{"id":100194,"date":"2026-02-15T20:26:05","date_gmt":"2026-02-15T20:26:05","guid":{"rendered":"https:\/\/vibromera.eu\/?post_type=calculator&#038;p=100194"},"modified":"2026-02-15T20:26:05","modified_gmt":"2026-02-15T20:26:05","slug":"press-fit-calculator","status":"publish","type":"calculator","link":"https:\/\/vibromera.eu\/sw\/calculators\/press-fit-calculator\/","title":{"rendered":"Press Fit \/ Interference Fit Calculator | Free Tool #076"},"content":{"rendered":"\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"WebApplication\",\"name\":\"Press Fit Calculator\",\"description\":\"Interference fit using Lame equations.\",\"url\":\"https:\/\/vibromera.eu\/calculators\/press-fit-calculator\/\",\"applicationCategory\":\"Engineering Calculator\",\"offers\":{\"@type\":\"Offer\",\"price\":\"0\",\"priceCurrency\":\"EUR\"},\"creator\":{\"@type\":\"Organization\",\"name\":\"Vibromera\"},\"datePublished\":\"2024-01-01\",\"dateModified\":\"2025-02-14\",\"inLanguage\":\"en\",\"isAccessibleForFree\":true}<\/script>\n\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[{\"@type\":\"Question\",\"name\":\"What is interference fit?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Shaft OD larger than hub bore. Assembly requires pressing or thermal expansion. Contact pressure provides grip.\"}},{\"@type\":\"Question\",\"name\":\"How is contact pressure calculated?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Using Lame thick cylinder theory for same-material fits.\"}},{\"@type\":\"Question\",\"name\":\"What friction coefficient?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Steel\/steel dry: 0.10-0.15. With oil: 0.05-0.08.\"}},{\"@type\":\"Question\",\"name\":\"Shrink vs press fit?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Shrink for large sizes or heavy interference. Press for small\/medium.\"}},{\"@type\":\"Question\",\"name\":\"Temperature effect?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Differential expansion changes interference based on CTE difference.\"}}]}<\/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\":\"Press Fit\",\"item\":\"https:\/\/vibromera.eu\/calculators\/press-fit-calculator\/\"}]}<\/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)}.vc-faq-a{max-height:0;overflow:hidden;transition:max-height .35s}.vc-faq-item.vc-open .vc-faq-a{max-height:1200px}.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}.vc-related{display:flex;flex-wrap:wrap;gap:10px;margin-top:16px}.vc-related-link{display:inline-block;padding:8px 16px;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}.vc-related-link:hover{border-color:var(--vc-accent);color:var(--vc-accent)}.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}.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-links{margin-top:8px;font-size:12px}.vc-footer-links a{margin:0 8px}@media print{.vc-section-body{max-height:none!important}.vc-results{max-height:none!important;padding:24px!important}.vc-copy-btn,.vc-presets,.vc-promo{display:none!important}}<\/style>\n\n<div class=\"vc-calculator\">\n<header class=\"vc-header\"><p class=\"vc-header-eyebrow\">Free Engineering Tool #076<\/p><h1 class=\"vc-header-title\">Press Fit \/ Interference Fit Calculator<\/h1><p class=\"vc-header-subtitle\">Calculate contact pressure, grip force, and grip torque for interference fits using Lam&eacute; equations. Enter shaft and hub dimensions and material properties.