{"id":711,"date":"2024-12-16T09:58:21","date_gmt":"2024-12-16T08:58:21","guid":{"rendered":"https:\/\/www.valfonta.com\/blog\/hydraulic-pressure-relief-valve\/"},"modified":"2026-10-15T12:12:01","modified_gmt":"2026-10-15T10:12:01","slug":"hydraulic-pressure-relief-valve","status":"publish","type":"post","link":"https:\/\/www.valfonta.com\/en\/blog\/hydraulic-pressure-relief-valve\/","title":{"rendered":"Discover the Valfonta Model S3 hydraulic pressure relief valve"},"content":{"rendered":"<div class=\"wp-block-group vf-raiz vf-pl-articulo is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-group vf-cat-wrap is-layout-flow wp-block-group-is-layout-flow\"><article class=\"wp-block-group vf-pdp vf-post is-layout-flow wp-block-group-is-layout-flow\"><nav class=\"wp-block-group vf-breadcrumbs vfa-aria-label--Breadcrumbs is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><a href=\"\/en\/\">Home<\/a><span class=\"vf-sep\">\u203a<\/span><a href=\"\/en\/blog\/\">Blog<\/a><span class=\"vf-sep\">\u203a<\/span><span aria-current=\"page\">Discover Valfonta\u2019s S3 hydraulic pressure relief valve<\/span><\/p><\/nav><header class=\"wp-block-group vf-post-head is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-pdp-eyebrow wp-block-paragraph\"><a href=\"\/en\/pressure-relief-valve\/\">Pressure relief valves<\/a><\/p><h1 class=\"wp-block-heading\">Discover Valfonta\u2019s S3 hydraulic pressure relief valve<\/h1><p class=\"vf-post-meta wp-block-paragraph\"><span>By Valfonta<\/span><span><time datetime=\"2026-04-08\">Updated April 8, 2026<\/time><\/span><span>5 min read<\/span><\/p><\/header><figure class=\"wp-block-image size-full vf-post-hero is-resized\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/valvula-alivio-presion.png\" alt=\"Discover Valfonta\u2019s S3 hydraulic pressure relief valve\" class=\"wp-image-233\" width=\"1200\" height=\"514\"\/><\/figure><div class=\"wp-block-group vf-post-grid is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-group vf-post-body is-layout-flow wp-block-group-is-layout-flow\"><aside class=\"wp-block-group vf-post-summary vfa-aria-label--In%20summary is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-t wp-block-paragraph\">In summary<\/p><p class=\"wp-block-paragraph\">Valfonta\u2019s S3 hydraulic pressure relief valve holds the upstream set pressure and opens gradually when the inlet pressure exceeds the set value. It works with steam, gases, and liquids, with a setting range from 0.5 to 20 bar, temperatures from -10 to 220 \u00b0C, and Class IV or VI leakage class. It is not a safety valve, so additional overpressure protection is required. It must be installed in horizontal piping, with a strainer at the inlet and a gradual start-up.<\/p><\/aside><details class=\"wp-block-details vf-post-toc-m is-layout-flow wp-block-details-is-layout-flow\"><summary>Article contents<\/summary><ol class=\"wp-block-list\"><li><a href=\"#esta-valvula-de-alivio-de-presion-hidraulica-nos-ayudara-a-c\">This hydraulic pressure relief valve will help us control upstream pressure<\/a><\/li><li><a href=\"#caracteristicas-de-la-valvula-de-alivio-de-presion-hidraulic\">Features of Valfonta\u2019s S3 hydraulic pressure relief valve<\/a><\/li><li><a href=\"#funcionamiento-directo-de-la-valvula-s3\">Direct operation of the S3 valve<\/a><\/li><\/ol><\/details><h2 class=\"wp-block-heading\" id=\"esta-valvula-de-alivio-de-presion-hidraulica-nos-ayudara-a-c\">This hydraulic pressure relief valve will help us control upstream pressure<\/h2><p class=\"wp-block-paragraph\">At Valfonta we offer a <strong>broad catalog of valves<\/strong> of all kinds: pressure relief valves, control valves, hydraulic pressure control valves\u2026 covering a wide range of possible applications.