{"id":1589,"date":"2026-04-13T02:26:09","date_gmt":"2026-04-13T09:26:09","guid":{"rendered":"https:\/\/www.songhaiflanges.com\/?p=1589"},"modified":"2026-04-13T02:34:25","modified_gmt":"2026-04-13T09:34:25","slug":"flange-bolt-torque-values-complete-reference-guide-for-every-pressure-class","status":"publish","type":"post","link":"https:\/\/www.songhaiflanges.com\/ru\/flange-bolt-torque-values-complete-reference-guide-for-every-pressure-class\/","title":{"rendered":"Flange Bolt Torque Values: Complete Reference Guide for Every Pressure Class"},"content":{"rendered":"<h2>Introduction<\/h2>\n<p>Proper <strong>flange bolt torque<\/strong> is critical for maintaining leak-free joints in industrial piping systems. Incorrect torque values can lead to gasket failure, bolt damage, flange warping, and dangerous leaks.<\/p>\n<h2>Why Bolt Torque Matters<\/h2>\n<h3>Consequences of Improper Torque:<\/h3>\n<h4>Under-Torquing:<\/h4>\n<ul>\n<li>Insufficient gasket compression<\/li>\n<li>Joint leakage<\/li>\n<li>Gasket blowout<\/li>\n<li>Bolt loosening from vibration<\/li>\n<\/ul>\n<h4>Over-Torquing:<\/h4>\n<ul>\n<li>Bolt yielding or fracture<\/li>\n<li>Flange face damage<\/li>\n<li>Gasket crushing<\/li>\n<li>Thread stripping<\/li>\n<\/ul>\n<h2>Bolt Torque Fundamentals<\/h2>\n<h3>The Torque Formula:<\/h3>\n<p>T = K x D x P<\/p>\n<p>Where: T = Torque, K = Nut factor, D = Nominal bolt diameter, P = Desired bolt preload<\/p>\n<h2>ASME Pressure Class Torque Tables<\/h2>\n<h3>Class 150 Flange Bolt Torque Values<\/h3>\n<table>\n<tr>\n<th>Bolt Size<\/th>\n<th>ASTM A193 B7 (ft-lbs)<\/th>\n<th>ASTM A193 B7 (Nm)<\/th>\n<\/tr>\n<tr>\n<td>M12<\/td>\n<td>45<\/td>\n<td>61<\/td>\n<\/tr>\n<tr>\n<td>M16<\/td>\n<td>95<\/td>\n<td>129<\/td>\n<\/tr>\n<tr>\n<td>M20<\/td>\n<td>185<\/td>\n<td>251<\/td>\n<\/tr>\n<tr>\n<td>M24<\/td>\n<td>310<\/td>\n<td>420<\/td>\n<\/tr>\n<tr>\n<td>M30<\/td>\n<td>600<\/td>\n<td>814<\/td>\n<\/tr>\n<tr>\n<td>M36<\/td>\n<td>950<\/td>\n<td>1288<\/td>\n<\/tr>\n<\/table>\n<h3>Class 300 Flange Bolt Torque Values<\/h3>\n<table>\n<tr>\n<th>Bolt Size<\/th>\n<th>ASTM A193 B7 (ft-lbs)<\/th>\n<th>ASTM A193 B7 (Nm)<\/th>\n<\/tr>\n<tr>\n<td>M20<\/td>\n<td>220<\/td>\n<td>298<\/td>\n<\/tr>\n<tr>\n<td>M24<\/td>\n<td>370<\/td>\n<td>502<\/td>\n<\/tr>\n<tr>\n<td>M30<\/td>\n<td>720<\/td>\n<td>976<\/td>\n<\/tr>\n<tr>\n<td>M36<\/td>\n<td>1200<\/td>\n<td>1627<\/td>\n<\/tr>\n<tr>\n<td>M42<\/td>\n<td>1850<\/td>\n<td>2508<\/td>\n<\/tr>\n<\/table>\n<h2>Bolt Material Specifications<\/h2>\n<h3>ASTM A193 B7:<\/h3>\n<ul>\n<li>Chromium-molybdenum steel<\/li>\n<li>Temperature range: -50F to 1000F<\/li>\n<li>Most common for carbon steel flanges<\/li>\n<\/ul>\n<h3>ASTM A193 B8M:<\/h3>\n<ul>\n<li>316 stainless steel<\/li>\n<li>Excellent corrosion resistance<\/li>\n<li>Temperature range: -425F to 1000F<\/li>\n<\/ul>\n<h2>Bolt Torquing Procedures<\/h2>\n<h3>Step-by-Step Torquing Sequence:<\/h3>\n<ol>\n<li><strong>Preparation<\/strong> &#8211; Clean all threads and mating surfaces<\/li>\n<li><strong>Hand Tightening<\/strong> &#8211; Install all bolts finger-tight<\/li>\n<li><strong>Initial Torque (30%)<\/strong> &#8211; Use star\/cross pattern<\/li>\n<li><strong>Intermediate Torque (60%)<\/strong> &#8211; Follow same star pattern<\/li>\n<li><strong>Final Torque (100%)<\/strong> &#8211; Complete star pattern<\/li>\n<li><strong>Verification Pass<\/strong> &#8211; Recheck all bolts<\/li>\n<\/ol>\n<h2>Conclusion<\/h2>\n<p>Proper flange bolt torquing ensures safe, leak-free piping systems. Following established procedures and using calibrated equipment is essential.