{"id":100034,"date":"2026-02-15T20:07:32","date_gmt":"2026-02-15T20:07:32","guid":{"rendered":"https:\/\/vibromera.eu\/?post_type=calculator&#038;p=100034"},"modified":"2026-02-15T20:07:32","modified_gmt":"2026-02-15T20:07:32","slug":"belt-drive-calculator","status":"publish","type":"calculator","link":"https:\/\/vibromera.eu\/nb\/calculators\/belt-drive-calculator\/","title":{"rendered":"Beltedriftskalkulator | Beltelengde og senteravstand | Gratis onlineverkt\u00f8y"},"content":{"rendered":"\n<script type=\"application\/ld+json\">\n{\"@context\":\"https:\/\/schema.org\",\"@type\":\"WebApplication\",\"name\":\"Belt Drive Calculator\",\"alternateName\":[\"Belt Length Calculator\",\"Center Distance Calculator\",\"Pulley Calculator\"],\"description\":\"Free online belt drive calculator for belt length and center distance. Supports V-belt and flat belt drives.\",\"url\":\"https:\/\/vibromera.eu\/calculators\/belt-drive-calculator\/\",\"applicationCategory\":\"Engineering Calculator\",\"operatingSystem\":\"Any (Web Browser)\",\"offers\":{\"@type\":\"Offer\",\"price\":\"0\",\"priceCurrency\":\"EUR\"},\"creator\":{\"@type\":\"Organization\",\"name\":\"Vibromera\",\"url\":\"https:\/\/vibromera.eu\/\"},\"datePublished\":\"2024-01-01\",\"dateModified\":\"2025-02-14\",\"inLanguage\":\"en\",\"isAccessibleForFree\":true,\"featureList\":[\"Belt length calculation\",\"Center distance from belt length\",\"Wrap angle calculation\",\"Speed ratio\",\"Belt speed\",\"Auto-calculation\"],\"keywords\":\"belt drive, belt length, center distance, pulley, wrap angle\"}\n<\/script>\n\n<script type=\"application\/ld+json\">\n{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[\n{\"@type\":\"Question\",\"name\":\"How do I calculate belt length from pulley diameters and center distance?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Use the formula: L = 2C + \u03c0(D1+D2)\/2 + (D2\u2212D1)\u00b2\/(4C), where L is belt pitch length, C is center distance, D1 and D2 are pulley pitch diameters. This formula works for both V-belts and flat belts.\"}},\n{\"@type\":\"Question\",\"name\":\"How do I find center distance from a known belt length?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"The center distance can be found by solving the belt length equation: C = [B + \u221a(B\u00b2 \u2212 8(D2\u2212D1)\u00b2)] \/ 8, where B = 2L \u2212 \u03c0(D1+D2). This is the inverse calculation.\"}},\n{\"@type\":\"Question\",\"name\":\"What is the minimum wrap angle for belt drives?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"The minimum recommended wrap angle on the smaller pulley is 120\u00b0 for V-belts and 150\u00b0 for flat belts. Below these values, belt slip increases significantly and power capacity drops.\"}},\n{\"@type\":\"Question\",\"name\":\"How do I calculate belt speed?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Belt speed v = \u03c0 \u00d7 D \u00d7 n \/ 60000, where D is pulley diameter in mm and n is speed in RPM. Result is in m\/s. Maximum recommended belt speed is typically 25-30 m\/s for standard V-belts.\"}},\n{\"@type\":\"Question\",\"name\":\"What is the relationship between pulley diameters and speed ratio?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"The speed ratio equals the inverse ratio of pulley diameters: n2\/n1 = D1\/D2. A larger driven pulley means speed reduction. This assumes no belt slip (typically 1-2% for V-belts).\"}}\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\":\"Belt Drive Calculator\",\"item\":\"https:\/\/vibromera.eu\/calculators\/belt-drive-calculator\/\"}\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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class=\"vc-header-subtitle\">Calculate belt length from pulley diameters and center distance, or find center distance from a known belt length. Includes wrap angle, speed ratio, and belt speed.