<\/p><p class=\"wp-block-paragraph\">In this post, we want to tell you more specifically about the<strong> S3 hydraulic pressure relief valve<\/strong>, a component that correctly holds the upstream set pressure by adjusting the set pressure. If the inlet pressure exceeds the set value, the valve opens gradually in response to that pressure rise.<\/p><h2 class=\"wp-block-heading\" id=\"caracteristicas-de-la-valvula-de-alivio-de-presion-hidraulic\"><strong>Features of Valfonta\u2019s S3 hydraulic pressure relief valve<\/strong><\/h2><p class=\"wp-block-paragraph\">Valfonta\u2019s<a href=\"\/en\/product\/pressure-relief-valve-s3\/\"><strong> S3 hydraulic pressure relief valve<\/strong><\/a> is an effective and reliable solution for regulating and maintaining safe pressures in hydraulic systems. Built from high-quality materials such as bronze, carbon steel, and stainless steel, the S3 valve can <strong>withstand a variety of operating conditions<\/strong>, ensuring its durability and performance.<\/p><p class=\"wp-block-paragraph\">This relief valve model features <strong>a Class IV (metal-to-metal) or Class VI (PTFE+GR seat) leakage class,<\/strong> giving it the flexibility to suit different applications and sealing requirements. Its set pressure range runs from 0.5 to 20 bar, allowing it to be used in a variety of environments and applications.<\/p><figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" src=\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/valvula-de-alivio-de-presion-hidraulica-300x300-1.png\" alt=\"hydraulic pressure relief valve\" class=\"wp-image-290\" width=\"300\" height=\"300\" loading=\"lazy\"\/><\/figure><p class=\"wp-block-paragraph\">The S3 valve operates efficiently at temperatures from -10 to 220\u00baC in materials 0.7043 and 1.0619, and from -30 to 220\u00baC in 1.4408. With special gaskets, it can handle temperatures up to 250\u00baC.<\/p><p class=\"wp-block-paragraph\">Meeting strict quality and safety standards, the S3 hydraulic pressure relief valve <strong>complies with ISO 9001<\/strong>, the Pressure Equipment Directive 2014\/68\/EU, and the<strong> ATEX Directive 2014\/34\/EU.<\/strong> These certifications not only <strong>ensure its quality and reliability<\/strong>, but also guarantee its suitability for use in regulated and demanding environments.<\/p><h2 class=\"wp-block-heading\" id=\"funcionamiento-directo-de-la-valvula-s3\"><strong>Direct operation of the S3 valve<\/strong><\/h2><p class=\"wp-block-paragraph\">The <strong>operation of the S3 valve is direct and efficient<\/strong>. Its main purpose is to hold the preset upstream pressure by automatically adjusting the set pressure. If the inlet pressure exceeds the set value, the valve opens gradually to relieve the excess pressure, thus preventing possible damage to the system.<\/p><p class=\"wp-block-paragraph\">It is important to stress that the S3 valve is not a safety valve. Therefore, <strong>additional overpressure protection must be installed in the system.<\/strong> This valve is versatile and suitable for applications with steam, gases, and liquids, which <strong>broadens its range<\/strong> of use across different industries and processes.<\/p><p class=\"wp-block-paragraph\">To ensure optimum operation, it is essential to protect the S3 valve <strong>against adverse influences such as dirt, moisture, and extreme temperatures<\/strong>. During installation, the inside of the valve must be carefully cleaned. In addition, given its complexity and the applicable regulations, installation must be carried out exclusively by specialized personnel.