:00:57","guid":{"rendered":"https:\/\/ohtavn.com\/?post_type=media&p=5721"},"modified":"2026-09-09T12:27:36","modified_gmt":"2026-09-09T03:27:36","slug":"what-is-the-strength-classification-of-screws","status":"publish","type":"media","link":"https:\/\/ohtavn.com\/vi\/media\/what-is-the-strength-classification-of-screws\/","title":{"rendered":"C\u1ea5p b\u1ec1n c\u1ee7a bu l\u00f4ng, \u1ed1c v\u00edt l\u00e0 g\u00ec? Ti\u00eau chu\u1ea9n v\u00e0 c\u00e1ch l\u1ef1a ch\u1ecdn ph\u00f9 h\u1ee3p trong ng\u00e0nh s\u1ea3n xu\u1ea5t"},"content":{"rendered":"
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L\u1eddi m\u1edf \u0111\u1ea7u<\/h3>\n<\/div>\n
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Trong m\u00f4i tr\u01b0\u1eddng s\u1ea3n xu\u1ea5t, vi\u1ec7c h\u1ecfng h\u00f3c d\u00f9 ch\u1ec9 m\u1ed9t chi\u1ebfc “v\u00edt” c\u0169ng c\u00f3 th\u1ec3 l\u00e0m m\u1ea5t \u0111i s\u1ef1 tin c\u1eady c\u1ee7a to\u00e0n b\u1ed9 s\u1ea3n ph\u1ea9m, v\u00e0 \u0111\u00f4i khi d\u1eabn \u0111\u1ebfn nh\u1eefng tai n\u1ea1n nghi\u00eam tr\u1ecdng. \u0110\u1eb7c bi\u1ec7t \u0111\u1ed1i v\u1edbi c\u00e1c m\u00e1y m\u00f3c c\u00f4ng nghi\u1ec7p c\u00f3 \u0111\u1ed9 rung l\u1eafc m\u1ea1nh hay c\u00e1c thi\u1ebft b\u1ecb h\u1ea1 t\u1ea7ng s\u1eed d\u1ee5ng trong m\u00f4i tr\u01b0\u1eddng kh\u1eafc nghi\u1ec7t, vi\u1ec7c l\u1ef1a ch\u1ecdn “C\u1ea5p b\u1ec1n” (Strength Class) ph\u00f9 h\u1ee3p l\u00e0 \u01b0u ti\u00ean h\u00e0ng \u0111\u1ea7u trong thi\u1ebft k\u1ebf v\u00e0 thu mua.<\/p>\n<\/div>\n

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Trong b\u00e0i vi\u1ebft n\u00e0y, ch\u00fang t\u00f4i s\u1ebd gi\u1ea3i th\u00edch m\u1ed9t c\u00e1ch to\u00e0n di\u1ec7n cho ban l\u00e3nh \u0111\u1ea1o, ng\u01b0\u1eddi ph\u1ee5 tr\u00e1ch thu mua v\u00e0 c\u00e1c k\u1ef9 s\u01b0 t\u1ea1i hi\u1ec7n tr\u01b0\u1eddng trong ng\u00e0nh s\u1ea3n xu\u1ea5t, t\u1eeb nh\u1eefng ki\u1ebfn th\u1ee9c c\u01a1 b\u1ea3n v\u1ec1 c\u1ea5p b\u1ec1n c\u1ee7a v\u00edt \u0111\u1ebfn c\u00e1c c\u00f4ng th\u1ee9c t\u00ednh to\u00e1n thi\u1ebft y\u1ebfu, v\u00e0 c\u1ea3 qu\u1ea3n l\u00fd ch\u1ea5t l\u01b0\u1ee3ng m\u1ed1i n\u1ed1i b\u1eb1ng c\u00f4ng ngh\u1ec7 IoT \u0111ang thu h\u00fat s\u1ef1 ch\u00fa \u00fd g\u1ea7n \u0111\u00e2y. H\u01a1n n\u1eefa, ch\u00fang t\u00f4i c\u0169ng s\u1ebd \u0111\u1ec1 c\u1eadp \u0111\u1ebfn m\u00f4i tr\u01b0\u1eddng thu mua t\u1ea1i Vi\u1ec7t Nam – n\u01a1i \u0111ang c\u00f3 t\u1ed1c \u0111\u1ed9 c\u00f4ng nghi\u1ec7p h\u00f3a nhanh ch\u00f3ng, v\u00e0 gi\u1edbi thi\u1ec7u c\u00e1ch th\u1ee9c c\u00e1c gi\u1ea3i ph\u00e1p c\u1ee7a Ohta Vi\u1ec7t Nam gi\u00fap c\u00e2n b\u1eb1ng gi\u1eefa t\u1ed1i \u01b0u h\u00f3a chi ph\u00ed v\u00e0 \u0111\u1ea3m b\u1ea3o ch\u1ea5t l\u01b0\u1ee3ng. Hy v\u1ecdng th\u00f4ng qua b\u00e0i vi\u1ebft n\u00e0y, qu\u00fd v\u1ecb s\u1ebd c\u00f3 \u0111\u01b0\u1ee3c nh\u1eefng \u0111\u1ecbnh h\u01b0\u1edbng thi\u1ebft k\u1ebf m\u1ed1i n\u1ed1i an to\u00e0n v\u00e0 hi\u1ec7u qu\u1ea3.<\/p>\n<\/div>\n