<\/p>\n    <div class=\"vc-badges\">\n        <span class=\"vc-badge\">Belt Length<\/span>\n        <span class=\"vc-badge\">Center Distance<\/span>\n        <span class=\"vc-badge\">Wrap Angle<\/span>\n    <\/div>\n<\/header>\n\n<div class=\"vc-card\">\n    <div class=\"vc-unit-bar\">\n        <button type=\"button\" class=\"vc-unit-btn vc-active\" data-mode=\"length\">Belt Length from C<\/button>\n        <button type=\"button\" class=\"vc-unit-btn\" data-mode=\"center\">Center Distance from L<\/button>\n    <\/div>\n\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-d1\">Small Pulley D\u2081 <span class=\"vc-label-hint\">(mm)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-d1\" inputmode=\"decimal\" step=\"any\" min=\"10\" placeholder=\"e.g. 100\" value=\"100\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-d2\">Large Pulley D\u2082 <span class=\"vc-label-hint\">(mm)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-d2\" inputmode=\"decimal\" step=\"any\" min=\"10\" placeholder=\"e.g. 300\" value=\"300\">\n            <\/div>\n            <div class=\"vc-field\" id=\"vc-field-c\">\n                <label class=\"vc-label\" for=\"vc-center\">Center Distance C <span class=\"vc-label-hint\">(mm)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-center\" inputmode=\"decimal\" step=\"any\" min=\"1\" placeholder=\"e.g. 500\" value=\"500\">\n            <\/div>\n            <div class=\"vc-field\" id=\"vc-field-l\" style=\"display:none\">\n                <label class=\"vc-label\" for=\"vc-beltlen\">Belt Length L <span class=\"vc-label-hint\">(mm)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-beltlen\" inputmode=\"decimal\" step=\"any\" min=\"100\" placeholder=\"e.g. 1638\" value=\"1638\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-n1\">Driver Speed <span class=\"vc-label-hint\">(RPM, optional)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-n1\" inputmode=\"decimal\" step=\"any\" min=\"0\" placeholder=\"e.g. 1500\" value=\"1500\">\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-d1=\"100\" data-d2=\"300\" data-c=\"500\" data-n=\"1500\">100\/300 mm, C=500<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-d1=\"150\" data-d2=\"450\" data-c=\"700\" data-n=\"1000\">150\/450 mm, C=700<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-d1=\"200\" data-d2=\"200\" data-c=\"600\" data-n=\"1500\">200\/200 mm, C=600 (1:1)<\/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\"><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\" id=\"vc-r-main-label\">Belt Length<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-main\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Wrap Angle (small pulley)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-wrap\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Speed Ratio<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-ratio\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Belt Speed<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-speed\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Driven Speed<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-n2\">\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; Formulas<\/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>Belt Length Formula<\/h3>\n            <div class=\"vc-formula-box\" id=\"vc-katex-1\"><\/div>\n            <h3>Center Distance from Belt Length<\/h3>\n            <div class=\"vc-formula-box\" id=\"vc-katex-2\"><\/div>\n            <h3>Wrap Angle<\/h3>\n            <div class=\"vc-formula-box\" id=\"vc-katex-3\"><\/div>\n            <div class=\"vc-warning-box\"><p style=\"margin:0;font-size:14px;color:var(--vc-ink-secondary)\"><strong>\u26a0\ufe0f Note:<\/strong> Minimum wrap angle on the small pulley should be \u2265120\u00b0 for V-belts. If below this, use an idler pulley or increase center distance.<\/p><\/div>\n            <div class=\"vc-example-box\">\n                <div class=\"vc-example-title\">Example<\/div>\n                <p><strong>Given:<\/strong> D\u2081=100 mm, D\u2082=300 mm, C=500 mm<\/p>\n                <p>L = 2\u00d7500 + \u03c0(100+300)\/2 + (300-100)\u00b2\/(4\u00d7500)<\/p>\n                <p>L = 1000 + 628.3 + 20 = <strong>1648.3 mm<\/strong><\/p>\n            <\/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\/v-belt-calculator\/\">V-Belt Selection Calculator<\/a>\n        <a class=\"vc-related-link\" href=\"\/calculators\/timing-belt-calculator\/\">Timing Belt Calculator<\/a>\n        <a class=\"vc-related-link\" href=\"\/calculators\/gear-ratio-calculator\/\">Gear Ratio Calculator<\/a>\n        <a class=\"vc-related-link\" href=\"\/calculators\/chain-drive-calculator\/\">Chain Drive Calculator<\/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 field balancing instruments and software. 