{"id":15665,"date":"2026-08-21T09:54:42","date_gmt":"2026-08-21T09:54:42","guid":{"rendered":"https:\/\/npt-lok.com\/?p=15665"},"modified":"2026-08-21T09:56:16","modified_gmt":"2026-08-21T09:56:16","slug":"connect-and-seal-npt-threads","status":"publish","type":"post","link":"https:\/\/npt-lok.com\/ja\/connect-and-seal-npt-threads\/","title":{"rendered":"NPT\u30cd\u30b8\u306e\u63a5\u7d9a\u3068\u30b7\u30fc\u30eb\u65b9\u6cd5"},"content":{"rendered":"<p><span style=\"font-weight: 400;\">\u00a0<\/span><span style=\"font-weight: 400;\">NPT is the US standard for tapered pipe threads. The taper wedges the threads together when tightened \u2013 that&#8217;s the sealing mechanism.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">However, the thread crests and roots never fully mate. Those microscopic gaps form a spiral leak path. So tape or pipe dope isn&#8217;t optional \u2013 it&#8217;s required.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Here&#8217;s a straightforward guide that walks you through each step, from prep work to final tightening. Follow it and your connections will hold.<\/span><\/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\">\u76ee\u6b21<\/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=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">\u30c8\u30b0\u30eb<\/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\/ja\/connect-and-seal-npt-threads\/#Preparation_Before_Installation\" >Preparation Before Installation<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/npt-lok.com\/ja\/connect-and-seal-npt-threads\/#Thread_Sealants_Tape_vs_Pipe_Dope\" >Thread Sealants: Tape vs. Pipe Dope<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/npt-lok.com\/ja\/connect-and-seal-npt-threads\/#PTFE_Tape\" >PTFE Tape<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/npt-lok.com\/ja\/connect-and-seal-npt-threads\/#Pipe_Dope_Thread_Sealant\" >Pipe Dope (Thread Sealant)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/npt-lok.com\/ja\/connect-and-seal-npt-threads\/#How_to_Apply_PTFE_Tape\" >How to Apply PTFE Tape<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/npt-lok.com\/ja\/connect-and-seal-npt-threads\/#How_to_Connect_Tighten_NPT_Fittings\" >How to Connect &amp; Tighten NPT Fittings<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/npt-lok.com\/ja\/connect-and-seal-npt-threads\/#Step_1_Hand_Tighten\" >Step 1: Hand Tighten<\/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\/ja\/connect-and-seal-npt-threads\/#Step_2_Wrench_Tighten\" >Step 2: Wrench Tighten<\/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\/ja\/connect-and-seal-npt-threads\/#Step_3_Clocking_For_Elbows_and_Angle_Fittings\" >Step 3: Clocking (For Elbows and Angle Fittings)<\/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\/ja\/connect-and-seal-npt-threads\/#Common_Mistakes_to_Avoid\" >Common Mistakes to Avoid<\/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\/ja\/connect-and-seal-npt-threads\/#FAQ\" >\u3088\u304f\u3042\u308b\u8cea\u554f<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-12\" href=\"https:\/\/npt-lok.com\/ja\/connect-and-seal-npt-threads\/#Contact_Us\" >\u304a\u554f\u3044\u5408\u308f\u305b<\/a><\/li><\/ul><\/nav><\/div>\n<h2><span class=\"ez-toc-section\" id=\"Preparation_Before_Installation\"><\/span><span style=\"font-weight: 400;\">Preparation Before Installation<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><b>Inspect the Threads<\/b><\/p>\n<p><span style=\"font-weight: 400;\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-15667 aligncenter\" src=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/08\/Pipe-cut-and-deburred.png\" alt=\"Inspect the Threads\" width=\"314\" height=\"198\" srcset=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/08\/Pipe-cut-and-deburred.png 704w, https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/08\/Pipe-cut-and-deburred-18x12.png 18w\" sizes=\"auto, (max-width: 314px) 100vw, 314px\" \/>Inspect both the<\/span><a href=\"https:\/\/npt-lok.com\/ja\/male-thread-vs-female-thread\/\"><span style=\"font-weight: 400;\"> male and female threads<\/span><\/a><span style=\"font-weight: 400;\"> for nicks, burrs, damaged or deformed threads, corrosion, dirt, and old sealant. Do not install a fitting with visibly damaged or deformed threads.