{"id":100173,"date":"2026-02-15T20:25:00","date_gmt":"2026-02-15T20:25:00","guid":{"rendered":"https:\/\/vibromera.eu\/?post_type=calculator&#038;p=100173"},"modified":"2026-02-15T20:25:00","modified_gmt":"2026-02-15T20:25:00","slug":"nut-strength-class-iso898","status":"publish","type":"calculator","link":"https:\/\/vibromera.eu\/bn\/calculators\/nut-strength-class-iso898\/","title":{"rendered":"Nut Strength Class ISO 898-2 Lookup | Free Online Tool"},"content":{"rendered":"\n<script type=\"application\/ld+json\">\n{\"@context\":\"https:\/\/schema.org\",\"@type\":\"WebApplication\",\"name\":\"Nut Strength Class ISO 898-2 Lookup\",\"alternateName\":[\"ISO 898-2 Nut Calculator\",\"Nut Grade Reference\"],\"description\":\"Free online reference tool for ISO 898-2 nut strength classes. Shows proof load stress, hardness, and matching bolt property class.\",\"url\":\"https:\/\/vibromera.eu\/calculators\/nut-strength-class-iso898\/\",\"applicationCategory\":\"Engineering Calculator\",\"operatingSystem\":\"Any (Web Browser)\",\"offers\":{\"@type\":\"Offer\",\"price\":\"0\",\"priceCurrency\":\"EUR\"},\"creator\":{\"@type\":\"Organization\",\"name\":\"Vibromera\",\"url\":\"https:\/\/vibromera.eu\/\"},\"datePublished\":\"2025-01-01\",\"dateModified\":\"2026-02-15\",\"inLanguage\":\"en\",\"isAccessibleForFree\":true,\"featureList\":[\"All ISO 898-2 nut classes\",\"Proof load stress values\",\"Hardness ranges HRC\/HV\",\"Matching bolt class\",\"Size-dependent proof loads\",\"Auto-calculation\"],\"keywords\":\"nut strength, ISO 898-2, proof load, hardness, bolt-nut matching\"}\n<\/script>\n\n<script type=\"application\/ld+json\">\n{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[\n{\"@type\":\"Question\",\"name\":\"What does nut strength class mean?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Nut strength class per ISO 898-2 indicates the proof load capability of the nut. It is designated by a single number (e.g., 8, 10, 12) that corresponds to 1\/100th of the minimum proof load stress in MPa for the reference bolt-nut combination.\"}},\n{\"@type\":\"Question\",\"name\":\"How do I match a nut to a bolt class?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"The nut class number should be equal to or greater than the first digit of the bolt class. For example: bolt 8.8 \u2192 nut class 8; bolt 10.9 \u2192 nut class 10; bolt 12.9 \u2192 nut class 12. This ensures the nut threads are at least as strong as the bolt.\"}},\n{\"@type\":\"Question\",\"name\":\"What is the proof load stress of a nut?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Proof load stress is the maximum axial stress a nut can sustain without permanent deformation, measured via a hardened mandrel test. For a class 8 nut (\u2264M16), this is 800 MPa. The actual proof load force depends on the bolt tensile stress area.\"}},\n{\"@type\":\"Question\",\"name\":\"Why are nut proof loads size-dependent?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Larger nuts (>M16) have reduced proof load stresses because the nut height to diameter ratio changes, thread engagement efficiency decreases, and load distribution across threads becomes less uniform at larger diameters.\"}},\n{\"@type\":\"Question\",\"name\":\"What hardness should a class 8 nut have?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"A class 8 nut per ISO 898-2 should have Vickers hardness HV 200\u2013302 (approximately Rockwell HRC 20\u201330). Nuts that are too hard may be brittle; too soft may strip threads under load.