{"id":7481,"date":"2021-06-10T07:28:57","date_gmt":"2021-06-09T23:28:57","guid":{"rendered":"https:\/\/xzfastener.com\/?p=7481"},"modified":"2026-06-24T07:30:46","modified_gmt":"2026-06-23T23:30:46","slug":"fasteners-for-high-vibration-applications-anti-loosening-selection-guide","status":"publish","type":"post","link":"https:\/\/xzfastener.com\/vi\/fasteners-for-high-vibration-applications-anti-loosening-selection-guide\/","title":{"rendered":"Ch\u1ed1t cho c\u00e1c \u1ee9ng d\u1ee5ng c\u00f3 \u0111\u1ed9 rung cao: H\u01b0\u1edbng d\u1eabn l\u1ef1a ch\u1ecdn ch\u1ed1ng n\u1edbi l\u1ecfng"},"content":{"rendered":"

M\u00f4i tr\u01b0\u1eddng c\u00f3 \u0111\u1ed9 rung cao l\u00e0 m\u1ed9t trong nh\u1eefng \u0111i\u1ec1u ki\u1ec7n \u0111\u00f2i h\u1ecfi kh\u1eaft khe nh\u1ea5t \u0111\u1ed1i v\u1edbi hi\u1ec7u su\u1ea5t c\u1ee7a chi ti\u1ebft si\u1ebft ch\u1eb7t. Trong m\u00e1y m\u00f3c, h\u1ec7 th\u1ed1ng giao th\u00f4ng, thi\u1ebft b\u1ecb n\u0103ng l\u01b0\u1ee3ng v\u00e0 l\u1eafp \u0111\u1eb7t c\u00f4ng nghi\u1ec7p, rung \u0111\u1ed9ng th\u01b0\u1eddng kh\u00f4ng g\u00e2y ra h\u01b0 h\u1ecfng ngay l\u1eadp t\u1ee9c. Thay v\u00e0o \u0111\u00f3, n\u00f3 gi\u1ea3m d\u1ea7n t\u1ea3i tr\u01b0\u1edbc, d\u1eabn \u0111\u1ebfn l\u1ecfng l\u1ebbo, m\u1ecfi kh\u1edbp v\u00e0 cu\u1ed1i c\u00f9ng l\u00e0 h\u01b0 h\u1ecfng c\u1ea5u tr\u00fac ho\u1eb7c c\u01a1 h\u1ecdc.<\/p>\n\n\n\n

Trong th\u1ef1c t\u1ebf k\u1ef9 thu\u1eadt th\u1ef1c t\u1ebf, h\u1ea7u h\u1ebft c\u00e1c h\u01b0 h\u1ecfng li\u00ean quan \u0111\u1ebfn rung \u0111\u1ed9ng kh\u00f4ng ph\u1ea3i do \u0111\u1ed9 b\u1ec1n c\u1ee7a chi ti\u1ebft si\u1ebft ch\u1eb7t kh\u00f4ng \u0111\u1ee7 m\u00e0 do l\u1ef1a ch\u1ecdn kh\u00f4ng \u0111\u00fang ph\u01b0\u01a1ng ph\u00e1p ch\u1ed1ng n\u1edbi l\u1ecfng ho\u1eb7c ki\u1ec3m so\u00e1t l\u1eafp \u0111\u1eb7t k\u00e9m.<\/p>\n\n\n\n

\u0110\u1ed1i v\u1edbi c\u00e1c h\u1ec7 th\u1ed1ng bu\u1ed9c ch\u1eb7t ti\u00eau chu\u1ea9n v\u00e0 c\u01b0\u1eddng \u0111\u1ed9 cao \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong c\u00e1c \u1ee9ng d\u1ee5ng \u0111\u1ed9ng, ng\u01b0\u1eddi mua c\u00f3 th\u1ec3 xem x\u00e9t XZ Fastener's \u1ed1c v\u00edt c\u01b0\u1eddng \u0111\u1ed9 cao<\/a> v\u00e0 \u1ed1c v\u00edt ti\u00eau chu\u1ea9n<\/a> trang.<\/p>\n\n\n\n