<\/span><\/p>\n<p><b>Clean the Threads<\/b><\/p>\n<p><span style=\"font-weight: 400;\">Then, clean the threads. Grab a clean rag or wire brush and wipe off any oil, grease, dust, or old sealant from the threads.\u00a0<\/span><\/p>\n<p><b>Dry Fit<\/b><\/p>\n<p><span style=\"font-weight: 400;\">Do a quick dry fit before you apply any sealant. Hand-tighten the male fitting into the female port and see how it feels. It should thread in smoothly \u2013 no wobble, no grinding, no forcing. It should also stop and bind part way in, not spin all the way to the bottom. If something feels off \u2013 too tight, too loose, or it&#8217;s catching at an angle \u2013 stop right there. Don&#8217;t force it. Double-check the thread size, the standard (<\/span><a href=\"https:\/\/npt-lok.com\/ja\/npt%e3%81%a8bsp%e3%81%ae%e3%81%ad%e3%81%98%e5%b1%b1%e3%81%ae%e6%af%94%e8%bc%83\/\"><span style=\"font-weight: 400;\">NPT\u5bfeBSP<\/span><\/a><span style=\"font-weight: 400;\">), and inspect both parts for damage. A dry fit that fails is a warning. Heed it and you save yourself a leak down the road.<\/span><\/p>\n<p><b>Confirm Thread Compatibility<\/b><\/p>\n<p><span style=\"font-weight: 400;\">Before you go any further, make sure you&#8217;re actually working with the same thread type on both ends. NPT and BSP\/ISO threads are different systems \u2013 they may look alike at a glance, but they are not interchangeable. Forcing them together won&#8217;t seal, and it&#8217;ll damage the threads.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Check the markings on the fittings, look up the specs, or use a thread gauge if you&#8217;re not sure. If there&#8217;s any doubt about the thread standard or size, stop and verify it. Don&#8217;t assume. Don&#8217;t guess. Verify it first, install it second. That one extra check can save you from a leak that&#8217;s expensive to fix.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Thread_Sealants_Tape_vs_Pipe_Dope\"><\/span><span style=\"font-weight: 400;\">Thread Sealants: Tape vs. Pipe Dope<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span style=\"font-weight: 400;\">PTFE tape and pipe dope both get the job done\u2014they fill those tiny spiral gaps in NPT threads so nothing leaks. But they work differently, and each one shines in different applications.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-15666\" src=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/08\/Tape-vs.-Pipe-Dope.png\" alt=\"Tape-vs.-Pipe-Dope\" width=\"855\" height=\"435\" srcset=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/08\/Tape-vs.-Pipe-Dope.png 855w, https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/08\/Tape-vs.-Pipe-Dope-768x391.png 768w, https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/08\/Tape-vs.-Pipe-Dope-18x9.png 18w\" sizes=\"auto, (max-width: 855px) 100vw, 855px\" \/><\/p>\n<h3><span class=\"ez-toc-section\" id=\"PTFE_Tape\"><\/span><span style=\"font-weight: 400;\">PTFE Tape<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400;\">PTFE thread seal tape is wrapped around the male threads. It&#8217;s clean and easy to apply, and it doesn&#8217;t need curing time before assembly. The downside? You have to apply it correctly. Too much tape and you&#8217;ll interfere with thread engagement. Too little and it won&#8217;t seal.<\/span><\/p>\n<h3><span class=\"ez-toc-section\" id=\"Pipe_Dope_Thread_Sealant\"><\/span><span style=\"font-weight: 400;\">Pipe Dope (Thread Sealant)<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Pipe dope is a liquid or paste you brush onto the male threads. It seals and lubricates at the same time \u2013 which helps prevent galling on stainless steel.