{"id":1554,"date":"2026-04-10T23:20:22","date_gmt":"2026-04-11T06:20:22","guid":{"rendered":"https:\/\/www.songhaiflanges.com\/?p=1554"},"modified":"2026-04-10T23:23:29","modified_gmt":"2026-04-11T06:23:29","slug":"asme-b16-5-flange-size-chart-complete-dimension-guide-for-pipe-flanges","status":"publish","type":"post","link":"https:\/\/www.songhaiflanges.com\/de\/asme-b16-5-flange-size-chart-complete-dimension-guide-for-pipe-flanges\/","title":{"rendered":"ASME B16.5 Flange Size Chart: Complete Dimension Guide for Pipe Flanges"},"content":{"rendered":"<h2>Mastering Flange Dimension Tables for Industrial Piping Systems<\/h2>\n<p>Understanding ASME B16.5 flange dimension charts is essential for engineers, procurement managers, and contractors specifying pipe flanges for oil &#038; gas, petrochemical, water treatment, and industrial applications. This comprehensive guide covers all critical dimensions from 1\/2 inch through 24 inch NPS.<\/p>\n<h2>What Is a Flange Size Chart?<\/h2>\n<p>A flange dimension table provides standardized physical dimensions for flanges across different nominal pipe sizes (NPS) and pressure classes. ASME B16.5 governs flanges from 1\/2 inch through 24 inch, while ASME B16.47 covers large diameter flanges from 26 inch through 60 inch and beyond.<\/p>\n<h2>Critical Flange Dimensions Explained<\/h2>\n<p><strong>Nominal Pipe Size (NPS):<\/strong> NPS is a standardized reference number, NOT an actual measurement. A 2 inch NPS pipe has an outside diameter of 2.375 inch, not 2 inch. Understanding this distinction prevents specification errors.<\/p>\n<p><strong>Flange Outside Diameter (OD):<\/strong> The total outer diameter of the flange itself. OD increases with both pipe size and pressure class. A Class 300# flange has larger OD than Class 150# at the same NPS.<\/p>\n<p><strong>Bolt Circle Diameter (BCD):<\/strong> The diameter of the imaginary circle passing through all bolt hole centers. This is the most critical dimension for mating flanges\u2014mismatched bolt circles mean flanges won&#8217;t connect.<\/p>\n<p><strong>Number of Bolts and Bolt Hole Diameter:<\/strong> Bolt holes are always multiples of 4 (4, 8, 12, 16, 20) for 90\u00b0 assembly orientation. Bolt hole diameter is slightly larger than bolt diameter for installation clearance.<\/p>\n<p><strong>Flange Thickness:<\/strong> Base thickness increases with pressure class. Class 600# flanges are significantly thicker than Class 150# at same NPS to withstand higher internal pressures.<\/p>\n<p><strong>Raised Face (RF) Diameter:<\/strong> The elevated circular seating surface where the gasket contacts. RF diameter is critical for proper gasket selection and compression.<\/p>\n<h2>ASME B16.5 Class 150# Flange Dimensions (Sample)<\/h2>\n<p>1\/2 inch: OD 3.50&#8243;, Thickness 0.38&#8243;, 4 Bolts, Bolt Dia 0.62&#8243;, RF 1\/16&#8243;<\/p>\n<p>1 inch: OD 4.25&#8243;, Thickness 0.50&#8243;, 4 Bolts, Bolt Dia 0.62&#8243;, RF 1\/16&#8243;<\/p>\n<p>2 inch: OD 6.00&#8243;, Thickness 0.69&#8243;, 4 Bolts, Bolt Dia 0.75&#8243;, RF 1\/16&#8243;<\/p>\n<p>4 inch: OD 9.00&#8243;, Thickness 0.88&#8243;, 8 Bolts, Bolt Dia 0.75&#8243;, RF 1\/16&#8243;<\/p>\n<p>6 inch: OD 11.00&#8243;, Thickness 0.94&#8243;, 8 Bolts, Bolt Dia 0.88&#8243;, RF 1\/16&#8243;<\/p>\n<p>8 inch: OD 13.50&#8243;, Thickness 1.06&#8243;, 8 Bolts, Bolt Dia 0.88&#8243;, RF 1\/16&#8243;<\/p>\n<p>10 inch: OD 16.00&#8243;, Thickness 1.12&#8243;, 12 Bolts, Bolt Dia 1.00&#8243;, RF 1\/16&#8243;<\/p>\n<p>12 inch: OD 19.00&#8243;, Thickness 1.19&#8243;, 12 Bolts, Bolt Dia 1.00&#8243;, RF 1\/16&#8243;<\/p>\n<p>All dimensions in inches per ASME B16.5 standards<\/p>\n<h2>Pressure Class Impact on Dimensions<\/h2>\n<p>WARNING: Flanges at same NPS but different pressure classes are NOT interchangeable!<\/p>\n<p>A 4 inch Class 300# flange has larger outside diameter, larger bolt circle diameter, more bolt holes, and greater thickness compared to a 4 inch Class 150# flange. They will not bolt together.