{"id":15775,"date":"2026-09-22T02:42:17","date_gmt":"2026-09-22T02:42:17","guid":{"rendered":"https:\/\/npt-lok.com\/?p=15775"},"modified":"2026-09-22T02:42:17","modified_gmt":"2026-09-22T02:42:17","slug":"pipe-thread-types-and-size-explained","status":"publish","type":"post","link":"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/","title":{"rendered":"Pipe Thread Types and Size Explained"},"content":{"rendered":"<p><span style=\"font-weight: 400;\">Pipe thread types include<\/span><a href=\"https:\/\/npt-lok.com\/fa_ir\/%d8%a7%d8%aa%d8%b5%d8%a7%d9%84%d8%a7%d8%aa-%d9%84%d9%88%d9%84%d9%87-%d8%a7%d8%a8%d8%b2%d8%a7%d8%b1-%d8%af%d9%82%db%8c%d9%82\/%d8%a7%d8%aa%d8%b5%d8%a7%d9%84%d8%a7%d8%aa-npt\/\"><span style=\"font-weight: 400;\"> \u067e\u06cc\u0645\u0627\u0646 \u0645\u0646\u0639 \u06af\u0633\u062a\u0631\u0634 \u0633\u0644\u0627\u062d\u200c\u0647\u0627\u06cc \u0647\u0633\u062a\u0647\u200c\u0627\u06cc<\/span><\/a><span style=\"font-weight: 400;\">, NPTF, BSPP, BSPT, metric, SAE and JIS connections. They differ in thread angle, taper, pitch, size designation and sealing method. Before selecting a fitting, you should identify all these features, not just the measured thread diameter. Different threads can sometimes engage for a few turns without forming a correct or pressure-tight connection.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone  wp-image-15776\" src=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/09\/Pipe-thread-types.png\" alt=\"\" width=\"917\" height=\"370\" srcset=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/09\/Pipe-thread-types.png 570w, https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/09\/Pipe-thread-types-18x7.png 18w\" sizes=\"auto, (max-width: 917px) 100vw, 917px\" \/><\/p>\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_88 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">\u0641\u0647\u0631\u0633\u062a \u0645\u0637\u0627\u0644\u0628<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"\u062a\u063a\u06cc\u06cc\u0631 \u0648\u0636\u0639\u06cc\u062a \u0641\u0647\u0631\u0633\u062a \u0645\u0637\u0627\u0644\u0628\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">\u0636\u0627\u0645\u0646<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewbox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewbox=\"0 0 24 24\" version=\"1.2\" baseprofile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/#What_Is_a_Pipe_Thread\" >What Is a Pipe Thread?<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/#Tapered_Pipe_Threads\" >Tapered Pipe Threads<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/#Parallel_or_Straight_Threads\" >Parallel or Straight Threads<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/#Common_Types_of_Pipe_Threads\" >Common Types of Pipe Threads<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/#NPT_and_NPTF_Threads\" >NPT and NPTF Threads<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/#British_Pipe_Threads\" >British Pipe Threads<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/#Metric_Threads\" >Metric Threads<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/#SAE_Threads_and_Hydraulic_Connections\" >SAE Threads and Hydraulic Connections<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/#JIS_Pipe_Threads\" >JIS Pipe Threads<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/#Pipe_Thread_Types_Comparison_Chart\" >Pipe Thread Types Comparison Chart<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/#How_to_Read_Pipe_Thread_Sizes\" >How to Read Pipe Thread Sizes<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-12\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/#Nominal_Size_Is_Not_the_Measured_Diameter\" >Nominal Size Is Not the Measured Diameter<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-13\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/#Pitch_and_Threads_per_Inch\" >Pitch and Threads per Inch<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-14\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/#Common_Thread_Marking_Examples\" >Common Thread Marking Examples<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-15\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/#How_to_Identify_Pipe_Threads\" >How to Identify Pipe Threads\u00a0<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-16\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/#What_to_Check_Before_Selecting_a_Fitting\" >What to Check Before Selecting a Fitting<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-17\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/#FAQ\" >\u0633\u0648\u0627\u0644\u0627\u062a \u0645\u062a\u062f\u0627\u0648\u0644<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-18\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/#Contact_Us\" >\u062a\u0645\u0627\u0633 \u0628\u0627 \u0645\u0627<\/a><\/li><\/ul><\/nav><\/div>\n<h2><span class=\"ez-toc-section\" id=\"What_Is_a_Pipe_Thread\"><\/span><span style=\"font-weight: 400;\">What Is a Pipe Thread?