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Some products handle extreme temperatures, high pressures, or harsh chemicals. Others don&#8217;t. Check the label for pressure, temperature, and chemical compatibility.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Cure time varies too \u2013 some dry fast, some don&#8217;t. Read the instructions and give it the time it needs before pressurizing.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"How_to_Apply_PTFE_Tape\"><\/span><span style=\"font-weight: 400;\">How to Apply PTFE Tape<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><b>Pick the right tape width<\/b><span style=\"font-weight: 400;\"> for the job. For 1\/8&#8243;, 1\/4&#8243;, and 3\/8&#8243; male NPT threads, use 1\/4-inch tape. For 1\/2&#8243; and up, go with 1\/2-inch tape.<\/span><\/p>\n<p><b>Start wrapping<\/b><span style=\"font-weight: 400;\"> from the second thread back from the opening. Leave the first thread bare \u2013 you don&#8217;t want tape hanging past the end where it can shred off and get into the system.<\/span><\/p>\n<p><b>Wrap clockwise<\/b><span style=\"font-weight: 400;\"> when you&#8217;re looking at the threaded end. This way the tape pulls into the threads as you tighten, instead of peeling off. Keep it taut as you go \u2013 loose tape bunches up and won&#8217;t seal. Overlap each wrap by about half the tape width so you get full coverage without gaps.<\/span><\/p>\n<p><b>How many wraps?<\/b><span style=\"font-weight: 400;\"> For most medium-to-thick tapes, 2 to 3 wraps is enough. If you&#8217;re using thinner hardware-store tape, go with 3 to 5. If the fitting binds too early when you hand-tighten, you&#8217;ve used too much \u2013 peel it off and start over.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">When you&#8217;re done, <\/span><b>tear the tape off <\/b><span style=\"font-weight: 400;\">cleanly and press the loose end flat against the threads so nothing sticks up.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"How_to_Connect_Tighten_NPT_Fittings\"><\/span><span style=\"font-weight: 400;\">How to Connect &amp; Tighten <\/span><a href=\"https:\/\/npt-lok.com\/ja\/%e8%a8%88%e8%a3%85%e7%94%a8%e3%83%91%e3%82%a4%e3%83%97%e7%b6%99%e6%89%8b\/npt%e7%b6%99%e6%89%8b\/\"><span style=\"font-weight: 400;\">NPT\u7d99\u624b<\/span><\/a><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<h3><span class=\"ez-toc-section\" id=\"Step_1_Hand_Tighten\"><\/span><span style=\"font-weight: 400;\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-15668 aligncenter\" src=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/08\/nut-and-ferrule-on-the-pipe.png\" alt=\"Exploded view, labeled from left to right: C (nut), D (ferrule), E (male threaded fitting), F (gasket), and female threaded port.\" width=\"500\" height=\"295\" \/>Step 1: Hand Tighten<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Screw the male fitting into the female port by hand until it can no longer be turned; this is the &#8220;hand-tight&#8221; position. Most NPT fittings can be screwed in by hand for 3 to 5 turns before reaching this point. If the number of turns differs significantly, the threads may be out of specification. Use the alignment mark made during the dry fit to verify that you have returned to the correct hand-tight position.<\/span><\/p>\n<p><b>Important: <\/b><span style=\"font-weight: 400;\">never screw it in all the way to the bottom. The fitting should not bottom out against the female port; if it does, there is a problem with the threads.