{"id":5467,"date":"2023-11-30T04:09:35","date_gmt":"2023-11-30T04:09:35","guid":{"rendered":"https:\/\/masterskills.org\/blog\/?p=5467"},"modified":"2023-11-29T18:34:58","modified_gmt":"2023-11-29T18:34:58","slug":"six-sigma-lech-chuan-va-su-bien-dong","status":"publish","type":"post","link":"https:\/\/masterskills.org\/blog\/six-sigma-lech-chuan-va-su-bien-dong.html","title":{"rendered":"SIX SIGMA \u2013 \u0110\u1ed8 L\u1ec6CH CHU\u1ea8N V\u00c0 S\u1ef0 BI\u1ebeN \u0110\u1ed8NG"},"content":{"rendered":"

\u201cSigma\u201d trong b\u1ea3ng th\u1ee9 t\u1ef1 alphabet – l\u00e0 m\u1ed9t k\u00fd hi\u1ec7u s\u1eed d\u1ee5ng trong k\u1ef9 thu\u1eadt th\u1ed1ng k\u00ea \u0111\u1ec3 ch\u1ec9 \u201c\u0111\u1ed9 l\u1ec7ch chu\u1ea9n\u201d c\u1ee7a m\u1ed9t t\u1eadp h\u1ee3p. \u0110\u1ed9 l\u1ec7ch chu\u1ea9n cho bi\u1ebft \u201cs\u1ef1 bi\u1ebfn \u0111\u1ed9ng\u201d hay \u201cs\u1ef1 sai l\u1ec7ch\u201d c\u1ee7a m\u1ed9t ho\u1ea1t \u0111\u1ed9ng ho\u1eb7c qu\u00e1 tr\u00ecnh hay s\u1ea3n ph\u1ea9m. Th\u00f4ng th\u01b0\u1eddng, s\u1ef1 bi\u1ebfn \u0111\u1ed9ng hay s\u1ef1 sai l\u1ec7ch \u0111\u01b0\u1ee3c t\u00ednh quanh gi\u00e1 tr\u1ecb trung b\u00ecnh.<\/p>\n

V\u00ed d\u1ee5, trong qu\u00e1 tr\u00ecnh s\u1ea3n xu\u1ea5t, \u0111\u1ed9 d\u00e0i s\u1ea3n ph\u1ea9m d\u00e2y \u0111i\u1ec7n sau khi c\u1eaft l\u00e0 50 +- 2.5mm. S\u1ea3n ph\u1ea9m sau khi c\u1eaft, c\u00f3 th\u1ec3 s\u1ebd l\u00e0 50,1; 49.0\u2026 v\u00e0 ch\u1eafc ch\u1eafc s\u1ebd lu\u00f4n c\u00f3 s\u1ef1 sai l\u1ec7ch.\u00a0Kh\u00f4ng c\u00f3 c\u00f4ng \u0111o\u1ea1n s\u1ea3n xu\u1ea5t n\u00e0o t\u1ea1o ra 100% s\u1ea3n ph\u1ea9m gi\u1ed1ng h\u1ec7t nhau m\u00e0 kh\u00f4ng c\u00f3 sai l\u1ec7ch<\/strong>. \u0110\u00e2y l\u00e0 nguy\u00ean t\u1eafc c\u01a1 b\u1ea3n v\u00e0 quan tr\u1ecdng nh\u1ea5t c\u1ee7a s\u1ea3n xu\u1ea5t. S\u1ef1 sai l\u1ec7ch n\u00e0y \u0111\u01b0\u1ee3c \u0111\u1ecbnh ngh\u0129a th\u00f4ng qua gi\u00e1 tr\u1ecb \u201csigma\u201d.<\/em><\/p>\n

V\u00e0 ph\u01b0\u01a1ng ph\u00e1p 6 sigma l\u00e0 c\u00e1ch ti\u1ebfp c\u1eadn \u0111\u1ec3 nh\u1eadn d\u1ea1ng v\u00e0 lo\u1ea1i tr\u1eeb c\u00e1c bi\u1ebfn \u0111\u1ed9ng (Sai l\u1ec7ch) trong c\u00f4ng \u0111o\u1ea1n. Gi\u00fap s\u1ea3n ph\u1ea9m \u0111\u1ea7u ra \u0111\u1ea1t \u0111\u01b0\u1ee3c ch\u00ednh x\u00e1c nh\u1eefng y\u00eau c\u1ea7u ti\u00eau chu\u1ea9n hay y\u00eau c\u1ea7u c\u1ee7a kh\u00e1ch h\u00e0ng.<\/p>\n

