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<ul id="toc-Uses-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Specifications" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Specifications"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Specifications</span> </div> </a> <button aria-controls="toc-Specifications-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Specifications subsection</span> </button> <ul id="toc-Specifications-sublist" class="vector-toc-list"> <li id="toc-Thread_form" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Thread_form"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.1</span> <span>Thread form</span> </div> </a> <ul id="toc-Thread_form-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-National_pipe_taper_fuel_(NPTF)" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#National_pipe_taper_fuel_(NPTF)"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.2</span> <span>National pipe taper fuel (NPTF)</span> </div> </a> <ul id="toc-National_pipe_taper_fuel_(NPTF)-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Standard_sizes" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Standard_sizes"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Standard sizes</span> </div> </a> <ul id="toc-Standard_sizes-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-History" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#History"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>History</span> </div> </a> <ul id="toc-History-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Bibliography" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Bibliography"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>Bibliography</span> </div> </a> <ul id="toc-Bibliography-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" 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<figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Malefemalepipe.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b1/Malefemalepipe.jpg/220px-Malefemalepipe.jpg" decoding="async" width="220" height="172" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/b/b1/Malefemalepipe.jpg 1.5x" data-file-width="228" data-file-height="178" /></a><figcaption>Threaded pipe and <a href="/wiki/Piping_and_plumbing_fittings#Elbow" class="mw-redirect" title="Piping and plumbing fittings">elbow</a>. The pipe has a <a href="/wiki/Gender_of_connectors_and_fasteners" title="Gender of connectors and fasteners">male</a> NPT thread, while the elbow is <a href="/wiki/Gender_of_connectors_and_fasteners" title="Gender of connectors and fasteners">female</a>.</figcaption></figure> <p><b>American National Standard Pipe Thread</b> standards, often called <b>national pipe thread</b> standards for short, are United States national <a href="/wiki/Technical_standard" title="Technical standard">technical standards</a> for <a href="/wiki/Screw_thread" title="Screw thread">screw threads</a> used on <a href="/wiki/Threaded_pipe" title="Threaded pipe">threaded pipes</a> and <a href="/wiki/Piping_and_plumbing_fitting" title="Piping and plumbing fitting">pipe fittings</a>. They include both <a href="/wiki/Screw_thread#Taper" title="Screw thread">tapered</a> and straight thread series for various purposes, including rigidity, <a href="/wiki/Pressure" title="Pressure">pressure</a>-tight sealing, or both.<sup id="cite_ref-FOOTNOTEMachinery's_Handbook19961772–1781_1-0" class="reference"><a href="#cite_note-FOOTNOTEMachinery's_Handbook19961772–1781-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> The types are named with a full name and an abbreviation, such as <b>NPT</b>, <b>NPS</b>, <b>NPTF</b>, or <b>NPSC</b>. </p><p><b>MIP</b> is an abbreviation for male iron pipe, and <b>FIP</b> is an abbreviation for female iron pipe.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p><p>Outside North America, some US pipe thread sizes are widely used, as well as many <a href="/wiki/British_Standard_Pipe" title="British Standard Pipe">British Standard Pipe</a> threads and <a href="/wiki/International_Organization_for_Standardization" title="International Organization for Standardization">ISO</a> 7–1, 7–2, 228–1, and 228-2 threads. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Types">Types</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=National_pipe_thread&action=edit&section=1" title="Edit section: Types"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The various types are each named with an abbreviation and a full name, as follows:<sup id="cite_ref-FOOTNOTEMachinery's_Handbook19961776–1778_3-0" class="reference"><a href="#cite_note-FOOTNOTEMachinery's_Handbook19961776–1778-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p> <table class="wikitable sortable" border="1"> <tbody><tr> <th scope="col" style="width: 16%;">Abbreviation<sup id="cite_ref-FOOTNOTEMachinery's_Handbook19961776–1778_3-1" class="reference"><a href="#cite_note-FOOTNOTEMachinery's_Handbook19961776–1778-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </th> <th scope="col" style="width: 25%;">Shorthand expansion </th> <th scope="col" style="width: 24%;">Full name<sup id="cite_ref-FOOTNOTEMachinery's_Handbook19961776–1778_3-2" class="reference"><a