{"id":100024,"date":"2026-02-15T20:09:04","date_gmt":"2026-02-15T20:09:04","guid":{"rendered":"https:\/\/vibromera.eu\/?post_type=calculator&#038;p=100024"},"modified":"2026-02-15T20:09:04","modified_gmt":"2026-02-15T20:09:04","slug":"bearing-modified-life-l10a","status":"publish","type":"calculator","link":"https:\/\/vibromera.eu\/pt_br\/calculators\/bearing-modified-life-l10a\/","title":{"rendered":"Calculadora de Vida \u00datil Modificada de Rolamentos L10a | ISO 281 | Ferramenta Online Gratuita"},"content":{"rendered":"\n<script type=\"application\/ld+json\">\n{\"@context\":\"https:\/\/schema.org\",\"@type\":\"WebApplication\",\"name\":\"Bearing Modified Life L10a Calculator\",\"alternateName\":[\"ISO 281 Bearing Life Calculator\",\"Adjusted Rating Life Calculator\",\"L10a Calculator\"],\"description\":\"Free online engineering calculator for bearing adjusted rating life L10a per ISO 281. Computes modified life using reliability factor a1 and life modification factor aISO.\",\"url\":\"https:\/\/vibromera.eu\/calculators\/bearing-modified-life-l10a\/\",\"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\":[\"Ball and roller bearing support\",\"Reliability factor a1 (0.62\u20131.0)\",\"Life modification factor aISO\",\"Hours and revolutions output\",\"Auto-calculation on input change\",\"Preset examples\"],\"keywords\":\"bearing life, L10a, ISO 281, modified rating life, reliability factor, lubrication factor\"}\n<\/script>\n\n<script type=\"application\/ld+json\">\n{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[\n{\"@type\":\"Question\",\"name\":\"What is the bearing modified life L10a?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"L10a is the adjusted rating life of a rolling bearing per ISO 281. It modifies the basic rating life L10 using a reliability factor a1 and a life modification factor aISO that accounts for lubrication, contamination, and fatigue load limit.\"}},\n{\"@type\":\"Question\",\"name\":\"What is the difference between L10 and L10a?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"L10 is the basic rating life \u2014 the number of revolutions at which 90% of a group of identical bearings will survive. L10a adjusts this value using factors for reliability (a1) and operating conditions (aISO), giving a more realistic life prediction.\"}},\n{\"@type\":\"Question\",\"name\":\"How do I choose the reliability factor a1?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"a1 depends on the desired survival probability. For 90% reliability (standard), a1 = 1.0. For 95% reliability, a1 = 0.64. For 99% reliability, a1 = 0.21. Higher reliability requirements reduce the calculated life.\"}},\n{\"@type\":\"Question\",\"name\":\"What does the life exponent p mean?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"The life exponent p is 3 for ball bearings and 10\/3 for roller bearings. It appears in the basic rating life formula L10 = (C\/P)^p and reflects the different contact geometry (point vs line contact).\"}},\n{\"@type\":\"Question\",\"name\":\"What is a typical aISO value?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"aISO depends on lubrication adequacy, contamination, and the ratio of fatigue load limit to actual load. For clean oil lubrication with adequate viscosity, aISO can range from 1 to 50. For poor lubrication or heavy contamination, it may be below 1.