<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span style=\"font-weight: 400;\">A pipe thread connects a pipe, <\/span><a href=\"https:\/\/npt-lok.com\/fa_ir\/instrumentation-valve\/\"><span style=\"font-weight: 400;\">valve<\/span><\/a><span style=\"font-weight: 400;\">, <\/span><a href=\"https:\/\/npt-lok.com\/fa_ir\/%d8%a7%d8%aa%d8%b5%d8%a7%d9%84%d8%a7%d8%aa-%d9%81%d8%b4%d8%b1%d8%af%d9%87-%d8%b3%d8%a7%d8%b2%db%8c\/\"><span style=\"font-weight: 400;\">fitting<\/span><\/a><span style=\"font-weight: 400;\">, <\/span><a href=\"https:\/\/npt-lok.com\/fa_ir\/%d8%b4%db%8c%d8%b1-%d9%85%d9%86%db%8c%d9%81%d9%88%d9%84%d8%af\/\"><span style=\"font-weight: 400;\">manifold<\/span><\/a><span style=\"font-weight: 400;\"> or instrument port. Some pipe threads both connect and seal the joint. Others only hold the parts together while an O-ring, gasket or metal seat creates the pressure seal.<\/span><\/p>\n<h3><span class=\"ez-toc-section\" id=\"Tapered_Pipe_Threads\"><\/span><span style=\"font-weight: 400;\">Tapered Pipe Threads<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Tapered threads increase in diameter along their length. NPT and BSPT are common examples. Tightening produces interference between the male and female threads, normally with a suitable thread sealant.<\/span><\/p>\n<h3><span class=\"ez-toc-section\" id=\"Parallel_or_Straight_Threads\"><\/span><span style=\"font-weight: 400;\">Parallel or Straight Threads<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Parallel threads maintain a constant diameter. BSPP, SAE O-ring boss and many metric connections use parallel threads. These connections generally seal with an O-ring, washer, gasket or shaped sealing surface.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">One important exception is the ISO 7-1 Rp parallel female thread, which is intended to mate with an R tapered male thread in a connection that seals at the threads.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Thread tape cannot replace a missing or damaged O-ring or gasket.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-15777 aligncenter\" src=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/09\/Parallel-vs-Tapered-thread.jpg\" alt=\"\" width=\"600\" height=\"300\" srcset=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/09\/Parallel-vs-Tapered-thread.jpg 600w, https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/09\/Parallel-vs-Tapered-thread-18x9.jpg 18w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Common_Types_of_Pipe_Threads\"><\/span><span style=\"font-weight: 400;\">Common Types of Pipe Threads<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span style=\"font-weight: 400;\">Types of pipe threads fall into five major families. Each family has its own standard, thread angle, and sealing method.<\/span><\/p>\n<h3><span class=\"ez-toc-section\" id=\"NPT_and_NPTF_Threads\"><\/span><span style=\"font-weight: 400;\">NPT and NPTF Threads<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400;\">NPT stands for National Pipe Taper. It is a 60\u00b0 tapered thread defined by ASME B1.20.1 and widely used in North American instrumentation, process piping and general industrial equipment.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">An NPT joint normally requires an approved paste or tape sealant to fill the spiral leak path and reduce galling during assembly.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">NPTF is a dryseal thread covered by ASME B1.20.3. It uses controlled crest and root interference to reduce leakage. Do not assume that every NPTF application must be assembled without sealant; follow the equipment manufacturer\u2019s instructions.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-15779 aligncenter\" src=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/09\/NPT-vs-NPTF.webp\" alt=\"\" width=\"785\" height=\"345\" srcset=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/09\/NPT-vs-NPTF.webp 1129w, https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/09\/NPT-vs-NPTF-768x338.webp 768w, https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/09\/NPT-vs-NPTF-18x8.webp 18w\" sizes=\"auto, (max-width: 785px) 100vw, 785px\" \/><\/p>\n<h3><span class=\"ez-toc-section\" id=\"British_Pipe_Threads\"><\/span><span style=\"font-weight: 400;\">British Pipe Threads<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400;\">British pipe threads are Whitworth threads with a 55\u00b0 thread angle. They are divided into two main groups.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">BSPP, commonly marked G, is parallel. The thread holds the components together, while a gasket, bonded washer or O-ring provides the seal.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">BSPT is tapered. Under ISO 7-1, R identifies a tapered male thread, Rp a parallel female thread and Rc a tapered female thread. R male threads are intended to mate with correctly specified Rp or Rc female threads.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">NPT and BSPT may engage for a few turns, but they are not interchangeable. NPT has a 60\u00b0 thread form, while BSP uses 55\u00b0. Pitch and profile can also differ. See our guide to <\/span><a href=\"https:\/\/docs.google.com\/document\/u\/0\/d\/1kcMu2BiP7QbUajM9cqjHLqyHwdaMo94kRm12cj9Tk2E\/edit\"><span style=\"font-weight: 400;\">NPT vs BSP threads<\/span><\/a><span style=\"font-weight: 400;\"> for a detailed comparison.