{"id":5508,"date":"2022-09-28T17:00:00","date_gmt":"2022-09-28T15:00:00","guid":{"rendered":"https:\/\/www.idro-elettrica.it\/esperto-risponde\/how-does-a-centrifugal-pump-work\/"},"modified":"2026-07-01T09:47:37","modified_gmt":"2026-07-01T07:47:37","slug":"how-does-a-centrifugal-pump-work","status":"publish","type":"esperto-risponde","link":"https:\/\/www.idro-elettrica.it\/en\/esperto-risponde\/how-does-a-centrifugal-pump-work\/","title":{"rendered":"How a Centrifugal Pump Works: 7 Key Points"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\"><em>&#8220;How does a centrifugal pump work<\/em>?&#8221; is one of the most common questions when it comes to moving a fluid in a system. Here you&#8217;ll find a technical yet accessible explanation: components, operating principle, performance curve, and practical criteria for selecting the most suitable pump. <\/p>\n\n<div class=\"wp-block-rank-math-toc-block\" id=\"rank-math-toc\"><h2>Table of Contents<\/h2><nav><ul><li class=\"\"><a href=\"#cosa-sono-le-pompe-centrifughe\">What Are Centrifugal Pumps?<\/a><\/li><li class=\"\"><a href=\"#i-componenti-principali-di-una-pompa-centrifuga\">The Main Components of a Centrifugal Pump<\/a><\/li><li class=\"\"><a href=\"#classificazione-e-installazione-orizzontale-verticale-e-condizioni-idrauliche\">Classification and Installation (Horizontal\/Vertical and Hydraulic Conditions)<\/a><\/li><li class=\"\"><a href=\"#come-funziona-una-pompa-centrifuga-principio-di-lavoro\">How a Centrifugal Pump Works (Principle of Operation)<\/a><\/li><li class=\"\"><a href=\"#girante-e-voluta-cosa-succede-al-fluido-dentro-la-pompa\">Impeller and volute: what happens to the fluid inside the pump<\/a><\/li><li class=\"\"><a href=\"#curva-caratteristica-e-rendimento-di-una-pompa-centrifuga\">Performance Curve and Efficiency of a Centrifugal Pump<\/a><\/li><li class=\"\"><a href=\"#come-scegliere-la-pompa-portata-prevalenza-e-perdite-dellimpianto\">How to Choose a Pump: Flow Rate, Head, and System Leaks<\/a><\/li><li class=\"\"><a href=\"#caratteristiche-del-fluido-cosa-valutare-prima-della-scelta\">Fluid Characteristics: What to Consider Before Making a Choice<\/a><\/li><li class=\"\"><a href=\"#conclusione\">Conclusion<\/a><\/li><\/ul><\/nav><\/div>\n\n<h2 id=\"cosa-sono-le-pompe-centrifughe\" class=\"wp-block-heading\">What Are Centrifugal Pumps?<\/h2>\n\n<p class=\"wp-block-paragraph\">Centrifugal pumps are pumps in which the movement of the fluid is driven by torque generated by rotating mechanical components, commonly referred to as <strong>impellers<\/strong>.<\/p>\n\n<p class=\"wp-block-paragraph\">In practice, the fluid is set in motion by the rotating part and the internal geometry of the pump, which guide its flow from the Inlet to the Outlet.<\/p>\n\n<h2 id=\"i-componenti-principali-di-una-pompa-centrifuga\" class=\"wp-block-heading\">The Main Components of a Centrifugal Pump<\/h2>\n\n<p class=\"wp-block-paragraph\">The main components of a centrifugal pump are:<\/p>\n\n<ul class=\"wp-block-list\">\n<li><strong>Moving part (impeller)<\/strong>, which transfers energy to the fluid.<\/li>\n\n\n\n<li><strong>Pump housing (volute)<\/strong>, which channels the flow first into the inlet and then into the Outlet.<\/li>\n\n\n\n<li><strong>Shaft<\/strong> to which the impeller is attached; it is usually connected to the motor.<\/li>\n\n\n\n<li><strong>Engine<\/strong>, which can be <strong>electric<\/strong> or <strong>internal combustion<\/strong>.<\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\">This \u201cchain\u201d (motor \u2192 shaft \u2192 impeller \u2192 volute) is what makes it possible to convert energy and, consequently, to move the fluid through the system.