{"id":8782,"date":"2021-02-11T21:30:24","date_gmt":"2021-02-11T13:30:24","guid":{"rendered":"https:\/\/xzfastener.com\/?p=8782"},"modified":"2026-06-29T21:32:23","modified_gmt":"2026-06-29T13:32:23","slug":"bolt-diameter-guide-nominal-size-shank-size-and-thread-size","status":"publish","type":"post","link":"https:\/\/xzfastener.com\/vi\/bolt-diameter-guide-nominal-size-shank-size-and-thread-size\/","title":{"rendered":"H\u01b0\u1edbng d\u1eabn v\u1ec1 \u0111\u01b0\u1eddng k\u00ednh bu l\u00f4ng: K\u00edch th\u01b0\u1edbc danh ngh\u0129a, K\u00edch th\u01b0\u1edbc th\u00e2n v\u00e0 K\u00edch th\u01b0\u1edbc ren"},"content":{"rendered":"<p>Bolt diameter looks simple until an RFQ, drawing, and actual part do not match. A buyer may write \u201cM12 bolt,\u201d but the supplier still needs to know the standard, thread pitch, shank style, tolerance, and whether the bolt is fully threaded or partially threaded.<\/p>\n\n\n\n<p>For industrial purchasing, diameter is not one number. It is a set of related dimensions.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">The Three Diameter Terms Buyers Should Know<\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>k\u1ef3 h\u1ea1n<\/th><th>\u00dd ngh\u0129a<\/th><th>T\u1ea1i sao n\u00f3 quan tr\u1ecdng<\/th><\/tr><\/thead><tbody><tr><td>K\u00edch th\u01b0\u1edbc danh ngh\u0129a<\/td><td>The named bolt size, such as M12 or 1\/2 inch<\/td><td>Used for RFQs, catalogs, and standard selection<\/td><\/tr><tr><td>Shank size<\/td><td>The unthreaded body diameter under the head<\/td><td>Affects fit through holes and shear area<\/td><\/tr><tr><td>K\u00edch th\u01b0\u1edbc ch\u1ee7 \u0111\u1ec1<\/td><td>The thread diameter and pitch, such as M12 x 1.75 or 1\/2-13 UNC<\/td><td>Controls nut fit, thread engagement, and compatibility<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p>\u0110\u1ed1i v\u1edbi c\u00e1c m\u1eb7t h\u00e0ng th\u00f4ng th\u01b0\u1eddng trong danh m\u1ee5c, ng\u01b0\u1eddi mua c\u00f3 th\u1ec3 xem l\u1ea1i <a href=\"https:\/\/xzfastener.com\/vi\/products-category\/standard-fasteners\/\">\u1ed1c v\u00edt ti\u00eau chu\u1ea9n<\/a> v\u00e0 x\u00e1c nh\u1eadn ti\u00eau chu\u1ea9n ch\u00ednh x\u00e1c tr\u01b0\u1edbc khi \u0111\u1eb7t h\u00e0ng.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Nominal Diameter Is a Name, Not Always the Measured Value<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Metric Bolts<\/h3>\n\n\n\n<p>For metric bolts, \u201cM12\u201d means the nominal thread diameter is 12 mm. The actual outside diameter of the thread is usually slightly below 12 mm because of manufacturing tolerances.<\/p>\n\n\n\n<p>A typical metric callout may be:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>M12 x 1.75 x 60 mm<\/li>\n\n\n\n<li>M12 = nominal thread diameter<\/li>\n\n\n\n<li>1.75 = thread pitch in millimeters<\/li>\n\n\n\n<li>60 mm = bolt length<\/li>\n<\/ul>\n\n\n\n<p>For metric standard comparison, this <a href=\"https:\/\/xzfastener.com\/vi\/din-iso-fastener-standards-complete-overview-for-industrial-buyers\/\">H\u01b0\u1edbng d\u1eabn ti\u00eau chu\u1ea9n chi ti\u1ebft si\u1ebft ch\u1eb7t DIN v\u00e0 ISO<\/a> helps buyers avoid confusing similar standards.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Inch Bolts<\/h3>\n\n\n\n<p>For inch fasteners, a size such as 1\/2-13 UNC means:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>1\/2 inch = nominal diameter<\/li>\n\n\n\n<li>13 = threads per inch<\/li>\n\n\n\n<li>UNC = Unified coarse thread<\/li>\n<\/ul>\n\n\n\n<p>UNF threads use more threads per inch and are not interchangeable with UNC.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Shank Diameter and Hole Fit<\/h2>\n\n\n\n<p>The shank is the unthreaded portion of a partially threaded bolt. It may be close to the nominal diameter, but the exact tolerance depends on the standard and product type.