href="#cite_note-FOOTNOTEMachinery's_Handbook19961776–1778-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </th> <th scope="col" style="width: 35%;">Comment<sup id="cite_ref-FOOTNOTEMachinery's_Handbook19961776–1778_3-3" class="reference"><a href="#cite_note-FOOTNOTEMachinery's_Handbook19961776–1778-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </th></tr> <tr> <td>NPT</td> <td>National pipe taper</td> <td>American National Standard Taper Pipe Thread</td> <td>Tapered and needs thread sealant; for connections in nearly every type of service </td></tr> <tr> <td>NPS</td> <td>National pipe straight</td> <td>American National Standard Straight Pipe Thread</td> <td>For rigidity; sealable with o-ring or gasket; sometimes male straight is mated with female tapered for low-pressure sealing (need to verify) </td></tr> <tr> <td>NPSC</td> <td>National pipe straight–coupling</td> <td>American National Standard Straight Pipe Thread for Couplings</td> <td>For general <a href="/wiki/Coupling" title="Coupling">couplings</a> </td></tr> <tr> <td>NPSF</td> <td>National pipe straight–fuel and oil</td> <td>Dryseal USA (American) Standard Fuel Internal Straight Pipe Thread</td> <td>Internal only, straight </td></tr> <tr> <td>NPSH</td> <td>National pipe straight–hose</td> <td>American National Standard Straight Pipe Thread for Hose Couplings</td> <td>For <a href="/wiki/Hose_coupling" title="Hose coupling">hose couplings</a> </td></tr> <tr> <td>NPSI</td> <td>National pipe straight–intermediate</td> <td>Dryseal USA (American) Standard Intermediate Internal Straight Pipe Thread</td> <td>Similar to NPSF but slightly larger; internal only, straight </td></tr> <tr> <td>NPSL</td> <td>National pipe straight–locknut</td> <td>American National Standard Straight Pipe Thread for Loose-fitting Mechanical Joints with Locknuts</td> <td>For use with <a href="/wiki/Locknut" title="Locknut">locknuts</a> </td></tr> <tr> <td>NPSM</td> <td>National pipe straight–mechanical</td> <td>American National Standard Straight Pipe Thread for Free-fitting Mechanical Joints</td> <td>For various rigid mechanical uses </td></tr> <tr> <td>NPTF</td> <td>National pipe taper–fuel and oil</td> <td>Dryseal USA (American) Standard Taper Pipe Thread</td> <td>For dryseal connections in nearly every type of service, especially <a href="/wiki/Fuel" title="Fuel">fuel</a> connections </td></tr> <tr> <td>NPTR</td> <td>National pipe taper–railing</td> <td>American National Standard Taper Pipe Thread for Railing Joints</td> <td>For <a href="/wiki/Handrail" title="Handrail">railings</a> </td></tr> <tr> <td>PTF-SAE SHORT</td> <td>Pipe taper, fuel, SAE, short</td> <td>Dryseal SAE Short Taper Pipe Thread</td> <td>Named after <a href="/wiki/SAE_International" title="SAE International">SAE International</a>; similar to NPTF but one turn shorter </td></tr></tbody></table> <div class="mw-heading mw-heading2"><h2 id="Uses">Uses</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=National_pipe_thread&action=edit&section=2" title="Edit section: Uses"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Threaded pipes can provide an effective seal for pipes transporting <a href="/wiki/Liquids" class="mw-redirect" title="Liquids">liquids</a>, <a href="/wiki/Gases" class="mw-redirect" title="Gases">gases</a>, <a href="/wiki/Steam" title="Steam">steam</a>, and <a href="/wiki/Hydraulic" class="mw-redirect" title="Hydraulic">hydraulic</a> fluid. These threads are now used in materials other than steel and brass, including <a href="/wiki/Polytetrafluoroethylene" title="Polytetrafluoroethylene">PTFE</a>, <a href="/wiki/Polyvinyl_chloride" title="Polyvinyl chloride">PVC</a>, <a href="/wiki/Nylon" title="Nylon">nylon</a>, <a href="/wiki/Bronze" title="Bronze">bronze</a>, and <a href="/wiki/Cast_iron" title="Cast iron">cast iron</a>. </p><p>The taper on NPT threads allows them to form a seal when torqued as the flanks of the threads compress against each other, as opposed to parallel/straight thread fittings or <a href="/wiki/Compression_fitting" title="Compression fitting">compression fittings</a> in which the threads merely hold the pieces together and do not provide a seal. The various types of pipe threads are designed for use both with or without thread sealants,<sup id="cite_ref-FOOTNOTEMachinery's_Handbook19961772–1781_1-1" class="reference"><a href="#cite_note-FOOTNOTEMachinery's_Handbook19961772–1781-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> as particular applications demand. The sealants, where used, are typically <a href="/wiki/Thread_seal_tape" title="Thread seal tape">thread seal tape</a> thread sealant or a thread seal paste <a href="/wiki/Pipe_dope" title="Pipe dope">pipe dope</a> (sometimes similar in composition to <a href="/wiki/Plumber%27s_putty" class="mw-redirect" title="Plumber's putty">plumber's putty</a>). </p><p>Because the thread body is tapered (0.75 in/ft or 62.5 mm/m), a larger diameter keeps compressing into a smaller diameter and finally forms a seal (no clearance remains between the crests and roots of the threads because of the taper). This means that NPT fittings should be <a href="/wiki/Burr_(edge)" title="Burr (edge)">burr</a>-free and lubricated using a <a