{"id":100028,"date":"2026-02-15T20:07:12","date_gmt":"2026-02-15T20:07:12","guid":{"rendered":"https:\/\/vibromera.eu\/?post_type=calculator&#038;p=100028"},"modified":"2026-02-15T20:07:12","modified_gmt":"2026-02-15T20:07:12","slug":"bearing-speed-factor","status":"publish","type":"calculator","link":"https:\/\/vibromera.eu\/nb\/calculators\/bearing-speed-factor\/","title":{"rendered":"Kalkulator for lagerhastighetsfaktor n\u00d7dm | Fett- og oljegrenser | Gratis online verkt\u00f8y"},"content":{"rendered":"\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"WebApplication\",\"name\":\"Bearing Speed Factor n\u00d7dm Calculator\",\"description\":\"Free calculator for bearing speed factor n\u00d7dm with lubrication limit comparison.\",\"url\":\"https:\/\/vibromera.eu\/calculators\/bearing-speed-factor\/\",\"applicationCategory\":\"Engineering Calculator\",\"operatingSystem\":\"Any\",\"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}<\/script>\n\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[\n{\"@type\":\"Question\",\"name\":\"What is the n\u00d7dm speed factor?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"n\u00d7dm is the product of rotational speed (RPM) and mean bearing diameter dm = (d+D)\/2 in mm. It is a key parameter for assessing whether a bearing can operate at a given speed with grease or oil lubrication.\"}},\n{\"@type\":\"Question\",\"name\":\"What are typical n\u00d7dm limits for grease lubrication?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"For standard grease: DGBB up to 500,000, ACBB up to 450,000, CRB up to 350,000, SRB up to 250,000. With high-speed greases, these limits can increase by 30-50%.\"}},\n{\"@type\":\"Question\",\"name\":\"When should I switch from grease to oil lubrication?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Switch to oil when n\u00d7dm exceeds the grease limit for your bearing type, typically above 300,000-500,000 for ball bearings. Oil lubrication also allows better heat removal at high speeds.\"}},\n{\"@type\":\"Question\",\"name\":\"How does bearing type affect speed limits?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Ball bearings have the highest speed capability due to point contact. Cylindrical roller bearings are next, followed by tapered roller and spherical roller bearings which have the lowest limits due to sliding contact.\"}},\n{\"@type\":\"Question\",\"name\":\"Can I exceed the n\u00d7dm limit?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Exceeding the limit may work briefly but will lead to excessive heat, grease degradation, cage wear, and premature failure. For high-speed applications, use precision bearings (P5\/P4) with proper lubrication.\"}}\n]}<\/script>\n\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"BreadcrumbList\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/vibromera.eu\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Calculators\",\"item\":\"https:\/\/vibromera.eu\/calculators\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Bearing Speed Factor\",\"item\":\"https:\/\/vibromera.eu\/calculators\/bearing-speed-factor\/\"}]}<\/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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p:last-child{margin-bottom:0}.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 .15s}.vc-related-link:hover{border-color:var(--vc-accent);color:var(--vc-accent);background:var(--vc-accent-light)}.vc-promo{margin-top:24px;padding:20px;background:linear-gradient(135deg,var(--vc-accent-light),var(--vc-surface));border:1px solid var(--vc-border);border-radius:var(--vc-radius-lg);display:flex;align-items:center;gap:16px}.vc-promo-text{flex:1;font-size:14px;color:var(--vc-ink-secondary)}.vc-promo-text strong{color:var(--vc-ink)}.vc-promo-link{padding:8px 20px;font-size:13px;font-weight:700;color:#fff;background:var(--vc-accent);border-radius:var(--vc-radius);text-decoration:none;white-space:nowrap;transition:background .15s}.vc-promo-link:hover{background:var(--vc-accent-hover)}.vc-footer{text-align:center;padding:32px 16px;font-size:13px;color:var(--vc-ink-muted)}.vc-footer a{color:var(--vc-accent);text-decoration:none}.vc-footer a:hover{text-decoration:underline}.vc-footer-links{margin-top:8px;font-size:12px}.vc-footer-links a{margin:0 8px}@media 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}}<\/style>\n\n<div class=\"vc-calculator\">\n<header class=\"vc-header\">\n    <p class=\"vc-header-eyebrow\">Free Engineering Tool #053<\/p>\n    <h1 class=\"vc-header-title\">Bearing Speed Factor n\u00d7d<sub>m<\/sub> Calculator<\/h1>\n    <p class=\"vc-header-subtitle\">Calculate the n\u00d7d<sub>m<\/sub> speed factor and compare against limiting values for grease and oil lubrication by bearing type.