{"id":1258,"date":"2025-05-07T10:56:29","date_gmt":"2025-05-07T02:56:29","guid":{"rendered":"https:\/\/hengoseal.com\/?p=1258"},"modified":"2025-05-07T10:56:29","modified_gmt":"2025-05-07T02:56:29","slug":"hydraulic-seal-stack-design","status":"publish","type":"post","link":"https:\/\/hengoseal.com\/el\/hydraulic-seal-stack-design\/","title":{"rendered":"Hydraulic Seal Stack Design: How to Build the Perfect Sealing System for Your Cylinder in 2025"},"content":{"rendered":"<p>Sealing just one part of your hydraulic cylinder isn\u2019t enough. To prevent leakage, absorb shocks, and reduce downtime\u2014you need a complete <strong>seal stack<\/strong>.<\/p>\n<p>A hydraulic seal stack is a strategic combination of rod, piston, buffer, and wiper seals. When built correctly, it ensures your system performs under pressure, lasts longer, and leaks less.<\/p>\n<p><img decoding=\"async\" src=\"http:\/\/hengoseal.com\/wp-content\/uploads\/2025\/05\/hydraulic-o-ring-kits.jpg\" alt=\"placeholder_image\" \/><\/p>\n<p>In this 2025 guide, I\u2019ll walk you through how to build the perfect seal stack for your hydraulic cylinders.<\/p>\n<h2>What is a hydraulic seal stack?<\/h2>\n<p>A seal stack is a layered arrangement of different seal types in one cylinder\u2014each handling a specific role:<\/p>\n<ul>\n<li><strong>\u03a4\u03c3\u03b9\u03bc\u03bf\u03cd\u03c7\u03b5\u03c2 \u03c1\u03ac\u03b2\u03b4\u03c9\u03bd<\/strong> to block fluid from exiting<\/li>\n<li><strong>\u03a4\u03c3\u03b9\u03bc\u03bf\u03cd\u03c7\u03b5\u03c2 \u03b5\u03bc\u03b2\u03cc\u03bb\u03bf\u03c5<\/strong> to divide pressure chambers<\/li>\n<li><strong>\u03a3\u03c6\u03c1\u03b1\u03b3\u03af\u03b4\u03b5\u03c2 \u03c1\u03c5\u03b8\u03bc\u03b9\u03c3\u03c4\u03b9\u03ba\u03bf\u03cd<\/strong> to absorb shocks and prevent extrusion<\/li>\n<li><strong>Wipers<\/strong> to keep contaminants out<\/li>\n<li><strong>Guide rings<\/strong> to ensure alignment and prevent side loading<\/li>\n<\/ul>\n<p><img decoding=\"async\" src=\"http:\/\/hengoseal.com\/wp-content\/uploads\/2025\/05\/ChatGPT-Image-2025\u5e744\u670816\u65e5-13_54_28.png\" alt=\"placeholder_image\" \/><\/p>\n<p>At Hengoseal, we often combine <a href=\"https:\/\/hengoseal.com\/el\/product\/un-hydraulic-seal\/\" target=\"_blank\">\u03a3\u03c6\u03c1\u03b1\u03b3\u03af\u03b4\u03b5\u03c2 \u03c1\u03ac\u03b2\u03b4\u03c9\u03bd \u039f\u0397\u0395<\/a>, <a href=\"https:\/\/hengoseal.com\/el\/product\/idu-odu-piston-seal\/\" target=\"_blank\">IDU\/ODU piston seals<\/a>, \u03ba\u03b1\u03b9 <a href=\"https:\/\/hengoseal.com\/el\/product\/kdas-compact-seal\/\" target=\"_blank\">KDAS buffer seals<\/a> in a single cylinder for optimal sealing.<\/p>\n<h2>Which seals should be included in a standard cylinder?