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-15481 aligncenter\" src=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/07\/NPT-vs.BSP\uff08angle\uff09\uff09.png\" alt=\"NPT vs. BSP\uff08angle\uff09\" width=\"282\" height=\"266\" srcset=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/07\/NPT-vs.BSP\uff08angle\uff09\uff09.png 399w, https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/07\/NPT-vs.BSP\uff08angle\uff09\uff09-13x12.png 13w\" sizes=\"auto, (max-width: 282px) 100vw, 282px\" \/><\/p>\n<h3><span class=\"ez-toc-section\" id=\"Metric_Threads\"><\/span><span style=\"font-weight: 400;\">Metric Threads<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400;\">A metric thread designation states the nominal major diameter and pitch in millimeters. For example, M14 \u00d7 1.5 indicates a nominal major diameter of 14 mm and a pitch of 1.5 mm.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">ISO metric threads have a 60\u00b0 thread angle. However, the metric thread designation alone does not identify the sealing method. Depending on the connection design, sealing may use an O-ring, washer or cone seat.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Two fittings with the same metric thread size may still have incompatible sealing surfaces. Confirm both the thread and the complete connection geometry.<\/span><\/p>\n<h3><span class=\"ez-toc-section\" id=\"SAE_Threads_and_Hydraulic_Connections\"><\/span><span style=\"font-weight: 400;\">SAE Threads and Hydraulic Connections<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400;\">SAE connections often use parallel UN or UNF threads. SAE O-ring boss connections seal with an O-ring; JIC and SAE flare fittings seal at a metal seat. The 37\u00b0 or 45\u00b0 value describes the flare seat, not the thread angle.<\/span><\/p>\n<h3><span class=\"ez-toc-section\" id=\"JIS_Pipe_Threads\"><\/span><span style=\"font-weight: 400;\">JIS Pipe Threads<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400;\">JIS pipe threads are commonly encountered on Japanese equipment. JIS B 0202 covers parallel pipe threads, while JIS B 0203 covers taper pipe threads.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Older drawings may use PT or PF markings, while other drawings may show G, R, Rp or Rc. Check the referenced standard and drawing edition before selecting a mating fitting.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Pipe_Thread_Types_Comparison_Chart\"><\/span><span style=\"font-weight: 400;\">Pipe Thread Types Comparison Chart<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span style=\"font-weight: 400;\">To compare different types of pipe threads, use the table below. It covers the most common standards in instrumentation, small-bore process, hydraulic, and general piping.<\/span><\/p>\n<table>\n<tbody>\n<tr>\n<td><span style=\"font-weight: 400;\">Thread Type<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Standard<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Angle<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Taper \/ Parallel<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Sealing Method<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Common Applications<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">\u067e\u06cc\u0645\u0627\u0646 \u0645\u0646\u0639 \u06af\u0633\u062a\u0631\u0634 \u0633\u0644\u0627\u062d\u200c\u0647\u0627\u06cc \u0647\u0633\u062a\u0647\u200c\u0627\u06cc<\/span><\/td>\n<td><span style=\"font-weight: 400;\">ASME B1.20.1<\/span><\/td>\n<td><span style=\"font-weight: 400;\">60\u00b0<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Tapered<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Sealant<\/span><\/td>\n<td><span style=\"font-weight: 400;\">US\/Canada gas, water, oil<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">NPTF<\/span><\/td>\n<td><span style=\"font-weight: 400;\">ASME B1.20.3<\/span><\/td>\n<td><span style=\"font-weight: 400;\">60\u00b0<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Tapered<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Dry seal (metal-to-metal)<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Fuel, hydraulic, no sealant<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">BSPP \/ G<\/span><\/td>\n<td><span style=\"font-weight: 400;\">ISO 228-1<\/span><\/td>\n<td><span style=\"font-weight: 400;\">55\u00b0<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Parallel<\/span><\/td>\n<td><span style=\"font-weight: 400;\">O-ring \/ gasket<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Europe, Asia, pneumatic<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">BSPT \/ R<\/span><\/td>\n<td><span style=\"font-weight: 400;\">ISO 7-1<\/span><\/td>\n<td><span style=\"font-weight: 400;\">55\u00b0<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Tapered<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Sealant<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Europe, Asia, general piping<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">Rp<\/span><\/td>\n<td><span style=\"font-weight: 400;\">ISO 7-1<\/span><\/td>\n<td><span style=\"font-weight: 400;\">55\u00b0<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Parallel female<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Sealant with R male<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Mates with BSPT male<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">Rc<\/span><\/td>\n<td><span style=\"font-weight: 400;\">ISO 7-1<\/span><\/td>\n<td><span style=\"font-weight: 400;\">55\u00b0<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Tapered female<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Sealant with R male<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Mates with