\"}}\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\":\"Bearing Modified Life L10a\",\"item\":\"https:\/\/vibromera.eu\/calculators\/bearing-modified-life-l10a\/\"}\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 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\">\n\n<link rel=\"stylesheet\" href=\"https:\/\/cdn.jsdelivr.net\/npm\/katex@0.16.11\/dist\/katex.min.css\">\n\n<style>\n:root {\n    --vc-bg: #f4f1ec;\n    --vc-surface: #ffffff;\n    --vc-surface-alt: #f8f6f2;\n    --vc-ink: #1a1a1a;\n    --vc-ink-secondary: #5a5650;\n    --vc-ink-muted: #8a857e;\n    --vc-accent: #c85a2a;\n    --vc-accent-hover: #b04d22;\n    --vc-accent-light: #fdf0ea;\n    --vc-blue: #2a5c8c;\n    --vc-blue-light: #eaf1f8;\n    --vc-green: #2a7a4b;\n    --vc-green-light: #eaf8ef;\n    --vc-yellow: #a67c00;\n    --vc-yellow-light: #fef9e8;\n    --vc-red: #b91c1c;\n    --vc-red-light: #fef2f2;\n    --vc-border: #d9d4cc;\n    --vc-border-light: #e8e4dd;\n    --vc-shadow: 0 1px 3px rgba(26,26,26,0.06), 0 4px 12px rgba(26,26,26,0.04);\n    --vc-shadow-lg: 0 4px 12px rgba(26,26,26,0.08), 0 16px 40px rgba(26,26,26,0.06);\n    --vc-radius: 8px;\n    --vc-radius-lg: 12px;\n    --vc-font: 'DM Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;\n    --vc-mono: 'JetBrains Mono', 'Consolas', 'Monaco', monospace;\n    --vc-display: 'Fraunces', Georgia, serif;\n}\n\n.vc-calculator {\n    font-family: var(--vc-font);\n    font-size: 15px;\n    line-height: 1.65;\n    color: var(--vc-ink);\n    max-width: 960px;\n    margin: 0 auto;\n    padding: 20px 16px 40px;\n    -webkit-font-smoothing: antialiased;\n}\n.vc-calculator *, .vc-calculator *::before, .vc-calculator *::after { box-sizing: border-box; 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}\n}\n<\/style>\n\n<div class=\"vc-calculator\" id=\"vc-bearing-life\">\n\n<header class=\"vc-header\">\n    <p class=\"vc-header-eyebrow\">Free Engineering Tool #044<\/p>\n    <h1 class=\"vc-header-title\">Bearing Modified Life L<sub>10a<\/sub> Calculator<\/h1>\n    <p class=\"vc-header-subtitle\">Calculate the adjusted rating life of rolling bearings per ISO 281. Enter dynamic load rating, equivalent load, speed, and modification factors.<\/p>\n    <div class=\"vc-badges\">\n        <span class=\"vc-badge\">ISO 281<\/span>\n        <span class=\"vc-badge\">L10a Life<\/span>\n        <span class=\"vc-badge\">Ball &amp; Roller<\/span>\n    <\/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-C\">Dynamic Load Rating C <span class=\"vc-label-hint\">(kN)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-C\" inputmode=\"decimal\" step=\"any\" min=\"0.1\" placeholder=\"e.g. 52.7\" value=\"52.7\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-P\">Equivalent Dynamic Load P <span class=\"vc-label-hint\">(kN)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-P\" inputmode=\"decimal\" step=\"any\" min=\"0.01\" placeholder=\"e.g. 10\" value=\"10\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-speed\">Speed <span class=\"vc-label-hint\">(RPM)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-speed\" inputmode=\"decimal\" step=\"any\" min=\"1\" placeholder=\"e.g. 1500\" value=\"1500\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-type\">Bearing Type<\/label>\n                <select class=\"vc-select\" id=\"vc-type\">\n                    <option value=\"3\" selected>Ball bearing (p = 3)<\/option>\n                    <option value=\"3.333\">Roller bearing (p = 10\/3)<\/option>\n                <\/select>\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-a1\">Reliability Factor a<sub>1<\/sub><\/label>\n                <select class=\"vc-select\" id=\"vc-a1\">\n                    <option value=\"1.00\" selected>90% reliability \u2014 a1 = 1.00<\/option>\n                    <option value=\"0.62\">95% reliability \u2014 a1 = 0.62<\/option>\n                    <option value=\"0.53\">96% reliability \u2014 