<\/p><div class=\"vc-badges\"><span class=\"vc-badge\">Lam&eacute; Equations<\/span><span class=\"vc-badge\">Grip Torque<\/span><span class=\"vc-badge\">Auto-Calc<\/span><\/div><\/header>\n<div class=\"vc-card\">\n<div class=\"vc-unit-bar\"><button type=\"button\" class=\"vc-unit-btn vc-active\" data-system=\"metric\">Metric (mm, MPa)<\/button><button type=\"button\" class=\"vc-unit-btn\" data-system=\"imperial\">Imperial (in, psi)<\/button><\/div>\n<form class=\"vc-form\" id=\"vc-form\" autocomplete=\"off\"><div class=\"vc-form-grid\">\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-ds\">Shaft OD <span class=\"vc-label-hint\" id=\"vc-dsu\">(mm)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-ds\" step=\"any\" value=\"50.05\"><\/div>\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-dh\">Hub Bore ID <span class=\"vc-label-hint\" id=\"vc-dhu\">(mm)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-dh\" step=\"any\" value=\"50\"><\/div>\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-Do\">Hub OD <span class=\"vc-label-hint\" id=\"vc-Dou\">(mm)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-Do\" step=\"any\" value=\"100\"><\/div>\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-L\">Fit Length <span class=\"vc-label-hint\" id=\"vc-Lu\">(mm)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-L\" step=\"any\" min=\"1\" value=\"60\"><\/div>\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-E\">Elastic Modulus E <span class=\"vc-label-hint\">(GPa)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-E\" step=\"any\" min=\"1\" value=\"210\"><\/div>\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-nu\">Poisson Ratio v<\/label><input class=\"vc-input\" type=\"number\" id=\"vc-nu\" step=\"any\" value=\"0.3\"><\/div>\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-mu\">Friction Coeff &mu;<\/label><input class=\"vc-input\" type=\"number\" id=\"vc-mu\" step=\"any\" value=\"0.12\"><\/div>\n<\/div>\n<div class=\"vc-presets\"><div class=\"vc-presets-label\">Quick presets<\/div>\n<button type=\"button\" class=\"vc-preset-btn\" data-ds=\"50.05\" data-dh=\"50\" data-Do=\"100\" data-L=\"60\">50H7\/p6 Hub=100<\/button>\n<button type=\"button\" class=\"vc-preset-btn\" data-ds=\"30.032\" data-dh=\"30\" data-Do=\"60\" data-L=\"40\">30H7\/p6 Hub=60<\/button>\n<button type=\"button\" class=\"vc-preset-btn\" data-ds=\"80.1\" data-dh=\"80\" data-Do=\"140\" data-L=\"80\">80H7\/s6 Hub=140<\/button>\n<\/div><\/form>\n<div class=\"vc-results\" id=\"vc-results\"><div class=\"vc-results-head\"><h2 class=\"vc-results-title\">Results<\/h2><button type=\"button\" class=\"vc-copy-btn\" id=\"vc-copy-btn\">Copy<\/button><\/div>\n<div class=\"vc-result-grid\">\n<div class=\"vc-rcard vc-rcard-primary\"><div class=\"vc-rcard-label\">Diametral Interference<\/div><div class=\"vc-rcard-value\" id=\"vc-r-delta\">&mdash;<\/div><\/div>\n<div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Contact Pressure<\/div><div class=\"vc-rcard-value\" id=\"vc-r-p\">&mdash;<\/div><\/div>\n<div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Axial Grip Force<\/div><div class=\"vc-rcard-value\" id=\"vc-r-F\">&mdash;<\/div><\/div>\n<div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Grip Torque<\/div><div class=\"vc-rcard-value\" id=\"vc-r-T\">&mdash;<\/div><\/div>\n<div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Hub Hoop Stress<\/div><div class=\"vc-rcard-value\" id=\"vc-r-sig\">&mdash;<\/div><\/div>\n<\/div>\n<div class=\"vc-viz\" id=\"vc-viz\" style=\"text-align:center;margin:16px 0 8px\"><\/div>\n<\/div><\/div>\n<div class=\"vc-section vc-open\"><button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"true\"><span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">&#x1F4D8;<\/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\"><div class=\"vc-section-inner vc-theory\">\n<h3>Contact Pressure (Lam&eacute;)<\/h3><div class=\"vc-formula-box\" id=\"vc-katex-1\"><\/div>\n<h3>Grip Force &amp; Torque<\/h3><div class=\"vc-formula-box\" id=\"vc-katex-2\"><\/div><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)\">Assumes same material for shaft and hub. For different materials, use general Lam&eacute; with separate E, &nu;.