{"id":2717,"date":"2026-08-17T11:20:32","date_gmt":"2026-08-17T16:20:32","guid":{"rendered":"http:\/\/blog.misumiusa.com\/?p=2717"},"modified":"2026-08-18T11:30:12","modified_gmt":"2026-08-18T16:30:12","slug":"under-pressure-pneumatic-circuits","status":"publish","type":"post","link":"https:\/\/blog.misumiusa.com\/under-pressure-pneumatic-circuits\/","title":{"rendered":"How Pneumatic Circuits Work: FRL Units, Diagrams, &amp; More"},"content":{"rendered":"\n<!--\n================================================================\nMISUMI MECH LAB BLOG \u2014 CMS-READY POST\n================================================================\nTitle tag: How Pneumatic Circuits Work: FRL Units, Diagrams, & More\nMeta description: See how a pneumatic circuit moves air from compressor to actuator, why FRL units and ISO 8573-1 air quality matter, and how to read circuit diagram symbols.\nSlug: \/under-pressure-pneumatic-circuits\nPrimary keyword: pneumatic circuit\nSecondary keywords: compressed air quality, ISO 8573-1, FRL unit, pneumatic symbols\n\n================================================================\n-->\n\n<style>\n  .intro {\n    border-left: 4px solid #FFD700;\n    padding: 12px 20px;\n    margin: 0 0 32px 0;\n    font-size: 1.1rem;\n    line-height: 1.6;\n  }\n  .toc-card {\n    background: #f5f5f5;\n    border-radius: 8px;\n    padding: 20px 24px;\n    margin: 0 0 40px 0;\n  }\n  .toc-card h2 {\n    margin-top: 0;\n    font-size: 1rem;\n    text-transform: uppercase;\n    letter-spacing: 0.04em;\n    color: #1a1a18;\n    border-bottom: none !important;\n    display: block !important;\n  }\n  .toc-card ol {\n    margin: 12px 0 0 0;\n    padding-left: 20px;\n  }\n  .toc-card a {\n    text-decoration: none;\n    color: #1a1a18;\n  }\n  .toc-card a:hover {\n    text-decoration: underline;\n  }\n  article h2 {\n    display: inline-block;\n    border-bottom: 2px solid #FFD700;\n    padding-bottom: 4px;\n    margin-top: 40px;\n    margin-bottom: 16px;\n  }\n  .cta-button {\n    display: inline-block;\n    background-color: #FFD700;\n    color: #1a1a18;\n    font-weight: 700;\n    text-decoration: none;\n    padding: 12px 28px;\n    border-radius: 4px;\n    border: 2px solid #FFD700;\n    margin: 16px 0;\n  }\n  .cta-button:hover {\n    background-color: #e6c200;\n    border-color: #e6c200;\n  }\n  .cta-button--outline {\n    background-color: transparent;\n    color: #1a1a18;\n    border: 2px solid #FFD700;\n  }\n  .cta-button--outline:hover {\n    background-color: #FFD700;\n  }\n  .cta-wrap {\n    text-align: center;\n    margin: 32px 0;\n  }\n  .related-resources {\n    margin-top: 56px;\n    padding-top: 24px;\n    border-top: 1px solid #e0e0e0;\n  }\n  .related-resources h2 {\n    display: block;\n    border-bottom: none;\n  }\n  .related-resources ul {\n    list-style: none;\n    padding-left: 0;\n  }\n  .related-resources li {\n    padding: 8px 0;\n    border-bottom: 1px solid #f0f0f0;\n  }\n  .related-resources a {\n    color: #1a1a18;\n    text-decoration: none;\n    font-weight: 600;\n  }\n  .related-resources a:hover {\n    text-decoration: underline;\n  }\n<\/style>\n\n<article>\n\n<p class=\"intro\">\nDo you hear that air? The click, the swoosh, the tsks, and the wisps? All that comes from the air source on the manufacturing floor\u2014it&#8217;s compressed air doing work through a pneumatic circuit. Before that air ever reaches an actuator, though, it has to be filtered, regulated, and sometimes lubricated by an <a href=\"https:\/\/us.misumi-ec.com\/vona2\/mech\/M1900000000\/M1904000000\/M1904040000\/\">FRL unit<\/a>\u2014and getting that step wrong is one of the most common causes of premature failure in <a href=\"https:\/\/us.misumi-ec.com\/vona2\/mech\/M1900000000\/M1901000000\/\">pneumatic cylinders<\/a> and valves. Here&#8217;s how a basic circuit is built, what &#8220;clean air&#8221; actually means, and how to read the symbols on a circuit diagram.