href="/wiki/Lubricant" title="Lubricant">lubricant</a> like lubricating paste or thread seal tape. The use of tape also helps to limit corrosion on the threads, which otherwise can make future disassembly nearly impossible. </p><p>Commonly used sizes are <style data-mw-deduplicate="TemplateStyles:r1154941027">.mw-parser-output .frac{white-space:nowrap}.mw-parser-output .frac .num,.mw-parser-output .frac .den{font-size:80%;line-height:0;vertical-align:super}.mw-parser-output .frac .den{vertical-align:sub}.mw-parser-output .sr-only{border:0;clip:rect(0,0,0,0);clip-path:polygon(0px 0px,0px 0px,0px 0px);height:1px;margin:-1px;overflow:hidden;padding:0;position:absolute;width:1px}</style><span class="frac"><span class="num">1</span>⁄<span class="den">8</span></span>, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac"><span class="num">1</span>⁄<span class="den">4</span></span>, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac"><span class="num">3</span>⁄<span class="den">8</span></span>, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac"><span class="num">1</span>⁄<span class="den">2</span></span>, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac"><span class="num">3</span>⁄<span class="den">4</span></span>, 1, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac">1<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">4</span></span>, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac">1<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">2</span></span>, 2, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac">2<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">2</span></span>, 3, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac">3<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">2</span></span>, 4, 5, and 6 inch, as <a href="/wiki/Pipe_(material)" class="mw-redirect" title="Pipe (material)">pipe</a> and fittings by most US suppliers. Sizes smaller than <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac"><span class="num">1</span>⁄<span class="den">8</span></span> inch are occasionally used for compressed air, while sizes larger than 6 inches are often joined by other methods. </p> <div class="mw-heading mw-heading2"><h2 id="Specifications">Specifications</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=National_pipe_thread&action=edit&section=3" title="Edit section: Specifications"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>NPT is defined by <a href="/wiki/ANSI" class="mw-redirect" title="ANSI">ANSI</a>/<a href="/wiki/American_Society_of_Mechanical_Engineers" title="American Society of Mechanical Engineers">ASME</a> standard B1.20.1.<sup id="cite_ref-B1.20.1_4-0" class="reference"><a href="#cite_note-B1.20.1-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p><p>The taper rate for all NPT threads is 1 inch of diameter in 16 inches of length (<link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac"><span class="num">3</span>⁄<span class="den">4</span></span> inch per foot or 62.5 millimeters per meter) measured by the change of diameter (of the pipe thread) over distance of thread. The half-angle (between the taper surface and the axis of the pipe) is <a href="/wiki/Inverse_tangent" class="mw-redirect" title="Inverse tangent">arctan</a>(<link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac"><span class="num">1</span>⁄<span class="den">32</span></span>) ≈ 1.7899° ≈ 1° 47′. </p><p>The standard for <a href="/wiki/Nominal_Pipe_Size" title="Nominal Pipe Size">Nominal Pipe Size</a> (often abbreviated NPS, which should not be confused with the abbreviation NPS for the straight thread form standard) is loosely related to the inside diameter of <a href="/wiki/Schedule_40" class="mw-redirect" title="Schedule 40">Schedule 40</a> series of sizes. Because of the pipe wall thickness of Schedule pipe, the actual diameter of the NPT threads is larger than the Nominal Pipe Size diameter, and considerably so for small sizes. Pipe of a given size in a different Schedule than Schedule 40 provides a different wall thickness while maintaining the same outside diameter and thread profile as Schedule 40. Thus the inside diameter of a given size of Schedule pipe differs from the Nominal Pipe Size, while outside diameters for a given nominal Schedule size are the same between Schedules. </p> <div class="mw-heading mw-heading3"><h3 id="Thread_form">Thread form</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=National_pipe_thread&action=edit&section=4" title="Edit section: Thread form"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>National Pipe Thread series have the same 60° included angle as <a href="/wiki/Screw_thread#History_of_standardization" title="Screw thread">Sellers thread</a>. On the other hand, for sealing capability, tapered (pressure-tight) threads have crest and root shapes that differ from Sellers. For example, the NPT has a crest width of 0.038 to 0.062 pitch, which is sharper than the 0.125 pitch of Sellers. <sup id="cite_ref-B1.20.1_4-1" class="reference"><a href="#cite_note-B1.20.1-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="National_pipe_taper_fuel_(NPTF)"><span id="National_pipe_taper_fuel_.28NPTF.29"></span>National pipe taper fuel (NPTF)</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=National_pipe_thread&action=edit&section=5" title="Edit section: National pipe taper fuel (NPTF)"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p><b>National Pipe Taper Fuel</b> (<b>NPTF</b>, also called <b>Dryseal American National Standard Taper Pipe Thread</b>, defined by ASME B1.20.3) is designed to provide a more leak-free seal without the use of <a href="/wiki/Polytetrafluoroethylene" title="Polytetrafluoroethylene">PTFE</a> tape (often referred to by the popular brand name "Teflon") or another sealant compound. NPTF threads have the same basic shape but with crest and root heights adjusted for an interference fit, eliminating the spiral leakage path. </p> <div class="mw-heading mw-heading2"><h2 id="Standard_sizes">Standard sizes</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=National_pipe_thread&action=edit&section=6" title="Edit section: Standard sizes"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <table class="wikitable" style="text-align:center"> <caption>American Society of Mechanical Engineers National Pipe Thread Taper (NPT)<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </caption> <tbody><tr> <th rowspan="2"><a href="/wiki/Nominal_size" class="mw-redirect" title="Nominal size">Nominal</a> <br />pipe size </th> <th rowspan="2"><a href="/wiki/Screw_thread#Lead,_pitch,_and_starts" title="Screw thread">Thread <br />density</a> </th> <th colspan="2" rowspan="2"><a href="/wiki/Lead_(engineering)" title="Lead (engineering)">Thread pitch P</a> </th> <th colspan="3">Hand-tight engagement<sup id="cite_ref-piping-designer_6-0" class="reference"><a href="#cite_note-piping-designer-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> </th> <th colspan="3">Effective thread<sup id="cite_ref-piping-designer_6-1" class="reference"><a href="#cite_note-piping-designer-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> </th> <th rowspan="2">Overall <br />length L<sub>4</sub><sup id="cite_ref-piping-designer_6-2" class="reference"><a href="#cite_note-piping-designer-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> </th> <th colspan="2" rowspan="2"><a href="/wiki/Real_versus_nominal_value#Engineering" title="Real versus nominal value">Actual</a> outside <br />diameter D </th> <th colspan="2" rowspan="2"><a href="/wiki/List_of_drill_and_tap_sizes" title="List of drill and tap sizes">Tap drill</a> </th></tr> <tr> <th>Length L<sub>1</sub> </th> <th>Turns </th> <th>Diameter E<sub>1</sub> </th> <th>Length L<sub>2</sub> </th> <th>Turns </th> <th>Diameter E<sub>2</sub> </th></tr> <tr> <th>inch </th> <th>inch<sup>−1</sup> </th> <th>inch</th> <th>mm </th> <th>inch </th> <th> </th> <th>inch </th> <th>inch </th> <th> </th> <th>inch </th> <th>inch </th> <th>inch</th> <th>mm </th> <th>inch</th> <th>mm </th></tr> <tr> <td><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac"><span class="num">1</span>⁄<span class="den">16</span></span> </td> <td>27 </td> <td style="text-align:right;">0.03703704 </td> <td style="text-align:right;">0.9407 </td> <td>0.1600</td> <td>4.32</td> <td>0.28118 </td> <td>0.2611</td> <td>7.05</td> <td>0.2875 </td> <td>0.3896 </td> <td style="text-align:right;">0.313 </td> <td style="text-align:right;">7.950 </td> <td></td> <td> </td></tr> <tr> <td><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac"><span class="num">1</span>⁄<span class="den">8</span></span></td> <td>27 </td> <td style="text-align:right;">0.03703704 </td> <td style="text-align:right;">0.9407 </td> <td>0.1615</td> <td>4.36</td> <td>0.37360 </td> <td>0.2639</td> <td>7.13</td> <td>0.38000 </td> <td>0.3924 </td> <td style="text-align:right;">0.405 </td> <td style="text-align:right;">10.287 </td> <td style="text-align:right;">0.339 </td> <td style="text-align:right;">8.6106 </td></tr> <tr> <td><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac"><span class="num">1</span>⁄<span class="den">4</span></span> </td> <td>18 </td> <td style="text-align:right;">0.05555555 </td> <td style="text-align:right;">1.4111 </td> <td>0.2278</td> <td>4.10</td> <td>0.49163 </td> <td>0.4018</td> <td>7.23</td> <td>0.50250 </td> <td>0.5946 </td> <td style="text-align:right;">0.540 </td> <td style="text-align:right;">13.716 </td> <td style="text-align:right;"><span class="frac"><span class="num">7</span>⁄<span class="den">16</span></span> </td> <td style="text-align:right;">11.113 </td></tr> <tr> <td><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac"><span class="num">3</span>⁄<span class="den">8</span></span> </td> <td>18 </td> <td style="text-align:right;">0.05555555 </td> <td style="text-align:right;">1.4111 </td> <td>0.2400</td> <td>4.32</td> <td>0.62701 </td> <td>0.4078</td> <td>7.34</td> <td>0.63750 </td> <td>0.6006 </td> <td style="text-align:right;">0.675 </td> <td style="text-align:right;">17.145 </td> <td style="text-align:right;"><span class="frac"><span class="num">37</span>⁄<span class="den">64</span></span> </td> <td style="text-align:right;">14.684 </td></tr> <tr> <td><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac"><span class="num">1</span>⁄<span class="den">2</span></span> </td> <td>14 </td> <td style="text-align:right;">0.07142857 </td> <td