<\/h2>\n<p>Here\u2019s a typical seal stack layout for a double-acting hydraulic cylinder:<\/p>\n<table>\n<thead>\n<tr>\n<th>\u0398\u03ad\u03c3\u03b7<\/th>\n<th>\u03a4\u03cd\u03c0\u03bf\u03c2 \u03c3\u03c6\u03c1\u03b1\u03b3\u03af\u03b4\u03b1\u03c2<\/th>\n<th>Example Product<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Rod Side<\/td>\n<td>\u03a3\u03c6\u03c1\u03b1\u03b3\u03af\u03b4\u03b1 \u03c1\u03ac\u03b2\u03b4\u03bf\u03c5<\/td>\n<td><a href=\"https:\/\/hengoseal.com\/el\/un-hydraulic-seal-guide\/\" target=\"_blank\">\u03a5\u03b4\u03c1\u03b1\u03c5\u03bb\u03b9\u03ba\u03ae \u03c3\u03c6\u03c1\u03b1\u03b3\u03af\u03b4\u03b1 \u03c4\u03bf\u03c5 \u039f\u0397\u0395<\/a><\/td>\n<\/tr>\n<tr>\n<td>Rod Side<\/td>\n<td>Buffer Seal<\/td>\n<td><a href=\"https:\/\/hengoseal.com\/el\/kdas-seal-guide\/\" target=\"_blank\">\u03a3\u03c5\u03bc\u03c0\u03b1\u03b3\u03ae\u03c2 \u03c3\u03c6\u03c1\u03b1\u03b3\u03af\u03b4\u03b1 KDAS<\/a> or UHS<\/td>\n<\/tr>\n<tr>\n<td>Rod Side<\/td>\n<td>\u03a3\u03c6\u03c1\u03b1\u03b3\u03af\u03b4\u03b1 \u03c5\u03b1\u03bb\u03bf\u03ba\u03b1\u03b8\u03b1\u03c1\u03b9\u03c3\u03c4\u03ae\u03c1\u03b1<\/td>\n<td>Custom Dust Seal<\/td>\n<\/tr>\n<tr>\n<td>Piston Side<\/td>\n<td>\u03a3\u03c4\u03b5\u03b3\u03b1\u03bd\u03bf\u03c0\u03bf\u03b9\u03b7\u03c4\u03b9\u03ba\u03cc \u03ad\u03bc\u03b2\u03bf\u03bb\u03bf<\/td>\n<td><a href=\"https:\/\/hengoseal.com\/el\/idu-vs-odu-seals-guide\/\" target=\"_blank\">\u03a3\u03c6\u03c1\u03b1\u03b3\u03af\u03b4\u03b1 IDU\/ODU<\/a><\/td>\n<\/tr>\n<tr>\n<td>Guide<\/td>\n<td>Wear Ring<\/td>\n<td>FA or PTFE Guide Band<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><img decoding=\"async\" src=\"http:\/\/hengoseal.com\/wp-content\/uploads\/2025\/05\/STD-Rotary-Glyd-Ring.png\" alt=\"placeholder_image\" \/><\/p>\n<p>Depending on the application, you can swap KDAS for <a href=\"https:\/\/hengoseal.com\/el\/v-type-hydraulic-seals-guide\/\" target=\"_blank\">V-type seals<\/a> or use <a href=\"https:\/\/hengoseal.com\/el\/uhs-vs-ush-seals-guide\/\" target=\"_blank\">USH buffer seals<\/a> for higher extrusion resistance.<\/p>\n<h2>How do you choose seals based on pressure and stroke?<\/h2>\n<table>\n<thead>\n<tr>\n<th>\u039a\u03b1\u03c4\u03ac\u03c3\u03c4\u03b1\u03c3\u03b7<\/th>\n<th>Recommended Seals<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Pressure \u2264 25 MPa<\/td>\n<td>UN + IDU + UHS<\/td>\n<\/tr>\n<tr>\n<td>Pressure 25\u201340 MPa<\/td>\n<td>UN + KDAS + ODU<\/td>\n<\/tr>\n<tr>\n<td>Pressure \u2265 40 MPa<\/td>\n<td>V-type seal + USH buffer<\/td>\n<\/tr>\n<tr>\n<td>Stroke \u2264 100mm<\/td>\n<td>IDU + KDAS<\/td>\n<\/tr>\n<tr>\n<td>Stroke \u2265 300mm<\/td>\n<td>ODU + USH + reinforced wiper<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><img decoding=\"async\" src=\"http:\/\/hengoseal.com\/wp-content\/uploads\/2025\/05\/J-Hydraulic-Seals.jpg\" alt=\"placeholder_image\" \/><\/p>\n<p>If your application involves sudden pressure spikes or long-stroke movement, you\u2019ll need additional buffer or guide elements to prevent seal blowout and misalignment.