<\/p>\n<h2>ASME B16.5 vs ASME B16.47 Standards<\/h2>\n<p><strong>ASME B16.5:<\/strong> Covers 1\/2 inch through 24 inch NPS. Pressure classes: 150#, 300#, 400#, 600#, 900#, 1500#, 2500#. Most common industrial standard.<\/p>\n<p><strong>ASME B16.47:<\/strong> Covers 26 inch through 60 inch NPS (large diameter). Series A (MSS SP-44): Heavier, more robust. Series B (API 605): Lighter weight. Used for major transmission pipelines, large vessels.<\/p>\n<h2>Flange Type Dimension Variations<\/h2>\n<ul>\n<li><strong>Weld Neck:<\/strong> Hub dimensions, tapered bore for smooth flow transition<\/li>\n<li><strong>Slip-On:<\/strong> Shorter hub, slides over pipe then welded<\/li>\n<li><strong>Socket Weld:<\/strong> Internal socket for pipe insertion<\/li>\n<li><strong>Threaded:<\/strong> Internal threads, no welding required<\/li>\n<li><strong>Lap Joint:<\/strong> Stub end with backing flange<\/li>\n<li><strong>Blind:<\/strong> No bore, used to close pipe ends<\/li>\n<\/ul>\n<h2>Field Verification Tips<\/h2>\n<ol>\n<li>Measure existing flange OD and bolt circle before ordering replacements<\/li>\n<li>Count bolt holes and measure bolt diameter<\/li>\n<li>Check pressure class stamping (may be worn or illegible)<\/li>\n<li>Verify flange type (weld neck, slip-on, etc.)<\/li>\n<li>Confirm facing type (RF, FF, RTJ)<\/li>\n<li>Material grade marking for corrosion resistance verification<\/li>\n<\/ol>\n<h2>Material Specifications for Flanges<\/h2>\n<ul>\n<li><strong>A105:<\/strong> Carbon steel for general service<\/li>\n<li><strong>SA-182 F304\/F304L:<\/strong> 304 stainless steel for corrosion resistance<\/li>\n<li><strong>SA-182 F316\/F316L:<\/strong> 316 stainless for chloride environments<\/li>\n<li><strong>A350 LF2:<\/strong> Low-temperature carbon steel for cryogenic service<\/li>\n<li><strong>SA-182 F11\/F22\/F91:<\/strong> Chrome-moly for high-temperature applications<\/li>\n<\/ul>\n<h2>Songhai Flanges Dimensional Accuracy Guarantee<\/h2>\n<p>All Songhai flanges are manufactured to exact ASME B16.5 and ASME B16.47 tolerances with full certification. We provide complete dimension charts for all pressure classes and materials, ensuring perfect interchangeability with existing piping systems.<\/p>\n<p><strong>WhatsApp:<\/strong>\u00a0+86-18658777855<\/p>\n<p><strong>Email:<\/strong>\u00a01007788887@qq.com<\/p>\n<p><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>ASME B16.5 Flange Size Chart: Complete Dimension Guide for Pipe Flanges<\/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":[122,157,154,155,121,124,156,158,97,104],"class_list":["post-1554","post","type-post","status-publish","format-standard","hentry","category-3-news","tag-asme-b16-5","tag-bolt-circle","tag-carbon-steel","tag-flange-dimensions","tag-flange-size-chart","tag-nps","tag-pipe-flanges","tag-pressure-class","tag-stainless-steel","tag-weld-neck"],"_links":{"self":[{"href":"https:\/\/www.songhaiflanges.com\/de\/wp-json\/wp\/v2\/posts\/1554","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.songhaiflanges.com\/de\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.songhaiflanges.com\/de\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.songhaiflanges.com\/de\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.songhaiflanges.com\/de\/wp-json\/wp\/v2\/comments?post=1554"}],"version-history":[{"count":2,"href":"https:\/\/www.songhaiflanges.com\/de\/wp-json\/wp\/v2\/posts\/1554\/revisions"}],"predecessor-version":[{"id":1568,"href":"https:\/\/www.songhaiflanges.com\/de\/wp-json\/wp\/v2\/posts\/1554\/revisions\/1568"}],"wp:attachment":[{"href":"https:\/\/www.songhaiflanges.com\/de\/wp-json\/wp\/v2\/media?parent=1554"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.songhaiflanges.com\/de\/wp-json\/wp\/v2\/categories?post=1554"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.songhaiflanges.com\/de\/wp-json\/wp\/v2\/tags?post=1554"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}