<\/p><\/div>\n<\/div><\/div><\/div>\n<div class=\"vc-section\"><button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">&#x1F517;<\/span><span class=\"vc-section-title\">Related<\/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><div class=\"vc-section-body\"><div class=\"vc-section-inner\"><div class=\"vc-related\"><a class=\"vc-related-link\" href=\"\/calculators\/shaft-diameter-torsion\/\">Shaft Diameter<\/a><a class=\"vc-related-link\" href=\"\/calculators\/keyway-calculator\/\">Keyway<\/a><a class=\"vc-related-link\" href=\"\/calculators\/spline-connection-calculator\/\">Spline<\/a><\/div><\/div><\/div><\/div>\n<div class=\"vc-section\"><button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">&#x2753;<\/span><span class=\"vc-section-title\">FAQ<\/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><div class=\"vc-section-body\"><div class=\"vc-section-inner\"><div class=\"vc-faq-list\" id=\"vc-faq-list\"><\/div><\/div><\/div><\/div>\n<div class=\"vc-promo\"><div class=\"vc-promo-text\"><strong>Vibromera<\/strong> &mdash; Portable Balancing &amp; Vibration Analysis.<\/div><a class=\"vc-promo-link\" href=\"https:\/\/vibromera.eu\/\" target=\"_blank\" rel=\"noopener\">Learn More<\/a><\/div>\n<footer class=\"vc-footer\"><p>&copy; 2024&ndash;2025 <a href=\"https:\/\/vibromera.eu\/\">Vibromera<\/a><\/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='press-fit-calculator',uS='metric';\nfunction $(id){return document.getElementById(id)}\nfunction fmt(n,d){if(isNaN(n)||!isFinite(n))return'\\u2014';return n.toFixed(d==null?2:d).replace(\/(\\.\\d*?)0+$\/,'$1').replace(\/\\.$\/,'')}\nfunction calc(){\n  var ds=parseFloat($('vc-ds').value),dh=parseFloat($('vc-dh').value),Do=parseFloat($('vc-Do').value),L=parseFloat($('vc-L').value),E=parseFloat($('vc-E').value),nu=parseFloat($('vc-nu').value),mu=parseFloat($('vc-mu').value);\n  if(!ds||!dh||ds<=dh||!Do||Do<=ds||!L||L<=0||!E){$('vc-results').classList.remove('vc-visible');return}\n  var dsMm=uS==='imperial'?ds*25.4:ds,dhMm=uS==='imperial'?dh*25.4:dh,DoMm=uS==='imperial'?Do*25.4:Do,Lmm=uS==='imperial'?L*25.4:L,Empa=uS==='imperial'?E*6894.76:E*1000;\n  var delta=dsMm-dhMm,d=dhMm;\n  var k=(DoMm*DoMm+d*d)\/(DoMm*DoMm-d*d);\n  var p=delta*Empa\/(d*(k+nu+(1-nu)));\n  var Fg=mu*p*Math.PI*d*Lmm;\n  var Tg=Fg*d\/2;\n  var sigH=p*(DoMm*DoMm+d*d)\/(DoMm*DoMm-d*d);\n  if(uS==='imperial'){$('vc-r-delta').innerHTML=fmt(delta\/25.4,4)+' <span class=\"vc-rcard-unit\">in<\/span>';$('vc-r-p').innerHTML=fmt(p*145.038,0)+' <span class=\"vc-rcard-unit\">psi<\/span>';$('vc-r-F').innerHTML=fmt(Fg*0.224809,0)+' <span class=\"vc-rcard-unit\">lbf<\/span>';$('vc-r-T').innerHTML=fmt(Tg*0.000738,1)+' <span class=\"vc-rcard-unit\">lbf\\u00B7ft<\/span>';$('vc-r-sig').innerHTML=fmt(sigH*145.038,0)+' <span class=\"vc-rcard-unit\">psi<\/span>'}\n  else{$('vc-r-delta').innerHTML=fmt(delta,3)+' <span class=\"vc-rcard-unit\">mm<\/span>';$('vc-r-p').innerHTML=fmt(p,1)+' <span class=\"vc-rcard-unit\">MPa<\/span>';$('vc-r-F').innerHTML=fmt(Fg\/1000,1)+' <span class=\"vc-rcard-unit\">kN<\/span>';$('vc-r-T').innerHTML=fmt(Tg\/1e6,2)+' <span class=\"vc-rcard-unit\">kN\\u00B7m<\/span>';$('vc-r-sig').innerHTML=fmt(sigH,1)+' <span