<\/p>\n<p>Need help measuring your groove? Visit our guide on <a href=\"https:\/\/hengoseal.com\/el\/how-to-measure-hydraulic-seals\/\" target=\"_blank\">how to measure hydraulic seals<\/a> accurately.<\/p>\n<h2>What materials should you use in a seal stack?<\/h2>\n<p>Choosing the right material ensures your seal stack resists wear, heat, and chemical damage.<\/p>\n<table>\n<thead>\n<tr>\n<th>\u03a5\u03bb\u03b9\u03ba\u03cc<\/th>\n<th>\u03a0\u03b5\u03c1\u03af\u03c0\u03c4\u03c9\u03c3\u03b7 \u03c7\u03c1\u03ae\u03c3\u03b7\u03c2<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>NBR<\/td>\n<td>Mineral oil systems, -30~100\u00b0C<\/td>\n<\/tr>\n<tr>\n<td>FKM<\/td>\n<td>High-temp or fuel systems, up to 200\u00b0C<\/td>\n<\/tr>\n<tr>\n<td>PU<\/td>\n<td>Abrasion-resistant, long-stroke systems<\/td>\n<\/tr>\n<tr>\n<td>PTFE<\/td>\n<td>Chemical resistance, low friction<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>You can combine materials\u2014such as a PTFE piston seal with a PU buffer and FKM rod seal\u2014for optimal performance in multi-fluid systems.<\/p>\n<h2>What are the most common sealing failures\u2014and how to avoid them?<\/h2>\n<ol>\n<li><strong>Leakage<\/strong> \u2013 Caused by undersized seals or incorrect groove.<\/li>\n<li><strong>Extrusion<\/strong> \u2013 Happens under high pressure without buffer rings.<\/li>\n<li><strong>Wear<\/strong> \u2013 From side loading or dry friction.<\/li>\n<li><strong>\u039c\u03cc\u03bb\u03c5\u03bd\u03c3\u03b7<\/strong> \u2013 When no wiper seal is used.<\/li>\n<\/ol>\n<p>To avoid these, follow our <a href=\"https:\/\/hengoseal.com\/el\/seal-failure-causes-prevention-guide\/\" target=\"_blank\">seal failure prevention guide<\/a> and always use a complete stack.<\/p>\n<h2>\u03a3\u03cd\u03bd\u03b1\u03c8\u03b7<\/h2>\n<p>A well-designed hydraulic seal stack is the foundation of a leak-free, high-performance cylinder. Pair the right seal types, materials, and dimensions\u2014and your system will thank you.<\/p>\n<h2>Get your custom seal stack designed today<\/h2>\n<p>\ud83d\udce9 mail:info@hengoseal.com<br \/>\n\ud83d\udcde WhatsApp\uff1a+86 17622979498<\/p>\n<h2>Related topic<\/h2>\n<ul>\n<li><a href=\"https:\/\/hengoseal.com\/el\/kdas-seal-guide\/\" target=\"_blank\">KDAS Hydraulic Seals: Which Buffer Seal Is Best?<\/a><\/li>\n<li><a href=\"https:\/\/hengoseal.com\/el\/un-hydraulic-seal-guide\/\" target=\"_blank\">UN Hydraulic Seal Guide<\/a><\/li>\n<li><a href=\"https:\/\/hengoseal.com\/el\/idu-vs-odu-seals-guide\/\" target=\"_blank\">IDU vs ODU Piston Seals Comparison<\/a><\/li>\n<li><a href=\"https:\/\/hengoseal.com\/el\/v-type-hydraulic-seals-guide\/\" target=\"_blank\">V-Type Seals for Extreme Pressure<\/a><\/li>\n<li><a href=\"https:\/\/hengoseal.com\/el\/uhs-vs-ush-seals-guide\/\" target=\"_blank\">UHS vs USH Seal Comparison<\/a><\/li>\n<\/ul>\n<style>\n.faq-question {\ncursor: pointer;\nfont-weight: bold;\npadding: 10px;\nbackground-color: #f1f1f1;\nborder: 1px solid #ddd;\nmargin-bottom: 5px;\ncolor: #0073aa;\n}\n.faq-answer {\ndisplay: none;\npadding: 10px;\nborder-left: 3px solid #0073aa;\nbackground-color: #f9f9f9;\nmargin-bottom: 10px;\n}\n<\/style>\n<p><script>\ndocument.addEventListener('DOMContentLoaded', function() {\nconst questions = document.querySelectorAll('.faq-question');\nquestions.forEach(question => {\nquestion.addEventListener('click', function() {\nconst answer = this.nextElementSibling;\nanswer.style.display = answer.style.display === 'block' ? 'none' : 'block';\n});\n});\n});\n<\/script><br \/>\n<!-- JSON-LD FAQ Schema --><br \/>\n<script type=\"application\/ld+json\">\n{\n\"@context\": \"https:\/\/schema.org\",\n\"@type\": \"FAQPage\",\n\"mainEntity\": [\n{\n\"@type\": \"Question\",\n\"name\": \"What&rsquo;s the minimum number of seals in a hydraulic stack?\",\n\"acceptedAnswer\": {\n\"@type\": \"Answer\",\n\"text\": \"At least 3: rod, piston, and wiper.\"\n}\n},\n{\n\"@type\": \"Question\",\n\"name\": \"Can I mix different materials in one seal stack?\",\n\"acceptedAnswer\": {\n\"@type\": \"Answer\",\n\"text\": \"Yes&mdash;mixing PU, FKM, and PTFE improves versatility.\"\n}\n},\n{\n\"@type\": \"Question\",\n\"name\": \"Should buffer seals always be included?\",\n\"acceptedAnswer\": {\n\"@type\": \"Answer\",\n\"text\": \"In high-pressure or shock-load systems&mdash;yes.\"\n}\n},\n{\n\"@type\": \"Question\",\n\"name\": \"How do I know my stack has enough extrusion resistance?\",\n\"acceptedAnswer\": {\n\"@type\": \"Answer\",\n\"text\": \"Use backup rings and high-durometer materials like PTFE.\"\n}\n},\n{\n\"@type\": \"Question\",\n\"name\": \"Do OEM cylinders follow standard groove sizes?\",\n\"acceptedAnswer\": {\n\"@type\": \"Answer\",\n\"text\": \"Often yes, but we recommend measuring or requesting drawings.\"\n}\n},\n{\n\"@type\": \"Question\",\n\"name\": \"Can I buy full seal stack kits from Hengoseal?\",\n\"acceptedAnswer\": {\n\"@type\": \"Answer\",\n\"text\": \"Yes, we offer size-based or custom kits for all applications.\"\n}\n},\n{\n\"@type\": \"Question\",\n\"name\": \"What&rsquo;s the best stack for excavators?\",\n\"acceptedAnswer\": {\n\"@type\": \"Answer\",\n\"text\": \"V-pack buffer + PTFE piston + NBR rod + dust wiper.\"\n}\n},\n{\n\"@type\": \"Question\",\n\"name\": \"Can I reuse old seals during maintenance?\",\n\"acceptedAnswer\": {\n\"@type\": \"Answer\",\n\"text\": \"No. Always replace seals to prevent premature failure.\"\n}\n}\n]\n}\n<\/script><\/p>\n<h2>\u039f\u03b9 \u03ac\u03bd\u03b8\u03c1\u03c9\u03c0\u03bf\u03b9 \u03c1\u03c9\u03c4\u03bf\u03cd\u03bd \u03b5\u03c0\u03af\u03c3\u03b7\u03c2<\/h2>\n<div class=\"faq-container\">\n<div class=\"faq-question\">1. What\u2019s the minimum number of seals in a hydraulic stack?<\/div>\n<div class=\"faq-answer\">At least 3: rod, piston, and wiper.