BSPT male<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">Metric<\/span><\/td>\n<td><span style=\"font-weight: 400;\">ISO 68-1<\/span><\/td>\n<td><span style=\"font-weight: 400;\">60\u00b0<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Parallel<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Washer \/ O-ring<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Global machinery, automotive<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">SAE J512<\/span><\/td>\n<td><span style=\"font-weight: 400;\">SAE J512<\/span><\/td>\n<td><span style=\"font-weight: 400;\">45\u00b0<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Tapered flare<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Flare seat<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Automotive, low pressure<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">SAE J514<\/span><\/td>\n<td><span style=\"font-weight: 400;\">SAE J514<\/span><\/td>\n<td><span style=\"font-weight: 400;\">37\u00b0<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Flare<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Flare seat<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Hydraulic<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">SAE J1926<\/span><\/td>\n<td><span style=\"font-weight: 400;\">ISO 11926<\/span><\/td>\n<td><span style=\"font-weight: 400;\">\u2014<\/span><\/td>\n<td><span style=\"font-weight: 400;\">\u0645\u0633\u062a\u0642\u06cc\u0645<\/span><\/td>\n<td><span style=\"font-weight: 400;\">O-ring boss<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Hydraulic ports<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">JIS B0203<\/span><\/td>\n<td><span style=\"font-weight: 400;\">JIS B0203<\/span><\/td>\n<td><span style=\"font-weight: 400;\">55\u00b0<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Tapered<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Sealant<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Japan, similar to BSPT<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">JIS B0202<\/span><\/td>\n<td><span style=\"font-weight: 400;\">JIS B0202<\/span><\/td>\n<td><span style=\"font-weight: 400;\">55\u00b0<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Parallel<\/span><\/td>\n<td><span style=\"font-weight: 400;\">O-ring \/ gasket<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Japan, similar to BSPP<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2><span class=\"ez-toc-section\" id=\"How_to_Read_Pipe_Thread_Sizes\"><\/span><span style=\"font-weight: 400;\">How to Read Pipe Thread Sizes<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<h3><span class=\"ez-toc-section\" id=\"Nominal_Size_Is_Not_the_Measured_Diameter\"><\/span><span style=\"font-weight: 400;\">Nominal Size Is Not the Measured Diameter<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Inch pipe thread sizes, such as 1\/4 NPT and G 1\/2, are nominal designations. They do not mean that the external thread diameter measures exactly 1\/4 inch or 1\/2 inch.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">For tapered threads, the measured diameter also changes with the measurement position. Compare the measurement with the correct thread standard rather than converting the nominal size directly into millimeters.<\/span><\/p>\n<h3><span class=\"ez-toc-section\" id=\"Pitch_and_Threads_per_Inch\"><\/span><span style=\"font-weight: 400;\">Pitch and Threads per Inch<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Inch threads commonly express pitch as threads per inch (TPI). Metric threads normally express pitch as the distance between adjacent thread crests in millimeters.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">For an inch thread, pitch in millimeters can be calculated as:<\/span><\/p>\n<p><b>Pitch (mm) = 25.4 \u00f7 TPI<\/b><\/p>\n<p><span style=\"font-weight: 400;\">This conversion describes spacing only. Equal or similar pitch does not establish compatibility between different thread standards.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Common_Thread_Marking_Examples\"><\/span><span style=\"font-weight: 400;\">Common Thread Marking Examples<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<table>\n<tbody>\n<tr>\n<td><span style=\"font-weight: 400;\">Marking<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Meaning<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">1\/4-18 NPT<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Nominal 1\/4-inch NPT thread, 18 TPI\u00a0<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">G 1\/4<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Nominal 1\/4-inch parallel pipe thread under ISO 228-1 \/ ISO 228-1<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">R 1\/4<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Nominal 1\/4-inch tapered male pipe thread under ISO 7-1 \/ ISO 7-1<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">M14 \u00d7 1.5<\/span><\/td>\n<td><span style=\"font-weight: 400;\">14 mm nominal major diameter, 1.5 mm pitch<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">7\/16-20<\/span><\/td>\n<td><span style=\"font-weight: 400;\">7\/16-inch nominal major diameter, 20 TPI; additional connection details are required<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><span style=\"font-weight: 400;\">A complete order should specify more than a size. Include the thread standard, male or female form and sealing arrangement.