<\/p>\n\n<h2 id=\"classificazione-e-installazione-orizzontale-verticale-e-condizioni-idrauliche\" class=\"wp-block-heading\">Classification and Installation (Horizontal\/Vertical and Hydraulic Conditions)<\/h2>\n\n<p class=\"wp-block-paragraph\">Depending on how <strong>the shaft<\/strong> and <strong>motor<\/strong> are positioned, the following types are distinguished:<\/p>\n\n<ul class=\"wp-block-list\">\n<li><strong>Horizontal Centrifugal Pumps<\/strong><\/li>\n\n\n\n<li><strong>Vertical Centrifugal Pumps<\/strong><\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\">In addition to their orientation, the pumps can be hydraulically positioned in two ways:<\/p>\n\n<ul class=\"wp-block-list\">\n<li><strong>BOTTOM HINGE<\/strong><\/li>\n\n\n\n<li><strong>OVERHANG<\/strong><\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\">These definitions are used to describe how the pump \u201cfits\u201d into the conditions of the circuit in which it operates, and thus to correctly contextualize the installation within the system.<\/p>\n\n<h2 id=\"come-funziona-una-pompa-centrifuga-principio-di-lavoro\" class=\"wp-block-heading\">How a Centrifugal Pump Works (Principle of Operation)<\/h2>\n\n<p class=\"wp-block-paragraph\">A centrifugal pump uses<strong>the centrifugal force<\/strong> of the impeller to move the fluid, converting <strong>mechanical<\/strong> energy (from a motor, which is usually electric) <strong>first into kinetic energy and then into pressure energy<\/strong>.<\/p>\n\n<p class=\"wp-block-paragraph\">The movement of the impeller creates a <strong>vacuum in the inlet pipe<\/strong>: the fluid, driven by <strong>atmospheric pressure<\/strong>, flows through the pipe and enters the pump. After drawing in the liquid, the impeller propels it toward the periphery using the centrifugal force generated by its speed. <\/p>\n\n<h2 id=\"girante-e-voluta-cosa-succede-al-fluido-dentro-la-pompa\" class=\"wp-block-heading\">Impeller and volute: what happens to the fluid inside the pump<\/h2>\n\n<p class=\"wp-block-paragraph\">The <strong>impeller<\/strong> of a centrifugal pump is equipped with a series of <strong>curved vanes<\/strong> that form channels with <strong>a cross-section that increases<\/strong> from the center toward the periphery.<\/p>\n\n<p class=\"wp-block-paragraph\">The fluid exits the impeller at a velocity <strong>Vt<\/strong>, so it still possesses <strong>kinetic energy<\/strong>, and enters the <strong>volute<\/strong>. The body of the centrifugal pump (the volute) is also constructed with an expanding cross-section, so that the remaining portion of the kinetic energy is converted into <strong>pressure energy<\/strong>. <\/p>\n\n<p class=\"wp-block-paragraph\">The result of this step is an increase in <strong>head<\/strong>, that is, the pump\u2019s ability to \u201covercome\u201d the resistance required by the system to move the fluid along the intended path.<\/p>\n\n<h2 id=\"curva-caratteristica-e-rendimento-di-una-pompa-centrifuga\" class=\"wp-block-heading\">Performance Curve and Efficiency of a Centrifugal Pump<\/h2>\n\n<p class=\"wp-block-paragraph\">The characteristics of a centrifugal pump are described by <strong>its performance curve<\/strong>, which shows how the <strong>head<\/strong> delivered by the pump varies as a function of <strong>the flow rate<\/strong> it is capable of delivering.<\/p>\n\n<p class=\"wp-block-paragraph\">This relationship is crucial because, in practice, the choice is not made \u201con a hunch\u201d: one verifies whether, at the required flow rate, the pump can provide the Head necessary for the system.