{"id":52,"date":"2025-10-31T00:25:51","date_gmt":"2025-10-31T00:25:51","guid":{"rendered":"https:\/\/vibromera.eu\/glossary\/bearing-span\/"},"modified":"2026-07-03T09:51:01","modified_gmt":"2026-07-03T09:51:01","slug":"bearing-span","status":"publish","type":"glossary","link":"https:\/\/vibromera.eu\/ta\/glossary\/bearing-span\/","title":{"rendered":"What is Bearing Span in Rotor Dynamics?"},"content":{"rendered":"<h1>Understanding Bearing Span in Rotor Dynamics<\/h1>\n\t\t<section class=\"woocommerce hestia-shop products is-shortcode\" id=\"products\" data-sorder=\"hestia_shop\" >\n\t\t\t\t\t\t<div class=\"\">\n\t\t\t\t\t\t<div class=\"hestia-shop-content\">\n\t\t\t<div class=\"row\" data-aos=\"fade-up\" >\t\t\t\t\t<div class=\"col-ms-6 col-sm-6 col-md-3 shop-item\">\n\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/ta\/product\/balanset-1\/\" class=\"woocommerce-LoopProduct-link woocommerce-loop-product__link\">\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"card-image\">\n\t\t\t\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/ta\/product\/balanset-1\/\" title=\"Portable balancer &amp; Vibration analyzer Balanset-1A\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"230\" height=\"153\" src=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/09\/77-e1693745667801-230x153.webp\" class=\"attachment-woocommerce_thumbnail size-woocommerce_thumbnail\" alt=\"Balanset-1A \u0bae\u0bc1\u0bb4\u0bc1\u0bae\u0bc8\u0baf\u0bbe\u0ba9 \u0b95\u0bbf\u0b9f\u0bcd \u0b9a\u0bc1\u0bae\u0bc8\u0baf\u0bc8 \u0b8e\u0b9f\u0bc8 \u0bae\u0bb1\u0bcd\u0bb1\u0bc1\u0bae\u0bcd \u0b85\u0ba4\u0bbf\u0bb0\u0bcd\u0bb5\u0bc1 \u0baa\u0b95\u0bc1\u0baa\u0bcd\u0baa\u0bbe\u0baf\u0bcd\u0bb5\u0bbf\" srcset=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/09\/77-e1693745667801-230x153.webp 230w, https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/09\/77-e1693745667801-18x12.webp 18w, https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/09\/77-e1693745667801-360x240.webp 360w, https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/09\/77-e1693745667801-272x182.webp 272w\" sizes=\"auto, (max-width: 230px) 100vw, 230px\" \/>\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t\t<div class=\"ripple-container\"><\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"content\">\n\t\t\t\t\t\t\t\t<span class=\"category\"><a href=\"https:\/\/vibromera.eu\/ta\/product-category\/devices\/\" rel=\"tag\">Devices<\/a><\/span>\n\t\t\t\t\t\t\t\t<h4 class=\"card-title\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"shop-item-title-link\" href=\"https:\/\/vibromera.eu\/ta\/product\/balanset-1\/\" title=\"Portable balancer &amp; Vibration analyzer Balanset-1A\">Portable balancer &amp; Vibration analyzer Balanset-1A<\/a>\n\n\t\t\t\t\t\t\t\t<\/h4>\n\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t<div class=\"footer\">\n\n\t\t\t\t\t\t\t\t\t<div class=\"price\"><h4><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">\u20ac<\/span>1,975.00<\/span> + VAT (\u0baa\u0bca\u0bb0\u0bc1\u0ba8\u0bcd\u0ba4\u0bc1\u0bae\u0bcd \u0b8e\u0ba9\u0bcd\u0bb1\u0bbe\u0bb2\u0bcd)<\/h4><\/div>\n\t\t\t\t\t\t\t\t\t<div class=\"stats\">\n\t\t\t\t\t\t\t\t\t\t<a rel=\"nofollow\" href=\"\/ta\/wp-json\/wp\/v2\/glossary\/52?add-to-cart=986\" data-quantity=\"1\" data-product_id=\"986\" data-product_sku=\"BS-1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart btn btn-just-icon btn-simple btn-default\" title=\"Add to cart\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Add to cart\" class=\"fas fa-cart-plus\" data-no-translation-data-original-title=\"\"><\/i><\/a>\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/a><a href=\"\/ta\/wp-json\/wp\/v2\/glossary\/52?add-to-cart=986\" aria-describedby=\"woocommerce_loop_add_to_cart_link_describedby_986\" data-quantity=\"1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart\" data-product_id=\"986\" data-product_sku=\"BS-1\" aria-label=\"Add to cart: \u201cPortable balancer &amp; Vibration analyzer Balanset-1A\u201d\" rel=\"nofollow\" data-success_message=\"\u201cPortable balancer &amp; Vibration analyzer Balanset-1A\u201d has been added to your cart\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Add