{"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":"2026-07-11T19:38:35","modified_gmt":"2026-07-11T19:38:35","slug":"bearing-speed-factor","status":"publish","type":"calculator","link":"https:\/\/vibromera.eu\/es\/calculators\/bearing-speed-factor\/","title":{"rendered":"Calculadora del factor de velocidad del rodamiento n\u00d7dm | L\u00edmites de grasa y aceite | Herramienta en l\u00ednea gratuita"},"content":{"rendered":"\r\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"WebApplication\",\"name\":\"Bearing Speed Factor n\u00d7dm Calculator\",\"description\":\"Calculate bearing mean diameter dm and speed factor n\u00d7dm for use with the exact bearing and lubricant manufacturer data. No universal grease or oil limit is applied.\",\"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\":\"2026-07-11\",\"inLanguage\":\"en\",\"isAccessibleForFree\":true}<\/script>\r\n\r\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[\r\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.\"}},\r\n{\"@type\":\"Question\",\"name\":\"Is there a universal n\u00d7dm grease limit?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"No. Permissible speed and grease suitability depend on the exact bearing design, size, cage, seals, clearance, load, temperature, lubricant and heat dissipation. Use the current product table and lubricant data.\"}},\r\n{\"@type\":\"Question\",\"name\":\"Can n\u00d7dm alone select grease or oil?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"No. n\u00d7dm is a useful speed parameter, but lubrication selection also requires the exact bearing, load, operating temperature, viscosity, grease performance, relubrication method and thermal design.\"}},\r\n{\"@type\":\"Question\",\"name\":\"Where should I obtain the limiting speed?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Use the limiting and reference speeds published for the exact bearing designation and execution by its manufacturer. A bearing-family name alone is insufficient.\"}},\r\n{\"@type\":\"Question\",\"name\":\"Does a low n\u00d7dm prove the application is safe?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"No. n\u00d7dm does not check load, minimum load, cage stress, lubrication film, temperature, clearance, sealing, alignment or critical speed. It is only one input to bearing selection.\"}}\r\n]}<\/script>\r\n\r\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>\r\n\r\n<link rel=\"preconnect\" href=\"https:\/\/fonts.googleapis.com\">\r\n\r\n<link rel=\"preconnect\" href=\"https:\/\/fonts.gstatic.com\" crossorigin>\r\n\r\n<link href=\"https:\/\/fonts.googleapis.com\/css2?family=DM+Sans:ital,opsz,wght@0,9..40,300;0,9..40,400;0,9..40,500;0,9..40,600;0,9..40,700;1,9..40,400&#038;family=JetBrains+Mono:wght@400;500;600&#038;family=Fraunces:opsz,wght@9..144,700;9..144,800&#038;display=swap\" rel=\"stylesheet\">\r\n\r\n<link rel=\"stylesheet\" href=\"https:\/\/cdn.jsdelivr.net\/npm\/katex@0.16.11\/dist\/katex.min.css\">\r\n\r\n<style>:root{--vc-bg:#f4f1ec;--vc-surface:#fff;--vc-surface-alt:#f8f6f2;--vc-ink:#1a1a1a;--vc-ink-secondary:#5a5650;--vc-ink-muted:#8a857e;--vc-accent:#c85a2a;--vc-accent-hover:#b04d22;--vc-accent-light:#fdf0ea;--vc-blue:#2a5c8c;--vc-blue-light:#eaf1f8;--vc-green:#2a7a4b;--vc-green-light:#eaf8ef;--vc-yellow:#a67c00;--vc-yellow-light:#fef9e8;--vc-red:#b91c1c;--vc-red-light:#fef2f2;--vc-border:#d9d4cc;--vc-border-light:#e8e4dd;--vc-shadow:0 1px 3px rgba(26,26,26,.06),0 4px 12px rgba(26,26,26,.04);--vc-radius:8px;--vc-radius-lg:12px;--vc-font:'DM Sans',-apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif;--vc-mono:'JetBrains