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C\u01a1 b\u1ea3n v\u1ec1 c\u1ea5p b\u1ec1n v\u00e0 t\u1ea7m quan tr\u1ecdng c\u1ee7a ti\u00eau chu\u1ea9n qu\u1ed1c t\u1ebf<\/h3>\n<\/div>\n
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\u00dd ngh\u0129a c\u1ee7a c\u00e1c con s\u1ed1: \u201cGi\u1edbi h\u1ea1n b\u1ec1n k\u00e9o\u201d v\u00e0 \u201cGi\u1edbi h\u1ea1n ch\u1ea3y\u201d<\/h4>\n<\/div>\n
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Nh\u1eefng con s\u1ed1 nh\u01b0 “4.8” hay “10.9” \u0111\u01b0\u1ee3c kh\u1eafc tr\u00ean \u0111\u1ea7u v\u00edt ho\u1eb7c tr\u00ean bao b\u00ec ch\u00ednh l\u00e0 “C\u1ea5p b\u1ec1n”. Nh\u1eefng con s\u1ed1 n\u00e0y l\u00e0 ng\u00f4n ng\u1eef chung to\u00e0n c\u1ea7u cho bi\u1ebft chi\u1ebfc v\u00edt \u0111\u00f3 c\u00f3 th\u1ec3 ch\u1ecbu \u0111\u01b0\u1ee3c t\u1ea3i tr\u1ecdng bao nhi\u00eau.<\/p>\n<\/div>\n

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V\u00ed d\u1ee5, v\u1edbi k\u00fd hi\u1ec7u “10.9”, con s\u1ed1 “10” \u0111\u1ea7u ti\u00ean bi\u1ec3u th\u1ecb Gi\u1edbi h\u1ea1n b\u1ec1n k\u00e9o (Nominal Tensile Strength), ngh\u0129a l\u00e0 n\u00f3 c\u00f3 th\u1ec3 ch\u1ecbu \u0111\u01b0\u1ee3c l\u1ef1c l\u00ean \u0111\u1ebfn 1,000 N\/mm\u00b2. Con s\u1ed1 “.9” ti\u1ebfp theo cho bi\u1ebft Gi\u1edbi h\u1ea1n ch\u1ea3y (Yield Point) ho\u1eb7c \u1ee9ng su\u1ea5t d\u01b0 b\u1eb1ng 90% gi\u1edbi h\u1ea1n b\u1ec1n k\u00e9o. N\u00f3i c\u00e1ch kh\u00e1c, n\u1ebfu t\u1ea3i tr\u1ecdng t\u1eeb 900 N\/mm\u00b2 tr\u1edf l\u00ean t\u00e1c \u0111\u1ed9ng v\u00e0o, v\u00edt s\u1ebd b\u1ecb “bi\u1ebfn d\u1ea1ng v\u0129nh vi\u1ec5n” v\u00e0 kh\u00f4ng th\u1ec3 tr\u1edf l\u1ea1i h\u00ecnh d\u1ea1ng ban \u0111\u1ea7u. N\u1ebfu th\u1ef1c hi\u1ec7n vi\u1ec7c l\u1eafp si\u1ebft v\u01b0\u1ee3t qu\u00e1 th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt (over-spec) m\u00e0 kh\u00f4ng bi\u1ebft \u0111i\u1ec1u n\u00e0y s\u1ebd g\u00e2y t\u0103ng chi ph\u00ed, ng\u01b0\u1ee3c l\u1ea1i n\u1ebfu d\u01b0\u1edbi th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt (under-spec) th\u00ec r\u1ee7i ro \u0111\u1ee9t g\u00e3y s\u1ebd t\u0103ng v\u1ecdt.<\/p>\n<\/div>\n