<\/p><figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" src=\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/donde-se-coloca-la-valvula-reductora-de-presion-1.webp\" alt=\"where to install a pressure reducing valve\" class=\"wp-image-258\" width=\"800\" height=\"581\" loading=\"lazy\"\/><\/figure><p class=\"wp-block-paragraph\">Over time, it is normal for some <strong>pressure deviations to appear in the S3 valve due to continuous use,<\/strong> such as pressures that exceed the set point, pressure drops below the set point, control oscillations, inlet pressure fluctuations, and noise. However, these deviations are generally minor and can be corrected quickly depending on the type of problem.<\/p><p class=\"wp-block-paragraph\">In short, Valfonta\u2019s S3 hydraulic pressure relief valve is an essential component for pressure management in hydraulic systems, offering reliability, versatility, and compliance with safety and quality standards. Its <strong>advanced design and high-quality materials<\/strong> ensure exceptional performance and a long service life in a wide range of industrial applications.<\/p><h3 class=\"wp-block-heading\" id=\"recomendaciones-para-la-instalacion-de-la-valvula-de-alivio-\">Installation Recommendations for the Hydraulic Pressure Relief Valve<\/h3><p class=\"wp-block-paragraph\">Proper installation of the valve is key to ensuring optimum performance and extending its service life. Below are the best practices for correctly installing the S3 model:<\/p><div class=\"wp-block-group vf-t-ul is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-group vf-t-li is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><i><\/i><\/p><p class=\"wp-block-paragraph\"><strong>Clean the pipe beforehand:<\/strong><br> Before installing the valve, it is essential to thoroughly clean the system to remove debris, impurities, or particles that could clog or damage the valve.<\/p><\/div><div class=\"wp-block-group vf-t-li is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><i><\/i><\/p><p class=\"wp-block-paragraph\"><strong>Horizontal installation:<\/strong><br> The valve should preferably be installed in horizontal piping to ensure efficient operation. The flow direction must match the arrow marked on the valve body.<\/p><\/div><div class=\"wp-block-group vf-t-li is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><i><\/i><\/p><p class=\"wp-block-paragraph\"><strong>Use protective strainers:<\/strong><br> To prevent possible damage from particles, installing a strainer at the valve inlet is recommended. This ensures that the fluid arrives clean and free of obstructions.<\/p><\/div><div class=\"wp-block-group vf-t-li is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><i><\/i><\/p><p class=\"wp-block-paragraph\"><strong>Supports close to the valve:<\/strong><br> System supports should be placed as close as possible to the valve, but without being fastened directly to the body or the actuator. This helps avoid unnecessary stress or vibration.<\/p><\/div><div class=\"wp-block-group vf-t-li is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><i><\/i><\/p><p class=\"wp-block-paragraph\"><strong>Gradual start-up:<\/strong><br> During start-up, it is important to open the shutoff valves slowly to avoid water hammer that could damage the valve and the system. Once in operation, the desired pressure is set with the adjusting screw.<\/p><\/div><\/div><h3 class=\"wp-block-heading\" id=\"mantenimiento-preventivo-de-la-valvula-s3\">Preventive Maintenance of the S3 Valve<\/h3><p class=\"wp-block-paragraph\">Regular maintenance of the hydraulic pressure relief valve is essential to ensure its reliability and extend its service life. Here are some key recommendations:<\/p><div class=\"wp-block-group vf-t-ul is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-group vf-t-li is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><i><\/i><\/p><p class=\"wp-block-paragraph\"><strong>Protection against external influences:<\/strong><br> The valve must be protected from adverse conditions such as dirt, moisture, and extreme temperatures that could compromise its performance.