a1 = 0.53<\/option>\n                    <option value=\"0.44\">97% reliability \u2014 a1 = 0.44<\/option>\n                    <option value=\"0.33\">98% reliability \u2014 a1 = 0.33<\/option>\n                    <option value=\"0.21\">99% reliability \u2014 a1 = 0.21<\/option>\n                <\/select>\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-aiso\">Life Modification Factor a<sub>ISO<\/sub> <span class=\"vc-label-hint\">(lubrication &amp; contamination)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-aiso\" inputmode=\"decimal\" step=\"any\" min=\"0.1\" max=\"50\" placeholder=\"e.g. 1\" value=\"1\">\n            <\/div>\n        <\/div>\n\n        <div class=\"vc-presets\">\n            <div class=\"vc-presets-label\">Quick presets<\/div>\n            <button type=\"button\" class=\"vc-preset-btn\" data-c=\"52.7\" data-p=\"10\" data-s=\"1500\" data-t=\"3\" data-a1=\"1.00\" data-aiso=\"1\">6208 Ball \/ 10 kN \/ 1500 RPM<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-c=\"143\" data-p=\"25\" data-s=\"3000\" data-t=\"3.333\" data-a1=\"1.00\" data-aiso=\"2\">NU310 Roller \/ 25 kN \/ 3000<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-c=\"95.6\" data-p=\"15\" data-s=\"1000\" data-t=\"3\" data-a1=\"0.62\" data-aiso=\"1.5\">6310 Ball \/ 95% rel \/ clean oil<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-c=\"270\" data-p=\"50\" data-s=\"500\" data-t=\"3.333\" data-a1=\"1.00\" data-aiso=\"3\">Large roller \/ clean \/ 500 RPM<\/button>\n        <\/div>\n    <\/form>\n\n    <div class=\"vc-results\" id=\"vc-results\">\n        <div class=\"vc-results-head\">\n            <h2 class=\"vc-results-title\">Results<\/h2>\n            <button type=\"button\" class=\"vc-copy-btn\" id=\"vc-copy-btn\">\n                <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>\n                Copy\n            <\/button>\n        <\/div>\n        <div class=\"vc-result-grid\">\n            <div class=\"vc-rcard vc-rcard-primary\">\n                <div class=\"vc-rcard-label\">Modified Life L10a<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-l10a-hrs\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Basic Life L10<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-l10-hrs\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">L10 (million revolutions)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-l10-rev\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">L10a (million revolutions)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-l10a-rev\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">C\/P Ratio<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-cp\">\u2014<\/div>\n            <\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<!-- Theory -->\n<div class=\"vc-section vc-open\" id=\"vc-sec-theory\">\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"true\">\n        <span class=\"vc-section-toggle-text\">\n            <span class=\"vc-section-icon\">\ud83d\udcd8<\/span>\n            <span class=\"vc-section-title\">Theory &amp; Formulas<\/span>\n        <\/span>\n        <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>\n    <\/button>\n    <div class=\"vc-section-body\">\n        <div class=\"vc-section-inner vc-theory\">\n            <h3>Basic Rating Life L<sub>10<\/sub><\/h3>\n            <p>Per ISO 281, the basic rating life in millions of revolutions is:<\/p>\n            <div class=\"vc-formula-box\" id=\"vc-katex-1\"><\/div>\n            <ul>\n                <li><strong>C<\/strong> \u2014 basic dynamic load rating (kN)<\/li>\n                <li><strong>P<\/strong> \u2014 equivalent dynamic bearing load (kN)<\/li>\n                <li><strong>p<\/strong> \u2014 life exponent: 3 for ball bearings, 10\/3 for roller bearings<\/li>\n            <\/ul>\n\n            <h3>Modified Rating Life L<sub>10a<\/sub><\/h3>\n            <p>The adjusted (modified) rating life accounts for reliability and operating conditions:<\/p>\n            <div class=\"vc-formula-box\" id=\"vc-katex-2\"><\/div>\n            <ul>\n                <li><strong>a<sub>1<\/sub><\/strong> \u2014 life adjustment factor for reliability (1.0 for 90%, 0.21 for 99%)<\/li>\n                <li><strong>a<sub>ISO<\/sub><\/strong> \u2014 life modification factor for lubrication, contamination, and fatigue load limit<\/li>\n            <\/ul>\n\n            <h3>Conversion to Hours<\/h3>\n            <div class=\"vc-formula-box\" id=\"vc-katex-3\"><\/div>\n\n            <h3>Reliability Factor a<sub>1<\/sub><\/h3>\n            <table class=\"vc-table\">\n                <thead><tr><th>Reliability (%)<\/th><th>a<sub>1<\/sub><\/th><th>L<sub>n<\/sub> notation<\/th><\/tr><\/thead>\n                <tbody>\n                    <tr><td>90<\/td><td>1.00<\/td><td>L<sub>10<\/sub><\/td><\/tr>\n                    <tr><td>95<\/td><td>0.62<\/td><td>L<sub>5<\/sub><\/td><\/tr>\n                    <tr><td>96<\/td><td>0.53<\/td><td>L<sub>4<\/sub><\/td><\/tr>\n                    <tr><td>97<\/td><td>0.44<\/td><td>L<sub>3<\/sub><\/td><\/tr>\n                    <tr><td>98<\/td><td>0.33<\/td><td>L<sub>2<\/sub><\/td><\/tr>\n                    <tr><td>99<\/td><td>0.21<\/td><td>L<sub>1<\/sub><\/td><\/tr>\n                <\/tbody>\n            <\/table>\n\n            <h3>Practical Example<\/h3>\n            <div class=\"vc-example-box\">\n                <div class=\"vc-example-title\">Example \u2014 6208 Deep Groove Ball Bearing<\/div>\n                <p><strong>Given:<\/strong> C = 52.7 kN, P = 10 kN, n = 1500 RPM, a<sub>1<\/sub> = 1.0, a<sub>ISO<\/sub> = 1.0<\/p>\n                <p>L<sub>10<\/sub> = (52.7 \/ 10)<sup>3<\/sup> = <strong>146.36 million rev<\/strong><\/p>\n                <p>L<sub>10h<\/sub> = 146.36 \u00d7 10<sup>6<\/sup> \/ (60 \u00d7 1500) = <strong>1,626 hours<\/strong><\/p>\n                <p>L<sub>10a<\/sub> = 1.0 \u00d7 1.0 \u00d7 1,626 = <strong>1,626 hours<\/strong><\/p>\n            <\/div>\n\n            <div class=\"vc-warning-box\">\n                <p style=\"margin:0;font-size:14px;color:var(--vc-ink-secondary);\"><strong>\u26a0\ufe0f Note:<\/strong> The a<sub>ISO<\/sub> factor depends on the viscosity ratio \u03ba and contamination level. Consult bearing manufacturer catalogs (SKF, FAG, NSK) for detailed a<sub>ISO<\/sub> charts. Values from 0.1 to 50 are possible.<\/p>\n            <\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<!-- Related -->\n<div class=\"vc-section\" id=\"vc-sec-related\">\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\">\n        <span class=\"vc-section-toggle-text\">\n            <span class=\"vc-section-icon\">\ud83d\udd17<\/span>\n            <span class=\"vc-section-title\">Related Calculators<\/span>\n        <\/span>\n        <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>\n    <\/button>\n    <div class=\"vc-section-body\">\n        <div class=\"vc-section-inner\">\n            <div class=\"vc-related\">\n                <a class=\"vc-related-link\" href=\"\/calculators\/bearing-static-load-rating\/\">Bearing Static Safety Factor<\/a>\n                <a class=\"vc-related-link\" href=\"\/calculators\/bearing-equivalent-load\/\">Bearing Equivalent Load<\/a>\n                <a class=\"vc-related-link\" href=\"\/calculators\/bearing-speed-factor\/\">Bearing Speed Factor n\u00d7dm<\/a>\n                <a class=\"vc-related-link\" href=\"\/calculators\/bearing-relubrication-interval\/\">Relubrication Interval<\/a>\n                <a class=\"vc-related-link\" href=\"\/calculators\/bearing-grease-quantity\/\">Grease Quantity<\/a>\n            <\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<!