<\/p>\n\n<h2 id=\"come-scegliere-la-pompa-portata-prevalenza-e-perdite-dellimpianto\" class=\"wp-block-heading\">How to Choose a Pump: Flow Rate, Head, and System Leaks<\/h2>\n\n<p class=\"wp-block-paragraph\">The choice of a pump must be based on the characteristics of the system you want to operate: <strong>flow rate and Head<\/strong>. In other words: <\/p>\n\n<ul class=\"wp-block-list\">\n<li>What is the <strong>flow rate (m\u00b3\/h)<\/strong> that must be achieved?;<\/li>\n\n\n\n<li>which <strong>obstacle<\/strong> must be overcome.<\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\">When calculating prevalence, it is necessary to take into account various factors related to the facility, including:<\/p>\n\n<ul class=\"wp-block-list\">\n<li><strong>The elevation difference<\/strong> that must be overcome to move the fluid from point A to point B (<em>geodetic height<\/em>);<\/li>\n\n\n\n<li><strong>Distributed leaks<\/strong> caused by the normal flow of fluid through the pipe;<\/li>\n\n\n\n<li><strong>Localized leaks<\/strong> caused by piping components along the line (such as <strong>valves<\/strong>, <strong>elbows<\/strong>, <strong>check valves<\/strong>, etc.).<\/li>\n<\/ul>\n\n<h2 id=\"caratteristiche-del-fluido-cosa-valutare-prima-della-scelta\" class=\"wp-block-heading\">Fluid Characteristics: What to Consider Before Making a Choice<\/h2>\n\n<p class=\"wp-block-paragraph\">In addition to the system&#8217;s characteristics, the characteristics of <strong>the fluid<\/strong> to be handled are also important. Specifically: <\/p>\n\n<ul class=\"wp-block-list\">\n<li><strong>Temperature<\/strong><\/li>\n\n\n\n<li><strong>Viscosity<\/strong><\/li>\n\n\n\n<li><strong>Density<\/strong><\/li>\n\n\n\n<li><strong>Presence or absence of particles<\/strong> in the fluid<\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\">These factors influence the selection because they describe \u201cwhat type of fluid\u201d the pump will need to handle, and thus the actual operating conditions of the system.<\/p>\n\n<h2 id=\"conclusione\" class=\"wp-block-heading\">Conclusion<\/h2>\n\n<p class=\"wp-block-paragraph\">To understand <em>how a centrifugal pump works<\/em>, follow the path of energy: the motor causes the impeller to rotate; the fluid enters through the inlet due to the vacuum created there; it gains kinetic energy; and then the volute converts this into pressure energy, increasing the Head. To select the most suitable pump, the key factors remain flow rate, head, system losses, and fluid characteristics. <\/p>\n","protected":false},"excerpt":{"rendered":"<p>How does a centrifugal pump work, and what are its components? In this clear explanation, you\u2019ll find the operating principle, performance curve, and parameters for selecting the right pump for your system. <\/p>\n","protected":false},"featured_media":5509,"parent":0,"template":"","meta":{"_acf_changed":false,"_angie_page":false,"footnotes":"","_members_access_role":[],"_members_access_error":""},"tags":[1141,1253,1258,1260,1259,1257,1261,1254,1255,1256],"class_list":["post-5508","esperto-risponde","type-esperto-risponde","status-publish","has-post-thumbnail","hentry","tag-centrifugal-pump","tag-centrifugal-pumps","tag-characteristic-curve","tag-concentrated-losses","tag-distributed-losses","tag-flow-rate","tag-fluid-systems","tag-impeller","tag-intentional","tag-prevalence"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/esperto-risponde\/5508","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/esperto-risponde"}],"about":[{"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/types\/esperto-risponde"}],"version-history":[{"count":0,"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/esperto-risponde\/5508\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/media\/5509"}],"wp:attachment":[{"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/media?parent=5508"}],"wp:term":[{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/tags?post=5508"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}