<\/p><\/div><div class=\"wp-block-group vf-t-li is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><i><\/i><\/p><p class=\"wp-block-paragraph\"><strong>Periodic inspections:<\/strong><br> Regular checks are recommended to detect possible deviations in the set pressure, leaks, or buildup of debris.<\/p><\/div><div class=\"wp-block-group vf-t-li is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><i><\/i><\/p><p class=\"wp-block-paragraph\"><strong>Internal cleaning:<\/strong><br> Over time, the buildup of particles or impurities can affect valve operation. The inside must be cleaned carefully and only by specialized personnel.<\/p><\/div><div class=\"wp-block-group vf-t-li is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><i><\/i><\/p><p class=\"wp-block-paragraph\"><strong>Pressure readjustment:<\/strong><br> In the event of deviations such as pressures that exceed or fall below the set point, it is important to correct the adjusting screw to restore the preset values.<\/p><\/div><\/div><\/div><aside class=\"wp-block-group vf-post-aside is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-group vf-post-sticky is-layout-flow wp-block-group-is-layout-flow\"><nav class=\"wp-block-group vf-post-toc vfa-aria-label--Article%20contents is-layout-flow wp-block-group-is-layout-flow\"><p class=\"wp-block-paragraph\">In this article<\/p><ol class=\"wp-block-list\"><li><a href=\"#esta-valvula-de-alivio-de-presion-hidraulica-nos-ayudara-a-c\">This hydraulic pressure relief valve will help us control upstream pressure<\/a><\/li><li><a href=\"#caracteristicas-de-la-valvula-de-alivio-de-presion-hidraulic\">Features of Valfonta\u2019s S3 hydraulic pressure relief valve<\/a><\/li><li><a href=\"#funcionamiento-directo-de-la-valvula-s3\">Direct operation of the S3 valve<\/a><\/li><\/ol><\/nav><div class=\"wp-block-group vf-post-cta is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-t wp-block-paragraph\">Do you need a pressure relief or excess pressure valve?<\/p><p class=\"wp-block-paragraph\">We help you choose the right model and size for your installation.<\/p><p class=\"vf-envolt wp-block-paragraph\"><a class=\"vf-btn vf-btn--pri\" href=\"#contactar\">Request a quote<\/a><\/p><p class=\"vf-envolt wp-block-paragraph\"><a class=\"vf-btn vf-btn--sec\" href=\"\/en\/pressure-relief-valve\/\">View pressure relief valves<\/a><\/p><p class=\"vf-tel wp-block-paragraph\">Or call <a href=\"tel:+34933720888\">933 720 888<\/a><\/p><\/div><\/div><\/aside><\/div><section id=\"valvulas\" class=\"wp-block-group is-layout-flow wp-block-group-is-layout-flow\"><h2 class=\"wp-block-heading\">Related valves<\/h2><ul class=\"vf-rel wp-block-list\"><li><a href=\"\/en\/product\/pressure-relief-valve-s3\/\"><img decoding=\"async\" src=\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/valvula-alivio-presion-s3-s4-perspectiva-400.webp\" alt=\"S3 pressure relief valve\" class=\"wp-image-10230\" width=\"300\" height=\"300\" loading=\"lazy\"><b>S3 pressure relief valve<\/b><span>From DN15 to DN150, PN40, set pressure up to 20 barg and 220 \u00b0C.<\/span><\/a><\/li><li><a href=\"\/en\/product\/pressure-excess-valve-s1\/\"><img decoding=\"async\" src=\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/ok-M1-S1-3D-700x700-1.jpg\" alt=\"S1 excess pressure valve\" class=\"wp-image-192\" width=\"300\" height=\"300\" loading=\"lazy\"><b>S1 excess pressure valve<\/b><span>From DN15 to DN150 and PN40, for steam up to 220 \u00b0C.