to cart<\/a>\t<span id=\"woocommerce_loop_add_to_cart_link_describedby_986\" class=\"screen-reader-text\">\n\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t<div class=\"col-ms-6 col-sm-6 col-md-3 shop-item\">\n\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/ta\/product\/vibration-sensor\/\" class=\"woocommerce-LoopProduct-link woocommerce-loop-product__link\">\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"card-image\">\n\t\t\t\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/ta\/product\/vibration-sensor\/\" title=\"Vibration sensor\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"230\" height=\"153\" src=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-3-230x153.webp\" class=\"attachment-woocommerce_thumbnail size-woocommerce_thumbnail\" alt=\"Balanset-1A \u0b85\u0ba4\u0bbf\u0bb0\u0bcd\u0bb5\u0bc1 \u0b9a\u0bc6\u0ba9\u0bcd\u0b9a\u0bb0\u0bcd \u0ba8\u0bc6\u0bb0\u0bc1\u0b95\u0bcd\u0b95\u0bae\u0bbe\u0ba9 \u0baa\u0bbe\u0bb0\u0bcd\u0bb5\u0bc8\" srcset=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-3-230x153.webp 230w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-3-600x400.webp 600w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-3-300x200.webp 300w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-3-768x512.webp 768w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-3-1024x682.webp 1024w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-3-272x182.webp 272w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-3.webp 1280w\" sizes=\"auto, (max-width: 230px) 100vw, 230px\" \/>\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t\t<div class=\"ripple-container\"><\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"content\">\n\t\t\t\t\t\t\t\t<span class=\"category\"><a href=\"https:\/\/vibromera.eu\/ta\/product-category\/parts\/\" rel=\"tag\">Parts<\/a><\/span>\n\t\t\t\t\t\t\t\t<h4 class=\"card-title\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"shop-item-title-link\" href=\"https:\/\/vibromera.eu\/ta\/product\/vibration-sensor\/\" title=\"Vibration sensor\">Vibration sensor<\/a>\n\n\t\t\t\t\t\t\t\t<\/h4>\n\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t<div class=\"footer\">\n\n\t\t\t\t\t\t\t\t\t<div class=\"price\"><h4><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">\u20ac<\/span>90.00<\/span> + VAT (\u0baa\u0bca\u0bb0\u0bc1\u0ba8\u0bcd\u0ba4\u0bc1\u0bae\u0bcd \u0b8e\u0ba9\u0bcd\u0bb1\u0bbe\u0bb2\u0bcd)<\/h4><\/div>\n\t\t\t\t\t\t\t\t\t<div class=\"stats\">\n\t\t\t\t\t\t\t\t\t\t<a rel=\"nofollow\" href=\"\/ta\/wp-json\/wp\/v2\/glossary\/52?add-to-cart=1820\" data-quantity=\"1\" data-product_id=\"1820\" data-product_sku=\"VS-1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart btn btn-just-icon btn-simple btn-default\" title=\"Add to cart\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Add to cart\" class=\"fas fa-cart-plus\" data-no-translation-data-original-title=\"\"><\/i><\/a>\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/a><a href=\"\/ta\/wp-json\/wp\/v2\/glossary\/52?add-to-cart=1820\" aria-describedby=\"woocommerce_loop_add_to_cart_link_describedby_1820\" data-quantity=\"1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart\" data-product_id=\"1820\" data-product_sku=\"VS-1\" aria-label=\"Add to cart: \u201cVibration sensor\u201d\" rel=\"nofollow\" data-success_message=\"\u201cVibration sensor\u201d has been added to your cart\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Add to cart<\/a>\t<span id=\"woocommerce_loop_add_to_cart_link_describedby_1820\" class=\"screen-reader-text\">\n\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t<div class=\"col-ms-6 col-sm-6 col-md-3 shop-item\">\n\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/ta\/product\/optical-sensor-for-balanset-and-arbalance\/\" class=\"woocommerce-LoopProduct-link woocommerce-loop-product__link\">\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"card-image\">\n\t\t\t\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/ta\/product\/optical-sensor-for-balanset-and-arbalance\/\" title=\"Optical Sensor (Laser