<\/div>\n<\/div>\n<div class=\"faq-container\">\n<div class=\"faq-question\">2. Can I mix different materials in one seal stack?<\/div>\n<div class=\"faq-answer\">Yes\u2014mixing PU, FKM, and PTFE improves versatility.<\/div>\n<\/div>\n<div class=\"faq-container\">\n<div class=\"faq-question\">3. Should buffer seals always be included?<\/div>\n<div class=\"faq-answer\">In high-pressure or shock-load systems\u2014yes.<\/div>\n<\/div>\n<div class=\"faq-container\">\n<div class=\"faq-question\">4. How do I know my stack has enough extrusion resistance?<\/div>\n<div class=\"faq-answer\">Use backup rings and high-durometer materials like PTFE.<\/div>\n<\/div>\n<div class=\"faq-container\">\n<div class=\"faq-question\">5. Do OEM cylinders follow standard groove sizes?<\/div>\n<div class=\"faq-answer\">Often yes, but we recommend measuring or requesting drawings.<\/div>\n<\/div>\n<div class=\"faq-container\">\n<div class=\"faq-question\">6. Can I buy full seal stack kits from Hengoseal?<\/div>\n<div class=\"faq-answer\">Yes, we offer size-based or custom kits for all applications.<\/div>\n<\/div>\n<div class=\"faq-container\">\n<div class=\"faq-question\">7. What\u2019s the best stack for excavators?<\/div>\n<div class=\"faq-answer\">V-pack buffer + PTFE piston + NBR rod + dust wiper.<\/div>\n<\/div>\n<div class=\"faq-container\">\n<div class=\"faq-question\">8. Can I reuse old seals during maintenance?<\/div>\n<div class=\"faq-answer\">No. Always replace seals to prevent premature failure.<\/div>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>Sealing just one part of your hydraulic cylinder isn\u2019t enough. To prevent leakage, absorb shocks, and reduce downtime\u2014you need a [&hellip;]<\/p>","protected":false},"author":1,"featured_media":1260,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[38],"tags":[],"class_list":["post-1258","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-hydraulic-seals"],"_links":{"self":[{"href":"https:\/\/hengoseal.com\/el\/wp-json\/wp\/v2\/posts\/1258","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hengoseal.com\/el\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hengoseal.com\/el\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hengoseal.com\/el\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/hengoseal.com\/el\/wp-json\/wp\/v2\/comments?post=1258"}],"version-history":[{"count":0,"href":"https:\/\/hengoseal.com\/el\/wp-json\/wp\/v2\/posts\/1258\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/hengoseal.com\/el\/wp-json\/wp\/v2\/media\/1260"}],"wp:attachment":[{"href":"https:\/\/hengoseal.com\/el\/wp-json\/wp\/v2\/media?parent=1258"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hengoseal.com\/el\/wp-json\/wp\/v2\/categories?post=1258"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hengoseal.com\/el\/wp-json\/wp\/v2\/tags?post=1258"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}