<\/p>\n    <div class=\"vc-badges\"><span class=\"vc-badge\">n \u00d7 dm<\/span><span class=\"vc-badge\">Grease Limit<\/span><span class=\"vc-badge\">Oil Limit<\/span><\/div>\n<\/header>\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\"><label class=\"vc-label\" for=\"vc-bore\">Bore d <span class=\"vc-label-hint\">(mm)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-bore\" inputmode=\"decimal\" step=\"any\" min=\"1\" value=\"40\"><\/div>\n            <div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-od\">OD D <span class=\"vc-label-hint\">(mm)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-od\" inputmode=\"decimal\" step=\"any\" min=\"1\" value=\"80\"><\/div>\n            <div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-speed\">Speed <span class=\"vc-label-hint\">(RPM)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-speed\" inputmode=\"decimal\" step=\"any\" min=\"1\" value=\"3000\"><\/div>\n            <div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-btype\">Bearing Type<\/label>\n                <select class=\"vc-select\" id=\"vc-btype\"><option value=\"dgbb\" selected>Deep groove ball (DGBB)<\/option><option value=\"acbb\">Angular contact ball (ACBB)<\/option><option value=\"crb\">Cylindrical roller (CRB)<\/option><option value=\"trb\">Tapered roller (TRB)<\/option><option value=\"srb\">Spherical roller (SRB)<\/option><\/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-d=\"40\" data-D=\"80\" data-n=\"3000\" data-bt=\"dgbb\">6208 \/ 3000 RPM<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-d=\"25\" data-D=\"52\" data-n=\"10000\" data-bt=\"acbb\">7205 ACBB \/ 10000<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-d=\"80\" data-D=\"170\" data-n=\"1500\" data-bt=\"srb\">22216 SRB \/ 1500<\/button>\n        <\/div>\n    <\/form>\n    <div class=\"vc-results\" id=\"vc-results\">\n        <div class=\"vc-results-head\"><h2 class=\"vc-results-title\">Results<\/h2><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><\/div>\n        <div class=\"vc-result-grid\">\n            <div class=\"vc-rcard vc-rcard-primary\"><div class=\"vc-rcard-label\">Speed Factor n \u00d7 dm<\/div><div class=\"vc-rcard-value\" id=\"vc-r-ndm\">\u2014<\/div><\/div>\n            <div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Grease Limit<\/div><div class=\"vc-rcard-value\" id=\"vc-r-glim\">\u2014<\/div><\/div>\n            <div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Oil Limit<\/div><div class=\"vc-rcard-value\" id=\"vc-r-olim\">\u2014<\/div><\/div>\n            <div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Assessment<\/div><div class=\"vc-rcard-value\" id=\"vc-r-assess\">\u2014<\/div><\/div>\n            <div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Mean Diameter dm<\/div><div class=\"vc-rcard-value\" id=\"vc-r-dm\">\u2014<\/div><\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<div class=\"vc-section vc-open\" id=\"vc-sec-theory\"><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\"><div class=\"vc-section-inner vc-theory\">\n        <h3>Speed Factor Formula<\/h3>\n        <div class=\"vc-formula-box\" id=\"vc-katex-1\"><\/div>\n        <h3>Limiting n\u00d7dm Values (typical, \u00d710\u00b3)<\/h3>\n        <table class=\"vc-table\">\n            <thead><tr><th>Bearing Type<\/th><th>Grease Limit<\/th><th>Oil Limit<\/th><\/tr><\/thead>\n            <tbody><tr><td>Deep groove ball (DGBB)<\/td><td>500,000<\/td><td>700,000<\/td><\/tr><tr><td>Angular contact ball (ACBB)<\/td><td>450,000<\/td><td>650,000<\/td><\/tr><tr><td>Cylindrical roller (CRB)<\/td><td>350,000<\/td><td>550,000<\/td><\/tr><tr><td>Tapered roller (TRB)<\/td><td>250,000<\/td><td>400,000<\/td><\/tr><tr><td>Spherical