Mono','Consolas','Monaco',monospace;--vc-display:'Fraunces',Georgia,serif}.vc-calculator{font-family:var(--vc-font);font-size:15px;line-height:1.65;color:var(--vc-ink);max-width:960px;margin:0 auto;padding:20px 16px 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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>\r\n\r\n<div class=\"vc-calculator\">\r\n<header class=\"vc-header\">\r\n    <p class=\"vc-header-eyebrow\">Free Engineering Tool #053<\/p>\r\n    <h1 class=\"vc-header-title\">Bearing Speed Factor n\u00d7d<sub>m<\/sub> Calculator<\/h1>\r\n    <p class=\"vc-header-subtitle\">Calculate mean diameter d<sub>m<\/sub> and speed factor n\u00d7d<sub>m<\/sub>. Compare the result only with data for the exact bearing and lubricant.<\/p>\r\n    <div class=\"vc-badges\"><span class=\"vc-badge\">n \u00d7 dm<\/span><span class=\"vc-badge\">Verified Formula<\/span><span class=\"vc-badge\">Manufacturer Limit Required<\/span><\/div>\r\n<\/header>\r\n<div class=\"vc-card\">\r\n    <form class=\"vc-form\" id=\"vc-form\" autocomplete=\"off\">\r\n        <div class=\"vc-form-grid\">\r\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=\"text\" id=\"vc-bore\" inputmode=\"decimal\" autocomplete=\"off\" value=\"40\"><\/div>\r\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=\"text\" id=\"vc-od\" inputmode=\"decimal\" autocomplete=\"off\" value=\"80\"><\/div>\r\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=\"text\" id=\"vc-speed\" inputmode=\"decimal\" autocomplete=\"off\" value=\"3000\"><\/div>\r\n        <\/div>\r\n        <div class=\"vc-warning-box\"><p><strong>No universal limit is applied.<\/strong> The previous grease\/oil thresholds were not traceable to a specific bearing or lubricant manufacturer and omitted essential operating conditions.<\/p><\/div>\r\n    <\/form>\r\n    <div class=\"vc-results\" id=\"vc-results\">\r\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>\r\n        <div class=\"vc-result-grid\">\r\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>\r\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>\r\n        <\/div>\r\n    <\/div>\r\n<\/div>\r\n\r\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>\r\n    <div class=\"vc-section-body\"><div class=\"vc-section-inner vc-theory\">\r\n        <h3>Speed Factor Formula<\/h3>\r\n        <div class=\"vc-formula-box\" id=\"vc-katex-1\"><\/div>\r\n        <h3>Interpretation<\/h3>\r\n        <p>n\u00d7d<sub>m<\/sub> is a speed parameter used in lubricant and relubrication guidance. It is not the bearing limiting speed and does not by itself decide grease versus oil. Use the exact bearing designation, execution, cage, seals, load, temperature and lubricant in current manufacturer documentation.<\/p>\r\n        <div class=\"vc-info-box\"><p>For outer-ring rotation or special arrangements, the manufacturer may specify a different speed parameter or correction. Follow that definition instead of assuming n\u00d7d<sub>m<\/sub>.<\/p><\/div>\r\n    <\/div><\/div>\r\n<\/div>\r\n\r\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>\r\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>\r\n<\/div>\r\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>\r\n    <div class=\"vc-section-body\"><div class=\"vc-section-inner\"><div class=\"vc-faq-list\" id=\"vc-faq-list\"><\/div><\/div><\/div>\r\n<\/div>\r\n<div class=\"vc-promo\"><div class=\"vc-promo-text\"><strong>Vibromera \u2014 Portable Balancing &amp; Vibration Analysis<\/strong><br>Professional vibration analyzers. Used in 50+ countries.<\/div><a class=\"vc-promo-link\" href=\"https:\/\/vibromera.eu\/\" target=\"_blank\" rel=\"noopener\">Learn More<\/a><\/div>\r\n<footer class=\"vc-footer\"><p>\u00a9 2024\u20132026 <a href=\"https:\/\/vibromera.eu\/\">Vibromera<\/a><\/p><p style=\"font-size:12px;margin-top:4px;\">Universal lubrication limits removed. 