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-15669\" src=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/08\/nut.png\" alt=\"Diagram showing hand-tightening vs. wrench-tightening\" width=\"390\" height=\"403\" srcset=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/08\/nut.png 521w, https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/08\/nut-12x12.png 12w\" sizes=\"auto, (max-width: 390px) 100vw, 390px\" \/><\/p>\n<h3><span class=\"ez-toc-section\" id=\"Step_2_Wrench_Tighten\"><\/span><span style=\"font-weight: 400;\">Step 2: Wrench Tighten<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400;\">As a general guideline, tighten 1.5 to 3 turns past hand-tight for most NPT fittings under 1 inch. For larger sizes, follow the manufacturer\u2019s recommendations. ASME B1.20.1 suggests up to approximately 3 turns for many sizes, but actual practice often uses fewer turns.<\/span><\/p>\n<h3><span class=\"ez-toc-section\" id=\"Step_3_Clocking_For_Elbows_and_Angle_Fittings\"><\/span><span style=\"font-weight: 400;\">Step 3: Clocking (For Elbows and Angle Fittings)<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400;\">If you are installing an elbow or an angled fitting, the orientation of the opening is crucial. If the fitting aligns correctly before you have reached the recommended number of turns, keep turning\u2014do not stop early. If you have already turned past the alignment point, keep turning\u2014do not back it off. Never back off or loosen the fitting to adjust its orientation, as doing so will compromise the seal. Plan your starting position carefully to ensure the fitting ends up in the required orientation.\u00a0<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Common_Mistakes_to_Avoid\"><\/span><span style=\"font-weight: 400;\">Common Mistakes to Avoid<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span style=\"font-weight: 400;\">Even experienced installers make mistakes. Here are the most common pitfalls and how to avoid them.<\/span><\/p>\n<p><b>Wrapping Tape in the Wrong Direction: <\/b><span style=\"font-weight: 400;\">Winding counter-clockwise will cause the tape to loosen during tightening. It always winds clockwise. Check the direction before you start; it is easy to get it wrong.<\/span><\/p>\n<p><b>Using Too Much Tape: <\/b><span style=\"font-weight: 400;\">Excessive tape can interfere with proper thread engagement and potentially cause the female fitting to crack; furthermore, fragments of tape could enter the system and clog valves or filters. Refer to the recommended wrap count above: 2\u20133 wraps for thick tape, and up to 5 wraps for thin tape.<\/span><\/p>\n<p><b>Over-Tightening:<\/b><span style=\"font-weight: 400;\"> Overdo it with the wrench and you can crack the fitting, strip threads, or warp the connection. PTFE tape makes this easier because it lubricates\u2014turns feel so smooth you won&#8217;t notice until it&#8217;s too late. Follow the recommended turns for your size (usually 1.5 to 3 past hand-tight). If it still leaks, don&#8217;t just crank it more. Take it apart, clean it, and reseal properly.<\/span><\/p>\n<p><b>Under-Tightening:<\/b><span style=\"font-weight: 400;\"> Being too gentle can leave the threads loose. Tapered threads need to be driven in far enough to wedge together and actually seal. Follow the turn specs\u2014stopping short will just give you a slow drip.<\/span><\/p>\n<p><b>Not Cleaning Threads First:<\/b><span style=\"font-weight: 400;\"> Sealant won&#8217;t stick to dirty, oily, or rusty threads. It takes 30 seconds to clean them first, and it saves you a lot of trouble down the road.<\/span><\/p>\n<p><b>Covering the First Thread with Tape\/Sealant: <\/b><span style=\"font-weight: 400;\">If tape or dope hangs over the end of the fitting, pieces can break off and end up inside the system. Start wrapping at the first thread, but keep the tape flush with the fitting face or just behind it\u2014never let it go past the end.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"FAQ\"><\/span><span style=\"font-weight: 400;\">\u3088\u304f\u3042\u308b\u8cea\u554f<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><b>Q1. Can I use PTFE tape and pipe dope together?