<\/span><\/a><\/li><li><a href=\"\/en\/product\/pressure-excess-valve-s2\/\"><img decoding=\"async\" src=\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/ok-M2-PROVISIONAL-700x700-1.jpg\" alt=\"S2 excess pressure valve\" class=\"wp-image-193\" width=\"300\" height=\"300\" loading=\"lazy\"><b>S2 excess pressure valve<\/b><span>From DN15 to DN100, PN40, and set pressure from 0.02 barg.<\/span><\/a><\/li><\/ul><p class=\"vf-post-more wp-block-paragraph\"><a href=\"\/en\/pressure-relief-valve\/\">View all pressure relief valves \u2192<\/a><\/p><\/section><section id=\"articulos\" class=\"wp-block-group is-layout-flow wp-block-group-is-layout-flow\"><h2 class=\"wp-block-heading\">Related articles<\/h2><div class=\"wp-block-group vf-post-cards vf-t-ul is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-group vf-t-li is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-group vf-amb-enllac is-layout-flow wp-block-group-is-layout-flow\"><figure class=\"wp-block-image vf-img-suelta\"><img decoding=\"async\" src=\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/gas.jpg\" alt=\"\" class=\"wp-image-243\" width=\"400\" height=\"225\" loading=\"lazy\"><\/figure><div class=\"wp-block-group vf-in is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><small>Pressure relief valves<\/small><b>Valfonta pressure relief valves for fire protection<\/b><span>7 min read<\/span><\/p><\/div><p class=\"vf-enllac wp-block-paragraph\"><a class=\"vf-enllac-estirat\" href=\"\/en\/blog\/fire-protection-pressure-relief-valves\/\" aria-label=\"Pressure relief valves Valfonta pressure relief valves for fire protection 7 min read\"><\/a><\/p><\/div><\/div><div class=\"wp-block-group vf-t-li is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-group vf-amb-enllac is-layout-flow wp-block-group-is-layout-flow\"><figure class=\"wp-block-image vf-img-suelta\"><img decoding=\"async\" src=\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/valvula-alivio-presion.png\" alt=\"\" class=\"wp-image-233\" width=\"400\" height=\"225\" loading=\"lazy\"><\/figure><div class=\"wp-block-group vf-in is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><small>Pressure relief valves<\/small><b>What are the main features of a pneumatic pressure relief valve?<\/b><span>5 min read<\/span><\/p><\/div><p class=\"vf-enllac wp-block-paragraph\"><a class=\"vf-enllac-estirat\" href=\"\/en\/blog\/pneumatic-pressure-relief-valve\/\" aria-label=\"Pressure relief valves What are the main features of a pneumatic pressure relief valve? 5 min read\"><\/a><\/p><\/div><\/div><div class=\"wp-block-group vf-t-li is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-group vf-amb-enllac is-layout-flow wp-block-group-is-layout-flow\"><figure class=\"wp-block-image vf-img-suelta\"><img decoding=\"async\" src=\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/alivio-de-presionpara-agua-gases-y-vapor1.jpg\" alt=\"\" class=\"wp-image-167\" width=\"400\" height=\"225\" loading=\"lazy\"><\/figure><div class=\"wp-block-group vf-in is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><small>Pressure relief valves<\/small><b>Pressure relief valve for water, steam, and gases: definition and operation<\/b><span>10 min read<\/span><\/p><\/div><p class=\"vf-enllac wp-block-paragraph\"><a class=\"vf-enllac-estirat\" href=\"\/en\/blog\/water-pressure-relief-valve\/\" aria-label=\"Pressure relief valves Pressure relief valve for water, steam, and gases: definition and operation 10 min read\"><\/a><\/p><\/div><\/div><\/div><\/section><section id=\"contactar\" class=\"wp-block-group is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-group vf-quote is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-group is-layout-flow wp-block-group-is-layout-flow\"><h2 class=\"wp-block-heading\">Can we help with your installation?<\/h2><p class=\"wp-block-paragraph\">Tell us the fluid, the inlet and outlet pressures, the temperature, and the flow rate, and we will recommend the right valve.