\"}}\n]}\n<\/script>\n\n<script type=\"application\/ld+json\">\n{\"@context\":\"https:\/\/schema.org\",\"@type\":\"BreadcrumbList\",\"itemListElement\":[\n{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/vibromera.eu\/\"},\n{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Calculators\",\"item\":\"https:\/\/vibromera.eu\/calculators\/\"},\n{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Nut Strength Class ISO 898-2\",\"item\":\"https:\/\/vibromera.eu\/calculators\/nut-strength-class-iso898\/\"}\n]}\n<\/script>\n\n<link rel=\"preconnect\" href=\"https:\/\/fonts.googleapis.com\">\n\n<link rel=\"preconnect\" href=\"https:\/\/fonts.gstatic.com\" crossorigin>\n\n<link 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.vc-faq-chevron{transform:rotate(180deg);}\n.vc-faq-a{max-height:0;overflow:hidden;transition:max-height 0.35s;}.vc-faq-item.vc-open .vc-faq-a{max-height:1200px;}\n.vc-faq-a-inner{padding:14px 16px;border-top:1px solid var(--vc-border-light);font-size:14px;color:var(--vc-ink-secondary);}.vc-faq-a-inner p{margin:0 0 8px;}.vc-faq-a-inner p:last-child{margin-bottom:0;}\n.vc-related{display:flex;flex-wrap:wrap;gap:10px;margin-top:16px;}.vc-related-link{display:inline-block;padding:8px 16px;font-family:var(--vc-font);font-size:13px;font-weight:600;background:var(--vc-surface-alt);color:var(--vc-ink-secondary);border:1px solid var(--vc-border);border-radius:var(--vc-radius);text-decoration:none;transition:all 0.15s;}.vc-related-link:hover{border-color:var(--vc-accent);color:var(--vc-accent);background:var(--vc-accent-light);}\n.vc-promo{margin-top:24px;padding:20px;background:linear-gradient(135deg,var(--vc-accent-light),var(--vc-surface));border:1px solid 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print{.vc-section-body{max-height:none!important;}.vc-faq-a{max-height:none!important;}.vc-results{max-height:none!important;padding:24px!important;}.vc-copy-btn,.vc-section-chevron,.vc-faq-chevron,.vc-presets,.vc-promo{display:none!important;}}\n<\/style>\n\n<div class=\"vc-calculator\" id=\"vc-nut-iso898\">\n\n<header class=\"vc-header\">\n    <p class=\"vc-header-eyebrow\">Free Engineering Tool<\/p>\n    <h1 class=\"vc-header-title\">Nut Strength Class \u2014 ISO 898-2<\/h1>\n    <p class=\"vc-header-subtitle\">Look up ISO 898-2 nut classes: proof load stress, hardness range, and matching bolt property class. Select nut class and size.<\/p>\n    <div class=\"vc-badges\"><span class=\"vc-badge\">ISO 898-2<\/span><span class=\"vc-badge\">Classes 5\u201312<\/span><span class=\"vc-badge\">M5 \u2013 M64<\/span><\/div>\n<\/header>\n\n<div class=\"vc-card\">\n    <form class=\"vc-form\" id=\"vc-form\" autocomplete=\"off\">\n        <div class=\"vc-form-grid\">\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-nutclass\">Nut Class<\/label>\n                <select class=\"vc-select\" id=\"vc-nutclass\">\n                    <option value=\"5\" data-sp-lo=\"500\" data-sp-hi=\"500\" data-hv-lo=\"130\" data-hv-hi=\"302\" data-bolt=\"4.6, 4.8, 5.6, 5.8\">Class 5<\/option>\n                    <option value=\"6\" data-sp-lo=\"600\" data-sp-hi=\"600\" data-hv-lo=\"150\" data-hv-hi=\"302\" data-bolt=\"6.8\">Class 6<\/option>\n                    <option value=\"8\" data-sp-lo=\"800\" data-sp-hi=\"800\" data-hv-lo=\"200\" data-hv-hi=\"302\" data-bolt=\"8.8\" selected>Class 8<\/option>\n                    <option value=\"10\" data-sp-lo=\"1040\" data-sp-hi=\"1040\" data-hv-lo=\"260\" data-hv-hi=\"353\" data-bolt=\"10.9\">Class 10<\/option>\n                    <option value=\"12\" data-sp-lo=\"1220\" data-sp-hi=\"1220\" data-hv-lo=\"295\" data-hv-hi=\"353\" data-bolt=\"12.9\">Class 12<\/option>\n                <\/select>\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-size\">Bolt\/Nut Size<\/label>\n                <select class=\"vc-select\" id=\"vc-size\">\n                    <option value=\"M5\" data-as=\"14.2\">M5<\/option>\n                    <option value=\"M6\" data-as=\"20.1\">M6<\/option>\n                    <option value=\"M8\" data-as=\"36.6\">M8<\/option>\n                    <option value=\"M10\" data-as=\"58.0\" selected>M10<\/option>\n                    <option value=\"M12\" data-as=\"84.3\">M12<\/option>\n                    <option value=\"M14\" data-as=\"115\">M14<\/option>\n                    <option value=\"M16\" data-as=\"157\">M16<\/option>\n                    <option value=\"M20\" data-as=\"245\">M20<\/option>\n                    <option value=\"M24\" data-as=\"353\">M24<\/option>\n                    <option value=\"M30\" data-as=\"561\">M30<\/option>\n                    <option value=\"M36\" data-as=\"817\">M36<\/option>\n                    <option value=\"M42\" data-as=\"1121\">M42<\/option>\n                    <option value=\"M48\" data-as=\"1473\">M48<\/option>\n                    <option value=\"M56\" data-as=\"2030\">M56<\/option>\n                    <option value=\"M64\" data-as=\"2676\">M64<\/option>\n                <\/select>\n            <\/div>\n        <\/div>\n        <div class=\"vc-presets\">\n            <div class=\"vc-presets-label\">Quick presets<\/div>\n            <button type=\"button\" class=\"vc-preset-btn\" data-cls=\"8\" data-sz=\"M10\">M10 Class 8<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-cls=\"10\" data-sz=\"M16\">M16 Class 10<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-cls=\"12\" data-sz=\"M20\">M20 Class 12<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-cls=\"8\" data-sz=\"M24\">M24 Class 8<\/button>\n        <\/div>\n    <\/form>\n\n    <div class=\"vc-results\" id=\"vc-results\">\n        <div class=\"vc-results-head\"><h2 class=\"vc-results-title\">Results<\/h2>\n            <button type=\"button\" class=\"vc-copy-btn\" id=\"vc-copy-btn\"><svg width=\"14\" height=\"14\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><rect x=\"9\" y=\"9\" width=\"13\" height=\"13\" rx=\"2\"\/><path d=\"M5 15H4a2 2 0 01-2-2V4a2 2 0 012-2h9a2 2 0 012 2v1\"\/><\/svg> Copy<\/button>\n        <\/div>\n        <div class=\"vc-result-grid\">\n            <div class=\"vc-rcard vc-rcard-primary\">\n                <div class=\"vc-rcard-label\">Proof Load Force<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-proof\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Proof Load Stress (Sp)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-sp\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Hardness Range (HV)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-hv\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Matching Bolt Class(es)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-bolt\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Tensile Stress Area (As)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-as\">\u2014<\/div>\n            <\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<div class=\"vc-section vc-open\" id=\"vc-sec-theory\">\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"true\"><span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">\ud83d\udcd8<\/span><span class=\"vc-section-title\">Theory &amp; Reference<\/span><\/span><svg class=\"vc-section-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button>\n    <div class=\"vc-section-body\">\n        <div class=\"vc-section-inner vc-theory\">\n            <h3>Proof Load<\/h3>\n            <p>The proof load of a nut is the maximum axial force it can withstand without permanent deformation:<\/p>\n            <div class=\"vc-formula-box\" id=\"vc-katex-1\"><\/div>\n            <h3>ISO 898-2 Nut Class Summary<\/h3>\n            <table class=\"vc-table\">\n                <thead><tr><th>Nut Class<\/th><th>Sp (MPa) \u2264M16<\/th><th>HV Range<\/th><th>Matching Bolt<\/th><\/tr><\/thead>\n                <tbody>\n                    <tr><td>5<\/td><td>500<\/td><td>130\u2013302<\/td><td>4.6, 4.8, 5.6, 5.8<\/td><\/tr>\n                    <tr><td>6<\/td><td>600<\/td><td>150\u2013302<\/td><td>6.8<\/td><\/tr>\n                    <tr><td>8<\/td><td>800<\/td><td>200\u2013302<\/td><td>8.8<\/td><\/tr>\n                    <tr><td>10<\/td><td>1040<\/td><td>260\u2013353<\/td><td>10.9<\/td><\/tr>\n                    <tr><td>12<\/td><td>1220<\/td><td>295\u2013353<\/td><td>12.9<\/td><\/tr>\n                <\/tbody>\n            <\/table>\n            <div class=\"vc-warning-box\"><p style=\"margin:0;font-size:14px;color:var(--vc-ink-secondary);\"><strong>\u26a0\ufe0f Note:<\/strong> For sizes >M16, proof load stresses are reduced per ISO 898-2 Table 2. Always check the standard for the actual size-dependent values.