1. T\u1ea1i sao rung \u0111\u1ed9ng l\u00e0m l\u1ecfng chi ti\u1ebft si\u1ebft ch\u1eb7t<\/h2>\n\n\n\n

Chuy\u1ec3n \u0111\u1ed9ng vi m\u00f4 l\u00e0 c\u01a1 ch\u1ebf th\u1ea5t b\u1ea1i th\u1ef1c s\u1ef1<\/h3>\n\n\n\n

Rung kh\u00f4ng tr\u1ef1c ti\u1ebfp \"th\u00e1o\" chi ti\u1ebft si\u1ebft ch\u1eb7t trong h\u1ea7u h\u1ebft c\u00e1c tr\u01b0\u1eddng h\u1ee3p. Thay v\u00e0o \u0111\u00f3, n\u00f3 g\u00e2y ra chuy\u1ec3n \u0111\u1ed9ng t\u01b0\u01a1ng \u0111\u1ed1i vi m\u00f4 gi\u1eefa c\u00e1c b\u1ec1 m\u1eb7t kh\u1edbp, l\u00e0m gi\u1ea3m d\u1ea7n t\u1ea3i tr\u01b0\u1edbc.<\/p>\n\n\n\n

nguy\u00ean nh\u00e2n<\/th>Hi\u1ec7u \u1ee9ng<\/th><\/tr><\/thead>
Vi tr\u01b0\u1ee3t gi\u1eefa c\u00e1c b\u1ec1 m\u1eb7t<\/td>M\u1ea5t kh\u1ea3 n\u0103ng ch\u1ed1ng ma s\u00e1t<\/td><\/tr>
T\u1ea3i tr\u01b0\u1edbc kh\u00f4ng \u0111\u1ee7<\/td>T\u00e1ch kh\u1edbp d\u01b0\u1edbi rung<\/td><\/tr>
Ph\u00e2n ph\u1ed1i t\u1ea3i kh\u00f4ng \u0111\u1ed3ng \u0111\u1ec1u<\/td>C\u0103ng th\u1eb3ng v\u00e0 chuy\u1ec3n \u0111\u1ed9ng c\u1ee5c b\u1ed9<\/td><\/tr>
nh\u00fang b\u1ec1 m\u1eb7t<\/td>S\u1ef1 th\u01b0 gi\u00e3n c\u1ee7a l\u1ef1c k\u1eb9p<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Sau khi gi\u1ea3m t\u1ea3i tr\u01b0\u1edbc, qu\u00e1 tr\u00ecnh n\u1edbi l\u1ecfng s\u1ebd t\u0103ng t\u1ed1c nhanh ch\u00f3ng.<\/p>\n\n\n\n

2. C\u00e1c lo\u1ea1i chi ti\u1ebft si\u1ebft ch\u1eb7t ch\u1ed1ng l\u1ecfng ch\u00ednh<\/h2>\n\n\n\n

C\u00e1c gi\u1ea3i ph\u00e1p kh\u00e1c nhau cho c\u00e1c m\u1ee9c \u0111\u1ed9 rung kh\u00e1c nhau<\/h3>\n\n\n\n
Lo\u1ea1i gi\u1ea3i ph\u00e1p<\/th>Mechanism<\/th>\u1ee8ng d\u1ee5ng<\/th><\/tr><\/thead>
\u0110ai \u1ed1c kh\u00f3a<\/td>Kh\u00e1ng c\u01a1 h\u1ecdc<\/td>M\u00e1y m\u00f3c t\u1ed5ng h\u1ee3p<\/td><\/tr>
\u0110ai \u1ed1c ch\u00e8n nylon<\/td>Kh\u00f3a ma s\u00e1t<\/td>H\u1ec7 th\u1ed1ng rung trung b\u00ecnh<\/td><\/tr>
V\u00f2ng \u0111\u1ec7m c\u00f3 r\u0103ng c\u01b0a<\/td>T\u0103ng \u0111\u1ed9 b\u00e1m b\u1ec1 m\u1eb7t<\/td>K\u1ebft c\u1ea5u th\u00e9p<\/td><\/tr>
V\u00f2ng \u0111\u1ec7m m\u00f9a xu\u00e2n<\/td>H\u1ed7 tr\u1ee3 t\u1ea3i tr\u01b0\u1edbc \u0111\u00e0n h\u1ed3i<\/td>\u0110i\u1ec1u ki\u1ec7n rung nh\u1eb9<\/td><\/tr>
\u0110ai \u1ed1c m\u00f4-men xo\u1eafn ph\u1ed5 bi\u1ebfn<\/td>Ki\u1ec3m so\u00e1t ma s\u00e1t<\/td>Thi\u1ebft b\u1ecb c\u00f4ng nghi\u1ec7p<\/td><\/tr>
L\u1edbp ph\u1ee7 kh\u00f3a ren<\/td>Li\u00ean k\u1ebft h\u00f3a h\u1ecdc ho\u1eb7c ma s\u00e1t<\/td>OEM t\u1eadp h\u1ee3p<\/td><\/tr>
H\u1ec7 th\u1ed1ng kh\u00f3a n\u00eam<\/td>H\u00e0nh \u0111\u1ed9ng n\u00eam c\u01a1 kh\u00ed<\/td>M\u00f4i tr\u01b0\u1eddng rung \u0111\u1ed9ng cao<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Kh\u00f4ng c\u00f3 gi\u1ea3i ph\u00e1p duy nh\u1ea5t n\u00e0o c\u00f3 t\u00e1c d\u1ee5ng cho m\u1ecdi \u0111i\u1ec1u ki\u1ec7n rung.<\/p>\n\n\n\n

