{"id":100179,"date":"2026-02-15T20:25:20","date_gmt":"2026-02-15T20:25:20","guid":{"rendered":"https:\/\/vibromera.eu\/?post_type=calculator&#038;p=100179"},"modified":"2026-02-15T20:25:20","modified_gmt":"2026-02-15T20:25:20","slug":"orifice-flow-calculator-iso5167","status":"publish","type":"calculator","link":"https:\/\/vibromera.eu\/bn\/calculators\/orifice-flow-calculator-iso5167\/","title":{"rendered":"Orifice Plate Flow Calculator ISO 5167 | Free Online Tool"},"content":{"rendered":"\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"WebApplication\",\"name\":\"Orifice Plate Flow Calculator ISO 5167\",\"description\":\"Free online orifice plate flow calculator per ISO 5167.\",\"url\":\"https:\/\/vibromera.eu\/calculators\/orifice-flow-calculator-iso5167\/\",\"applicationCategory\":\"Engineering Calculator\",\"operatingSystem\":\"Any\",\"offers\":{\"@type\":\"Offer\",\"price\":\"0\",\"priceCurrency\":\"EUR\"},\"creator\":{\"@type\":\"Organization\",\"name\":\"Vibromera\",\"url\":\"https:\/\/vibromera.eu\/\"},\"datePublished\":\"2024-01-01\",\"dateModified\":\"2025-06-15\",\"inLanguage\":\"en\",\"isAccessibleForFree\":true}<\/script>\n\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[\n{\"@type\":\"Question\",\"name\":\"How does an orifice plate flow meter work?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"An orifice plate creates a constriction in the pipe. The fluid speeds up through the orifice, causing a pressure drop (\u0394P). Flow rate is proportional to \u221a(\u0394P), calculated using Q=C\u00d7\u03b5\u00d7A\u00d7\u221a(2\u0394P\/\u03c1) per ISO 5167.\"}},\n{\"@type\":\"Question\",\"name\":\"What is the beta ratio?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Beta (\u03b2) = d\/D, the ratio of orifice bore diameter to pipe internal diameter. Typical range: 0.2 to 0.75. Higher beta = less pressure loss but lower accuracy.\"}},\n{\"@type\":\"Question\",\"name\":\"What is the discharge coefficient C?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"The discharge coefficient accounts for real fluid effects (vena contracta, friction). For ISO 5167 corner taps, C is calculated from the Reader-Harris\/Gallagher equation and is typically 0.59\u20130.62 for \u03b2 = 0.3\u20130.7.\"}},\n{\"@type\":\"Question\",\"name\":\"What is the expansibility factor \u03b5?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"\u03b5 (epsilon) accounts for gas compressibility. For liquids, \u03b5 = 1. For gases, \u03b5 < 1 and depends on the pressure ratio and the isentropic exponent (\u03ba). \u03b5 \u2248 1 for small \u0394P\/P ratios.\"}},\n{\"@type\":\"Question\",\"name\":\"What are the ISO 5167 requirements for straight pipe?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"ISO 5167 requires minimum straight pipe upstream (typically 10\u201344 D depending on fitting type and \u03b2) and 4\u20138 D downstream. Flow conditioners can reduce upstream requirements.\"}}\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\":\"Orifice Flow ISO 5167\",\"item\":\"https:\/\/vibromera.eu\/calculators\/orifice-flow-calculator-iso5167\/\"}]}<\/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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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}\n.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)}\n.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)}\n.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}\n@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}}\n<\/style>\n\n<div class=\"vc-calculator\" id=\"vc-orifice-flow\">\n\n<header class=\"vc-header\">\n    <p class=\"vc-header-eyebrow\">Free Engineering Tool \u2014 #152<\/p>\n    <h1 class=\"vc-header-title\">Orifice Plate Flow Calculator \u2014 ISO 5167<\/h1>\n    <p class=\"vc-header-subtitle\">Calculate flow rate through an orifice plate per ISO 5167. Enter orifice and pipe diameters, differential pressure, and fluid density.