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"How_to_Identify_Pipe_Threads\"><\/span><span style=\"font-weight: 400;\">How to Identify Pipe Threads\u00a0<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span style=\"font-weight: 400;\">Check markings and documentation. Look for a thread designation, drawing or equipment specification.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Determine whether it is tapered or parallel. Compare diameters at different positions along the thread.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Measure the diameter. Measure the male thread\u2019s outside diameter or the female thread\u2019s inside diameter as required by the identification guide.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Measure the pitch. Use a thread pitch gauge to determine TPI or metric pitch.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Check the thread profile. Confirm the specified angle and form.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Inspect the sealing features. Look for an O-ring groove, gasket face, cone or flare seat.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Confirm against the correct standard. Check dimensions, tolerances and the complete mating connection.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Do not use a trial fit as proof of compatibility. Different threads can sometimes engage for a few turns without forming a correct or pressure-tight connection.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"What_to_Check_Before_Selecting_a_Fitting\"><\/span><span style=\"font-weight: 400;\">What to Check Before Selecting a Fitting<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span style=\"font-weight: 400;\">Thread compatibility is only one part of fitting selection. Also confirm:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-checked=\"false\" aria-level=\"1\"><span style=\"font-weight: 400;\">The connection specification and size at each end.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-checked=\"false\" aria-level=\"1\"><a href=\"https:\/\/npt-lok.com\/fa_ir\/%d9%86%d8%ae-%d9%86%d8%b1-%d8%af%d8%b1-%d9%85%d9%82%d8%a7%d8%a8%d9%84-%d9%86%d8%ae-%d9%85%d8%a7%d8%af%d9%87\/\"><span style=\"font-weight: 400;\">Male or female configuration<\/span><\/a><span style=\"font-weight: 400;\">.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-checked=\"false\" aria-level=\"1\"><span style=\"font-weight: 400;\">The required fitting shape, such as a <\/span><a href=\"https:\/\/npt-lok.com\/fa_ir\/%d8%a7%d8%aa%d8%b5%d8%a7%d9%84%d8%a7%d8%aa-%d9%84%d9%88%d9%84%d9%87-%d8%a7%d8%a8%d8%b2%d8%a7%d8%b1-%d8%af%d9%82%db%8c%d9%82\/pipe-nipple\/\"><span style=\"font-weight: 400;\">\u0646\u0648\u06a9 \u0633\u06cc\u0646\u0647<\/span><\/a><span style=\"font-weight: 400;\">, <\/span><a href=\"https:\/\/npt-lok.com\/fa_ir\/reducing-adapters\/\"><span style=\"font-weight: 400;\">adapter<\/span><\/a><span style=\"font-weight: 400;\">, <\/span><a href=\"https:\/\/npt-lok.com\/fa_ir\/%d8%a7%d8%aa%d8%b5%d8%a7%d9%84%d8%a7%d8%aa-%d9%84%d9%88%d9%84%d9%87\/%d8%a2%d8%b1%d9%86%d8%ac-%d9%85%d8%b1%d8%af%d8%a7%d9%86%d9%87\/\"><span style=\"font-weight: 400;\">elbow<\/span><\/a><span style=\"font-weight: 400;\"> \u06cc\u0627<\/span><a href=\"https:\/\/npt-lok.com\/fa_ir\/%d8%a7%d8%aa%d8%b5%d8%a7%d9%84%d8%a7%d8%aa-%d9%84%d9%88%d9%84%d9%87\/%d8%a7%d8%aa%d8%b5%d8%a7%d9%84%d8%a7%d8%aa-%d8%b3%d9%87-%d8%b1%d8%a7%d9%87%db%8c-%db%8c%d9%88%d9%86%db%8c%d9%88%d9%86\/\"><span style=\"font-weight: 400;\"> \u062a\u06cc<\/span><\/a><span style=\"font-weight: 400;\">.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-checked=\"false\" aria-level=\"1\"><span style=\"font-weight: 400;\">Material compatibility with the process fluid.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-checked=\"false\" aria-level=\"1\"><span style=\"font-weight: 400;\">Working pressure and operating temperature.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-checked=\"false\" aria-level=\"1\"><span style=\"font-weight: 400;\">Seal material and assembly requirements.<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">Size availability and pressure ratings vary by fitting series, material and configuration. Do not apply one product\u2019s maximum size or pressure rating to every fitting with the same thread type.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Where an O-ring or gasket is used, its temperature and fluid compatibility may limit the complete connection.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"FAQ\"><\/span><span style=\"font-weight: 400;\">\u0633\u0648\u0627\u0644\u0627\u062a \u0645\u062a\u062f\u0627\u0648\u0644<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span style=\"font-weight: 400;\">Q1. What are the main types of pipe threads?<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The main types of pipe threads are NPT, NPTF, BSPP (G), BSPT (R), Metric, SAE, and JIS.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Q2. Are British pipe threads compatible with NPT?<\/span><\/p>\n<p><span style=\"font-weight: 400;\">No. NPT has a 60\u00b0 angle; British pipe threads have a 55\u00b0 angle. They are not interchangeable.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Q3. Is a 1\/2-inch pipe thread 12.7 mm in outside diameter?