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S\u1ef1 th\u1ed1ng nh\u1ea5t gi\u1eefa Ti\u00eau chu\u1ea9n C\u00f4ng nghi\u1ec7p Nh\u1eadt B\u1ea3n (JIS) v\u00e0 Ti\u00eau chu\u1ea9n Qu\u1ed1c t\u1ebf (ISO)<\/h4>\n<\/div>\n
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Hi\u1ec7n nay, Ti\u00eau chu\u1ea9n C\u00f4ng nghi\u1ec7p Nh\u1eadt B\u1ea3n (JIS) \u0111\u01b0\u1ee3c tham chi\u1ebfu t\u1ea1i nhi\u1ec1u x\u01b0\u1edfng s\u1ea3n xu\u1ea5t, nh\u01b0ng ph\u1ea7n l\u1edbn trong s\u1ed1 \u0111\u00f3 \u0111\u1ec1u tu\u00e2n th\u1ee7 ti\u00eau chu\u1ea9n qu\u1ed1c t\u1ebf ISO 898-1. Trong th\u1eddi \u0111\u1ea1i tri\u1ec3n khai chu\u1ed7i cung \u1ee9ng to\u00e0n c\u1ea7u hi\u1ec7n nay, vi\u1ec7c hi\u1ec3u r\u00f5 c\u00e1c ti\u00eau chu\u1ea9n qu\u1ed1c t\u1ebf n\u00e0y l\u00e0 kh\u00f4ng th\u1ec3 thi\u1ebfu.<\/p>\n<\/div>\n

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\u0110\u1eb7c bi\u1ec7t khi thu mua linh ki\u1ec7n t\u1ea1i c\u00e1c c\u0103n c\u1ee9 n\u01b0\u1edbc ngo\u00e0i nh\u01b0 Vi\u1ec7t Nam, vi\u1ec7c x\u00e1c nh\u1eadn xem qu\u1ea3n l\u00fd ch\u1ea5t l\u01b0\u1ee3ng c\u00f3 \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n d\u1ef1a tr\u00ean JIS hay ISO thay v\u00ec c\u00e1c ti\u00eau chu\u1ea9n \u0111\u1ecba ph\u01b0\u01a1ng hay kh\u00f4ng l\u00e0 ch\u00eca kh\u00f3a \u0111\u1ec3 duy tr\u00ec “Ch\u1ea5t l\u01b0\u1ee3ng Nh\u1eadt B\u1ea3n”. T\u1ea1i Ohta Vi\u1ec7t Nam, ch\u00fang t\u00f4i ch\u1ec9 cung c\u1ea5p c\u00e1c s\u1ea3n ph\u1ea9m tu\u00e2n th\u1ee7 nghi\u00eam ng\u1eb7t c\u00e1c ti\u00eau chu\u1ea9n qu\u1ed1c t\u1ebf n\u00e0y, hi\u1ec7n th\u1ef1c h\u00f3a ch\u00ednh x\u00e1c \u00fd \u0111\u1ed3 thi\u1ebft k\u1ebf c\u1ee7a ph\u00eda Nh\u1eadt B\u1ea3n.<\/p>\n<\/div>\n

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Khoa h\u1ecdc thi\u1ebft k\u1ebf m\u1ed1i n\u1ed1i: C\u00f4ng th\u1ee9c t\u00ednh to\u00e1n v\u00e0 \u1ee9ng d\u1ee5ng IoT<\/h3>\n<\/div>\n
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T\u00ednh to\u00e1n m\u00f4-men xo\u1eafn si\u1ebft v\u00e0 thi\u1ebft k\u1ebf \u0111\u1ed9 b\u1ec1n<\/h4>\n<\/div>\n
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Trong vi\u1ec7c l\u1ef1a ch\u1ecdn v\u00edt, quan tr\u1ecdng nh\u1ea5t l\u00e0 ki\u1ec3m so\u00e1t “L\u1ef1c tr\u1ee5c” (L\u1ef1c si\u1ebft ch\u1eb7t). \u0110\u1ec3 th\u1ef1c hi\u1ec7n m\u1ed1i n\u1ed1i ph\u00f9 h\u1ee3p, c\u00f4ng th\u1ee9c c\u01a1 b\u1ea3n sau \u0111\u00e2y \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng:<\/p>\n<\/div>\n

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$$T = K \\cdot d \\cdot F$$<\/strong><\/p>\n<\/div>\n