<\/p>\n\n\n\n<p>Shank size matters when:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The bolt passes through precision holes.<\/li>\n\n\n\n<li>The joint carries shear load.<\/li>\n\n\n\n<li>The assembly needs alignment.<\/li>\n\n\n\n<li>The drawing requires a shoulder or close body fit.<\/li>\n<\/ul>\n\n\n\n<p>Do not assume a fully threaded bolt and a partially threaded bolt will behave the same in a shear joint.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Thread Diameter and Pitch<\/h2>\n\n\n\n<p>Thread size controls assembly with nuts or tapped holes. A bolt with the correct nominal diameter but wrong pitch will not fit.<\/p>\n\n\n\n<p>Ng\u01b0\u1eddi mua n\u00ean x\u00e1c nh\u1eadn:<\/p>\n\n\n\n<ol start=\"1\" class=\"wp-block-list\">\n<li>Ren h\u1ec7 m\u00e9t ho\u1eb7c inch.<\/li>\n\n\n\n<li>Coarse or fine pitch.<\/li>\n\n\n\n<li>Ren to\u00e0n b\u1ed9 ho\u1eb7c ch\u1ee7 \u0111\u1ec1 m\u1ed9t ph\u1ea7n.<\/li>\n\n\n\n<li>Thread tolerance class.<\/li>\n\n\n\n<li>Matching nut standard.<\/li>\n\n\n\n<li>Coating effect on thread fit.<\/li>\n<\/ol>\n\n\n\n<p>For coated parts, confirm thread fit after finishing, especially for hot-dip galvanized fasteners.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">RFQ Danh s\u00e1ch ki\u1ec3m tra<\/h2>\n\n\n\n<p>Tr\u01b0\u1edbc khi y\u00eau c\u1ea7u b\u00e1o gi\u00e1, h\u00e3y cung c\u1ea5p:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Standard or drawing.<\/li>\n\n\n\n<li>Nominal size.<\/li>\n\n\n\n<li>Length.<\/li>\n\n\n\n<li>Thread pitch.<\/li>\n\n\n\n<li>Ren to\u00e0n b\u1ed9 ho\u1eb7c ch\u1ee7 \u0111\u1ec1 m\u1ed9t ph\u1ea7n.<\/li>\n\n\n\n<li>Shank requirement.<\/li>\n\n\n\n<li>Grade and material.<\/li>\n\n\n\n<li>Finish.<\/li>\n\n\n\n<li>Quantity and inspection needs.<\/li>\n<\/ul>\n\n\n\n<p>For mixed bolt, nut, and washer orders, buyers can <a href=\"https:\/\/xzfastener.com\/vi\/home\/contact-us\/\">li\u00ean h\u1ec7 XZ Fastener<\/a> with drawings or size lists to reduce diameter and thread specification errors.<\/p>","protected":false},"excerpt":{"rendered":"<p>Bolt diameter looks simple until an RFQ, drawing, and actual part do not match. A buyer may write \u201cM12 bolt,\u201d but the supplier still needs to know the standard, thread pitch, shank style, tolerance, and whether the bolt is fully threaded or partially threaded. For industrial purchasing, diameter is not one number. It is a [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[479],"tags":[482],"class_list":["post-8782","post","type-post","status-publish","format-standard","hentry","category-fastener-knowledge-library","tag-fastener-sizes-specifications"],"acf":[],"_links":{"self":[{"href":"https:\/\/xzfastener.com\/vi\/wp-json\/wp\/v2\/posts\/8782","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/xzfastener.com\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/xzfastener.com\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/xzfastener.com\/vi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/xzfastener.com\/vi\/wp-json\/wp\/v2\/comments?post=8782"}],"version-history":[{"count":1,"href":"https:\/\/xzfastener.com\/vi\/wp-json\/wp\/v2\/posts\/8782\/revisions"}],"predecessor-version":[{"id":8783,"href":"https:\/\/xzfastener.com\/vi\/wp-json\/wp\/v2\/posts\/8782\/revisions\/8783"}],"wp:attachment":[{"href":"https:\/\/xzfastener.com\/vi\/wp-json\/wp\/v2\/media?parent=8782"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/xzfastener.com\/vi\/wp-json\/wp\/v2\/categories?post=8782"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/xzfastener.com\/vi\/wp-json\/wp\/v2\/tags?post=8782"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}