<\/p>\n    <div class=\"vc-badges\"><span class=\"vc-badge\">ISO 5167<\/span><span class=\"vc-badge\">Q = C\u00b7\u03b5\u00b7A\u00b7\u221a(2\u0394P\/\u03c1)<\/span><span class=\"vc-badge\">Liquids &amp; Gases<\/span><\/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\"><label class=\"vc-label\" for=\"vc-d\">Orifice Bore (d) <span class=\"vc-label-hint\">(mm)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-d\" inputmode=\"decimal\" step=\"any\" min=\"0.1\" value=\"50\"><\/div>\n            <div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-D\">Pipe ID (D) <span class=\"vc-label-hint\">(mm)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-D\" inputmode=\"decimal\" step=\"any\" min=\"0.1\" value=\"102.3\"><\/div>\n            <div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-dp\">Differential Pressure (\u0394P) <span class=\"vc-label-hint\">(kPa)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-dp\" inputmode=\"decimal\" step=\"any\" min=\"0\" value=\"25\"><\/div>\n            <div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-rho\">Fluid Density (\u03c1) <span class=\"vc-label-hint\">(kg\/m\u00b3)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-rho\" inputmode=\"decimal\" step=\"any\" min=\"0\" value=\"998\"><\/div>\n            <div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-eps\">Expansibility (\u03b5) <span class=\"vc-label-hint\">(1.0 for liquids)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-eps\" inputmode=\"decimal\" step=\"any\" min=\"0\" max=\"1\" value=\"1.0\"><\/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=\"50\" data-D=\"102.3\" data-dp=\"25\" data-rho=\"998\" data-e=\"1.0\">Water DN100 \u03b2=0.49<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-d=\"75\" data-D=\"154.1\" data-dp=\"15\" data-rho=\"998\" data-e=\"1.0\">Water DN150 \u03b2=0.49<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-d=\"30\" data-D=\"54.5\" data-dp=\"10\" data-rho=\"1.2\" data-e=\"0.98\">Air DN50 \u03b2=0.55<\/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\">Volume Flow Rate<\/div><div class=\"vc-rcard-value\" id=\"vc-r-q\">\u2014<\/div><\/div>\n            <div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Mass Flow Rate<\/div><div class=\"vc-rcard-value\" id=\"vc-r-m\">\u2014<\/div><\/div>\n            <div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Beta Ratio (\u03b2 = d\/D)<\/div><div class=\"vc-rcard-value\" id=\"vc-r-beta\">\u2014<\/div><\/div>\n            <div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Discharge Coefficient C<\/div><div class=\"vc-rcard-value\" id=\"vc-r-c\">\u2014<\/div><\/div>\n            <div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Orifice Velocity<\/div><div class=\"vc-rcard-value\" id=\"vc-r-v\">\u2014<\/div><\/div>\n            <div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Pipe Velocity<\/div><div class=\"vc-rcard-value\" id=\"vc-r-vp\">\u2014<\/div><\/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\"><div class=\"vc-section-inner vc-theory\">\n        <h3>ISO 5167 Orifice Flow Equation<\/h3>\n        <div class=\"vc-formula-box\" id=\"vc-katex-1\"><\/div>\n        <ul>\n            <li><strong>C<\/strong> \u2014 discharge coefficient (Reader-Harris\/Gallagher equation)<\/li>\n            <li><strong>\u03b5<\/strong> \u2014 expansibility factor (1.0 for incompressible liquids)<\/li>\n            <li><strong>\u03b2<\/strong> \u2014 diameter ratio d\/D<\/li>\n            <li><strong>\u0394P<\/strong> \u2014 differential pressure across orifice<\/li>\n            <li><strong>\u03c1<\/strong> \u2014 upstream fluid density<\/li>\n        <\/ul>\n        <h3>Simplified Discharge Coefficient<\/h3>\n        <p>For corner taps, C \u2248 0.5959 + 0.0312\u03b2\u00b2 \u2212 0.184\u03b2\u2078 (simplified Reader-Harris). For flange taps, add correction terms for pipe diameter.