<\/p><p class=\"vf-pdp-contact wp-block-paragraph\">You can also call <a href=\"tel:+34933720888\">933 720 888<\/a> or email <a href=\"mailto:valfonta@valfonta.com\">valfonta@valfonta.com<\/a>.<\/p><\/div>\n<div class=\"wpcf7 no-js\" id=\"wpcf7-f535-o1\" lang=\"en-US\" dir=\"ltr\" data-wpcf7-id=\"535\">\n<div class=\"screen-reader-response\"><p role=\"status\" aria-live=\"polite\" aria-atomic=\"true\"><\/p> <ul><\/ul><\/div>\n<form action=\"\/en\/wp-json\/wp\/v2\/posts\/711#wpcf7-f535-o1\" method=\"post\" class=\"wpcf7-form init vf-form wpcf7-acceptance-as-validation\" aria-label=\"Contact form\" novalidate=\"novalidate\" data-status=\"init\" toolname=\"consulta_contacto\" tooldescription=\"Send an enquiry to Valfonta, industrial valve manufacturer; a member of the team will reply.\">\n<fieldset class=\"hidden-fields-container\"><input type=\"hidden\" name=\"_wpcf7\" value=\"535\" \/><input type=\"hidden\" name=\"_wpcf7_version\" value=\"6.2.3\" \/><input type=\"hidden\" name=\"_wpcf7_locale\" value=\"en_US\" \/><input type=\"hidden\" name=\"_wpcf7_unit_tag\" value=\"wpcf7-f535-o1\" \/><input type=\"hidden\" name=\"_wpcf7_container_post\" value=\"0\" \/><input type=\"hidden\" name=\"_wpcf7_posted_data_hash\" value=\"\" \/><input type=\"hidden\" name=\"_vf_t\" value=\"1792706062.2a7496c8d454a4ee\" \/>\n<\/fieldset>\n<label>Name *<span class=\"wpcf7-form-control-wrap\" data-name=\"nombre\"><input size=\"40\" maxlength=\"400\" class=\"wpcf7-form-control wpcf7-text wpcf7-validates-as-required\" autocomplete=\"name\" aria-required=\"true\" aria-invalid=\"false\" value=\"\" type=\"text\" name=\"nombre\" \/><\/span><\/label><label>Company<span class=\"wpcf7-form-control-wrap\" data-name=\"empresa\"><input size=\"40\" maxlength=\"400\" class=\"wpcf7-form-control wpcf7-text\" autocomplete=\"organization\" aria-invalid=\"false\" value=\"\" type=\"text\" name=\"empresa\" \/><\/span><\/label><label>Email *<span class=\"wpcf7-form-control-wrap\" data-name=\"email\"><input size=\"40\" maxlength=\"400\" class=\"wpcf7-form-control wpcf7-email wpcf7-validates-as-required wpcf7-text wpcf7-validates-as-email\" autocomplete=\"email\" aria-required=\"true\" aria-invalid=\"false\" value=\"\" type=\"email\" name=\"email\" \/><\/span><\/label><label>Phone<span class=\"wpcf7-form-control-wrap\" data-name=\"telefono\"><input size=\"40\" maxlength=\"400\" class=\"wpcf7-form-control wpcf7-tel wpcf7-text wpcf7-validates-as-tel\" autocomplete=\"tel\" aria-invalid=\"false\" value=\"\" type=\"tel\" name=\"telefono\" \/><\/span><\/label><label class=\"vf-full\">Reason for your inquiry<span class=\"wpcf7-form-control-wrap\" data-name=\"motivo\"><select class=\"wpcf7-form-control wpcf7-select\" aria-invalid=\"false\" name=\"motivo\"><option value=\"\">Select<\/option><option value=\"Request a quote\">Request a quote<\/option><option value=\"Technical advice on choosing a valve\">Technical advice on choosing a valve<\/option><option value=\"Spare parts or repair\">Spare parts or repair<\/option><option value=\"Documentation or certificates\">Documentation or certificates<\/option><option value=\"Other\">Other<\/option><\/select><\/span><\/label><label class=\"vf-full\">Message *<span class=\"wpcf7-form-control-wrap\" data-name=\"mensaje\"><textarea cols=\"40\" rows=\"5\" maxlength=\"2000\" class=\"wpcf7-form-control wpcf7-textarea wpcf7-validates-as-required\" aria-required=\"true\" aria-invalid=\"false\" placeholder=\"Tell us what you need: fluid, pressures, flow rate, model, or serial number\u2026\" name=\"mensaje\"><\/textarea><\/span><\/label><label class=\"vf-chk vf-full\"><span class=\"wpcf7-form-control-wrap\" data-name=\"privacidad\"><span class=\"wpcf7-form-control wpcf7-acceptance\"><span