style="text-align:right;">1.8143 </td> <td>0.3200</td> <td>4.48</td> <td>0.77843 </td> <td>0.5337</td> <td>7.47</td> <td>0.79178 </td> <td>0.7815 </td> <td style="text-align:right;">0.840 </td> <td style="text-align:right;">21.3360 </td> <td style="text-align:right;"><span class="frac"><span class="num">23</span>⁄<span class="den">32</span></span> </td> <td style="text-align:right;">18.2563 </td></tr> <tr> <td><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac"><span class="num">3</span>⁄<span class="den">4</span></span> </td> <td>14 </td> <td style="text-align:right;">0.07142857 </td> <td style="text-align:right;">1.8143 </td> <td>0.3390</td> <td>4.75</td> <td>0.98887 </td> <td>0.5457</td> <td>7.64</td> <td>1.00178 </td> <td>0.7935 </td> <td style="text-align:right;">1.050 </td> <td style="text-align:right;">26.6700 </td> <td style="text-align:right;"><span class="frac"><span class="num">59</span>⁄<span class="den">64</span></span> </td> <td style="text-align:right;">23.4156 </td></tr> <tr> <td>1 </td> <td><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac">11<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">2</span></span> </td> <td style="text-align:right;">0.08695652 </td> <td style="text-align:right;">2.2087 </td> <td>0.4000</td> <td>4.60</td> <td>1.23863 </td> <td>0.6828</td> <td>7.85</td> <td>1.25631 </td> <td>0.9845 </td> <td style="text-align:right;">1.315 </td> <td style="text-align:right;">33.4010 </td> <td style="text-align:right;"><span class="frac">1<span class="sr-only">+</span><span class="num">5</span>⁄<span class="den">32</span></span> </td> <td style="text-align:right;">29.3688 </td></tr> <tr> <td><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac">1<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">4</span></span> </td> <td><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac">11<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">2</span></span> </td> <td style="text-align:right;">0.08695652 </td> <td style="text-align:right;">2.2087 </td> <td>0.4200</td> <td>4.83</td> <td>1.58338 </td> <td>0.7068</td> <td>8.13</td> <td>1.60131 </td> <td>1.0085 </td> <td style="text-align:right;">1.660 </td> <td style="text-align:right;">42.1640 </td> <td style="text-align:right;"><span class="frac">1<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">2</span></span> </td> <td style="text-align:right;">38.1000 </td></tr> <tr> <td><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac">1<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">2</span></span> </td> <td><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac">11<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">2</span></span> </td> <td style="text-align:right;">0.08695652 </td> <td style="text-align:right;">2.2087 </td> <td>0.4200</td> <td>4.83</td> <td>1.82234 </td> <td>0.7235</td> <td>8.32</td> <td>1.84131 </td> <td>1.0252 </td> <td style="text-align:right;">1.900 </td> <td style="text-align:right;">48.2600 </td> <td style="text-align:right;"><span class="frac">1<span class="sr-only">+</span><span class="num">47</span>⁄<span class="den">64</span></span> </td> <td style="text-align:right;">44.0531 </td></tr> <tr> <td>2 </td> <td><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac">11<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">2</span></span> </td> <td style="text-align:right;">0.08695652 </td> <td style="text-align:right;">2.2087 </td> <td>0.4360</td> <td>5.01</td> <td>2.29627 </td> <td>0.7565</td> <td>8.70</td> <td>2.31630 </td> <td>1.0582 </td> <td style="text-align:right;">2.375 </td> <td style="text-align:right;">60.3250 </td> <td style="text-align:right;"><span class="frac">2<span class="sr-only">+</span><span class="num">7</span>⁄<span class="den">32</span></span> </td> <td style="text-align:right;">56.3563 </td></tr> <tr> <td><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac">2<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">2</span></span> </td> <td>8 </td> <td style="text-align:right;">0.12500000 </td> <td style="text-align:right;">3.1750 </td> <td>0.6820</td> <td>5.46</td> <td>2.76216 </td> <td>1.1375</td> <td>9.10</td> <td>2.79063 </td> <td>1.5712 </td> <td style="text-align:right;">2.875 </td> <td style="text-align:right;">73.0250 </td> <td style="text-align:right;"><span class="frac">2<span class="sr-only">+</span><span class="num">5</span>⁄<span class="den">8</span></span> </td> <td style="text-align:right;">66.6750 </td></tr> <tr> <td>3 </td> <td>8 </td> <td style="text-align:right;">0.12500000 </td> <td style="text-align:right;">3.1750 </td> <td>0.7660</td> <td>6.13</td> <td>3.38850 </td> <td>1.2000</td> <td>9.60</td> <td>3.41563 </td> <td>1.6337 </td> <td style="text-align:right;">3.500 </td> <td style="text-align:right;">88.9000 </td> <td style="text-align:right;"><span class="frac">3<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">4</span></span> </td> <td style="text-align:right;">82.5500 </td></tr> <tr> <td><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac">3<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">2</span></span> </td> <td>8 </td> <td style="text-align:right;">0.12500000 </td> <td style="text-align:right;">3.1750 </td> <td>0.8210</td> <td>6.57</td> <td>3.88881 </td> <td>1.2500</td> <td>10.00</td> <td>3.91563 </td> <td>1.6837 </td> <td style="text-align:right;">4.000 </td> <td style="text-align:right;">101.6000 </td> <td style="text-align:right;"><span class="frac">3<span class="sr-only">+</span><span class="num">3</span>⁄<span class="den">4</span></span> </td> <td style="text-align:right;">95.2500 </td></tr> <tr> <td>4 </td> <td>8 </td> <td style="text-align:right;">0.12500000 </td> <td style="text-align:right;">3.1750 </td> <td>0.8440</td> <td>6.75</td> <td>4.38713 </td> <td>1.3000</td> <td>10.40</td> <td>4.41563 </td> <td>1.7337 </td> <td style="text-align:right;">4.500 </td> <td style="text-align:right;">114.3000 </td> <td style="text-align:right;"><span class="frac">4<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">4</span></span> </td> <td style="text-align:right;">107.9500 </td></tr> <tr> <td><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac">4<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">2</span></span> </td> <td>8 </td> <td style="text-align:right;">0.12500000 </td> <td style="text-align:right;">3.1750 </td> <td></td> <td></td> <td> </td> <td></td> <td></td> <td> </td> <td> </td> <td style="text-align:right;">5.000 </td> <td style="text-align:right;">127.0000 </td> <td style="text-align:right;"><span class="frac">4<span class="sr-only">+</span><span class="num">3</span>⁄<span class="den">4</span></span> </td> <td style="text-align:right;">120.6500 </td></tr> <tr> <td>5 </td> <td>8 </td> <td style="text-align:right;">0.12500000 </td> <td style="text-align:right;">3.1750 </td> <td>0.9370</td> <td>7.50</td> <td>5.44929 </td> <td>1.4063</td> <td>11.25</td> <td>5.47863 </td> <td>1.8400 </td> <td style="text-align:right;">5.563 </td> <td style="text-align:right;">141.3002 </td> <td style="text-align:right;"><span class="frac">5<span class="sr-only">+</span><span class="num">9</span>⁄<span class="den">32</span></span> </td> <td style="text-align:right;">134.1438 </td></tr> <tr> <td>6 </td> <td>8 </td> <td style="text-align:right;">0.12500000 </td> <td style="text-align:right;">3.1750 </td> <td>0.9580</td> <td>7.66</td> <td>6.50597 </td> <td>1.5125</td> <td>12.10</td> <td>6.54063 </td> <td>1.9462 </td> <td style="text-align:right;">6.625 </td> <td style="text-align:right;">168.2750 </td> <td style="text-align:right;"><span class="frac">6<span class="sr-only">+</span><span class="num">11</span>⁄<span class="den">32</span></span> </td> <td style="text-align:right;">161.1313 </td></tr> <tr> <td>8 </td> <td>8 </td> <td style="text-align:right;">0.12500000 </td> <td style="text-align:right;">3.1750 </td> <td>1.0630</td> <td>8.50</td> <td>8.50003 </td> <td>1.7125</td> <td>13.70</td> <td>8.54063 </td> <td>2.1462 </td> <td style="text-align:right;">8.625 </td> <td style="text-align:right;">219.0750 </td> <td></td> <td> </td></tr> <tr> <td>10 </td> <td>8 </td> <td style="text-align:right;">0.12500000 </td> <td style="text-align:right;">3.1750 </td> <td>1.2100</td> <td>9.68</td> <td>10.62094 </td> <td>1.9250</td> <td>15.40</td> <td>10.66563 </td> <td>2.3587 </td> <td style="text-align:right;">10.750 </td> <td style="text-align:right;">273.0500 </td> <td></td> <td> </td></tr> <tr> <td>12 </td> <td>8 </td> <td style="text-align:right;">0.12500000 </td> <td style="text-align:right;">3.1750 </td> <td>1.3600</td> <td>10.88</td> <td>12.61781 </td> <td>2.1250</td> <td>17.00</td> <td>12.66563 </td> <td>2.5587 </td> <td style="text-align:right;">12.750 </td> <td style="text-align:right;">323.8500 </td> <td></td> <td> </td></tr> <tr> <td>14 </td> <td>8 </td> <td style="text-align:right;">0.12500000 </td> <td style="text-align:right;">3.1750 </td> <td>1.5620</td> <td>12.50</td> <td>13.87263 </td> <td>2.2500</td> <td>18.00</td> <td>13.91563 </td> <td>2.6837 </td> <td style="text-align:right;">14.000 </td> <td style="text-align:right;">355.6000 </td> <td></td> <td> </td></tr> <tr> <td>16 </td> <td>8 </td> <td style="text-align:right;">0.12500000 </td> <td style="text-align:right;">3.1750 </td> <td>1.8120</td> <td>14.50</td> <td>15.87575 </td> <td>2.4500</td> <td>19.60</td> <td>15.91563 </td> <td>2.8837 </td> <td style="text-align:right;">16.000 </td> <td style="text-align:right;">406.4000 </td> <td></td> <td> </td></tr> <tr> <td>18 </td> <td>8 </td> <td style="text-align:right;">0.12500000 </td> <td style="text-align:right;">3.1750 </td> <td>2.0000</td> <td>16.00</td> <td>17.87500 </td> <td>2.6500</td> <td>21.20</td> <td>17.91563 </td> <td>3.0837 </td> <td style="text-align:right;">18.000 </td> <td style="text-align:right;">457.2000 </td> <td></td> <td> </td></tr> <tr> <td>20 </td> <td>8 </td> <td style="text-align:right;">0.12500000 </td> <td style="text-align:right;">3.1750 </td> <td>2.1250</td> <td>17.00</td> <td>19.87031 </td> <td>2.8500</td> <td>22.80</td> <td>19.91563 </td> <td>3.2837 </td> <td style="text-align:right;">20.000 </td> <td style="text-align:right;">508.0000 </td> <td></td> <td> </td></tr> <tr> <td>24 </td> <td>8 </td> <td style="text-align:right;">0.12500000 </td> <td style="text-align:right;">3.1750 </td> <td>2.3750</td> <td>19.00</td> <td>23.86094 </td> <td>3.2500</td> <td>26.00</td> <td>23.91563 </td> <td>3.6837 </td> <td style="text-align:right;">24.000 </td> <td style="text-align:right;">609.6000 </td> <td></td> <td> </td></tr></tbody></table> <figure class="mw-halign-center" typeof="mw:File/Frame"><a href="/wiki/File:NPT_Dimensions.svg" class="mw-file-description"><img alt="A NPT dimensions" src="//upload.wikimedia.org/wikipedia/commons/thumb/f/fe/NPT_Dimensions.svg/511px-NPT_Dimensions.svg.png" decoding="async" width="511" height="270" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/fe/NPT_Dimensions.svg/767px-NPT_Dimensions.