3. Hi\u1ec3u m\u1ee9c \u0111\u1ed9 rung trong \u1ee9ng d\u1ee5ng<\/h2>\n\n\n\n

L\u1ef1a ch\u1ecdn ph\u1ea3i ph\u00f9 h\u1ee3p v\u1edbi \u0111i\u1ec1u ki\u1ec7n l\u00e0m vi\u1ec7c th\u1ef1c t\u1ebf<\/h3>\n\n\n\n

| M\u1ee9c \u0111\u1ed9 rung | \u1ee8ng d\u1ee5ng \u0111i\u1ec3n h\u00ecnh | M\u1ee9c \u0111\u1ed9 r\u1ee7i ro |
|—|—|
| \u0110\u1ed9 rung th\u1ea5p | M\u00e1y t\u0129nh \u0111i\u1ec7n | Th\u1ea5p |
| Rung \u0111\u1ed9ng trung b\u00ecnh | Thi\u1ebft b\u1ecb c\u00f4ng nghi\u1ec7p | Trung b\u00ecnh |
| \u0110\u1ed9 rung cao | \u0110\u1ed9ng c\u01a1, m\u00e1y b\u01a1m | Cao |
| Rung \u0111\u1ed9ng c\u1ef1c \u0111\u1ed9 | \u0110\u01b0\u1eddng s\u1eaft, tua bin gi\u00f3 | Quan tr\u1ecdng |<\/p>\n\n\n\n

Vi\u1ec7c l\u1ef1a ch\u1ecdn chi ti\u1ebft si\u1ebft ch\u1eb7t ph\u1ea3i d\u1ef1a tr\u00ean m\u00f4i tr\u01b0\u1eddng v\u1eadn h\u00e0nh th\u1ef1c t\u1ebf ch\u1ee9 kh\u00f4ng ph\u1ea3i ch\u1ec9 d\u1ef1a tr\u00ean t\u1ea3i tr\u1ecdng l\u00fd thuy\u1ebft.<\/p>\n\n\n\n

4. T\u1ea7m quan tr\u1ecdng c\u1ee7a t\u1ea3i tr\u01b0\u1edbc trong thi\u1ebft k\u1ebf ch\u1ed1ng n\u1edbi l\u1ecfng<\/h2>\n\n\n\n

T\u1ea3i tr\u01b0\u1edbc l\u00e0 bi\u1ec7n ph\u00e1p b\u1ea3o v\u1ec7 \u0111\u1ea7u ti\u00ean ch\u1ed1ng l\u1ea1i rung \u0111\u1ed9ng<\/h3>\n\n\n\n