DPMO \u2013 Defects Per Million Opportunities<\/strong><\/p>\n

\u0110i\u1ec1u c\u0103n b\u1ea3n \u0111\u1ea7u ti\u00ean khi \u00e1p d\u1ee5ng 6 Sigma l\u00e0 l\u00e0m r\u00f5 nh\u1eefng g\u00ec ti\u00eau chu\u1ea9n (Hay kh\u00e1ch h\u00e0ng mu\u1ed1n) \u0111\u1ec3 chuy\u1ec3n th\u00e0nh c\u00e1c y\u00eau c\u1ea7u r\u00f5 r\u00e0ng. C\u00e1c y\u00eau c\u1ea7u n\u00e0y \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 \u201cCTQs – Critical to Quality\u201d (c\u00e1c \u0111\u1eb7c t\u00ednh quan tr\u1ecdng v\u1ec1 ch\u1ea5t l\u01b0\u1ee3ng). Trong s\u1ea3n xu\u1ea5t, m\u1ee5c ti\u00eau cao nh\u1ea5t khi \u00e1p d\u1ee5ng 6 sigma l\u00e0 h\u01b0\u1edbng t\u1edbi m\u1ed9t process kh\u00f4ng t\u1ea1o ra l\u1ed7i (Zero Defects). \u0110\u00e2y l\u00e0 \u0111i\u1ec1u ki\u1ec7n l\u00fd t\u01b0\u1edfng nh\u1ea5t trong s\u1ea3n xu\u1ea5t.<\/p>\n

M\u1ee9c sigma d\u00f9ng \u0111\u1ec3 ch\u1ec9 s\u1ed1 l\u1ed7i (Defects) x\u1ea3y ra tr\u00ean m\u1ed9t tri\u1ec7u c\u01a1 h\u1ed9i (DPMO – Defects Per Million Opportunities). Ch\u1ec9 s\u1ed1 DPMO \u0111\u01b0\u1ee3c t\u00ednh theo c\u00f4ng th\u1ee9c sau:<\/p>\n

DPMO = (s\u1ed1 l\u1ed7i x 1.000.000) \/ S\u1ed1 c\u01a1 h\u1ed9i x\u1ea3y ra l\u1ed7i<\/strong><\/p>\n

V\u00ed d\u1ee5: s\u1ea3n l\u01b0\u1ee3ng 1 ng\u00e0y c\u1ee7a chuy\u1ec1n A l\u00e0 1600 pcs, trong \u0111\u00f3 s\u1ed1 l\u01b0\u1ee3ng con h\u00e0ng b\u1ecb l\u1ed7i l\u00e0 50 pcs. V\u00e0 s\u1ed1 c\u01a1 h\u1ed9i (theo l\u00fd thuy\u1ebft) c\u00f3 th\u1ec3 t\u1ea1o ra l\u1ed7i tr\u00ean chuy\u1ec1n l\u00e0 10. Nh\u01b0 v\u1eady ch\u1ec9 s\u1ed1 DPMO s\u1ebd \u0111\u01b0\u1ee3c t\u00ednh nh\u01b0 sau:<\/em><\/p>\n

DPMO = (50 x 1.000.000) \/ (1600 x 10) = 3125<\/strong><\/em><\/p>\n

Theo b\u1ea3ng chuy\u1ec3n \u0111\u1ed5i, m\u1ee9c sigma t\u01b0\u01a1ng \u1ee9ng v\u1edbi ch\u1ec9 s\u1ed1 DPMO n\u00e0y s\u1ebd l\u00e0 4,2. T\u01b0\u01a1ng \u1ee9ng v\u1edbi t\u1ec9 l\u1ec7 \u0111\u1ea1t c\u1ee7a s\u1ea3n ph\u1ea9m l\u00e0 99,7%.<\/em><\/p>\n