\n<\/p>\n\n<nav class=\"toc-card\" aria-label=\"Table of contents\">\n  <h2>In this article<\/h2>\n  <ol>\n    <li><a href=\"#why-clean-air\">Why compressed air needs to be cleaned before use<\/a><\/li>\n    <li><a href=\"#four-sections\">The four sections of factory air plumbing<\/a><\/li>\n    <li><a href=\"#air-quality-classes\">How air quality is actually classified<\/a><\/li>\n    <li><a href=\"#circuit-anatomy\">A typical pneumatic circuit, section by section<\/a><\/li>\n    <li><a href=\"#reading-symbols\">Reading pneumatic circuit symbols<\/a><\/li>\n    <li><a href=\"#why-pneumatics\">Why pneumatics are still the go-to choice<\/a><\/li>\n    <li><a href=\"#faq\">FAQ<\/a><\/li>\n  <\/ol>\n<\/nav>\n\n<h2 id=\"why-clean-air\">Why compressed air needs to be cleaned before it&#8217;s used<\/h2>\n<p>\nMost industrial air compressors are oil-lubricated, so the air they produce carries oil residue, water vapor, and machine dust, none of which belong inside a precision valve or cylinder. On top of that, the compressor is often far from the actuator it&#8217;s feeding, and the pipework in between is frequently shared with other machines. Every branch and every piece of shared plumbing is a chance for air quality to change before it reaches the point of use.\n<\/p>\n<p>\nAs pneumatic components have gotten smaller and more precise, driven by demand for miniaturized, lower-cost equipment, they&#8217;ve also gotten less tolerant of contamination. A speck of dust or a film of oil that an older cylinder would shrug off can cause a modern micro-valve to stick or fail. That&#8217;s exactly why the classification system below still matters, and arguably matters more than ever.\n<\/p>\n\n<h2 id=\"four-sections\">The four sections of factory air plumbing<\/h2>\n<p>Compressed air travels through four distinct zones on its way from the compressor room to the actuator:<\/p>\n<ol>\n  <li><strong>Air Source Line<\/strong>: from the compressor to the air tank\/receiver<\/li>\n  <li><strong>Main Line<\/strong>: the primary distribution header running through the facility<\/li>\n  <li><strong>Sub Line<\/strong>: branches off the main line to a work area or cell<\/li>\n  <li><strong>Terminal Line<\/strong>: the final run into an individual machine or actuator<\/li>\n<\/ol>\n<p>\nEach section can have its own filtration and moisture-management needs, which is why clean air systems are typically designed section by section rather than with a single filter at the compressor. Norgren&#8217;s air prep specialists cover practical maintenance tips for keeping each of these sections clean in <a href=\"https:\/\/us.misumi-ec.com\/blog\/achieving-optimal-air-prep-performance-with-norgren\/\">Achieving Optimal Air Prep Performance<\/a>.\n<\/p>\n\n<div class=\"cta-wrap\">\n  <a class=\"cta-button\" href=\"https:\/\/us.misumi-ec.com\/vona2\/mech\/M1900000000\/M1904000000\/M1904040000\/\">Shop FRL Units on MISUMI<\/a>\n<\/div>\n\n<h2 id=\"air-quality-classes\">How air quality is actually classified<\/h2>\n<p>Air quality requirements are set by what the air will be used for, not by a single universal standard. Typical classification tiers used across industry include:<\/p>\n<ul>\n  <li>General Industrial Air<\/li>\n  <li>Precision Industrial Air<\/li>\n  <li>Clean Air<\/li>\n  <li>Precision Clean Air<\/li>\n  <li>Ultra Precision Clean Air<\/li>\n  <li>Medical Clean Air<\/li>\n<\/ul><\/article>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a href=\"https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/Air-Quality-Classification-Chart-1.png\"><img loading=\"lazy\" decoding=\"async\" width=\"1137\" height=\"372\" src=\"https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/Air-Quality-Classification-Chart-1.png\" alt=\"\" class=\"wp-image-7891\" srcset=\"https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/Air-Quality-Classification-Chart-1.png 1137w, https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/Air-Quality-Classification-Chart-1-150x49.png 150w, https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/Air-Quality-Classification-Chart-1-300x98.png 300w, https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/Air-Quality-Classification-Chart-1-768x251.png 768w, https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/Air-Quality-Classification-Chart-1-1024x335.png 1024w\" sizes=\"auto, (max-width: 1137px) 100vw, 1137px\" \/><\/a><figcaption class=\"wp-element-caption\">Air Quality Classification Chart<\/figcaption><\/figure>\n<\/div>\n\n\n<p>\nThese tiers are evaluated against a few core parameters: the type and concentration of contaminants present, water and oil content, the size and removal rate of solid particles, and odor.