<\/span><\/p>\n<p><span style=\"font-weight: 400;\">No. The 1\/2-inch designation is a nominal pipe size. The actual external thread diameter is larger than 12.7 mm and depends on the standard and, for tapered threads, the measurement position.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Q4. What are the different types of pipe threads for hydraulic fittings?<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Common hydraulic threads include NPT, NPTF, SAE J514 (37\u00b0 flare), SAE J1926 (O-ring boss), and BSPP (G).<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Q5. Do all threaded connections require thread tape?<\/span><\/p>\n<p><span style=\"font-weight: 400;\">No. NPT and BSPT connections normally use suitable thread sealant, which may be tape or paste depending on the application. Connections designed to seal with an O-ring, gasket or flare seat rely on those features instead. Follow the manufacturer\u2019s assembly instructions.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Contact_Us\"><\/span><span style=\"font-weight: 400;\">\u062a\u0645\u0627\u0633 \u0628\u0627 \u0645\u0627<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span style=\"font-weight: 400;\">NPTLOK offers high-quality NPT and BSPP thread fittings to help you build more reliable, longer-lasting connections. If you require other thread types, we can also provide them. NPTLOK manufactures<\/span><a href=\"https:\/\/npt-lok.com\/fa_ir\/%d8%a7%d8%aa%d8%b5%d8%a7%d9%84%d8%a7%d8%aa-%d9%81%d8%b4%d8%b1%d8%af%d9%87-%d8%b3%d8%a7%d8%b2%db%8c\/\"><span style=\"font-weight: 400;\"> instrumentation tube fittings<\/span><\/a><span style=\"font-weight: 400;\"> \u0648<\/span><a href=\"https:\/\/npt-lok.com\/fa_ir\/instrumentation-valve\/\"> <span style=\"font-weight: 400;\">valves<\/span><\/a><span style=\"font-weight: 400;\"> \u0628\u06cc\u0634 \u0627\u0632 20 \u0633\u0627\u0644 \u0633\u0627\u0628\u0642\u0647 \u0648 \u062f\u0627\u0631\u0627\u06cc \u06af\u0648\u0627\u0647\u06cc\u0646\u0627\u0645\u0647 ISO\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">We offer a full range of NPT and BSPP thread fittings up to 2\u2033. For any inquiries or to download<\/span><a href=\"https:\/\/npt-lok.com\/fa_ir\/product-catalog-download\/\"> <span style=\"font-weight: 400;\">our product catalog<\/span><\/a><span style=\"font-weight: 400;\">, please feel free to<\/span><a href=\"https:\/\/npt-lok.com\/fa_ir\/%d8%a8%d8%b1%d8%a7%db%8c-%d8%af%d8%b1%db%8c%d8%a7%d9%81%d8%aa-%d9%82%db%8c%d9%85%d8%aa-%d8%aa%d9%85%d8%a7%d8%b3-%d8%a8%da%af%db%8c%d8%b1%db%8c%d8%af\/\"> <span style=\"font-weight: 400;\">\u0628\u0627 \u0645\u0627 \u062a\u0645\u0627\u0633 \u0628\u06af\u06cc\u0631\u06cc\u062f<\/span><\/a><span style=\"font-weight: 400;\">.<\/span><\/p>","protected":false},"excerpt":{"rendered":"<p>Pipe thread types include NPT, NPTF, BSPP, BSPT, metric, SAE and JIS connections. They differ in thread angle, taper, pitch, size designation and sealing method. Before selecting a fitting, you should identify all these features, not just the measured thread diameter. Different threads can sometimes engage for a few turns without forming a correct or [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"default","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[1],"tags":[],"class_list":["post-15775","post","type-post","status-publish","format-standard","hentry","category-blog"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.7 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Pipe Thread Types and Size Explained - NPTLOK Instrumentation Tube Fittings and Valves<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/\" \/>\n<meta property=\"og:locale\" content=\"fa_IR\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Pipe Thread Types and Size Explained - NPTLOK Instrumentation Tube Fittings and Valves\" \/>\n<meta property=\"og:description\" content=\"Pipe thread types include NPT, NPTF, BSPP, BSPT, metric, SAE and JIS connections. They differ in thread angle, taper, pitch, size designation and sealing method. Before selecting a fitting, you should identify all these features, not just the measured thread diameter. Different threads can sometimes engage for a few turns without forming a correct or [&hellip;]\" \/>\n<meta property=\"og:url\" content=\"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/\" \/>\n<meta property=\"og:site_name\" content=\"NPTLOK Instrumentation Tube Fittings and Valves\" \/>\n<meta property=\"article:published_time\" content=\"2026-09-22T02:42:17+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/09\/Pipe-thread-types.png\" \/>\n\t<meta property=\"og:image:width\" content=\"570\" \/>\n\t<meta property=\"og:image:height\" content=\"230\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/png\" \/>\n<meta name=\"author\" content=\"NPTLOK\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"\u0646\u0648\u0634\u062a\u0647\u200c\u0634\u062f\u0647 \u0628\u062f\u0633\u062a\" \/>\n\t<meta name=\"twitter:data1\" content=\"NPTLOK\" \/>\n\t<meta name=\"twitter:label2\" content=\"\u0632\u0645\u0627\u0646 \u062a\u0642\u0631\u06cc\u0628\u06cc \u0628\u0631\u0627\u06cc \u062e\u0648\u0627\u0646\u062f\u0646\" \/>\n\t<meta name=\"twitter:data2\" content=\"8 \u062f\u0642\u06cc\u0642\u0647\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/npt-lok.com\\\/pipe-thread-types-and-size-explained\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/npt-lok.com\\\/pipe-thread-types-and-size-explained\\\/\"},\"author\":{\"name\":\"NPTLOK\",\"@id\":\"https:\\\/\\\/npt-lok.com\\\/#\\\/schema\\\/person\\\/952fa6592fb0069202b037e7605d4e19\"},\"headline\":\"Pipe