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/fe/NPT_Dimensions.svg/1022px-NPT_Dimensions.svg.png 2x" data-file-width="511" data-file-height="270" /></a><figcaption>Hand-tight and effective thread engagement lengths</figcaption></figure> <div class="mw-heading mw-heading2"><h2 id="History">History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=National_pipe_thread&action=edit&section=7" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Screw_thread#History_of_standardization" title="Screw thread">Screw thread § History of standardization</a></div> <p>In 1864, <a href="/wiki/William_Sellers" title="William Sellers">William Sellers</a>, then president of <a href="/wiki/Franklin_Institute" title="Franklin Institute">Franklin Institute</a>, presented a standard for nuts, bolts, and screws. Out of this effort came the first <a href="/wiki/United_States_Standard_thread" title="United States Standard thread">United States Standard threads</a>, including pipe threads.<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=National_pipe_thread&action=edit&section=8" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1184024115">.mw-parser-output .div-col{margin-top:0.3em;column-width:30em}.mw-parser-output .div-col-small{font-size:90%}.mw-parser-output .div-col-rules{column-rule:1px solid #aaa}.mw-parser-output .div-col dl,.mw-parser-output .div-col ol,.mw-parser-output .div-col ul{margin-top:0}.mw-parser-output .div-col li,.mw-parser-output .div-col dd{page-break-inside:avoid;break-inside:avoid-column}</style><div class="div-col"> <ul><li><a href="/wiki/AN_thread" title="AN thread">AN thread</a></li> <li><a href="/wiki/British_Standard_Pipe" title="British Standard Pipe">British Standard Pipe</a></li> <li><a href="/wiki/Fire_hose_thread" class="mw-redirect" title="Fire hose thread">Fire hose thread</a></li> <li><a href="/wiki/Garden_hose_thread" class="mw-redirect" title="Garden hose thread">Garden hose thread</a></li> <li><a href="/wiki/Gender_of_connectors_and_fasteners" title="Gender of connectors and fasteners">Gender of connectors and fasteners</a></li> <li><a href="/wiki/Panzergewinde" title="Panzergewinde">Panzergewinde</a></li> <li><a href="/wiki/Thread_angle" title="Thread angle">Thread angle</a></li> <li><a href="/wiki/Threaded_pipe" title="Threaded pipe">Threaded pipe</a></li></ul> </div> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=National_pipe_thread&action=edit&section=9" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-FOOTNOTEMachinery's_Handbook19961772–1781-1"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEMachinery's_Handbook19961772–1781_1-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEMachinery's_Handbook19961772–1781_1-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFMachinery's_Handbook1996">Machinery's Handbook (1996)</a>, pp. 1772–1781.</span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFCauldwell2006" class="citation book cs1">Cauldwell, Rex (2006). <i>Plumbing</i>. Newtown, CT: Taunton Press. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/1561588172" title="Special:BookSources/1561588172"><bdi>1561588172</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Plumbing&rft.place=Newtown%2C+CT&rft.pub=Taunton+Press&rft.date=2006&rft.isbn=1561588172&rft.aulast=Cauldwell&rft.aufirst=Rex&rfr_id=info%3Asid%2Fen.wikipedia.org%3ANational+pipe+thread" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEMachinery's_Handbook19961776–1778-3"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEMachinery's_Handbook19961776–1778_3-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEMachinery's_Handbook19961776–1778_3-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-FOOTNOTEMachinery's_Handbook19961776–1778_3-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-FOOTNOTEMachinery's_Handbook19961776–1778_3-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFMachinery's_Handbook1996">Machinery's Handbook (1996)</a>, pp. 1776–1778.</span> </li> <li id="cite_note-B1.20.1-4"><span class="mw-cite-backlink">^ <a href="#cite_ref-B1.20.1_4-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-B1.20.1_4-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20080514135011/http://www.hemcogages.com/ansi.htm">"ANSI Thread Series Designations"</a>. Archived from <a rel="nofollow" class="external text" href="http://www.hemcogages.com/ansi.htm">the original</a> on 2008-05-14<span class="reference-accessdate">. Retrieved <span class="nowrap">2008-04-27</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=ANSI+Thread+Series+Designations&rft_id=http%3A%2F%2Fwww.hemcogages.com%2Fansi.