-- FAQ -->\n<div class=\"vc-section\" id=\"vc-sec-faq\">\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\">\n        <span class=\"vc-section-toggle-text\">\n            <span class=\"vc-section-icon\">\u2753<\/span>\n            <span class=\"vc-section-title\">Frequently Asked Questions<\/span>\n        <\/span>\n        <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>\n    <\/button>\n    <div class=\"vc-section-body\">\n        <div class=\"vc-section-inner\">\n            <div class=\"vc-faq-list\" id=\"vc-faq-list\"><\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<!-- Promo -->\n<div class=\"vc-promo\">\n    <div class=\"vc-promo-text\">\n        <strong>Vibromera \u2014 Portable Balancing &amp; Vibration Analysis<\/strong><br>\n        Professional field balancing instruments and vibration analyzers. Monitor bearing condition on-site. Used in 50+ countries.\n    <\/div>\n    <a class=\"vc-promo-link\" href=\"https:\/\/vibromera.eu\/\" target=\"_blank\" rel=\"noopener\">Learn More<\/a>\n<\/div>\n\n<footer class=\"vc-footer\">\n    <p>\u00a9 2024\u20132026 <a href=\"https:\/\/vibromera.eu\/\">Vibromera<\/a> \u2014 Engineering Calculators<\/p>\n    <p style=\"font-size:12px;margin-top:4px;\">Based on ISO 281. Calculator #044. Last updated: February 2026<\/p>\n    <div class=\"vc-footer-links\">\n        <a href=\"\/calculators\/engineering-calculators\/\">All Calculators<\/a>\n        <a href=\"https:\/\/vibromera.eu\/contacts\/\">Contact<\/a>\n    <\/div>\n<\/footer>\n\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\n    var SLUG = 'bearing-modified-life-l10a';\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    function fmtInt(n) { if(isNaN(n)||!isFinite(n)) return '\u2014'; return Math.round(n).toLocaleString('en-US'); }\n\n    function calculate() {\n        var C = parseFloat($('vc-C').value);\n        var P = parseFloat($('vc-P').value);\n        var speed = parseFloat($('vc-speed').value);\n        var p = parseFloat($('vc-type').value);\n        var a1 = parseFloat($('vc-a1').value);\n        var aiso = parseFloat($('vc-aiso').value);\n\n        if (!C || C <= 0 || !P || P <= 0 || !speed || speed <= 0 || !aiso || aiso <= 0) {\n            $('vc-results').classList.remove('vc-visible');\n            return;\n        }\n\n        var cp = C \/ P;\n        var L10_rev = Math.pow(cp, p); \/\/ million revolutions\n        var L10_hrs = L10_rev * 1e6 \/ (60 * speed);\n        var L10a_rev = a1 * aiso * L10_rev;\n        var L10a_hrs = a1 * aiso * L10_hrs;\n\n        $('vc-r-l10a-hrs').innerHTML = fmtInt(L10a_hrs) + ' <span class=\"vc-rcard-unit\">hours<\/span>';\n        $('vc-r-l10-hrs').innerHTML = fmtInt(L10_hrs) + ' <span class=\"vc-rcard-unit\">hours<\/span>';\n        $('vc-r-l10-rev').innerHTML = fmt(L10_rev, 1) + ' <span class=\"vc-rcard-unit\">\u00d710\u2076 rev<\/span>';\n        $('vc-r-l10a-rev').innerHTML = fmt(L10a_rev, 1) + ' <span class=\"vc-rcard-unit\">\u00d710\u2076 rev<\/span>';\n        $('vc-r-cp').innerHTML = fmt(cp, 2);\n\n        $('vc-results').classList.add('vc-visible');\n\n        var u = new URL(window.location);\n        u.searchParams.set('C', C); u.searchParams.set('P', P); u.searchParams.set('speed', speed);\n        u.searchParams.set('type', p); u.searchParams.set('a1', a1); u.searchParams.set('aiso', aiso);\n        