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Trong \u0111\u00f3, $T$ l\u00e0 m\u00f4-men xo\u1eafn si\u1ebft (N\u00b7m), $K$ l\u00e0 h\u1ec7 s\u1ed1 m\u00f4-men xo\u1eafn, $d$ l\u00e0 \u0111\u01b0\u1eddng k\u00ednh danh ngh\u0129a c\u1ee7a v\u00edt (mm), v\u00e0 $F$ l\u00e0 l\u1ef1c tr\u1ee5c (N). V\u00ec h\u1ec7 s\u1ed1 m\u00f4-men xo\u1eafn $K$ thay \u0111\u1ed5i l\u1edbn t\u00f9y thu\u1ed9c v\u00e0o t\u00ecnh tr\u1ea1ng b\u00f4i tr\u01a1n b\u1ec1 m\u1eb7t v\u00edt v\u00e0 v\u1eadt li\u1ec7u, n\u00ean \u0111\u1ed1i v\u1edbi v\u00edt c\u00f3 c\u1ea5p b\u1ec1n c\u00e0ng cao, vi\u1ec7c qu\u1ea3n l\u00fd h\u1ec7 s\u1ed1 n\u00e0y c\u00e0ng tr\u1edf n\u00ean kh\u1eaft khe.<\/p>\n<\/div>\n

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\u201cS\u1ed1 h\u00f3a vi\u1ec7c l\u1eafp si\u1ebft\u201d b\u1eb1ng c\u00f4ng ngh\u1ec7 IoT<\/h4>\n<\/div>\n
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Trong nh\u1eefng n\u0103m g\u1ea7n \u0111\u00e2y, Ohta Vi\u1ec7t Nam \u0111ang ch\u00fa tr\u1ecdng v\u00e0o vi\u1ec7c x\u00e2y d\u1ef1ng nh\u00e0 m\u00e1y th\u00f4ng minh (Smart Factory) \u1ee9ng d\u1ee5ng IoT. Trong qu\u1ea3n l\u00fd ch\u1ea5t l\u01b0\u1ee3ng truy\u1ec1n th\u1ed1ng, vi\u1ec7c ki\u1ec3m tra m\u00f4-men xo\u1eafn b\u1eb1ng c\u00e1ch l\u1ea5y m\u1eabu l\u00e0 ch\u1ee7 y\u1ebfu, nh\u01b0ng b\u1eb1ng c\u00e1ch \u00e1p d\u1ee5ng c\u1edd l\u00ea l\u1ef1c k\u1ef9 thu\u1eadt s\u1ed1 h\u1ed7 tr\u1ee3 IoT, c\u00f3 th\u1ec3 thu th\u1eadp v\u00e0 ph\u00e2n t\u00edch d\u1eef li\u1ec7u c\u1ee7a t\u1ea5t c\u1ea3 c\u00e1c c\u00f4ng \u0111o\u1ea1n l\u1eafp si\u1ebft trong th\u1eddi gian th\u1ef1c.<\/p>\n<\/div>\n

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Nh\u1edd \u0111\u00f3, t\u00ednh truy xu\u1ea5t ngu\u1ed3n g\u1ed1c v\u1ec1 vi\u1ec7c “ai, khi n\u00e0o, si\u1ebft v\u1edbi l\u1ef1c bao nhi\u00eau” \u0111\u01b0\u1ee3c \u0111\u1ea3m b\u1ea3o, v\u00e0 c\u00f3 th\u1ec3 ch\u1ee9ng minh b\u1eb1ng k\u1ef9 thu\u1eadt s\u1ed1 r\u1eb1ng vi\u1ec7c l\u1eafp si\u1ebft t\u1ed1i \u01b0u d\u1ef1a tr\u00ean c\u1ea5p b\u1ec1n \u0111ang \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n. \u0110\u00e2y l\u00e0 m\u1ed9t l\u1ee3i th\u1ebf c\u1ea1nh tranh m\u1ea1nh m\u1ebd, \u0111\u1eb7c bi\u1ec7t trong c\u00e1c l\u0129nh v\u1ef1c y\u00eau c\u1ea7u \u0111\u1ed9 an to\u00e0n cao nh\u01b0 \u00f4 t\u00f4 hay thi\u1ebft b\u1ecb ch\u00ednh x\u00e1c.<\/p>\n<\/div>\n

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D\u1eef li\u1ec7u ch\u00ednh: Th\u1ed1ng k\u00ea v\u1ec1 th\u1ecb tr\u01b0\u1eddng v\u00edt, linh ki\u1ec7n l\u1eafp si\u1ebft v\u00e0 ch\u1ea5t l\u01b0\u1ee3ng<\/strong><\/p>\n

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