\n<\/p>\n<p>\nThe internationally recognized reference for this is <strong>ISO 8573-1<\/strong>, which sorts air purity into three contaminant groups\u2014solid particles, water, and oil\u2014with each group broken into numbered classes where lower numbers mean cleaner air. First published in 1991 and revised in 2010, the current 2010 edition is still what filter and dryer manufacturers design and certify against today. A key term is <strong>dew point<\/strong> (also known as <strong>condensation point<\/strong>): the temperature at which compressed air becomes saturated and water vapor starts condensing into liquid. Air dryness is evaluated with this index.\n<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Example of a Clean Air System<\/strong><br>Various filters shown below are placed at the four classified air supply lines, and air quality corresponding to each mechanical component is generated.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a href=\"https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/CleanAirSystem.jpg\"><img loading=\"lazy\" decoding=\"async\" width=\"527\" height=\"290\" src=\"https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/CleanAirSystem.jpg\" alt=\"\" class=\"wp-image-2728\" srcset=\"https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/CleanAirSystem.jpg 527w, https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/CleanAirSystem-150x83.jpg 150w, https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/CleanAirSystem-300x165.jpg 300w\" sizes=\"auto, (max-width: 527px) 100vw, 527px\" \/><\/a><figcaption class=\"wp-element-caption\">Clean Air System Example<\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">Pneumatic circuits and control technique basics are explained based on a scenario of the factory, lab, or manufacturing environment. There are a variety of components placed downstream to the air system such as air control devices including directional valves and velocity control valves, as well as pneumatic actuators (air cylinders, etc.).<\/p>\n\n\n\n<h2 id=\"circuit-anatomy\">A typical pneumatic circuit, section by section<\/h2>\n<p>A typical pneumatic circuit is shown in [Fig. 1].<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a href=\"https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/PneumaticCircuit.jpg\"><img loading=\"lazy\" decoding=\"async\" width=\"527\" height=\"260\" src=\"https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/PneumaticCircuit.jpg\" alt=\"\" class=\"wp-image-2726\" srcset=\"https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/PneumaticCircuit.jpg 527w, https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/PneumaticCircuit-150x74.jpg 150w, https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/PneumaticCircuit-300x148.jpg 300w\" sizes=\"auto, (max-width: 527px) 100vw, 527px\" \/><\/a><figcaption class=\"wp-element-caption\">Typical Pneumatic System<\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">The compressed air generation devices are located upstream to the Air Quality Control section, and the flow control devices and actuators are placed downstream of the Air Quality Control section.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The air pressure generally used is 7kgf\/cm2 or less. The compressed air is cleaned of oil, water, and stored in the air tank, then further cleaned by the <a href=\"https:\/\/us.misumi-ec.com\/vona2\/maker\/PARKER\/mech\/M1900000000\/M1904000000\/M1904040000\/\" target=\"_blank\" rel=\"noopener noreferrer\">FRL<\/a> (<a href=\"https:\/\/us.misumi-ec.com\/vona2\/maker\/PARKER\/mech\/M1900000000\/M1904000000\/M1904010000\/\" target=\"_blank\" rel=\"noopener noreferrer\">filter<\/a>, <a href=\"https:\/\/us.misumi-ec.com\/vona2\/maker\/PARKER\/mech\/M1900000000\/M1904000000\/M1904030000\/\" target=\"_blank\" rel=\"noopener noreferrer\">regulator<\/a>, and <a href=\"https:\/\/us.misumi-ec.com\/vona2\/maker\/PARKER\/mech\/M1900000000\/M1904000000\/M1904020000\/\" target=\"_blank\" rel=\"noopener noreferrer\">lubricator<\/a>) unit, and supplied to the <a href=\"https:\/\/us.misumi-ec.com\/vona2\/mech\/M1900000000\/M1901000000\/M1901010000\/\">air cylinder<\/a> through a regulator (pressure adjustment valve).<\/p>\n\n\n\n<p>The compressor-to-air-quality-control stage behaves like a municipal water system, and the FRL\/valve stage is your faucet\u2014pressure exists upstream, but you don&#8217;t get controlled, usable flow until it passes through the fixture designed to regulate it. If you&#8217;re weighing pneumatic actuation against an electric alternative for a given motion, <a href=\"https:\/\/blog.misumiusa.com\/choosing-the-right-linear-actuator\/\">Choosing the Right Linear Actuator<\/a> walks through that trade-off in more depth.