history.replaceState(null, '', u.toString());\n\n        saveHistory({ C:C, P:P, speed:speed, p:p, a1:a1, aiso:aiso, _summary:'C='+C+'kN, P='+P+'kN, n='+speed+' RPM \u2192 L10a='+fmtInt(L10a_hrs)+' h' });\n    }\n\n    \/* Presets *\/\n    document.querySelectorAll('.vc-preset-btn').forEach(function(btn) {\n        btn.addEventListener('click', function(e) {\n            e.preventDefault();\n            $('vc-C').value = this.getAttribute('data-c');\n            $('vc-P').value = this.getAttribute('data-p');\n            $('vc-speed').value = this.getAttribute('data-s');\n            $('vc-type').value = this.getAttribute('data-t');\n            $('vc-a1').value = this.getAttribute('data-a1');\n            $('vc-aiso').value = this.getAttribute('data-aiso');\n            calculate();\n        });\n    });\n\n    $('vc-form').addEventListener('input', calculate);\n    $('vc-form').addEventListener('change', calculate);\n\n    \/* Copy *\/\n    $('vc-copy-btn').addEventListener('click', function() {\n        var text = 'Bearing Modified Life L10a\\n\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\\n' +\n            'C = ' + $('vc-C').value + ' kN\\nP = ' + $('vc-P').value + ' kN\\n' +\n            'Speed: ' + $('vc-speed').value + ' RPM\\n' +\n            'a1 = ' + $('vc-a1').value + ', aISO = ' + $('vc-aiso').value + '\\n' +\n            'L10a: ' + $('vc-r-l10a-hrs').textContent + '\\n' +\n            'L10: ' + $('vc-r-l10-hrs').textContent + '\\n' +\n            '\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\\nvibromera.eu';\n        if(navigator.clipboard){navigator.clipboard.writeText(text).then(function(){\n            var b=$('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!';\n            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    });\n\n    \/* Sections *\/\n    document.querySelectorAll('.vc-section-toggle').forEach(function(btn) {\n        btn.addEventListener('click', function() {\n            var s = this.closest('.vc-section'); 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It modifies the basic rating life L10 using a reliability factor a<sub>1<\/sub> and a life modification factor a<sub>ISO<\/sub> that accounts for lubrication, contamination, and fatigue load limit.<\/p><p>It provides a more realistic life prediction than the basic L10 formula alone.<\/p>'},\n        {q:'What is the difference between L10 and L10a?',a:'<p>L10 is the basic rating life \u2014 the number of revolutions at which 90% of a group of identical bearings will survive under ideal conditions. L10a adjusts this value using factors for reliability (a<sub>1<\/sub>) and operating conditions (a<sub>ISO<\/sub>), giving a more accurate life prediction.<\/p>'},\n        {q:'How do I choose the reliability factor a1?',a:'<p>a<sub>1<\/sub> depends on the desired survival probability:<\/p><ul><li><strong>a<sub>1<\/sub> = 1.00<\/strong> \u2014 90% reliability (standard)<\/li><li><strong>a<sub>1<\/sub> = 0.62<\/strong> \u2014 95% reliability<\/li><li><strong>a<sub>1<\/sub> = 0.33<\/strong> \u2014 98% reliability<\/li><li><strong>a<sub>1<\/sub> = 0.21<\/strong> \u2014 99% reliability<\/li><\/ul><p>Higher reliability requirements mean lower a<sub>1<\/sub> and shorter calculated life.<\/p>'},\n        {q:'What does the life exponent p mean?',a:'<p>The life exponent p is 3 for ball bearings and 10\/3 for roller bearings. It appears in the basic rating life formula L<sub>10<\/sub> = (C\/P)<sup>p<\/sup> and reflects the different contact geometry: point contact for balls, line contact for rollers.