<\/p>\n<p><strong>Songhai Flanges<\/strong> provides technical support for flange assembly, bolt selection, and torque specifications.<\/p>\n<p><strong>WhatsApp:<\/strong>\u00a0+86-18658777855<br \/>\n<strong>Email:<\/strong>\u00a01007788887@qq.com<br \/>\n<a href=\"https:\/\/www.720yun.com\/vr\/a6ajt7ynrw0\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-1480\" src=\"http:\/\/www.songhaiflanges.com\/wp-content\/uploads\/2026\/04\/4-1.webp\" alt=\"\" width=\"1290\" height=\"2317\" srcset=\"https:\/\/www.songhaiflanges.com\/wp-content\/uploads\/2026\/04\/4-1.webp 1290w, https:\/\/www.songhaiflanges.com\/wp-content\/uploads\/2026\/04\/4-1-167x300.webp 167w, https:\/\/www.songhaiflanges.com\/wp-content\/uploads\/2026\/04\/4-1-570x1024.webp 570w, https:\/\/www.songhaiflanges.com\/wp-content\/uploads\/2026\/04\/4-1-768x1379.webp 768w, https:\/\/www.songhaiflanges.com\/wp-content\/uploads\/2026\/04\/4-1-855x1536.webp 855w, https:\/\/www.songhaiflanges.com\/wp-content\/uploads\/2026\/04\/4-1-1140x2048.webp 1140w, https:\/\/www.songhaiflanges.com\/wp-content\/uploads\/2026\/04\/4-1-7x12.webp 7w\" sizes=\"auto, (max-width: 1290px) 100vw, 1290px\" \/><\/a><\/p>","protected":false},"excerpt":{"rendered":"<p>Complete flange bolt torque reference guide with tables for all ASME pressure classes. Learn proper torquing procedures, bolt materials, and best practices.<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_kadence_starter_templates_imported_post":false,"_kad_post_transparent":"default","_kad_post_title":"default","_kad_post_layout":"default","_kad_post_sidebar_id":"","_kad_post_content_style":"default","_kad_post_vertical_padding":"default","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"footnotes":""},"categories":[1],"tags":[179,193,191,195,189,194,192,190],"class_list":["post-1589","post","type-post","status-publish","format-standard","hentry","category-3-news","tag-asme-flanges","tag-astm-a193","tag-bolt-specifications","tag-bolt-tightening-sequence","tag-flange-bolt-torque","tag-pipe-flange-assembly","tag-torque-procedure","tag-torque-values"],"_links":{"self":[{"href":"https:\/\/www.songhaiflanges.com\/ru\/wp-json\/wp\/v2\/posts\/1589","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.songhaiflanges.com\/ru\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.songhaiflanges.com\/ru\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.songhaiflanges.com\/ru\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.songhaiflanges.com\/ru\/wp-json\/wp\/v2\/comments?post=1589"}],"version-history":[{"count":3,"href":"https:\/\/www.songhaiflanges.com\/ru\/wp-json\/wp\/v2\/posts\/1589\/revisions"}],"predecessor-version":[{"id":1600,"href":"https:\/\/www.songhaiflanges.com\/ru\/wp-json\/wp\/v2\/posts\/1589\/revisions\/1600"}],"wp:attachment":[{"href":"https:\/\/www.songhaiflanges.com\/ru\/wp-json\/wp\/v2\/media?parent=1589"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.songhaiflanges.com\/ru\/wp-json\/wp\/v2\/categories?post=1589"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.songhaiflanges.com\/ru\/wp-json\/wp\/v2\/tags?post=1589"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}