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3ANational+pipe+thread" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://www.engineeringtoolbox.com/npt-national-pipe-taper-threads-d_750.html">Engineering toolbox</a></span> </li> <li id="cite_note-piping-designer-6"><span class="mw-cite-backlink">^ <a href="#cite_ref-piping-designer_6-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-piping-designer_6-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-piping-designer_6-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.piping-designer.com/index.php/disciplines/mechanical/84-stationary-equipment/fastener/1156-national-pipe-thread?title=National_Pipe_Thread">"National Pipe Thread"</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=National+Pipe+Thread&rft_id=http%3A%2F%2Fwww.piping-designer.com%2Findex.php%2Fdisciplines%2Fmechanical%2F84-stationary-equipment%2Ffastener%2F1156-national-pipe-thread%3Ftitle%3DNational_Pipe_Thread&rfr_id=info%3Asid%2Fen.wikipedia.org%3ANational+pipe+thread" class="Z3988"></span></span> </li> <li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20160426084836/https://www.engineerily.com/1304161-bsp-and-npt-threads-detailed-explanation-differences.htm">"BSP and NPT threads - Detailed Explanation, Differences"</a>. Archived from <a rel="nofollow" class="external text" href="https://www.engineerily.com/1304161-bsp-and-npt-threads-detailed-explanation-differences.htm">the original</a> on 2016-04-26<span class="reference-accessdate">. Retrieved <span class="nowrap">2016-04-17</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=BSP+and+NPT+threads+-+Detailed+Explanation%2C+Differences&rft_id=https%3A%2F%2Fwww.engineerily.com%2F1304161-bsp-and-npt-threads-detailed-explanation-differences.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3ANational+pipe+thread" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="Bibliography">Bibliography</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=National_pipe_thread&action=edit&section=10" title="Edit section: Bibliography"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMachinery's_Handbook1996" class="citation cs2">Oberg, Erik; Jones, Franklin D.; Horton, Holbrook L.; Ryffel, Henry H. (1996), Green, Robert E.; McCauley, Christopher J. (eds.), <i><a href="/wiki/Machinery%27s_Handbook" title="Machinery's Handbook">Machinery's Handbook</a></i> (25th ed.), New York: <a href="/wiki/Industrial_Press" title="Industrial Press">Industrial Press</a>, <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-8311-2575-2" title="Special:BookSources/978-0-8311-2575-2"><bdi>978-0-8311-2575-2</bdi></a>, <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/473691581">473691581</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Machinery%27s+Handbook&rft.place=New+York&rft.edition=25th&rft.pub=Industrial+Press&rft.date=1996&rft_id=info%3Aoclcnum%2F473691581&rft.isbn=978-0-8311-2575-2&rft.aulast=Oberg&rft.aufirst=Erik&rft.au=Jones%2C+Franklin+D.&rft.au=Horton%2C+Holbrook+L.&rft.au=Ryffel%2C+Henry+H.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ANational+pipe+thread" class="Z3988"></span></li></ul> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=National_pipe_thread&action=edit&section=11" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="http://www.amesweb.info/Screws/NPT_National_Taper_Pipe_Threads.aspx">NPT Pipe Thread Dimensions</a></li> <li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20120721055029/http://www.asme.org/products/codes---standards/pipe-threads--general-purpose--inch">ASME B1.20.-1983 Pipe Threads, General Purpose, Inch </a></li> <li><a rel="nofollow" class="external text" href="https://www.threadspecification.com/npt/">NPT Taper Pipe Threads</a></li></ul>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=National_pipe_thread&oldid=1241504537">https://en.wikipedia.org/w/index.php?title=National_pipe_thread&oldid=1241504537</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Help:Category" title="Help:Category">Categories</a>: <ul><li><a href="/wiki/Category:Thread_standards" title="Category:Thread standards">Thread standards</a></li><li><a href="/wiki/Category:Piping" title="Category:Piping">Piping</a></li><li><a href="/wiki/Category:Plumbing" title="Category:Plumbing">Plumbing</a></li><li><a href="/wiki/Category:Standards_of_the_United_States" title="Category:Standards of the United States">Standards of the United States</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:Articles_with_short_description" title="Category:Articles with short description">Articles with short description</a></li><li><a href="/wiki/Category:Short_description_is_different_from_Wikidata" title="Category:Short description is different from Wikidata">Short description is different from Wikidata</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last edited on 21 August 2024, at 14:57<span class="anonymous-show"> (UTC)</span>.</li> <li id="footer-info-copyright">Text is available under the <a href="/wiki/Wikipedia:Text_of_the_Creative_Commons_Attribution-ShareAlike_4.0_International_License" title="Wikipedia:Text of the Creative Commons Attribution-ShareAlike 4.0 International License">Creative Commons Attribution-ShareAlike 4.0 License</a>; additional terms may apply. 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