{"id":100188,"date":"2026-02-15T20:25:47","date_gmt":"2026-02-15T20:25:47","guid":{"rendered":"https:\/\/vibromera.eu\/?post_type=calculator&#038;p=100188"},"modified":"2026-07-13T03:09:40","modified_gmt":"2026-07-13T03:09:40","slug":"pipe-wall-thickness-pressure","status":"publish","type":"calculator","link":"https:\/\/vibromera.eu\/fi\/calculators\/pipe-wall-thickness-pressure\/","title":{"rendered":"Thin-Wall Internal-Pressure Screening Arithmetic"},"content":{"rendered":"\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"WebApplication\",\"name\":\"Thin-Wall Internal-Pressure Screening Arithmetic\",\"description\":\"Calculates ideal cylindrical hoop-membrane pressure wall and documented allowance\/tolerance arithmetic. It is not an ASME code thickness, schedule, MAWP or burst-pressure calculator.\",\"url\":\"https:\/\/vibromera.eu\/calculators\/pipe-wall-thickness-pressure\/\",\"applicationCategory\":\"EngineeringApplication\",\"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\":\"2026-07-13\",\"inLanguage\":\"en\",\"isAccessibleForFree\":true,\"featureList\":[\"Thin-wall hoop-membrane screening\",\"Inside-diameter basis\",\"Documented unavailable-wall allowance\",\"Documented negative manufacturing tolerance\",\"No schedule or code verdict\"],\"keywords\":\"thin wall cylinder,hoop membrane stress,pressure wall screening,controlled allowance\"}<\/script>\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[{\"@type\":\"Question\",\"name\":\"Is this an ASME B31.3 pipe-thickness calculation?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"No. It is general thin-wall membrane arithmetic. The complete current code, material data and project design basis are required for pressure design.\"}},{\"@type\":\"Question\",\"name\":\"Does the result select a pipe schedule?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"No. Product dimensions, tolerances, material condition and availability must come from the controlled product specification.\"}},{\"@type\":\"Question\",\"name\":\"Is the calculated pressure wall a burst thickness?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"No. The entered stress is a documented screening limit, not ultimate strength, and failure modes and code requirements are not modeled.\"}},{\"@type\":\"Question\",\"name\":\"Why is internal diameter required?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"The displayed force-equilibrium equation uses the internal radius at the assessed pressure-boundary state. Nominal DN or NPS is not an internal diameter.\"}}]}<\/script>\n<style>:root{--s:#fff;--sa:#f8f6f2;--i:#1a1a1a;--is:#5a5650;--im:#8a857e;--a:#8a3f2d;--al:#f9eee9;--b:#d9d4cc;--bl:#e8e4dd;--y:#8a6500;--yl:#fef9e8;--r:#a12b2b;--f:'DM Sans',sans-serif;--m:'JetBrains Mono',monospace;--d:'Fraunces',serif}.vc-calculator{font-family:var(--f);font-size:15px;line-height:1.65;color:var(--i);max-width:960px;margin:auto;padding:20px 16px 40px}.vc-calculator *{box-sizing:border-box}.vc-header{text-align:center;padding:48px 20px 40px;border-bottom:3px solid var(--a)}.vc-header-eyebrow{font:500 11px var(--m);letter-spacing:.15em;text-transform:uppercase;color:var(--a)}.vc-header-title{font:800 clamp(24px,4vw,36px)\/1.15 var(--d);margin:10px 0 14px}.vc-header-subtitle{max-width:760px;margin:auto;color:var(--is)}.vc-badges{display:flex;gap:8px;justify-content:center;flex-wrap:wrap;margin-top:18px}.vc-badge{font:500 11px var(--m);padding:4px 10px;border:1px solid var(--b);border-radius:4px}.vc-card,.vc-section{background:var(--s);border:1px solid var(--b);border-radius:12px;overflow:hidden;margin-top:28px}.vc-form{padding:24px}.vc-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px}.vc-field{display:flex;flex-direction:column}.vc-full{grid-column:1\/-1}.vc-label{font-size:12px;font-weight:600;letter-spacing:.04em;text-transform:uppercase;color:var(--is);margin-bottom:6px}.vc-hint{font-weight:400;text-transform:none;letter-spacing:0;color:var(--im)}.vc-input,.vc-select{width:100%;padding:10px 12px;border:1.5px solid var(--b);border-radius:6px;font:14px var(--f);background:var(--s)}.vc-pair{display:grid;grid-template-columns:2fr 