Chi ti\u1ebft si\u1ebft ch\u1eb7t \u0111\u01b0\u1ee3c l\u1eafp \u0111\u1eb7t ch\u00ednh x\u00e1c d\u1ef1a v\u00e0o t\u1ea3i tr\u01b0\u1edbc \u0111\u1ec3 duy tr\u00ec t\u00ednh to\u00e0n v\u1eb9n c\u1ee7a kh\u1edbp. Thi\u1ebft b\u1ecb ch\u1ed1ng n\u1edbi l\u1ecfng l\u00e0 bi\u1ec7n ph\u00e1p b\u1ea3o v\u1ec7 th\u1ee9 c\u1ea5p.<\/p>\n\n\n\n

Y\u1ebfu t\u1ed1<\/th>Vai tr\u00f2 trong s\u1ef1 \u1ed5n \u0111\u1ecbnh chung<\/th><\/tr><\/thead>
T\u1ea3i tr\u01b0\u1edbc \u0111\u00fang<\/td>Kh\u1ea3 n\u0103ng ch\u1ed1ng n\u1edbi l\u1ecfng ch\u00ednh<\/td><\/tr>
Ki\u1ec3m so\u00e1t ma s\u00e1t<\/td>Duy tr\u00ec l\u1ef1c k\u1eb9p<\/td><\/tr>
T\u00ecnh tr\u1ea1ng b\u1ec1 m\u1eb7t<\/td>\u1ea2nh h\u01b0\u1edfng \u0111\u1ebfn t\u00ednh nh\u1ea5t qu\u00e1n c\u1ee7a t\u1ea3i tr\u01b0\u1edbc<\/td><\/tr>
\u0110\u1ed9 ch\u00ednh x\u00e1c c\u1ee7a m\u00f4-men xo\u1eafn<\/td>\u0110\u1ea3m b\u1ea3o si\u1ebft ch\u1eb7t ch\u00ednh x\u00e1c<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

\u0110\u1ed1i v\u1edbi c\u00e1c h\u1ec7 th\u1ed1ng c\u00f3 \u0111\u1ed9 b\u1ec1n cao, ng\u01b0\u1eddi mua c\u00f3 th\u1ec3 xem x\u00e9t XZ Fastener's \u1ed1c v\u00edt c\u01b0\u1eddng \u0111\u1ed9 cao<\/a>.<\/p>\n\n\n\n

5. Nh\u1eefng hi\u1ec3u l\u1ea7m th\u01b0\u1eddng g\u1eb7p trong l\u1ef1a ch\u1ecdn ch\u1ed1ng n\u1edbi l\u1ecfng<\/h2>\n\n\n\n

Ch\u1ec9 l\u1ef1a ch\u1ecdn s\u1ea3n ph\u1ea9m kh\u00f4ng gi\u1ea3i quy\u1ebft \u0111\u01b0\u1ee3c v\u1ea5n \u0111\u1ec1 rung \u0111\u1ed9ng<\/h3>\n\n\n\n
Misunderstanding<\/th>Th\u1ef1c t\u1ebf<\/th><\/tr><\/thead>
V\u00f2ng \u0111\u1ec7m kh\u00f3a ng\u0103n ch\u1eb7n t\u1ea5t c\u1ea3 s\u1ef1 l\u1ecfng l\u1ebbo<\/td>Ch\u1ec9 m\u1ed9t ph\u1ea7n c\u1ee7a gi\u1ea3i ph\u00e1p<\/td><\/tr>
M\u00f4-men xo\u1eafn cao h\u01a1n gi\u1ea3i quy\u1ebft c\u00e1c v\u1ea5n \u0111\u1ec1 rung \u0111\u1ed9ng<\/td>Si\u1ebft qu\u00e1 ch\u1eb7t c\u00f3 th\u1ec3 l\u00e0m h\u1ecfng kh\u1edbp<\/td><\/tr>
T\u1ea5t c\u1ea3 c\u00e1c \u0111ai \u1ed1c kh\u00f3a \u0111\u1ec1u ho\u1ea1t \u0111\u1ed9ng nh\u01b0 nhau<\/td>Hi\u1ec7u su\u1ea5t thay \u0111\u1ed5i t\u00f9y theo thi\u1ebft k\u1ebf<\/td><\/tr>
Ch\u1ea5t k\u1ebft d\u00ednh lo\u1ea1i b\u1ecf nhu c\u1ea7u xem x\u00e9t thi\u1ebft k\u1ebf<\/td>Thi\u1ebft k\u1ebf chung v\u1eabn c\u00f2n quan tr\u1ecdng<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Trong th\u1ef1c t\u1ebf, nhi\u1ec1u h\u01b0 h\u1ecfng x\u1ea3y ra do s\u1eed d\u1ee5ng c\u00e1c thi\u1ebft b\u1ecb ch\u1ed1ng n\u1edbi l\u1ecfng m\u00e0 kh\u00f4ng c\u00f3 s\u1ef1 ki\u1ec3m so\u00e1t t\u1ea3i tr\u01b0\u1edbc th\u00edch h\u1ee3p.<\/p>\n\n\n\n