<\/p>\n        <div class=\"vc-warning-box\"><p style=\"margin:0;font-size:14px;color:var(--vc-ink-secondary);\"><strong>\u26a0\ufe0f Note:<\/strong> This calculator uses a simplified C estimation. For custody transfer metering, use the full Reader-Harris\/Gallagher equation with Reynolds number correction per ISO 5167-2.<\/p><\/div>\n    <\/div><\/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\/pipe-wall-thickness-pressure\/\">Pipe Wall Thickness<\/a>\n        <a class=\"vc-related-link\" href=\"\/calculators\/pump-head-power\/\">Pump Head &#038; Power<\/a>\n        <a class=\"vc-related-link\" href=\"\/calculators\/duct-pressure-loss\/\">Duct Pressure Loss<\/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 instruments. 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;\">Orifice flow per ISO 5167. Last updated: June 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<\/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    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 d=parseFloat($('vc-d').value); \/\/ mm\n        var D=parseFloat($('vc-D').value); \/\/ mm\n        var dp=parseFloat($('vc-dp').value); \/\/ kPa\n        var rho=parseFloat($('vc-rho').value);\n        var eps=parseFloat($('vc-eps').value)||1.0;\n        if(!d||d<=0||!D||D<=0||!dp||dp<0||!rho||rho<=0||d>=D){$('vc-results').classList.remove('vc-visible');return}\n\n        var beta=d\/D;\n        var dM=d\/1000; var DM=D\/1000; \/\/ meters\n        var dpPa=dp*1000; \/\/ Pa\n\n        \/\/ Simplified Reader-Harris for corner taps\n        var C=0.5959+0.0312*Math.pow(beta,2.1)-0.184*Math.pow(beta,8);\n        var A=Math.PI\/4*dM*dM;\n        var Apipe=Math.PI\/4*DM*DM;\n\n        \/\/ Q = C * eps * A \/ sqrt(1-beta^4) * sqrt(2*dp\/rho)\n        var Qm3s=C*eps*A\/Math.sqrt(1-Math.pow(beta,4))*Math.sqrt(2*dpPa\/rho);\n        var Qm3h=Qm3s*3600;\n        var Qlmin=Qm3s*60000;\n        var mDot=Qm3s*rho;\n        var vOrifice=Qm3s\/A;\n        var vPipe=Qm3s\/Apipe;\n\n        $('vc-r-q').innerHTML=fmt(Qm3h,2)+' <span class=\"vc-rcard-unit\">m\u00b3\/h<\/span> <span class=\"vc-rcard-unit\">('+fmt(Qlmin,1)+' L\/min)<\/span>';\n        $('vc-r-m').innerHTML=fmt(mDot,3)+' <span class=\"vc-rcard-unit\">kg\/s<\/span> <span class=\"vc-rcard-unit\">('+fmt(mDot*3600,1)+' kg\/h)<\/span>';\n        $('vc-r-beta').innerHTML=fmt(beta,4);\n        $('vc-r-c').innerHTML=fmt(C,4);\n        $('vc-r-v').innerHTML=fmt(vOrifice,2)+' <span class=\"vc-rcard-unit\">m\/s<\/span>';\n        $('vc-r-vp').innerHTML=fmt(vPipe,2)+' <span class=\"vc-rcard-unit\">m\/s<\/span>';\n        $('vc-results').classList.add('vc-visible');\n    }\n\n    document.querySelectorAll('.vc-preset-btn').forEach(function(btn){btn.addEventListener('click',function(e){e.preventDefault();$('vc-d').value=this.getAttribute('data-d');$('vc-D').value=this.getAttribute('data-D');$('vc-dp').value=this.getAttribute('data-dp');$('vc-rho').value=this.getAttribute('data-rho');$('vc-eps').value=this.getAttribute('data-e');calculate()})});\n\n    $('vc-form').addEventListener('input',calculate);$('vc-form').addEventListener('change',calculate);\n\n    $('vc-copy-btn').addEventListener('click',function(){var