1fr;gap:8px}.vc-check{display:flex;gap:10px;padding:12px;border:1px solid var(--bl);border-radius:6px;background:var(--sa);font-size:13px;color:var(--is)}.vc-check input{margin-top:4px}.vc-validation{min-height:22px;color:var(--r);font-size:13px;margin-top:10px}.vc-results{border-top:1px solid var(--bl);background:var(--sa);padding:0;max-height:0;overflow:hidden}.vc-results.vc-visible{max-height:1400px;padding:24px}.vc-result-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:12px}.vc-rcard{background:var(--s);border:1px solid var(--bl);border-radius:8px;padding:16px}.vc-primary{grid-column:1\/-1;border:2px solid var(--a);background:var(--al)}.vc-rcard-label{font:500 10px var(--m);letter-spacing:.1em;text-transform:uppercase;color:var(--im)}.vc-rcard-value{font:600 19px var(--m);overflow-wrap:anywhere}.vc-primary .vc-rcard-value{font-size:24px;color:var(--a)}.vc-status{grid-column:1\/-1;padding:12px;background:var(--yl);border-left:3px solid var(--y);font-size:13px;color:var(--is)}.vc-section-toggle{width:100%;display:flex;justify-content:space-between;padding:18px 24px;border:0;background:transparent;cursor:pointer;text-align:left}.vc-section-title{font:700 18px var(--d)}.vc-section-body{max-height:0;overflow:hidden}.vc-section.vc-open .vc-section-body{max-height:15000px}.vc-section-inner{padding:0 24px 24px;border-top:1px solid var(--bl)}.vc-theory h3{font:700 17px var(--d);margin:24px 0 8px}.vc-theory p,.vc-theory li{font-size:14px;color:var(--is)}.vc-formula{padding:14px;border:2px solid var(--b);border-radius:6px;background:var(--sa);text-align:center;font:500 14px var(--m);margin:12px 0}.vc-warning{padding:14px;background:var(--yl);border-left:3px solid var(--y);color:var(--is)}.vc-faq-item{border:1px solid var(--bl);margin-top:8px}.vc-faq-q{width:100%;padding:14px;border:0;background:var(--sa);text-align:left;font-weight:600}.vc-faq-a{display:none;padding:14px;color:var(--is)}.vc-faq-item.vc-open .vc-faq-a{display:block}.vc-footer{text-align:center;padding:30px;color:var(--im);font-size:13px}@media(max-width:600px){.vc-grid,.vc-result-grid{grid-template-columns:1fr}.vc-full,.vc-primary,.vc-status{grid-column:1}.vc-pair{grid-template-columns:1fr}}<\/style>\n<div class=\"vc-calculator\"><header class=\"vc-header\"><p class=\"vc-header-eyebrow\">General membrane mechanics \u2014 not code pressure design<\/p><h1 class=\"vc-header-title\">Thin-Wall Internal-Pressure Screening Arithmetic<\/h1><p class=\"vc-header-subtitle\">Calculate an ideal hoop-membrane pressure wall from a controlled inside diameter and documented effective stress limit, then apply a documented unavailable-wall allowance and negative manufacturing tolerance. No schedule, MAWP, burst pressure or code-compliance result is generated.<\/p><div class=\"vc-badges\"><span class=\"vc-badge\">Inside-diameter basis<\/span><span class=\"vc-badge\">Gauge-pressure difference<\/span><span class=\"vc-badge\">Thin wall only<\/span><span class=\"vc-badge\">No ASME verdict<\/span><\/div><\/header>\n<div class=\"vc-card\"><form class=\"vc-form\" id=\"vc-form\" autocomplete=\"off\" novalidate><div class=\"vc-grid\">\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-pressure\">Design pressure difference<\/label><div class=\"vc-pair\"><input class=\"vc-input\" id=\"vc-pressure\" inputmode=\"decimal\"><select class=\"vc-select\" id=\"vc-pressure-unit\"><option value=\"mpa\">MPa<\/option><option value=\"bar\">bar<\/option><option value=\"psi\">psi<\/option><\/select><\/div><\/div>\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-id\">Controlled inside diameter <span class=\"vc-hint\">at assessed state<\/span><\/label><div class=\"vc-pair\"><input class=\"vc-input\" id=\"vc-id\" inputmode=\"decimal\"><select class=\"vc-select\" id=\"vc-length-unit\"><option value=\"mm\">mm<\/option><option value=\"in\">in<\/option><\/select><\/div><\/div>\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-limit\">Documented effective hoop-stress limit<\/label><div class=\"vc-pair\"><input class=\"vc-input\" id=\"vc-limit\" inputmode=\"decimal\"><select class=\"vc-select\" id=\"vc-stress-unit\"><option value=\"mpa\">MPa<\/option><option