6. \u1ea2nh h\u01b0\u1edfng c\u1ee7a v\u1eadt li\u1ec7u v\u00e0 l\u1edbp ph\u1ee7<\/h2>\n\n\n\n

\u0110i\u1ec1u ki\u1ec7n b\u1ec1 m\u1eb7t \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn h\u00e0nh vi ma s\u00e1t<\/h3>\n\n\n\n

Vi\u1ec7c l\u1ef1a ch\u1ecdn l\u1edbp ph\u1ee7 v\u00e0 v\u1eadt li\u1ec7u \u1ea3nh h\u01b0\u1edfng \u0111\u00e1ng k\u1ec3 \u0111\u1ebfn hi\u1ec7u su\u1ea5t ch\u1ed1ng n\u1edbi l\u1ecfng.<\/p>\n\n\n\n

Y\u1ebfu t\u1ed1<\/th>Hi\u1ec7u \u1ee9ng<\/th><\/tr><\/thead>
M\u1ea1 k\u1ebdm<\/td>Bi\u1ebfn \u0111\u1ed5i ma s\u00e1t v\u1eeba ph\u1ea3i<\/td><\/tr>
M\u1ea1 k\u1ebdm nh\u00fang n\u00f3ng<\/td>Ma s\u00e1t cao h\u01a1n, c\u1ea7n \u0111i\u1ec1u ch\u1ec9nh m\u00f4-men xo\u1eafn<\/td><\/tr>
PTFE l\u1edbp ph\u1ee7<\/td>Gi\u1ea3m ma s\u00e1t, \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn hi\u1ec7u su\u1ea5t kh\u00f3a<\/td><\/tr>
Th\u00e9p kh\u00f4ng g\u1ec9<\/td>Nguy c\u01a1 b\u1ecb d\u1ed3n n\u00e9n khi rung<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

\u0110\u1ed1i v\u1edbi h\u1ec7 th\u1ed1ng \u0111\u01b0\u1ee3c ph\u1ee7, ng\u01b0\u1eddi mua c\u00f3 th\u1ec3 xem l\u1ea1i XZ Fastener \u1ed1c v\u00edt tr\u00e1ng kh\u00e1c nhau<\/a> trang.<\/p>\n\n\n\n

7. Th\u1ef1c ti\u1ec5n t\u1ed1t nh\u1ea5t \u0111\u1ec3 l\u1ef1a ch\u1ecdn<\/h2>\n\n\n\n

B\u1eaft \u0111\u1ea7u t\u1eeb h\u00e0nh vi h\u1ec7 th\u1ed1ng, kh\u00f4ng ph\u1ea3i lo\u1ea1i s\u1ea3n ph\u1ea9m<\/h3>\n\n\n\n

Ph\u01b0\u01a1ng ph\u00e1p l\u1ef1a ch\u1ecdn c\u00f3 c\u1ea5u tr\u00fac c\u1ea3i thi\u1ec7n \u0111\u1ed9 tin c\u1eady:<\/p>\n\n\n\n