\u0110\u1ec3 t\u00ednh \u0111\u01b0\u1ee3c ch\u00ednh x\u00e1c m\u1ee9c sigma c\u1ee7a m\u1ed9t qu\u00e1 tr\u00ecnh (process), ch\u00fang ta c\u1ea7n xem x\u00e9t t\u1ed5ng h\u1ee3p t\u1ea5t c\u1ea3 c\u00e1c b\u01b0\u1edbc trong qu\u00e1 tr\u00ecnh \u0111\u00f3: s\u01a1 \u0111\u1ed3 qu\u00e1 tr\u00ecnh, \u0111\u1eb7c t\u00ednh ch\u1ea5t l\u01b0\u1ee3ng s\u1ea3n ph\u1ea9m, c\u00e1c c\u01a1 h\u1ed9i t\u1ea1o ra s\u1ea3n ph\u1ea9m l\u1ed7i c\u0103n c\u1ee9 v\u00e0o ti\u00eau chu\u1ea9n \u0111\u00e3 \u0111\u1ec1 ra…<\/p>\n

V\u00ed d\u1ee5: T\u00ednh DPMO c\u1ee7a m\u1ed9t process theo th\u00f4ng tin b\u00ean d\u01b0\u1edbi:<\/em><\/p>\n\n\n\n\n\n\n\n\n\n\n
<\/td>\nC\u00f4ng \u0111o\u1ea1n 1<\/strong><\/td>\nC\u00f4ng \u0111o\u1ea1n 2<\/strong><\/td>\nC\u00f4ng \u0111o\u1ea1n 3<\/strong><\/td>\nC\u00f4ng \u0111o\u1ea1n 4<\/strong><\/td>\n<\/tr>\n
S\u1ed1 c\u01a1 h\u1ed9i x\u1ea3y ra l\u1ed7i<\/strong><\/td>\n11<\/td>\n9<\/td>\n5<\/td>\n7<\/td>\n<\/tr>\n
S\u1ed1 l\u1ed7i<\/strong><\/td>\n45<\/td>\n57<\/td>\n96<\/td>\n125<\/td>\n<\/tr>\n
S\u1ed1 s\u1ea3n ph\u1ea9m<\/strong><\/td>\n100<\/td>\n<\/tr>\n
S\u1ed1 l\u1ed7i<\/strong><\/td>\n323<\/td>\n<\/tr>\n
T\u1ed5ng s\u1ed1 c\u01a1 h\u1ed9i<\/strong><\/td>\n32<\/td>\n<\/tr>\n
DPMO<\/strong><\/td>\n(323 x 1.000.000)\/( 100 x 32) = 100.937<\/td>\n<\/tr>\n
Sigma x\u1ea5p x\u1ec9<\/strong><\/td>\n2,8<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 <\/p>\n

SIGMA V\u00c0 QUAN H\u1ec6 GI\u1eeeA K\u1ebeT QU\u1ea2 V\u00c0 C\u00c1C Y\u1ebeU T\u1ed0 H\u1ec6 TH\u1ed0NG<\/strong><\/p>\n

L\u01b0u \u0111\u1ed3 b\u00ean d\u01b0\u1edbi l\u00e0 v\u00ed d\u1ee5 minh h\u1ecda m\u00f4 t\u1ea3 m\u1ed9t\u00a0qu\u00e1 tr\u00ecnh s\u1ea3n xu\u1ea5t.<\/p>\n

M\u1ed1i quan h\u1ec7 gi\u1eefa \u0110\u1ea7u ra (output) v\u00e0 \u0111\u1ea7u v\u00e0o (INPUT) c\u00f3 th\u1ec3 m\u00f4 t\u1ea3 b\u1eb1ng h\u00e0m sau:<\/p>\n