value=\"ksi\">ksi<\/option><\/select><\/div><\/div>\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-allowance\">Documented unavailable-wall allowance c<\/label><input class=\"vc-input\" id=\"vc-allowance\" inputmode=\"decimal\" placeholder=\"0 allowed\"><\/div>\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-tolerance\">Documented maximum negative tolerance m <span class=\"vc-hint\">%<\/span><\/label><input class=\"vc-input\" id=\"vc-tolerance\" inputmode=\"decimal\" placeholder=\"0 allowed; must be <100\"><\/div>\n<div class=\"vc-field vc-full\"><label class=\"vc-label\" for=\"vc-source\">Controlled calculation-basis source<\/label><input class=\"vc-input\" id=\"vc-source\" type=\"text\" placeholder=\"pressure\/temperature case; actual ID state; material\/product\/condition; effective stress basis; allowance; tolerance; revisions\"><\/div>\n<div class=\"vc-field vc-full\"><label class=\"vc-check\" for=\"vc-gate\"><input id=\"vc-gate\" type=\"checkbox\"><span>The entered pressure is a differential gauge pressure; the inside diameter is for the assessed pressure-boundary state; the stress limit already incorporates every applicable material, temperature, weld\/joint-quality, life and design factor required by the controlling basis; c is the total documented wall unavailable to resist pressure; m is the applicable maximum negative tolerance. The component is a straight, isotropic, circular, thin-walled cylinder away from discontinuities.<\/span><\/label><\/div>\n<\/div><div class=\"vc-validation\" id=\"vc-validation\" role=\"status\" aria-live=\"polite\"><\/div><\/form>\n<div class=\"vc-results\" id=\"vc-results\"><div class=\"vc-result-grid\"><div class=\"vc-rcard vc-primary\"><div class=\"vc-rcard-label\">Arithmetic minimum nominal wall<\/div><div class=\"vc-rcard-value\" id=\"vc-r-nominal\">\u2014<\/div><\/div><div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Pressure-resisting wall tp<\/div><div class=\"vc-rcard-value\" id=\"vc-r-pressure\">\u2014<\/div><\/div><div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Minimum delivered wall tn(1\u2212m)<\/div><div class=\"vc-rcard-value\" id=\"vc-r-delivered\">\u2014<\/div><\/div><div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Thin-wall ratio tp\/ri<\/div><div class=\"vc-rcard-value\" id=\"vc-r-ratio\">\u2014<\/div><\/div><div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Ideal closed-end axial membrane stress<\/div><div class=\"vc-rcard-value\" id=\"vc-r-axial\">\u2014<\/div><\/div><div class=\"vc-status\" id=\"vc-r-note\">General arithmetic only.<\/div><\/div><\/div><\/div>\n<div class=\"vc-section vc-open\"><button class=\"vc-section-toggle\" type=\"button\" aria-expanded=\"true\"><span class=\"vc-section-title\">Equations, variables and boundaries<\/span><span>\u2304<\/span><\/button><div class=\"vc-section-body\"><div class=\"vc-section-inner vc-theory\"><div class=\"vc-formula\">\u03c3h=P\u00b7ri\/tp=P\u00b7Di\/(2tp) &nbsp;\u2192&nbsp; tp=P\u00b7Di\/(2\u03c3lim)<br>tn,min=(tp+c)\/(1\u2212m)<\/div><p>P is differential gauge pressure; Di and ri=Di\/2 are the controlled internal diameter\/radius at the assessed state; tp is effective wall resisting pressure; \u03c3lim is a documented permissible effective hoop-membrane stress; c is total unavailable wall; m is a decimal maximum negative manufacturing tolerance; tn,min is the arithmetic nominal wall before that tolerance. Pressure and stress must use the same units; all lengths must use the same units.<\/p><p>For an ideal closed-end thin cylinder, the axial pressure membrane stress at tp is \u03c3a=P\u00b7ri\/(2tp)=\u03c3lim\/2. The result does not include any other axial, bending, torsional, thermal, local or cyclic load.<\/p><h3>Applicability gate<\/h3><p>The calculator suppresses results when tp\/ri&gt;0.1. The public University of Illinois derivation treats the thin-wall approximation as sufficient at ri\/t\u226510 and explicitly states uniform through-wall stress and neglected radial stress. Passing this numerical screen does not establish code applicability.<\/p><div class=\"vc-warning\"><strong>Not a design or acceptance result.