class=\"wpcf7-list-item\"><input type=\"checkbox\" name=\"privacidad\" value=\"1\" aria-invalid=\"false\" \/><\/span><\/span><\/span> <span>I have read and accept the <a href=\"\/en\/privacy-policy\/\">privacy policy<\/a> *<\/span><\/label><input class=\"wpcf7-form-control wpcf7-submit has-spinner vf-btn vf-btn--pri\" type=\"submit\" value=\"Send message\" \/><span class=\"vf-hp\" aria-hidden=\"true\"><label>Web <input type=\"text\" name=\"vf_web\" value=\"\" tabindex=\"-1\" autocomplete=\"off\" toolparamdescription=\"Campo de control: d\u00e9jalo vac\u00edo\"><\/label><\/span><div class=\"wpcf7-response-output\" aria-hidden=\"true\"><\/div>\n<\/form>\n<\/div>\n\n<\/div><\/section><div class=\"wp-block-group vf-pdp-bar is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><a class=\"vf-btn vf-btn--sec\" href=\"tel:+34933720888\">Call<\/a><a class=\"vf-btn vf-btn--pri\" href=\"#contactar\">Request a quote<\/a><\/p><\/div><\/article><\/div><\/div>","protected":false},"excerpt":{"rendered":"<p>The Valfonta S3 hydraulic pressure relief valve holds the set pressure upstream and opens gradually when the inlet pressure exceeds the set value.<\/p>\n","protected":false},"author":1,"featured_media":233,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_generate-full-width-content":"true","_generate-disable-headline":"true","rank_math_title":"Hydraulic pressure relief valve | Valfonta","rank_math_description":"Hydraulic pressure relief valve. Technical features of the S3 model for a long list of industrial systems and applications.","rank_math_focus_keyword":"","vf_jsonld":"[{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"Organization\",\"@id\":\"https:\/\/www.valfonta.com\/#organization\",\"name\":\"Valfonta\",\"legalName\":\"Val Fonta, S.L.\",\"taxID\":\"B59935718\",\"url\":\"https:\/\/www.valfonta.com\/en\/\",\"logo\":{\"@type\":\"ImageObject\",\"url\":\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/valfonta-logo.webp\"},\"foundingDate\":\"1962\",\"email\":\"valfonta@valfonta.com\",\"telephone\":\"+34 933 720 888\",\"address\":{\"@type\":\"PostalAddress\",\"streetAddress\":\"C\/ Bronze 26, Pol. Ind. Les Guixeres\",\"postalCode\":\"08915\",\"addressLocality\":\"Badalona\",\"addressRegion\":\"Barcelona\",\"addressCountry\":\"ES\"},\"description\":\"Design, manufacture, and sale of pressure reducing valves, pressure relief valves, and control valves.\"},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/www.valfonta.com\/#website\",\"url\":\"https:\/\/www.valfonta.com\/en\/\",\"name\":\"Valfonta\",\"publisher\":{\"@id\":\"https:\/\/www.valfonta.com\/#organization\"},\"inLanguage\":\"en\"},{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.valfonta.com\/en\/blog\/hydraulic-pressure-relief-valve\/#webpage\",\"url\":\"https:\/\/www.valfonta.com\/en\/blog\/hydraulic-pressure-relief-valve\/\",\"name\":\"Hydraulic pressure relief valve | Valfonta\",\"description\":\"Hydraulic pressure relief valve. Technical features of the S3 model for a long list of industrial systems and applications.\",\"isPartOf\":{\"@id\":\"https:\/\/www.valfonta.com\/#website\"},\"about\":{\"@id\":\"https:\/\/www.valfonta.com\/#organization\"},\"inLanguage\":\"en\",\"datePublished\":\"2024-12-16T09:58:21+02:00\",\"dateModified\":\"2026-04-08T13:38:34+02:00\",\"primaryImageOfPage\":{\"@id\":\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/valvula-alivio-presion.png\"},\"breadcrumb\":{\"@id\":\"https:\/\/www.valfonta.com\/en\/blog\/hydraulic-pressure-relief-valve\/#breadcrumb\"}},{\"@type\":\"ImageObject\",\"@id\":\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/valvula-alivio-presion.png\",\"url\":\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/valvula-alivio-presion.png\",\"caption\":\"Discover Valfonta\u2019s