class=\"vc-rcard-unit\">MPa<\/span>'}\n  $('vc-results').classList.add('vc-visible');\n  drawViz(dhMm,DoMm,delta,p);\n  sH({ds:ds,dh:dh,Do:Do,L:L,_summary:'d='+dh+' delta='+fmt(delta,3)+'mm'});\n}\nvar uB=document.querySelectorAll('.vc-unit-btn');uB.forEach(function(b){b.addEventListener('click',function(){uB.forEach(function(x){x.classList.remove('vc-active')});this.classList.add('vc-active');uS=this.getAttribute('data-system');['vc-dsu','vc-dhu','vc-Dou','vc-Lu'].forEach(function(id){$(id).textContent=uS==='imperial'?'(in)':'(mm)'});calc()})});\ndocument.querySelectorAll('.vc-preset-btn').forEach(function(b){b.addEventListener('click',function(e){e.preventDefault();$('vc-ds').value=this.getAttribute('data-ds');$('vc-dh').value=this.getAttribute('data-dh');$('vc-Do').value=this.getAttribute('data-Do');$('vc-L').value=this.getAttribute('data-L');calc()})});\n$('vc-form').addEventListener('input',calc);$('vc-form').addEventListener('change',calc);\n$('vc-copy-btn').addEventListener('click',function(){var t='Press Fit\\nInterference: '+$('vc-r-delta').textContent+'\\nPressure: '+$('vc-r-p').textContent+'\\nGrip Force: '+$('vc-r-F').textContent+'\\nGrip Torque: '+$('vc-r-T').textContent;if(navigator.clipboard){navigator.clipboard.writeText(t).then(function(){var b=$('vc-copy-btn');b.classList.add('vc-copied');b.textContent='Copied!';setTimeout(function(){b.classList.remove('vc-copied');b.textContent='Copy'},2000)})}});\ndocument.querySelectorAll('.vc-section-toggle').forEach(function(b){b.addEventListener('click',function(){var s=this.closest('.vc-section');s.classList.toggle('vc-open');this.setAttribute('aria-expanded',s.classList.contains('vc-open'))})});\nvar fD=[{q:'What is interference fit?',a:'<p>Shaft OD > hub bore. Press or heat to assemble. Contact pressure provides grip.<\/p>'},{q:'How is pressure calculated?',a:'<p>Lam\\u00E9 thick cylinder theory for same-material fit.<\/p>'},{q:'Friction coefficient?',a:'<p>Steel dry: 0.10\\u20130.15. Oil: 0.05\\u20130.08. Clean: 0.15\\u20130.20.<\/p>'},{q:'Shrink vs press fit?',a:'<p>Shrink for large sizes. Press for small\/medium.<\/p>'},{q:'Temperature effect?',a:'<p>\\u0394\\u03B4 = d\\u00B7\\u0394T\\u00B7(\\u03B1hub\\u2212\\u03B1shaft). Check at operating temp.<\/p>'}];\nvar fL=$('vc-faq-list');fD.forEach(function(f){fL.innerHTML+='<div class=\"vc-faq-item\"><button type=\"button\" class=\"vc-faq-q\"><span>'+f.q+'<\/span><svg class=\"vc-faq-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button><div class=\"vc-faq-a\"><div class=\"vc-faq-a-inner\">'+f.a+'<\/div><\/div><\/div>'});\nfL.addEventListener('click',function(e){var b=e.target.closest('.vc-faq-q');if(b)b.closest('.vc-faq-item').classList.toggle('vc-open')});\nfunction drawViz(dh,Do,delta,p){\n  var c=$('vc-viz'),W=300,H=260;\n  var svg='<svg width=\"'+W+'\" height=\"'+H+'\" viewBox=\"0 0 '+W+' '+H+'\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">';\n  svg+='<defs><marker id=\"pfa\" markerWidth=\"6\" markerHeight=\"4\" refX=\"5\" refY=\"2\" orient=\"auto\"><path d=\"M0,0 L6,2 L0,4\" fill=\"#e74c3c\"\/><\/marker><\/defs>';\n  var cx=W\/2,cy=H\/2;\n  var maxD=Do;\n  var scale=80\/maxD;\n  var rHub=Do*scale,rShaft=dh*scale\/2;\n  rHub=Math.max(rHub,rShaft+15);\n  \/\/ Hub (outer circle)\n  svg+='<circle cx=\"'+cx+'\" cy=\"'+cy+'\" r=\"'+rHub+'\" fill=\"#e0e7ef\" stroke=\"#7b8fa3\" stroke-width=\"2\"\/>';\n  \/\/ Hub bore (dashed)\n  svg+='<circle cx=\"'+cx+'\" cy=\"'+cy+'\" r=\"'+rShaft+'\" fill=\"none\" stroke=\"#7b8fa3\" stroke-width=\"1\" stroke-dasharray=\"4,3\"\/>';\n  \/\/ Shaft (solid, slightly larger for interference)\n  var intVis=Math.max(2,Math.min(8,delta*scale*20));\n  svg+='<circle cx=\"'+cx+'\" cy=\"'+cy+'\" r=\"'+(rShaft+intVis\/2)+'\" fill=\"rgba(212,230,249,0.7)\" stroke=\"#3578b2\" stroke-width=\"2\"\/>';\n  \/\/ Interference arrows (radial, pointing inward at hub)\n  var nArr=8;\n  for(var i=0;i<nArr;i++){\n    var ang=i*2*Math.PI\/nArr;\n    var x1=cx+Math.cos(ang)*(rShaft+intVis+12);\n    var y1=cy+Math.sin(ang)*(rShaft+intVis+12);\n    var x2=cx+Math.cos(ang)*(rShaft+intVis+3);\n    var y2=cy+Math.sin(ang)*(rShaft+intVis+3);\n    svg+='<line x1=\"'+x1.toFixed(1)+'\" y1=\"'+y1.toFixed(1)+'\" x2=\"'+x2.toFixed(1)+'\" y2=\"'+y2.toFixed(1)+'\" stroke=\"#e74c3c\" stroke-width=\"1.2\" marker-end=\"url(#pfa)\"\/>';\n  }\n  \/\/ Labels\n  svg+='<text x=\"'+cx+'\" y=\"'+(cy+4)+'\" text-anchor=\"middle\" fill=\"#3578b2\" font-size=\"10\" font-weight=\"600\">Shaft<\/text>';\n  svg+='<text x=\"'+cx+'\" y=\"'+(cy-rHub+rShaft)\/2+'\" text-anchor=\"middle\" fill=\"#7b8fa3\" font-size=\"10\" dominant-baseline=\"middle\">Hub<\/text>';\n  svg+='<text x=\"'+cx+'\" y=\"16\" text-anchor=\"middle\" fill=\"#2c3e50\" font-size=\"11\" font-weight=\"600\">Interference: '+delta.toFixed(3)+' mm<\/text>';\n  svg+='<text x=\"'+cx+'\" y=\"'+(H-6)+'\" text-anchor=\"middle\" fill=\"#8a857e\" font-size=\"9\">Contact pressure p = '+p.toFixed(1)+' MPa<\/text>';\n  \/\/ Diameter labels\n  svg+='<text x=\"'+(cx+rHub+6)+'\" y=\"'+(cy+14)+'\" fill=\"#7b8fa3\" font-size=\"9\">D\\u2092='+Math.round(Do)+'<\/text>';\n  svg+='<text x=\"'+(cx+rShaft+6)+'\" y=\"'+(cy-6)+'\" fill=\"#3578b2\" font-size=\"9\">d='+Math.round(dh)+'<\/text>';\n  svg+='<\/svg>';\n  c.innerHTML=svg;\n}\nfunction sH(e){var k='vc_history_'+SLUG,a=[];try{a=JSON.parse(localStorage.getItem(k))||[]}catch(x){}e._ts=new Date().toISOString();a.unshift(e);if(a.length>10)a=a.slice(0,10);try{localStorage.setItem(k,JSON.stringify(a))}catch(x){}}\nfunction rF(){try{katex.render('p=\\\\frac{\\\\delta}{d\\\\left(\\\\frac{D_o^2+d^2}{D_o^2-d^2}+\\\\nu\\\\right)\/E+(1-\\\\nu)\/E}',$('vc-katex-1'),{displayMode:true,throwOnError:false});katex.render('F_{grip}=\\\\mu\\\\cdot p\\\\cdot\\\\pi\\\\cdot d\\\\cdot L',$('vc-katex-2'),{displayMode:true,throwOnError:false});katex.render('T_{grip}=F_{grip}\\\\cdot\\\\frac{d}{2}',$('vc-katex-3'),{displayMode:true,throwOnError:false})}catch(e){}}\nrF();calc();\n})();\n<\/script>\n","protected":false},"excerpt":{"rendered":"<p>Interference fit calculator using Lame equations. Calculate contact pressure, grip force, and grip torque from shaft OD, hub ID\/OD, length, material properties.<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[],"tags":[],"class_list":["post-100194","calculator","type-calculator","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/sw\/wp-json\/wp\/v2\/calculator\/100194","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vibromera.eu\/sw\/wp-json\/wp\/v2\/calculator"}],"about":[{"href":"https:\/\/vibromera.eu\/sw\/wp-json\/wp\/v2\/types\/calculator"}],"version-history":[{"count":1,"href":"https:\/\/vibromera.eu\/sw\/wp-json\/wp\/v2\/calculator\/100194\/revisions"}],"predecessor-version":[{"id":100509,"href":"https:\/\/vibromera.eu\/sw\/wp-json\/wp\/v2\/calculator\/100194\/revisions\/100509"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/sw\/wp-json\/wp\/v2\/media?parent=100194"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/sw\/wp-json\/wp\/v2\/categories?post=100194"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/sw\/wp-json\/wp\/v2\/tags?post=100194"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}