<\/p>'},\n        {q:'What is a typical aISO value?',a:'<p>a<sub>ISO<\/sub> depends on the viscosity ratio \u03ba, contamination level, and the ratio C<sub>u<\/sub>\/P (fatigue load limit to actual load):<\/p><ul><li><strong>0.1\u20130.5<\/strong> \u2014 severe contamination, poor lubrication<\/li><li><strong>1<\/strong> \u2014 standard conditions (default)<\/li><li><strong>2\u201310<\/strong> \u2014 clean oil, adequate viscosity<\/li><li><strong>10\u201350<\/strong> \u2014 very clean, excellent lubrication<\/li><\/ul><p>Consult SKF, FAG, or NSK catalogs for detailed a<sub>ISO<\/sub> diagrams.<\/p>'}\n    ];\n    var fl = $('vc-faq-list');\n    faqData.forEach(function(f){fl.innerHTML+='<div class=\"vc-faq-item\"><button type=\"button\" class=\"vc-faq-q\"><span>'+f.q+'<\/span><svg class=\"vc-faq-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button><div class=\"vc-faq-a\"><div class=\"vc-faq-a-inner\">'+f.a+'<\/div><\/div><\/div>';});\n    fl.addEventListener('click',function(e){var b=e.target.closest('.vc-faq-q');if(b)b.closest('.vc-faq-item').classList.toggle('vc-open');});\n\n    \/* History *\/\n    function saveHistory(entry){var key='vc_history_'+SLUG;var arr=[];try{arr=JSON.parse(localStorage.getItem(key))||[];}catch(e){}entry._ts=new Date().toISOString();arr.unshift(entry);if(arr.length>10)arr=arr.slice(0,10);try{localStorage.setItem(key,JSON.stringify(arr));}catch(e){}}\n\n    \/* URL Params *\/\n    function loadParams(){var p=new URLSearchParams(window.location.search);p.forEach(function(v,k){var el=$(k)||$('vc-'+k);if(el)el.value=v;});}\n\n    \/* KaTeX *\/\n    function renderFormulas(){try{\n        katex.render('L_{10} = \\\\left(\\\\frac{C}{P}\\\\right)^p \\\\quad [\\\\text{million revolutions}]', $('vc-katex-1'), {displayMode:true,throwOnError:false});\n        katex.render('L_{10a} = a_1 \\\\times a_{ISO} \\\\times L_{10}', $('vc-katex-2'), {displayMode:true,throwOnError:false});\n        katex.render('L_{10h} = \\\\frac{L_{10} \\\\times 10^6}{60 \\\\times n} \\\\quad [\\\\text{hours}]', $('vc-katex-3'), {displayMode:true,throwOnError:false});\n    }catch(e){}}\n\n    function init(){loadParams();renderFormulas();calculate();}\n    if(document.readyState==='loading'){document.addEventListener('DOMContentLoaded',init);}else{init();}\n})();\n<\/script>\n","protected":false},"excerpt":{"rendered":"<p>Calculadora online gratuita para vida \u00fatil nominal ajustada de rolamentos L10a, conforme ISO 281. Insira a capacidade de carga din\u00e2mica C, a carga equivalente P, a velocidade, o fator de confiabilidade a1 e o fator de lubrifica\u00e7\u00e3o para calcular a vida \u00fatil modificada do rolamento.<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[],"tags":[],"class_list":["post-100024","calculator","type-calculator","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/pt_br\/wp-json\/wp\/v2\/calculator\/100024","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vibromera.eu\/pt_br\/wp-json\/wp\/v2\/calculator"}],"about":[{"href":"https:\/\/vibromera.eu\/pt_br\/wp-json\/wp\/v2\/types\/calculator"}],"version-history":[{"count":1,"href":"https:\/\/vibromera.eu\/pt_br\/wp-json\/wp\/v2\/calculator\/100024\/revisions"}],"predecessor-version":[{"id":100355,"href":"https:\/\/vibromera.eu\/pt_br\/wp-json\/wp\/v2\/calculator\/100024\/revisions\/100355"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/pt_br\/wp-json\/wp\/v2\/media?parent=100024"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/pt_br\/wp-json\/wp\/v2\/categories?post=100024"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/pt_br\/wp-json\/wp\/v2\/tags?post=100024"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}