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It is a useful speed parameter, not a universal permission limit.<\/p>'},{q:'Is there a universal grease limit?',a:'<p>No. Use current manufacturer data for the exact bearing, cage, seals, load, temperature and grease.<\/p>'},{q:'Can n\u00d7dm select grease or oil?',a:'<p>No. Lubrication selection also needs load, temperature, viscosity, grease performance, replenishment and thermal design.<\/p>'},{q:'Where is limiting speed found?',a:'<p>Use reference and limiting speeds for the exact bearing designation and execution in its current product table.<\/p>'},{q:'Does low n\u00d7dm prove safety?',a:'<p>No. It omits load, minimum load, cage stress, film thickness, clearance, sealing, alignment and rotor critical speed.<\/p>'}];\r\n    var fl=$('vc-faq-list');faqData.forEach(function(f){fl.innerHTML+='<div class=\"vc-faq-item\"><button type=\"button\" class=\"vc-faq-q\"><span>'+f.q+'<\/span><svg class=\"vc-faq-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button><div class=\"vc-faq-a\"><div class=\"vc-faq-a-inner\">'+f.a+'<\/div><\/div><\/div>';});\r\n    fl.addEventListener('click',function(e){var b=e.target.closest('.vc-faq-q');if(b)b.closest('.vc-faq-item').classList.toggle('vc-open');});\r\n    function saveHistory(entry){var key='vc_history_'+SLUG;var arr=[];try{arr=JSON.parse(localStorage.getItem(key))||[];}catch(e){}entry._ts=new Date().toISOString();arr.unshift(entry);if(arr.length>10)arr=arr.slice(0,10);try{localStorage.setItem(key,JSON.stringify(arr));}catch(e){}}\r\n    function loadParams(){var p=new URLSearchParams(window.location.search);if(p.has('d'))$('vc-bore').value=p.get('d');if(p.has('D'))$('vc-od').value=p.get('D');if(p.has('n'))$('vc-speed').value=p.get('n');}\r\n    function renderFormulas(){try{katex.render('n \\\\times d_m = n \\\\times \\\\frac{d+D}{2} \\\\quad [\\\\text{mm\u00b7r\/min}]',$('vc-katex-1'),{displayMode:true,throwOnError:false});}catch(e){}}\r\n    function init(){loadParams();renderFormulas();calculate();}\r\n    if(document.readyState==='loading'){document.addEventListener('DOMContentLoaded',init);}else{init();}\r\n})();\r\n<\/script>\r\n","protected":false},"excerpt":{"rendered":"<p>Calculadora en l\u00ednea gratuita para el factor de velocidad del rodamiento n\u00d7dm. Introduzca el di\u00e1metro interior, el di\u00e1metro exterior y la velocidad. Comp\u00e1rela con los valores l\u00edmite de n\u00d7dm para lubricaci\u00f3n con grasa y aceite.<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[],"tags":[],"class_list":["post-100028","calculator","type-calculator","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/es\/wp-json\/wp\/v2\/calculator\/100028","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vibromera.eu\/es\/wp-json\/wp\/v2\/calculator"}],"about":[{"href":"https:\/\/vibromera.eu\/es\/wp-json\/wp\/v2\/types\/calculator"}],"version-history":[{"count":2,"href":"https:\/\/vibromera.eu\/es\/wp-json\/wp\/v2\/calculator\/100028\/revisions"}],"predecessor-version":[{"id":102314,"href":"https:\/\/vibromera.eu\/es\/wp-json\/wp\/v2\/calculator\/100028\/revisions\/102314"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/es\/wp-json\/wp\/v2\/media?parent=100028"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/es\/wp-json\/wp\/v2\/categories?post=100028"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/es\/wp-json\/wp\/v2\/tags?post=100028"}],"curies":[{"name":"gracias","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}