text='Orifice Flow (ISO 5167)\\n\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\\nd='+$('vc-d').value+' mm, D='+$('vc-D').value+' mm\\n\u0394P='+$('vc-dp').value+' kPa, \u03c1='+$('vc-rho').value+' kg\/m\u00b3\\nFlow: '+$('vc-r-q').textContent+'\\nMass: '+$('vc-r-m').textContent+'\\n\u03b2='+$('vc-r-beta').textContent+', C='+$('vc-r-c').textContent+'\\n\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\\nvibromera.eu';if(navigator.clipboard){navigator.clipboard.writeText(text).then(function(){var b=$('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\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 does an orifice plate flow meter work?',a:'<p>The orifice creates a constriction, increasing velocity and decreasing pressure. Flow is proportional to \u221a(\u0394P). ISO 5167 provides the standardized calculation method.<\/p>'},\n        {q:'What is the beta ratio?',a:'<p>\u03b2 = d\/D, the orifice-to-pipe diameter ratio. Typical range: 0.2\u20130.75. Higher \u03b2 = less permanent pressure loss but reduced measurement accuracy and turndown.<\/p>'},\n        {q:'What is the discharge coefficient?',a:'<p>C accounts for real-fluid effects (vena contracta, friction). For ISO 5167 orifices, C is 0.59\u20130.62 for \u03b2 = 0.3\u20130.7. Calculated by the Reader-Harris\/Gallagher equation.<\/p>'},\n        {q:'What is expansibility factor \u03b5?',a:'<p>\u03b5 corrects for gas compressibility. For liquids, \u03b5 = 1.0. For gases, \u03b5 depends on pressure ratio and \u03ba (isentropic exponent). \u03b5 \u2248 1 when \u0394P\/P\u2081 is small.<\/p>'},\n        {q:'What straight pipe does ISO 5167 require?',a:'<p>Upstream: 10\u201344D depending on fitting type and \u03b2. Downstream: 4\u20138D. Flow conditioners can reduce upstream requirements significantly.<\/p>'}\n    ];\n    var faqList=$('vc-faq-list');faqData.forEach(function(f){faqList.innerHTML+='<div class=\"vc-faq-item\"><button type=\"button\" class=\"vc-faq-q\"><span>'+f.q+'<\/span><svg class=\"vc-faq-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button><div class=\"vc-faq-a\"><div class=\"vc-faq-a-inner\">'+f.a+'<\/div><\/div><\/div>'});\n    faqList.addEventListener('click',function(e){var btn=e.target.closest('.vc-faq-q');if(!btn)return;btn.closest('.vc-faq-item').classList.toggle('vc-open')});\n\n    function renderFormulas(){try{katex.render('Q = \\\\frac{C \\\\cdot \\\\varepsilon}{\\\\sqrt{1-\\\\beta^4}} \\\\cdot \\\\frac{\\\\pi}{4}d^2 \\\\cdot \\\\sqrt{\\\\frac{2\\\\Delta P}{\\\\rho}}',$('vc-katex-1'),{displayMode:true,throwOnError:false})}catch(e){}}\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>Free orifice plate flow calculator per ISO 5167. Enter orifice diameter, pipe diameter, differential pressure, and fluid density. Q=C\u00d7\u03b5\u00d7A\u00d7\u221a(2\u0394P\/\u03c1).<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[],"tags":[],"class_list":["post-100179","calculator","type-calculator","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100179","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator"}],"about":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/types\/calculator"}],"version-history":[{"count":1,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100179\/revisions"}],"predecessor-version":[{"id":100494,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100179\/revisions\/100494"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/media?parent=100179"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/categories?post=100179"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/tags?post=100179"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}