<\/strong> No external pressure\/buckling, transient\/surge, fatigue, creep, thermal gradient, weight, supports, vibration, seismic\/wind, ovality, defects, threading\/grooving, bends\/branches, weld reinforcement, stress concentration, fracture, test pressure, fabrication, inspection or uncertainty is evaluated.<\/div><h3>Standards boundary<\/h3><p><strong>ASME B31.3-2024<\/strong> is the current process-piping code record and covers materials, components, design, fabrication, assembly, erection, examination, inspection and testing. Its exact pressure-design equations, coefficient tables, allowable stresses and service rules are licensed content and are not reproduced here.<\/p><p><strong>ISO 4200:1991<\/strong> edition 4 is published and under review. It is a general table of dimensions and masses for plain-end welded\/seamless steel tubes, not a pressure-design approval. Product dimensions and tolerances must come from the selected controlled product specification.<\/p><p><strong>ASTM A106\/A106M-26<\/strong> is the current ASTM listing for seamless carbon-steel pipe for high-temperature service. The old universal 138 MPa, 12.5% and schedule claims have been removed; exact material\/tolerance\/product rows require the complete applicable standards.<\/p><div class=\"vc-warning\"><strong>NEEDS_LICENSED_SOURCE:<\/strong> selected-code equation and limits; S\/E\/W\/Y or equivalent factors; allowable-stress tables; material\/product tolerances; corrosion\/erosion\/mechanical allowances; schedule dimensions; MAWP, test and acceptance procedures.<\/div><h3>Sources<\/h3><p><a href=\"https:\/\/mechref.engr.illinois.edu\/sol\/pressure.html\" target=\"_blank\" rel=\"noopener\">University of Illinois thin-walled pressure vessels<\/a>; <a href=\"https:\/\/www.purdue.edu\/freeform\/me323\/wp-content\/uploads\/sites\/2\/2022\/08\/pressure_vessel.pdf\" target=\"_blank\" rel=\"noopener\">Purdue ME323 summary<\/a>; <a href=\"https:\/\/www.asme.org\/codes-standards\/find-codes-standards\/b31-3-process-piping\/2024\/pdf\" target=\"_blank\" rel=\"noopener\">ASME B31.3-2024 official record<\/a>; <a href=\"https:\/\/www.iso.org\/standard\/9985.html\" target=\"_blank\" rel=\"noopener\">ISO 4200:1991<\/a>; <a href=\"https:\/\/store.astm.org\/products-services\/standards-and-publications\/standards\/steel-standards.html\" target=\"_blank\" rel=\"noopener\">ASTM current steel-standards listing<\/a>; <a href=\"https:\/\/www.nist.gov\/pml\/special-publication-811\/nist-guide-si-appendix-b-conversion-factors\" target=\"_blank\" rel=\"noopener\">NIST conversion factors<\/a>.<\/p><\/div><\/div><\/div>\n<div class=\"vc-section\"><button class=\"vc-section-toggle\" type=\"button\" aria-expanded=\"false\"><span class=\"vc-section-title\">Frequently asked questions<\/span><span>\u2304<\/span><\/button><div class=\"vc-section-body\"><div class=\"vc-section-inner\"><div id=\"vc-faq-list\"><\/div><\/div><\/div><\/div><footer class=\"vc-footer\">\u00a9 2024\u20132026 Vibromera \u2014 reviewed 13 July 2026<\/footer><\/div>\n<script>(function(){'use strict';function $(id){return document.getElementById(id)}function read(raw,zero){var t=String(raw||'').trim();if(!t||(t.includes(',')&&t.includes('.')))return null;t=t.replace(',','.');if(!\/^(?:\\d+(?:\\.\\d*)?|\\.\\d+)$\/.test(t))return null;var v=Number(t);return Number.isFinite(v)&&(zero?v>=0:v>0)?v:null}function fmt(v){if(Math.abs(v)>=1e9||Math.abs(v)<1e-7)return v.toExponential(8);return Number(v.toPrecision(12)).toString()}function hide(m){$('vc-results').classList.remove('vc-visible');$('vc-validation').textContent=m||''}function calc(){var source=$('vc-source').value.trim();if(!source)return hide('Enter the controlled calculation-basis source.');if(!