<\/b><\/p>\n<p><span style=\"font-weight: 400;\">Yeah, plenty of pros do it that way. Wrap with PTFE tape first, then brush a thin coat of pipe dope on top. The tape fills the bigger gaps; the dope seals the small ones. On high-pressure joints, using both gives you an extra layer of leak protection.<\/span><\/p>\n<p><b>Q2. What&#8217;s the difference between NPT and NPTF?<\/b><\/p>\n<p><span style=\"font-weight: 400;\">NPT always needs sealant. NPTF (Dryseal) is designed to seal dry, but if mixed with NPT, you still need sealant. Unless you&#8217;re sure the fittings are brand-new NPTF and perfect, use sealant.<\/span><\/p>\n<p><b>Q3. Why does my NPT fitting still leak after tightening?<\/b><\/p>\n<p><span style=\"font-weight: 400;\">Most leaks come down to one of these: dirty threads, using the wrong sealant, tape wrapped backwards, too many or too few wraps, not tight enough, overtightened and deformed threads, damaged threads, or mixing NPT with BSP.<\/span><\/p>\n<p><b>Q4. Can I reuse an NPT fitting?<\/b><\/p>\n<p><span style=\"font-weight: 400;\">Not really. Tightening deforms the threads each time. If you must reuse one, inspect carefully and apply fresh sealant. For critical systems, install new fittings\u2014it&#8217;s not worth the risk.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Contact_Us\"><\/span><a href=\"https:\/\/npt-lok.com\/ja\/%e8%a6%8b%e7%a9%8d%e3%82%82%e3%82%8a%e3%81%ab%e3%81%a4%e3%81%84%e3%81%a6%e3%81%af%e3%81%8a%e5%95%8f%e3%81%84%e5%90%88%e3%82%8f%e3%81%9b%e3%81%8f%e3%81%a0%e3%81%95%e3%81%84\/\"><span style=\"font-weight: 400;\">\u304a\u554f\u3044\u5408\u308f\u305b<\/span><\/a><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span style=\"font-weight: 400;\">If you\u2019re unsure which fitting or sealant to use, our engineers can help. NPT-LOK has been manufacturing <\/span><a href=\"https:\/\/npt-lok.com\/ja\/%e8%a8%88%e8%a3%85%e7%94%a8%e3%83%91%e3%82%a4%e3%83%97%e7%b6%99%e6%89%8b\/\"><span style=\"font-weight: 400;\">\u30d1\u30a4\u30d7\u7d99\u624b<\/span><\/a><span style=\"font-weight: 400;\"> 20\u5e74\u4ee5\u4e0a\u306b\u308f\u305f\u308a\u3001\u5b89\u5b9a\u3057\u305f\u9ad8\u54c1\u8cea\u306e\u30c1\u30e5\u30fc\u30d6\u7d99\u624b\u3092\u3054\u63d0\u4f9b\u3057\u3066\u307e\u3044\u308a\u307e\u3057\u305f\u3002\u591a\u304f\u306e\u304a\u5ba2\u69d8\u306b\u30c1\u30e5\u30fc\u30d6\u7d99\u624b\u3092\u7d0d\u5165\u3057\u3066\u304d\u305f\u5b9f\u7e3e\u304c\u3042\u308a\u3001\u8c4a\u5bcc\u306a\u30d7\u30ed\u30b8\u30a7\u30af\u30c8\u7d4c\u9a13\u3092\u6709\u3057\u3066\u3044\u307e\u3059\u3002\u304a\u5ba2\u69d8\u306e\u3054\u8981\u671b\u306b\u5fdc\u3058\u305f\u7279\u6ce8\u30c1\u30e5\u30fc\u30d6\u7d99\u624b\u3082\u88fd\u4f5c\u53ef\u80fd\u3067\u3059\u3002.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">For more details, feel free to download our <a href=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2024\/02\/Catalog-of-Pipe-Fittings-NPTLOK.pdf\">NPT Fittings Catalog<\/a>.\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">\u3082\u3063\u3068\u8a73\u3057\u304f\u77e5\u308b <\/span><a href=\"https:\/\/npt-lok.com\/ja\/%e7%a7%81%e3%81%9f%e3%81%a1%e3%81%ab%e3%81%a4%e3%81%84%e3%81%a6\/\"><span style=\"font-weight: 400;\">\u79c1\u305f\u3061\u306b\u3064\u3044\u3066<\/span><\/a><span style=\"font-weight: 400;\">.<\/span><\/p>","protected":false},"excerpt":{"rendered":"<p>\u00a0NPT is the US standard for tapered pipe threads. The taper wedges the threads together when tightened \u2013 that&#8217;s the sealing mechanism. However, the thread crests and roots never fully mate. Those microscopic gaps form a spiral leak path. So tape or pipe dope isn&#8217;t optional \u2013 it&#8217;s required. Here&#8217;s a straightforward guide that walks [&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-15665","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>How to Connect and Seal NPT Threads<\/title>\n<meta name=\"description\" content=\"NPT threads leaking again? 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