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\u20132025 <a href=\"https:\/\/vibromera.eu\/\">Vibromera<\/a> \u2014 Engineering Calculators<\/p><p style=\"font-size:12px;margin-top:4px;\">Last updated: February 2025<\/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\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    var SLUG='belt-drive-calculator',mode='length';\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 D1=parseFloat($('vc-d1').value);\n        var D2=parseFloat($('vc-d2').value);\n        var n1=parseFloat($('vc-n1').value)||0;\n        if(!D1||D1<=0||!D2||D2<=0){$('vc-results').classList.remove('vc-visible');return}\n        \/\/ Ensure D2>=D1\n        var Ds=Math.min(D1,D2),Dl=Math.max(D1,D2);\n        var L,C;\n\n        if(mode==='length'){\n            C=parseFloat($('vc-center').value);\n            if(!C||C<=0){$('vc-results').classList.remove('vc-visible');return}\n            L=2*C+Math.PI*(Ds+Dl)\/2+Math.pow(Dl-Ds,2)\/(4*C);\n            $('vc-r-main-label').textContent='Belt Length';\n            $('vc-r-main').innerHTML=fmt(L,1)+' <span class=\"vc-rcard-unit\">mm<\/span>';\n        } else {\n            L=parseFloat($('vc-beltlen').value);\n            if(!L||L<=0){$('vc-results').classList.remove('vc-visible');return}\n            var B=2*L-Math.PI*(Ds+Dl);\n            var disc=B*B-8*Math.pow(Dl-Ds,2);\n            if(disc<0){$('vc-results').classList.remove('vc-visible');return}\n            C=(B+Math.sqrt(disc))\/8;\n            $('vc-r-main-label').textContent='Center Distance';\n            $('vc-r-main').innerHTML=fmt(C,1)+' <span class=\"vc-rcard-unit\">mm<\/span>';\n        }\n\n        \/\/ Wrap angle on small pulley\n        var wrapRad=Math.PI-2*Math.asin((Dl-Ds)\/(2*C));\n        var wrapDeg=wrapRad*180\/Math.PI;\n        var wrapColor=wrapDeg>=120?'color:var(--vc-green)':'color:var(--vc-red)';\n        $('vc-r-wrap').innerHTML='<span style=\"'+wrapColor+'\">'+fmt(wrapDeg,1)+'\u00b0<\/span>'+\n            (wrapDeg<120?' <span class=\"vc-rcard-unit\" style=\"color:var(--vc-red)\">\u26a0 Low<\/span>':' <span class=\"vc-rcard-unit\" style=\"color:var(--vc-green)\">\u2713 OK<\/span>');\n\n        var ratio=Dl\/Ds;\n        $('vc-r-ratio').innerHTML=fmt(ratio,3)+' <span class=\"vc-rcard-unit\">: 1<\/span>';\n\n        if(n1>0){\n            var v=Math.PI*D1*n1\/60000; \/\/ m\/s\n            var n2=n1*D1\/D2;\n            $('vc-r-speed').innerHTML=fmt(v,2)+' <span class=\"vc-rcard-unit\">m\/s<\/span>';\n            $('vc-r-n2').innerHTML=fmt(n2,1)+' <span class=\"vc-rcard-unit\">RPM<\/span>';\n        } else {\n            $('vc-r-speed').innerHTML='\u2014';\n            $('vc-r-n2').innerHTML='\u2014';\n        }\n\n        $('vc-results').classList.add('vc-visible');\n    }\n\n    document.querySelectorAll('.vc-unit-btn').forEach(function(btn){\n        btn.addEventListener('click',function(){\n            document.querySelectorAll('.vc-unit-btn').forEach(function(b){b.classList.remove('vc-active')});\n            this.classList.add('vc-active');\n            mode=this.getAttribute('data-mode');\n            $('vc-field-c').style.display=mode==='length'?'':'none';\n            $('vc-field-l').style.display=mode==='center'?'':'none';\n            calculate();\n        });\n    });\n\n    document.querySelectorAll('.vc-preset-btn').forEach(function(btn){\n        btn.addEventListener('click',function(e){\n            e.preventDefault();\n            mode='length';\n            document.querySelectorAll('.vc-unit-btn').forEach(function(b){b.classList.toggle('vc-active',b.getAttribute('data-mode')==='length')});\n            $('vc-field-c').style.display='';$('vc-field-l').style.display='none';\n            $('vc-d1').value=this.getAttribute('data-d1');\n            $('vc-d2').value=this.getAttribute('data-d2');\n            $('vc-center').value=this.getAttribute('data-c');\n            $('vc-n1').value=this.getAttribute('data-n');\n            calculate();\n        });\n    });\n\n    $('vc-form').addEventListener('input',calculate);\n    $('vc-form').addEventListener('change',calculate);\n\n    $('vc-copy-btn').addEventListener('click',function(){\n        var text='Belt Drive Calculation\\n\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\\n'+$('vc-r-main-label').textContent+': '+$('vc-r-main').textContent+'\\nWrap Angle: '+$('vc-r-wrap').textContent+'\\nSpeed Ratio: '+$('vc-r-ratio').textContent+'\\nBelt Speed: '+$('vc-r-speed').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\/calculators\/'+SLUG+'\/';\n        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\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:'How do I calculate belt length from pulley diameters and center distance?',a:'<p>Use: L = 2C + \u03c0(D\u2081+D\u2082)\/2 + (D\u2082\u2212D\u2081)\u00b2\/(4C). This gives the pitch length of the belt. For standard V-belts, select the nearest standard belt length.<\/p>'},\n        {q:'How do I find center distance from a known belt length?',a:'<p>Calculate B = 2L \u2212 \u03c0(D\u2081+D\u2082), then C = [B + \u221a(B\u00b2 \u2212 8(D\u2082\u2212D\u2081)\u00b2)] \/ 8. This is the inverse of the belt length formula.<\/p>'},\n        {q:'What is the minimum wrap angle for belt drives?',a:'<p>Minimum recommended: 120\u00b0 for V-belts, 150\u00b0 for flat belts. Below these values, belt slip increases significantly. Use an idler pulley or increase center distance if needed.<\/p>'},\n        {q:'How do I calculate belt speed?',a:'<p>Belt speed v = \u03c0 \u00d7 D \u00d7 n \/ 60000 (m\/s). Maximum recommended: 25\u201330 m\/s for standard V-belts, up to 60 m\/s for narrow V-belts.<\/p>'},\n        {q:'What is the relationship between pulley diameters and speed ratio?',a:'<p>Speed ratio = D\u2081\/D\u2082 (inverse of diameter ratio). Larger driven pulley = lower output speed. Belt slip is typically 1\u20132% for V-belts.<\/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(){\n        try{\n            katex.render('L = 2C + \\\\frac{\\\\pi(D_1+D_2)}{2} + \\\\frac{(D_2-D_1)^2}{4C}',$('vc-katex-1'),{displayMode:true,throwOnError:false});\n            katex.render('C = \\\\frac{B + \\\\sqrt{B^2 - 8(D_2-D_1)^2}}{8}, \\\\quad B = 2L - \\\\pi(D_1+D_2)',$('vc-katex-2'),{displayMode:true,throwOnError:false});\n            katex.render('\\\\alpha = 180\u00b0 - 2\\\\arcsin\\\\!\\\\left(\\\\frac{D_2-D_1}{2C}\\\\right)',$('vc-katex-3'),{displayMode:true,throwOnError:false});\n        }catch(e){}\n    }\n\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>Gratis kalkulator for remdrift p\u00e5 nett. Beregn remlengden fra remskivediametere og senteravstand, eller finn senteravstanden fra remlengden. L=2C+\u03c0(D1+D2)\/2+(D2-D1)\u00b2\/(4C).<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[],"tags":[],"class_list":["post-100034","calculator","type-calculator","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/nb\/wp-json\/wp\/v2\/calculator\/100034","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vibromera.eu\/nb\/wp-json\/wp\/v2\/calculator"}],"about":[{"href":"https:\/\/vibromera.eu\/nb\/wp-json\/wp\/v2\/types\/calculator"}],"version-history":[{"count":1,"href":"https:\/\/vibromera.eu\/nb\/wp-json\/wp\/v2\/calculator\/100034\/revisions"}],"predecessor-version":[{"id":100345,"href":"https:\/\/vibromera.eu\/nb\/wp-json\/wp\/v2\/calculator\/100034\/revisions\/100345"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/nb\/wp-json\/wp\/v2\/media?parent=100034"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/nb\/wp-json\/wp\/v2\/categories?post=100034"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/nb\/wp-json\/wp\/v2\/tags?post=100034"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}