$('vc-gate').checked)return hide('Confirm the complete controlled basis and thin-cylinder applicability statement.');var P=read($('vc-pressure').value,false),Di=read($('vc-id').value,false),s=read($('vc-limit').value,false),c=read($('vc-allowance').value,true),pct=read($('vc-tolerance').value,true);if(P===null||Di===null||s===null||c===null||pct===null)return hide('Enter complete positive pressure,diameter and stress values;allowance and tolerance may be zero.');if(pct>=100)return hide('Negative manufacturing tolerance must be less than 100%.');var PSI=6894.757293168,IN=.0254;if($('vc-pressure-unit').value==='bar')P*=1e5;else if($('vc-pressure-unit').value==='psi')P*=PSI;else P*=1e6;if($('vc-length-unit').value==='in'){Di*=IN;c*=IN}else{Di*=.001;c*=.001}if($('vc-stress-unit').value==='ksi')s*=PSI*1000;else s*=1e6;var tp=P*Di\/(2*s),m=pct\/100,tn=(tp+c)\/(1-m),delivered=tn*(1-m),ratio=tp\/(Di\/2),axial=P*Di\/(4*tp);if(![tp,tn,delivered,ratio,axial].every(function(x){return Number.isFinite(x)&&x>=0}))return hide('Arithmetic did not produce finite non-negative results.');if(ratio>.1)return hide('The calculated tp\/ri exceeds 0.1;use an applicable thick-wall\/code analysis.');var outIn=$('vc-length-unit').value==='in';function length(v){return outIn?fmt(v\/IN)+' in | '+fmt(v*1000)+' mm':fmt(v*1000)+' mm | '+fmt(v\/IN)+' in'}$('vc-r-nominal').textContent=length(tn);$('vc-r-pressure').textContent=length(tp);$('vc-r-delivered').textContent=length(delivered);$('vc-r-ratio').textContent=fmt(ratio)+' | ri\/tp='+fmt(1\/ratio);$('vc-r-axial').textContent=fmt(axial\/1e6)+' MPa | '+fmt(axial\/(PSI*1000))+' ksi';$('vc-r-note').textContent='Ideal thin-wall membrane and documented allowance\/tolerance arithmetic only.No code compliance,schedule selection,MAWP,burst or safe-operation verdict.';$('vc-validation').textContent='';$('vc-results').classList.add('vc-visible')}$('vc-form').addEventListener('input',calc);$('vc-form').addEventListener('change',calc);document.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',String(s.classList.contains('vc-open')))})});var faq=[['Can I enter DN100 or NPS4 as the diameter?','No.Enter the controlled internal diameter at the assessed pressure-boundary state.Nominal designations are not actual internal diameters.'],['What stress value should I enter?','Only a documented effective hoop-membrane limit for the exact material,product,condition,temperature,joint quality,life and governing basis.Do not substitute yield or tensile strength without that basis.'],['Does a result mean the selected pipe is safe?','No.All omitted loads,failure modes,manufacturing rules,inspection,test and acceptance requirements still apply.'],['Why was the burst-pressure result removed?','The old code inserted its own calculated wall back into the same formula,so the displayed value merely reproduced the entered pressure.It was not a burst prediction.']];var l=$('vc-faq-list');faq.forEach(function(x){var w=document.createElement('div');w.className='vc-faq-item';var b=document.createElement('button');b.type='button';b.className='vc-faq-q';b.textContent=x[0];var a=document.createElement('div');a.className='vc-faq-a';a.textContent=x[1];w.appendChild(b);w.appendChild(a);l.appendChild(w)});l.addEventListener('click',function(e){var b=e.target.closest('.vc-faq-q');if(b)b.closest('.vc-faq-item').classList.toggle('vc-open')});hide('')})();<\/script>\n","protected":false},"excerpt":{"rendered":"<p>General thin-cylinder hoop-membrane and documented allowance\/tolerance arithmetic without a pipe schedule,MAWP,burst-pressure or code-compliance verdict.<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[],"tags":[],"class_list":["post-100188","calculator","type-calculator","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/fi\/wp-json\/wp\/v2\/calculator\/100188","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vibromera.eu\/fi\/wp-json\/wp\/v2\/calculator"}],"about":[{"href":"https:\/\/vibromera.eu\/fi\/wp-json\/wp\/v2\/types\/calculator"}],"version-history":[{"count":3,"href":"https:\/\/vibromera.eu\/fi\/wp-json\/wp\/v2\/calculator\/100188\/revisions"}],"predecessor-version":[{"id":102526,"href":"https:\/\/vibromera.eu\/fi\/wp-json\/wp\/v2\/calculator\/100188\/revisions\/102526"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/fi\/wp-json\/wp\/v2\/media?parent=100188"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/fi\/wp-json\/wp\/v2\/categories?post=100188"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/fi\/wp-json\/wp\/v2\/tags?post=100188"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}