\n<\/p>\n\n<h2 id=\"reading-symbols\">Reading pneumatic circuit symbols<\/h2>\n<p>\nOne of the most practical skills in pneumatics is reading a circuit diagram at a glance. Standardized graphical symbols represent compressors, tanks, FRL units, directional control valves, and actuators, and a handful of small icons (arrows for flow direction, springs for valve return, triangles for exhaust ports, etc.) tell you how the system behaves under different conditions. Our companion post on <a href=\"https:\/\/us.misumi-ec.com\/blog\/directional-control-solenoid-valves\/\">Directional Control Solenoid Valves<\/a> breaks down how those valve symbols map to real port and spool configurations. Once you can move between a physical system like the one above and its symbolic diagram, you can troubleshoot or specify equipment far faster than working from a written description alone.\n<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The system in the [Fig. 1] is described a compressed air circuit diagram using symbols. [Fig. 2] below is a graphical symbol representation of the [Fig. 1].<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a href=\"https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/PneumaticSymbols.jpg\"><img loading=\"lazy\" decoding=\"async\" width=\"527\" height=\"180\" src=\"https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/PneumaticSymbols.jpg\" alt=\"\" class=\"wp-image-2727\" srcset=\"https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/PneumaticSymbols.jpg 527w, https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/PneumaticSymbols-150x51.jpg 150w, https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/PneumaticSymbols-300x102.jpg 300w\" sizes=\"auto, (max-width: 527px) 100vw, 527px\" \/><\/a><figcaption class=\"wp-element-caption\">Pneumatic Symbol Representation<\/figcaption><\/figure>\n<\/div>\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a href=\"https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/Common-Valve-and-Actuator-Symbols.jpg\"><img loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"774\" src=\"https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/Common-Valve-and-Actuator-Symbols.jpg\" alt=\"\" class=\"wp-image-2729\" srcset=\"https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/Common-Valve-and-Actuator-Symbols.jpg 600w, https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/Common-Valve-and-Actuator-Symbols-116x150.jpg 116w, https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/Common-Valve-and-Actuator-Symbols-233x300.jpg 233w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/a><figcaption class=\"wp-element-caption\">Pneumatic Symbols of Valves and Actuators from Automation Direct<\/figcaption><\/figure>\n<\/div>\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a href=\"https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/other-pneumatic-symbols.jpg\"><img loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"580\" src=\"https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/other-pneumatic-symbols.jpg\" alt=\"\" class=\"wp-image-2730\" srcset=\"https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/other-pneumatic-symbols.jpg 600w, https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/other-pneumatic-symbols-150x145.jpg 150w, https:\/\/blog.misumiusa.com\/wp-content\/uploads\/2017\/10\/other-pneumatic-symbols-300x290.jpg 300w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/a><figcaption class=\"wp-element-caption\">Pneumatic Symbols from Automation Direct<\/figcaption><\/figure>\n<\/div>\n\n\n<h2 id=\"why-pneumatics\">Why pneumatics are still the go-to choice<\/h2>\n<p>Despite decades of servo-electric and hydraulic alternatives, pneumatic circuits remain a default choice on factory floors for a few concrete reasons:<\/p>\n<ul>\n  <li><strong>Installation and maintenance are simple<\/strong> compared to hydraulic or fully electric systems<\/li>\n  <li><strong>Cost per actuator is low<\/strong>, especially at scale<\/li>\n  <li><strong>Power density is high<\/strong>, as pneumatic actuators deliver a lot of force for their size<\/li>\n  <li><strong>Component variety is huge<\/strong>, as compressors, filters, valves, and actuators span a wide range of sizes and specs, so circuits can be simple or elaborate depending on required force and speed<\/li>\n<\/ul>\n<p>\nFor motion profiles where pneumatics aren&#8217;t the best fit\u2014long strokes, variable speed control, or precise positioning\u2014<a href=\"https:\/\/blog.misumiusa.com\/belt-driven-actuators-loads-and-speeds\">Belt Driven Actuators: Loads &amp; Speeds<\/a> and <a href=\"https:\/\/blog.misumiusa.com\/rotary-to-linear-motion\/\">Rotary to Linear Motion<\/a> cover common electric-actuator alternatives.