<\/p><\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<div class=\"vc-section\" id=\"vc-sec-related\">\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">\ud83d\udd17<\/span><span class=\"vc-section-title\">Related Calculators<\/span><\/span><svg class=\"vc-section-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button>\n    <div class=\"vc-section-body\"><div class=\"vc-section-inner\"><div class=\"vc-related\">\n        <a class=\"vc-related-link\" href=\"\/calculators\/bolt-strength-calculator\/\">Bolt Strength<\/a>\n        <a class=\"vc-related-link\" href=\"\/calculators\/bolt-preload-calculator\/\">Bolt Preload<\/a>\n        <a class=\"vc-related-link\" href=\"\/calculators\/bolt-dimensions-weight\/\">Bolt Dimensions<\/a>\n        <a class=\"vc-related-link\" href=\"\/calculators\/washer-selection\/\">Washer Selection<\/a>\n    <\/div><\/div><\/div>\n<\/div>\n\n<div class=\"vc-section\" id=\"vc-sec-faq\">\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">\u2753<\/span><span class=\"vc-section-title\">Frequently Asked Questions<\/span><\/span><svg class=\"vc-section-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button>\n    <div class=\"vc-section-body\"><div class=\"vc-section-inner\"><div class=\"vc-faq-list\" id=\"vc-faq-list\"><\/div><\/div><\/div>\n<\/div>\n\n<div class=\"vc-promo\"><div class=\"vc-promo-text\"><strong>Vibromera \u2014 Portable Balancing &amp; Vibration Analysis<\/strong><br>Professional instruments. Used in 50+ countries.<\/div><a class=\"vc-promo-link\" href=\"https:\/\/vibromera.eu\/\" target=\"_blank\" rel=\"noopener\">Learn More<\/a><\/div>\n<footer class=\"vc-footer\"><p>\u00a9 2024\u20132026 <a href=\"https:\/\/vibromera.eu\/\">Vibromera<\/a> \u2014 Engineering Calculators<\/p><p style=\"font-size:12px;margin-top:4px;\">Based on ISO 898-2. Last updated: February 2026<\/p><div class=\"vc-footer-links\"><a href=\"\/calculators\/engineering-calculators\/\">All Calculators<\/a><a href=\"https:\/\/vibromera.eu\/contacts\/\">Contact<\/a><\/div><\/footer>\n<\/div>\n\n<script src=\"https:\/\/cdn.jsdelivr.net\/npm\/katex@0.16.11\/dist\/katex.min.js\"><\/script>\n<script>\n(function(){\n    'use strict';\n    function $(id){return document.getElementById(id);}\n    function fmt(n,d){if(isNaN(n)||!isFinite(n))return '\u2014';var f=n.toFixed(d===undefined?2:d);return f.replace(\/(\\.\\d*?)0+$\/,'$1').replace(\/\\.$\/,'');}\n\n    function calculate(){\n        var cOpt=$('vc-nutclass').selectedOptions[0];\n        var sOpt=$('vc-size').selectedOptions[0];\n        var Sp=parseFloat(cOpt.getAttribute('data-sp-lo'));\n        var hvLo=cOpt.getAttribute('data-hv-lo'), hvHi=cOpt.getAttribute('data-hv-hi');\n        var bolt=cOpt.getAttribute('data-bolt');\n        var As=parseFloat(sOpt.getAttribute('data-as'));\n        \/\/ Reduce Sp for >M16\n        var d=parseFloat(sOpt.value.replace('M',''));\n        var spAdj=Sp;\n        if(d>16&&d<=39) spAdj=Sp*0.94;\n        else if(d>39) spAdj=Sp*0.90;\n        var Fp=spAdj*As;\n        $('vc-r-proof').innerHTML=fmt(Fp\/1000,1)+' <span class=\"vc-rcard-unit\">kN<\/span> <span class=\"vc-rcard-unit\">('+fmt(Fp,0)+' N)<\/span>';\n        $('vc-r-sp').innerHTML=fmt(spAdj,0)+' <span class=\"vc-rcard-unit\">MPa<\/span>'+(d>16?' <span class=\"vc-rcard-unit\">(reduced)<\/span>':'');\n        $('vc-r-hv').innerHTML=hvLo+' \u2013 '+hvHi+' <span class=\"vc-rcard-unit\">HV<\/span>';\n        $('vc-r-bolt').innerHTML=bolt;\n        $('vc-r-as').innerHTML=fmt(As,1)+' <span class=\"vc-rcard-unit\">mm\u00b2<\/span>';\n        $('vc-results').classList.add('vc-visible');\n    }\n\n    document.querySelectorAll('.vc-preset-btn').forEach(function(btn){btn.addEventListener('click',function(e){e.preventDefault();$('vc-nutclass').value=this.getAttribute('data-cls');$('vc-size').value=this.getAttribute('data-sz');calculate();});});\n    $('vc-form').addEventListener('input',calculate);$('vc-form').addEventListener('change',calculate);\n\n    $('vc-copy-btn').addEventListener('click',function(){var text='Nut Class Lookup\\n\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\\nClass: '+$('vc-nutclass').value+', Size: '+$('vc-size').value+'\\nProof Load: '+$('vc-r-proof').textContent+'\\nSp: '+$('vc-r-sp').textContent+'\\nHardness: '+$('vc-r-hv').textContent+'\\nMatching bolt: '+$('vc-r-bolt').textContent+'\\n\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\\nvibromera.eu';if(navigator.clipboard){navigator.clipboard.writeText(text).then(function(){var b=$('vc-copy-btn');b.classList.add('vc-copied');b.innerHTML='<svg width=\"14\" height=\"14\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><polyline points=\"20 6 9 17 4 12\"\/><\/svg> Copied!';setTimeout(function(){b.classList.remove('vc-copied');b.innerHTML='<svg width=\"14\" height=\"14\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><rect x=\"9\" y=\"9\" width=\"13\" height=\"13\" rx=\"2\"\/><path d=\"M5 15H4a2 2 0 01-2-2V4a2 2 0 012-2h9a2 2 0 012 2v1\"\/><\/svg> Copy';},2000);});}});\n\n    document.querySelectorAll('.vc-section-toggle').forEach(function(btn){btn.addEventListener('click',function(){var s=this.closest('.vc-section');s.classList.toggle('vc-open');this.setAttribute('aria-expanded',s.classList.contains('vc-open'));});});\n\n    var faqData=[\n        {q:'What does nut strength class mean?',a:'<p>Nut strength class per ISO 898-2 indicates the proof load capability. The number equals 1\/100th of the minimum proof load stress in MPa for the standard bolt-nut combination.<\/p>'},\n        {q:'How do I match a nut to a bolt class?',a:'<p>The nut class should equal or exceed the first digit of the bolt class: bolt 8.8 \u2192 nut 8; bolt 10.9 \u2192 nut 10; bolt 12.9 \u2192 nut 12.<\/p>'},\n        {q:'What is the proof load stress of a nut?',a:'<p>Proof load stress is the maximum axial stress without permanent deformation. For class 8 (\u2264M16): 800 MPa. Actual proof load force = Sp \u00d7 As.<\/p>'},\n        {q:'Why are nut proof loads size-dependent?',a:'<p>Larger nuts (>M16) have reduced proof load stresses because the height-to-diameter ratio changes and thread engagement efficiency decreases at larger diameters.<\/p>'},\n        {q:'What hardness should a class 8 nut have?',a:'<p>Class 8: HV 200\u2013302. Too hard = brittle risk; too soft = thread stripping risk. Always within the ISO 898-2 specified range.<\/p>'}\n    ];\n    var fl=$('vc-faq-list');faqData.forEach(function(f){fl.innerHTML+='<div class=\"vc-faq-item\"><button type=\"button\" class=\"vc-faq-q\"><span>'+f.q+'<\/span><svg class=\"vc-faq-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button><div class=\"vc-faq-a\"><div class=\"vc-faq-a-inner\">'+f.a+'<\/div><\/div><\/div>';});\n    fl.addEventListener('click',function(e){var b=e.target.closest('.vc-faq-q');if(b)b.closest('.vc-faq-item').classList.toggle('vc-open');});\n\n    function renderFormulas(){try{katex.render('F_p = S_p \\\\times A_s \\\\quad [\\\\text{N}]',$('vc-katex-1'),{displayMode:true,throwOnError:false});}catch(e){}}\n    function init(){renderFormulas();calculate();}\n    if(document.readyState==='loading'){document.addEventListener('DOMContentLoaded',init);}else{init();}\n})();\n<\/script>\n","protected":false},"excerpt":{"rendered":"<p>Free online ISO 898-2 nut strength class reference. Enter nut class to see proof load stress, hardness ranges, and matching bolt property class.<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[],"tags":[],"class_list":["post-100173","calculator","type-calculator","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100173","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator"}],"about":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/types\/calculator"}],"version-history":[{"count":1,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100173\/revisions"}],"predecessor-version":[{"id":100488,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100173\/revisions\/100488"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/media?parent=100173"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/categories?post=100173"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/tags?post=100173"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}