Y = f(X) = f(X1; X2\u2026Xn)<\/strong><\/p>\n

Nh\u01b0 v\u1eady, m\u1ed9t ng\u01b0\u1eddi k\u1ef9 s\u01b0 mu\u1ed1n ki\u1ec3m so\u00e1t t\u1ed1t process (hay ki\u1ec3m so\u00e1t \u0111\u1ea7u ra OUTPUT Y) c\u1ea7n ph\u1ea3i t\u00ednh to\u00e1n nh\u1eefng t\u00e1c \u0111\u1ed9ng c\u1ee7a s\u1ef1 thay \u0111\u1ed5i c\u1ee7a X t\u1edbi Y v\u00e0 x\u00e1c \u0111\u1ecbnh xem s\u1ef1 bi\u1ebfn \u0111\u1ed9ng c\u1ee7a X s\u1ebd \u1ea3nh h\u01b0\u1edfng nh\u01b0 th\u1ebf n\u00e0o \u0111\u1ebfn Y.<\/p>\n

Trong qu\u00e1 tr\u00ecnh s\u1ea3n xu\u1ea5t, s\u1ef1 bi\u1ebfn \u0111\u1ed9ng c\u1ee7a X th\u00f4ng th\u01b0\u1eddng bao g\u1ed3m s\u1ef1 bi\u1ebfn \u0111\u1ed9ng c\u1ee7a:<\/p>\n

    \n
  1. Nguy\u00ean v\u1eadt li\u1ec7u (Material)<\/li>\n
  2. Con ng\u01b0\u1eddi (Man)<\/li>\n
  3. Thi\u1ebft b\u1ecb (Machine)<\/li>\n
  4. \u0110o l\u01b0\u1eddng (Measurement)<\/li>\n
  5. Ph\u01b0\u01a1ng ph\u00e1p (Method)<\/li>\n
  6. M\u00f4i tr\u01b0\u1eddng (Environment).<\/li>\n<\/ol>\n

    B\u1eb1ng vi\u1ec7c s\u1eed d\u1ee5ng ph\u01b0\u01a1ng ph\u00e1p 6 Sigma \u0111\u1ec3 hi\u1ec3u r\u00f5 h\u1ec7 th\u1ed1ng v\u00e0 c\u00e1c bi\u1ebfn s\u1ed1 c\u1ee7a h\u1ec7 th\u1ed1ng, ng\u01b0\u1eddi k\u1ef9 s\u01b0 c\u00f3 th\u1ec3 ki\u1ec3m so\u00e1t v\u00e0 t\u00e1c \u0111\u1ed9ng t\u1edbi c\u00e1c y\u1ebfu t\u1ed1 tr\u00ean con \u0111\u01b0\u1eddng ti\u1ebfn t\u1edbi m\u1ee5c ti\u00eau, khi\u1ebfn cho m\u1ee5c ti\u00eau c\u00f3 th\u1ec3 \u0111\u1ea1t \u0111\u01b0\u1ee3c nhanh h\u01a1n.<\/p>\n","protected":false},"excerpt":{"rendered":"

    \u201cSigma\u201d trong b\u1ea3ng th\u1ee9 t\u1ef1 alphabet – l\u00e0 m\u1ed9t k\u00fd hi\u1ec7u s\u1eed d\u1ee5ng trong k\u1ef9 thu\u1eadt th\u1ed1ng k\u00ea \u0111\u1ec3 ch\u1ec9 \u201c\u0111\u1ed9 l\u1ec7ch chu\u1ea9n\u201d c\u1ee7a m\u1ed9t t\u1eadp h\u1ee3p. \u0110\u1ed9 l\u1ec7ch chu\u1ea9n cho bi\u1ebft \u201cs\u1ef1 bi\u1ebfn \u0111\u1ed9ng\u201d hay \u201cs\u1ef1 sai l\u1ec7ch\u201d c\u1ee7a m\u1ed9t ho\u1ea1t \u0111\u1ed9ng ho\u1eb7c qu\u00e1 tr\u00ecnh hay s\u1ea3n ph\u1ea9m. Th\u00f4ng th\u01b0\u1eddng, s\u1ef1 bi\u1ebfn \u0111\u1ed9ng hay […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[220,229],"tags":[],"_links":{"self":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/posts\/5467"}],"collection":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/comments?post=5467"}],"version-history":[{"count":0,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/posts\/5467\/revisions"}],"wp:attachment":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/media?parent=5467"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/categories?post=5467"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/tags?post=5467"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}