    \n
  1. X\u00e1c \u0111\u1ecbnh m\u1ee9c \u0111\u1ed9 v\u00e0 t\u1ea7n s\u1ed1 rung \u0111\u1ed9ng.<\/li>\n\n\n\n
  2. X\u00e1c \u0111\u1ecbnh lo\u1ea1i kh\u1edbp (t\u0129nh, \u0111\u1ed9ng, xoay).<\/li>\n\n\n\n
  3. X\u00e1c \u0111\u1ecbnh m\u1ee9c t\u1ea3i tr\u01b0\u1edbc y\u00eau c\u1ea7u.<\/li>\n\n\n\n
  4. Ch\u1ecdn c\u01a1 ch\u1ebf kh\u00f3a th\u00edch h\u1ee3p.<\/li>\n\n\n\n
  5. K\u1ebft h\u1ee3p v\u1eadt li\u1ec7u chi ti\u1ebft si\u1ebft ch\u1eb7t v\u00e0 h\u1ec7 th\u1ed1ng ph\u1ee7.<\/li>\n\n\n\n
  6. X\u00e1c nh\u1eadn m\u00f4-men xo\u1eafn v\u00e0 ph\u01b0\u01a1ng ph\u00e1p c\u00e0i \u0111\u1eb7t.<\/li>\n\n\n\n
  7. X\u00e1c nh\u1eadn y\u00eau c\u1ea7u b\u1ea3o tr\u00ec.<\/li>\n<\/ol>\n\n\n\n

    \u0110\u1ed1i v\u1edbi c\u00e1c h\u1ec7 th\u1ed1ng d\u1ef1a tr\u00ean v\u00f2ng \u0111\u1ec7m, ng\u01b0\u1eddi mua c\u0169ng c\u00f3 th\u1ec3 xem x\u00e9t XZ Fastener's v\u00f2ng \u0111\u1ec7m<\/a> trang.<\/p>\n\n\n\n

    8. \u1ee8ng d\u1ee5ng c\u00f4ng nghi\u1ec7p c\u1ee7a h\u1ec7 th\u1ed1ng ch\u1ed1ng n\u1edbi l\u1ecfng<\/h2>\n\n\n\n

    M\u00f4i tr\u01b0\u1eddng rung \u0111\u1ed9ng cao y\u00eau c\u1ea7u ki\u1ec3m so\u00e1t ch\u1eb7t ch\u1ebd<\/h3>\n\n\n\n
    Industry<\/th>\u1ee8ng d\u1ee5ng<\/th><\/tr><\/thead>
    \u00d4 t\u00f4<\/td>C\u1ee5m \u0111\u1ed9ng c\u01a1 v\u00e0 khung g\u1ea7m<\/td><\/tr>
    H\u1ec7 th\u1ed1ng \u0111\u01b0\u1eddng s\u1eaft<\/td>Kh\u1edbp rung t\u1ea7n s\u1ed1 cao<\/td><\/tr>
    N\u0103ng l\u01b0\u1ee3ng gi\u00f3<\/td>K\u1ebft n\u1ed1i c\u1ea5u tr\u00fac tuabin<\/td><\/tr>
    M\u00e1y b\u01a1m c\u00f4ng nghi\u1ec7p<\/td>H\u1ec7 th\u1ed1ng m\u00e1y quay<\/td><\/tr>
    Thi\u1ebft b\u1ecb x\u00e2y d\u1ef1ng<\/td>H\u1ec7 th\u1ed1ng t\u1ea3i \u0111\u1ed9ng n\u1eb7ng<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

    Trong nh\u1eefng m\u00f4i tr\u01b0\u1eddng n\u00e0y, \u0111\u1ed9 \u1ed5n \u0111\u1ecbnh c\u1ee7a kh\u1edbp \u1ea3nh h\u01b0\u1edfng tr\u1ef1c ti\u1ebfp \u0111\u1ebfn \u0111\u1ed9 an to\u00e0n v\u00e0 tu\u1ed5i th\u1ecd c\u1ee7a thi\u1ebft b\u1ecb.<\/p>\n\n\n\n

    9. RFQ Danh s\u00e1ch ki\u1ec3m tra d\u00e0nh cho ng\u01b0\u1eddi mua<\/h2>\n\n\n\n

    X\u00e1c \u0111\u1ecbnh r\u00f5 r\u00e0ng y\u00eau c\u1ea7u v\u1ec1 \u0111\u1ed9 rung tr\u01b0\u1edbc khi \u0111\u1eb7t h\u00e0ng<\/h3>\n\n\n\n

    M\u1ed9t RFQ ho\u00e0n ch\u1ec9nh n\u00ean bao g\u1ed3m:<\/p>\n\n\n\n