roller (SRB)<\/td><td>200,000<\/td><td>350,000<\/td><\/tr><\/tbody>\n        <\/table>\n    <\/div><\/div>\n<\/div>\n\n<div class=\"vc-section\" id=\"vc-sec-related\"><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\"><a class=\"vc-related-link\" href=\"\/calculators\/bearing-grease-quantity\/\">Grease Quantity<\/a><a class=\"vc-related-link\" href=\"\/calculators\/bearing-relubrication-interval\/\">Relubrication Interval<\/a><a class=\"vc-related-link\" href=\"\/calculators\/bearing-minimum-load\/\">Minimum Load<\/a><a class=\"vc-related-link\" href=\"\/calculators\/bearing-modified-life-l10a\/\">Bearing Life L10a<\/a><\/div><\/div><\/div>\n<\/div>\n<div class=\"vc-section\" id=\"vc-sec-faq\"><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<div class=\"vc-promo\"><div class=\"vc-promo-text\"><strong>Vibromera \u2014 Portable Balancing &amp; Vibration Analysis<\/strong><br>Professional vibration analyzers. 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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<script src=\"https:\/\/cdn.jsdelivr.net\/npm\/katex@0.16.11\/dist\/katex.min.js\"><\/script>\n<script>\n(function(){\n    'use strict';var SLUG='bearing-speed-factor';\n    function $(id){return document.getElementById(id)}\n    function fmtK(n){if(isNaN(n))return'\u2014';return Math.round(n).toLocaleString('en-US');}\n    var LIMITS={dgbb:{grease:500000,oil:700000},acbb:{grease:450000,oil:650000},crb:{grease:350000,oil:550000},trb:{grease:250000,oil:400000},srb:{grease:200000,oil:350000}};\n\n    function calculate(){\n        var d=parseFloat($('vc-bore').value),D=parseFloat($('vc-od').value),n=parseFloat($('vc-speed').value),bt=$('vc-btype').value;\n        if(!d||d<=0||!D||D<=d||!n||n<=0){$('vc-results').classList.remove('vc-visible');return;}\n        var dm=(d+D)\/2,ndm=n*dm;var lim=LIMITS[bt];\n        var assess,cls;\n        if(ndm<=lim.grease){assess='OK for grease & oil';cls='vc-status-pass';}\n        else if(ndm<=lim.oil){assess='Oil lubrication required';cls='vc-status-warn';}\n        else{assess='EXCEEDS oil limit \u2014 special design needed';cls='vc-status-fail';}\n        $('vc-r-ndm').innerHTML=fmtK(ndm)+' <span class=\"vc-rcard-unit\">mm\u00b7RPM<\/span>';\n        $('vc-r-glim').innerHTML=fmtK(lim.grease);\n        $('vc-r-olim').innerHTML=fmtK(lim.oil);\n        $('vc-r-assess').innerHTML='<span class=\"'+cls+'\" style=\"font-size:16px\">'+assess+'<\/span>';\n        $('vc-r-dm').innerHTML=(dm).toFixed(1)+' <span class=\"vc-rcard-unit\">mm<\/span>';\n        $('vc-results').classList.add('vc-visible');\n        var u=new URL(window.location);u.searchParams.set('d',d);u.searchParams.set('D',D);u.searchParams.set('n',n);u.searchParams.set('bt',bt);history.replaceState(null,'',u.toString());\n        saveHistory({d:d,D:D,n:n,bt:bt,_summary:'n\u00d7dm='+fmtK(ndm)});\n    }\n\n    document.querySelectorAll('.vc-preset-btn').forEach(function(btn){btn.addEventListener('click',function(e){e.preventDefault();$('vc-bore').value=this.getAttribute('data-d');$('vc-od').value=this.getAttribute('data-D');$('vc-speed').value=this.getAttribute('data-n');$('vc-btype').value=this.getAttribute('data-bt');calculate();});});\n    $('vc-form').addEventListener('input',calculate);$('vc-form').addEventListener('change',calculate);\n    $('vc-copy-btn').addEventListener('click',function(){var text='Bearing Speed Factor\\n\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\\nn\u00d7dm = '+$('vc-r-ndm').textContent+'\\nGrease limit: '+$('vc-r-glim').textContent+'\\nOil limit: '+$('vc-r-olim').textContent+'\\n'+$('vc-r-assess').textContent+'\\n\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\\nvibromera.eu';if(navigator.clipboard){navigator.clipboard.writeText(text).then(function(){var b=$('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    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    var faqData=[{q:'What is the n\u00d7dm speed factor?',a:'<p>n\u00d7dm is the product of rotational speed (RPM) and mean bearing diameter dm = (d+D)\/2 in mm. 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Skriv inn boring, ytterdiameter og hastighet. 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