S3 hydraulic pressure relief valve\",\"inLanguage\":\"en\"},{\"@type\":\"ImageObject\",\"@id\":\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/valvula-alivio-presion.png\",\"url\":\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/valvula-alivio-presion.png\",\"width\":\"1000\",\"height\":\"1000\",\"caption\":\"Pressure relief valve\",\"inLanguage\":\"en\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/www.valfonta.com\/en\/blog\/hydraulic-pressure-relief-valve\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/www.valfonta.com\/en\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Blog\",\"item\":\"https:\/\/www.valfonta.com\/en\/blog\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Discover Valfonta\u2019s S3 hydraulic pressure relief valve\",\"item\":\"https:\/\/www.valfonta.com\/en\/blog\/hydraulic-pressure-relief-valve\/\"}]},{\"@type\":\"BlogPosting\",\"keywords\":\"hydraulic pressure relief valve\",\"datePublished\":\"2024-12-16T09:58:21+02:00\",\"dateModified\":\"2026-04-08T13:38:34+02:00\",\"articleSection\":\"Pressure relief valves\",\"publisher\":{\"@id\":\"https:\/\/www.valfonta.com\/#organization\"},\"@id\":\"https:\/\/www.valfonta.com\/en\/blog\/hydraulic-pressure-relief-valve\/#richSnippet\",\"isPartOf\":{\"@id\":\"https:\/\/www.valfonta.com\/en\/blog\/hydraulic-pressure-relief-valve\/#webpage\"},\"image\":{\"@id\":\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/valvula-alivio-presion.png\"},\"inLanguage\":\"en\",\"mainEntityOfPage\":{\"@id\":\"https:\/\/www.valfonta.com\/en\/blog\/hydraulic-pressure-relief-valve\/#webpage\"},\"headline\":\"Discover Valfonta\u2019s S3 hydraulic pressure relief valve\",\"name\":\"Hydraulic pressure relief valve | Valfonta\",\"description\":\"Hydraulic pressure relief valve. Technical features of the S3 model for a long list of industrial systems and applications.\",\"author\":{\"@id\":\"https:\/\/www.valfonta.com\/#organization\"},\"abstract\":\"Valfonta\u2019s S3 hydraulic pressure relief valve holds the upstream set pressure and opens gradually when the inlet pressure exceeds the set value. It works with steam, gases, and liquids, with a setting range from 0.5 to 20 bar, temperatures from -10 to 220 \u00b0C, and Class IV or VI leakage class. It is not a safety valve, so additional overpressure protection is required. It must be installed in horizontal piping, with a strainer at the inlet and a gradual start-up.\"}]}]","footnotes":"","_vg_translation_of":"488","_vg_lang":"en","_vg_wpml_state":"{\"lang\":\"en\",\"trid\":\"672\",\"src\":\"es\"}"},"categories":[37],"tags":[],"class_list":["post-711","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-relief-and-safety"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.valfonta.com\/en\/wp-json\/wp\/v2\/posts\/711","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.valfonta.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.valfonta.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.valfonta.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.valfonta.com\/en\/wp-json\/wp\/v2\/comments?post=711"}],"version-history":[{"count":3,"href":"https:\/\/www.valfonta.com\/en\/wp-json\/wp\/v2\/posts\/711\/revisions"}],"predecessor-version":[{"id":10287,"href":"https:\/\/www.valfonta.com\/en\/wp-json\/wp\/v2\/posts\/711\/revisions\/10287"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.valfonta.com\/en\/wp-json\/wp\/v2\/media\/233"}],"wp:attachment":[{"href":"https:\/\/www.valfonta.com\/en\/wp-json\/wp\/v2\/media?parent=711"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.valfonta.com\/en\/wp-json\/wp\/v2\/categories?post=711"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.valfonta.com\/en\/wp-json\/wp\/v2\/tags?post=711"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}