\n<\/p>\n\n<h2 id=\"faq\">Pneumatic circuits FAQs<\/h2>\n<p><strong>What&#8217;s the difference between a main line, sub line, and terminal line?<\/strong><br>\nThe main line is the facility-wide distribution header; sub lines branch off it to serve a work area; terminal lines are the final short run into a specific machine or actuator.<\/p>\n\n<p><strong>What does an FRL unit do?<\/strong><br>\nIt <strong>F<\/strong>ilters remaining contaminants out of the air, <strong>R<\/strong>egulates the pressure to the level the actuator needs, and (optionally) <strong>L<\/strong>ubricates the air stream for components that require it.<\/p>\n\n<p><strong>What air pressure do most pneumatic systems run at?<\/strong><br>\nTypically 7 kgf\/cm\u00b2 (about 100 psi) or less for general factory automation, though the exact figure is set by the actuator manufacturer&#8217;s specification.<\/p>\n\n<p><strong>Is ISO 8573-1 still the standard to use?<\/strong><br>\nYes. The 2010 revision is the current edition and remains the reference most filter, dryer, and compressor manufacturers design and certify against.<\/p>\n\n<p><strong>Do I need &#8220;medical clean air&#8221; for a standard assembly cell?<\/strong><br>\nNo, that tier is reserved for applications where the air itself contacts a sensitive product or environment, like pharmaceutical or medical device manufacturing. Most factory automation runs on General or Precision Industrial Air.<\/p>\n\n<div class=\"cta-wrap\">\n  <a class=\"cta-button\" href=\"https:\/\/us.misumi-ec.com\/vona2\/maker\/PARKER\/\">Shop Parker Pneumatic Components on MISUMI<\/a>\n  <a class=\"cta-button cta-button--outline\" href=\"https:\/\/us.misumi-ec.com\/vona2\/mech\/M1900000000\/M1901000000\/\">Browse Air Cylinders<\/a>\n<\/div>\n\n<div class=\"related-resources\">\n  <h2>Related resources<\/h2>\n  <ul>\n    <li><a href=\"https:\/\/us.misumi-ec.com\/blog\/achieving-optimal-air-prep-performance-with-norgren\/\">Achieving Optimal Air Prep Performance with Norgren<\/a><\/li>\n    <li><a href=\"https:\/\/us.misumi-ec.com\/blog\/directional-control-solenoid-valves\/\">Directional Control Solenoid Valves: Benefits, Material Selection &amp; Applications<\/a><\/li>\n    <li><a href=\"https:\/\/blog.misumiusa.com\/choosing-the-right-linear-actuator\/\">Choosing the Right Linear Actuator<\/a><\/li>\n    <li><a href=\"https:\/\/blog.misumiusa.com\/belt-driven-actuators-loads-and-speeds\">Belt Driven Actuators: Loads &amp; Speeds<\/a><\/li>\n    <li><a href=\"https:\/\/blog.misumiusa.com\/rotary-to-linear-motion\/\">Rotary to Linear Motion<\/a><\/li>\n  <\/ul>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Do you hear that air? The click, the swoosh, the tsks, and the wisps? All that comes from the air source on the manufacturing floor\u2014it&#8217;s compressed air doing work through a pneumatic circuit. Before that air ever reaches an actuator, though, it has to be filtered, regulated, and sometimes lubricated by an FRL unit\u2014and getting that step wrong is one [&hellip;]<\/p>\n","protected":false},"author":46,"featured_media":7893,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"footnotes":""},"categories":[1136],"tags":[564,566,570,568,563,569,562,561,567,565],"class_list":["post-2717","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-mechanical-design","tag-actuators","tag-air","tag-air-quality","tag-compressor","tag-cylinders","tag-filter","tag-pneumatic-circuit","tag-pneumatics","tag-pressure","tag-valves"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 5.0.0.1 - aioseo.com -->\n\t<meta name=\"description\" content=\"Compressed air as the energy source for factory pneumatic actuators are produced by oil-lubricated air compressors.\" 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