Thread Types and Size Explained\",\"datePublished\":\"2026-09-22T02:42:17+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/npt-lok.com\\\/pipe-thread-types-and-size-explained\\\/\"},\"wordCount\":1479,\"publisher\":{\"@id\":\"https:\\\/\\\/npt-lok.com\\\/#organization\"},\"image\":{\"@id\":\"https:\\\/\\\/npt-lok.com\\\/pipe-thread-types-and-size-explained\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/npt-lok.com\\\/wp-content\\\/uploads\\\/2026\\\/09\\\/Pipe-thread-types.png\",\"articleSection\":[\"Blog\"],\"inLanguage\":\"fa-IR\"},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/npt-lok.com\\\/pipe-thread-types-and-size-explained\\\/\",\"url\":\"https:\\\/\\\/npt-lok.com\\\/pipe-thread-types-and-size-explained\\\/\",\"name\":\"Pipe Thread Types and Size Explained - NPTLOK Instrumentation Tube Fittings and Valves\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/npt-lok.com\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/npt-lok.com\\\/pipe-thread-types-and-size-explained\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/npt-lok.com\\\/pipe-thread-types-and-size-explained\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/npt-lok.com\\\/wp-content\\\/uploads\\\/2026\\\/09\\\/Pipe-thread-types.png\",\"datePublished\":\"2026-09-22T02:42:17+00:00\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/npt-lok.com\\\/pipe-thread-types-and-size-explained\\\/#breadcrumb\"},\"inLanguage\":\"fa-IR\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/npt-lok.com\\\/pipe-thread-types-and-size-explained\\\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"fa-IR\",\"@id\":\"https:\\\/\\\/npt-lok.com\\\/pipe-thread-types-and-size-explained\\\/#primaryimage\",\"url\":\"https:\\\/\\\/npt-lok.com\\\/wp-content\\\/uploads\\\/2026\\\/09\\\/Pipe-thread-types.png\",\"contentUrl\":\"https:\\\/\\\/npt-lok.com\\\/wp-content\\\/uploads\\\/2026\\\/09\\\/Pipe-thread-types.png\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/npt-lok.com\\\/pipe-thread-types-and-size-explained\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/npt-lok.com\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Pipe Thread Types and Size Explained\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/npt-lok.com\\\/#website\",\"url\":\"https:\\\/\\\/npt-lok.com\\\/\",\"name\":\"NPTLOK Instrumentation Tube Fittings and Valves\",\"description\":\"\",\"publisher\":{\"@id\":\"https:\\\/\\\/npt-lok.com\\\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/npt-lok.com\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"fa-IR\"},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/npt-lok.com\\\/#organization\",\"name\":\"NPTLOK Instrumentation Tube Fittings and Valves\",\"url\":\"https:\\\/\\\/npt-lok.com\\\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"fa-IR\",\"@id\":\"https:\\\/\\\/npt-lok.com\\\/#\\\/schema\\\/logo\\\/image\\\/\",\"url\":\"https:\\\/\\\/npt-lok.com\\\/wp-content\\\/uploads\\\/2022\\\/08\\\/cropped-cropped-NPT-LOK\u9ed1\u767d-e1787037014570.png\",\"contentUrl\":\"https:\\\/\\\/npt-lok.com\\\/wp-content\\\/uploads\\\/2022\\\/08\\\/cropped-cropped-NPT-LOK\u9ed1\u767d-e1787037014570.png\",\"width\":260,\"height\":85,\"caption\":\"NPTLOK Instrumentation Tube Fittings and Valves\"},\"image\":{\"@id\":\"https:\\\/\\\/npt-lok.com\\\/#\\\/schema\\\/logo\\\/image\\\/\"}},{\"@type\":\"Person\",\"@id\":\"https:\\\/\\\/npt-lok.com\\\/#\\\/schema\\\/person\\\/952fa6592fb0069202b037e7605d4e19\",\"name\":\"NPTLOK\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"fa-IR\",\"@id\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/786b349f66bfff9c6f962d1bcfdeec2a96c09c6f1e30f21f2e6c2f994b4d7f5f?s=96&d=mm&r=g\",\"url\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/786b349f66bfff9c6f962d1bcfdeec2a96c09c6f1e30f21f2e6c2f994b4d7f5f?s=96&d=mm&r=g\",\"contentUrl\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/786b349f66bfff9c6f962d1bcfdeec2a96c09c6f1e30f21f2e6c2f994b4d7f5f?s=96&d=mm&r=g\",\"caption\":\"NPTLOK\"},\"url\":\"https:\\\/\\\/npt-lok.com\\\/fa_ir\\\/author\\\/dp_admin\\\/\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Pipe Thread Types and Size Explained - NPTLOK Instrumentation Tube Fittings and Valves","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/","og_locale":"fa_IR","og_type":"article","og_title":"Pipe Thread Types and Size Explained - NPTLOK Instrumentation Tube Fittings and Valves","og_description":"Pipe thread types include NPT, NPTF, BSPP, BSPT, metric, SAE and JIS connections. They differ in thread angle, taper, pitch, size designation and sealing method. Before selecting a fitting, you should identify all these features, not just the measured thread diameter. Different threads can sometimes engage for a few turns without forming a correct or [&hellip;]","og_url":"https:\/\/npt-lok.com\/fa_ir\/pipe-thread-types-and-size-explained\/","og_site_name":"NPTLOK Instrumentation Tube Fittings and Valves","article_published_time":"2026-09-22T02:42:17+00:00","og_image":[{"width":570,"height":230,"url":"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/09\/Pipe-thread-types.png","type":"image\/png"}],"author":"NPTLOK","twitter_card":"summary_large_image","twitter_misc":{"\u0646\u0648\u0634\u062a\u0647\u200c\u0634\u062f\u0647 \u0628\u062f\u0633\u062a":"NPTLOK","\u0632\u0645\u0627\u0646 \u062a\u0642\u0631\u06cc\u0628\u06cc \u0628\u0631\u0627\u06cc \u062e\u0648\u0627\u0646\u062f\u0646":"8 \u062f\u0642\u06cc\u0642\u0647"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/npt-lok.com\/pipe-thread-types-and-size-explained\/#article","isPartOf":{"@id":"https:\/\/npt-lok.com\/pipe-thread-types-and-size-explained\/"},"author":{"name":"NPTLOK","@id":"https:\/\/npt-lok.com\/#\/schema\/person\/952fa6592fb0069202b037e7605d4e19"},"headline":"Pipe Thread Types and Size Explained","datePublished":"2026-09-22T02:42:17+00:00","mainEntityOfPage":{"@id":"https:\/\/npt-lok.com\/pipe-thread-types-and-size-explained\/"},"wordCount":1479,"publisher":{"@id":"https:\/\/npt-lok.com\/#organization"},"image":{"@id":"https:\/\/npt-lok.com\/pipe-thread-types-and-size-explained\/#primaryimage"},"thumbnailUrl":"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/09\/Pipe-thread-types.png","articleSection":["Blog"],"inLanguage":"fa-IR"},{"@type":"WebPage","@id":"https:\/\/npt-lok.com\/pipe-thread-types-and-size-explained\/","url":"https:\/\/npt-lok.com\/pipe-thread-types-and-size-explained\/","name":"Pipe Thread Types and Size Explained - NPTLOK Instrumentation Tube Fittings and Valves","isPartOf":{"@id":"https:\/\/npt-lok.com\/#website"},"primaryImageOfPage":{"@id":"https:\/\/npt-lok.com\/pipe-thread-types-and-size-explained\/#primaryimage"},"image":{"@id":"https:\/\/npt-lok.com\/pipe-thread-types-and-size-explained\/#primaryimage"},"thumbnailUrl":"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/09\/Pipe-thread-types.png","datePublished":"2026-09-22T02:42:17+00:00","breadcrumb":{"@id":"https:\/\/npt-lok.com\/pipe-thread-types-and-size-explained\/#breadcrumb"},"inLanguage":"fa-IR","potentialAction":[{"@type":"ReadAction","target":["https:\/\/npt-lok.com\/pipe-thread-types-and-size-explained\/"]}]},{"@type":"ImageObject","inLanguage":"fa-IR","@id":"https:\/\/npt-lok.com\/pipe-thread-types-and-size-explained\/#primaryimage","url":"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/09\/Pipe-thread-types.png","contentUrl":"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/09\/Pipe-thread-types.png"},{"@type":"BreadcrumbList","@id":"https:\/\/npt-lok.com\/pipe-thread-types-and-size-explained\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/npt-lok.com\/"},{"@type":"ListItem","position":2,"name":"Pipe Thread Types and Size Explained"}]},{"@type":"WebSite","@id":"https:\/\/npt-lok.com\/#website","url":"https:\/\/npt-lok.com\/","name":"\u0627\u062a\u0635\u0627\u0644\u0627\u062a \u0648 \u0634\u06cc\u0631\u0622\u0644\u0627\u062a \u0644\u0648\u0644\u0647 \u0627\u0628\u0632\u0627\u0631 \u062f\u0642\u06cc\u0642 NPTLOK","description":"","publisher":{"@id":"https:\/\/npt-lok.com\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/npt-lok.com\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"fa-IR"},{"@type":"Organization","@id":"https:\/\/npt-lok.com\/#organization","name":"\u0627\u062a\u0635\u0627\u0644\u0627\u062a \u0648 \u0634\u06cc\u0631\u0622\u0644\u0627\u062a \u0644\u0648\u0644\u0647 \u0627\u0628\u0632\u0627\u0631 \u062f\u0642\u06cc\u0642 NPTLOK","url":"https:\/\/npt-lok.com\/","logo":{"@type":"ImageObject","inLanguage":"fa-IR","@id":"https:\/\/npt-lok.com\/#\/schema\/logo\/image\/","url":"https:\/\/npt-lok.com\/wp-content\/uploads\/2022\/08\/cropped-cropped-NPT-LOK\u9ed1\u767d-e1787037014570.png","contentUrl":"https:\/\/npt-lok.com\/wp-content\/uploads\/2022\/08\/cropped-cropped-NPT-LOK\u9ed1\u767d-e1787037014570.png","width":260,"height":85,"caption":"NPTLOK Instrumentation Tube Fittings and Valves"},"image":{"@id":"https:\/\/npt-lok.com\/#\/schema\/logo\/image\/"}},{"@type":"Person","@id":"https:\/\/npt-lok.com\/#\/schema\/person\/952fa6592fb0069202b037e7605d4e19","name":"\u0646\u067e\u062a\u0644\u0648\u06a9","image":{"@type":"ImageObject","inLanguage":"fa-IR","@id":"https:\/\/secure.gravatar.com\/avatar\/786b349f66bfff9c6f962d1bcfdeec2a96c09c6f1e30f21f2e6c2f994b4d7f5f?s=96&d=mm&r=g","url":"https:\/\/secure.gravatar.com\/avatar\/786b349f66bfff9c6f962d1bcfdeec2a96c09c6f1e30f21f2e6c2f994b4d7f5f?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/786b349f66bfff9c6f962d1bcfdeec2a96c09c6f1e30f21f2e6c2f994b4d7f5f?s=96&d=mm&r=g","caption":"NPTLOK"},"url":"https:\/\/npt-lok.com\/fa_ir\/author\/dp_admin\/"}]}},"_links":{"self":[{"href":"https:\/\/npt-lok.com\/fa_ir\/wp-json\/wp\/v2\/posts\/15775","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/npt-lok.com\/fa_ir\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/npt-lok.com\/fa_ir\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/npt-lok.com\/fa_ir\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/npt-lok.com\/fa_ir\/wp-json\/wp\/v2\/comments?post=15775"}],"version-history":[{"count":1,"href":"https:\/\/npt-lok.com\/fa_ir\/wp-json\/wp\/v2\/posts\/15775\/revisions"}],"predecessor-version":[{"id":15780,"href":"https:\/\/npt-lok.com\/fa_ir\/wp-json\/wp\/v2\/posts\/15775\/revisions\/15780"}],"wp:attachment":[{"href":"https:\/\/npt-lok.com\/fa_ir\/wp-json\/wp\/v2\/media?parent=15775"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/npt-lok.com\/fa_ir\/wp-json\/wp\/v2\/categories?post=15775"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/npt-lok.com\/fa_ir\/wp-json\/wp\/v2\/tags?post=15775"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}