Tachometer)\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"230\" height=\"153\" src=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-230x153.webp\" class=\"attachment-woocommerce_thumbnail size-woocommerce_thumbnail\" alt=\"Optical Sensor (Laser Tachometer)\" srcset=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-230x153.webp 230w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-300x200.webp 300w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-1024x682.webp 1024w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-768x512.webp 768w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-1536x1023.webp 1536w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-18x12.webp 18w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-360x240.webp 360w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-460x306.webp 460w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-600x400.webp 600w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-272x182.webp 272w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU.webp 1600w\" sizes=\"auto, (max-width: 230px) 100vw, 230px\" \/>\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t\t<div class=\"ripple-container\"><\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"content\">\n\t\t\t\t\t\t\t\t<span class=\"category\"><a href=\"https:\/\/vibromera.eu\/ta\/product-category\/parts\/\" rel=\"tag\">Parts<\/a><\/span>\n\t\t\t\t\t\t\t\t<h4 class=\"card-title\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"shop-item-title-link\" href=\"https:\/\/vibromera.eu\/ta\/product\/optical-sensor-for-balanset-and-arbalance\/\" title=\"Optical Sensor (Laser Tachometer)\">Optical Sensor (Laser Tachometer)<\/a>\n\n\t\t\t\t\t\t\t\t<\/h4>\n\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t<div class=\"footer\">\n\n\t\t\t\t\t\t\t\t\t<div class=\"price\"><h4><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">\u20ac<\/span>124.00<\/span> + VAT (\u0baa\u0bca\u0bb0\u0bc1\u0ba8\u0bcd\u0ba4\u0bc1\u0bae\u0bcd \u0b8e\u0ba9\u0bcd\u0bb1\u0bbe\u0bb2\u0bcd)<\/h4><\/div>\n\t\t\t\t\t\t\t\t\t<div class=\"stats\">\n\t\t\t\t\t\t\t\t\t\t<a rel=\"nofollow\" href=\"\/ta\/wp-json\/wp\/v2\/glossary\/52?add-to-cart=1832\" data-quantity=\"1\" data-product_id=\"1832\" data-product_sku=\"Tach-1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart btn btn-just-icon btn-simple btn-default\" title=\"Add to cart\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Add to cart\" class=\"fas fa-cart-plus\" data-no-translation-data-original-title=\"\"><\/i><\/a>\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/a><a href=\"\/ta\/wp-json\/wp\/v2\/glossary\/52?add-to-cart=1832\" aria-describedby=\"woocommerce_loop_add_to_cart_link_describedby_1832\" data-quantity=\"1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart\" data-product_id=\"1832\" data-product_sku=\"Tach-1\" aria-label=\"Add to cart: \u201cOptical Sensor (Laser Tachometer)\u201d\" rel=\"nofollow\" data-success_message=\"\u201cOptical Sensor (Laser Tachometer)\u201d has been added to your cart\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Add to cart<\/a>\t<span id=\"woocommerce_loop_add_to_cart_link_describedby_1832\" class=\"screen-reader-text\">\n\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t<div class=\"col-ms-6 col-sm-6 col-md-3 shop-item\">\n\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/ta\/product\/balanset-4\/\" class=\"woocommerce-LoopProduct-link woocommerce-loop-product__link\">\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"card-image\">\n\t\t\t\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/ta\/product\/balanset-4\/\" title=\"Balanset-4\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"230\" height=\"153\" src=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/balkom4-230x153.webp\" class=\"attachment-woocommerce_thumbnail size-woocommerce_thumbnail\" alt=\"Vibromera \u0b9a\u0bc1\u0bae\u0bc8 \u0b9a\u0bae\u0ba8\u0bbf\u0bb2\u0bc8 \u0b95\u0bbf\u0b9f\u0bcd: \u0b95\u0bca\u0ba3\u0bcd\u0b9f \u0bb5\u0bb4\u0b95\u0bcd\u0b95\u0bc1, \u0baa\u0bb2-\u0b9a\u0948\u0ba9\u0bb2\u0bcd \u0b9a\u0bae\u0bbf\u0b95\u0bcd\u0b9e\u0bc8 \u0ba8\u0bbf\u09ac\u0ba8\u0bcd\u0ba4\u0b95\u0bb0\u0bcd, \u0b95\u0bc8\u0baf\u0bc1\u0bae\u0bc8\u0baf\u0bbe\u0ba9 \u0baa\u0b95\u0bc1\u0baa\u0bcd\u0baa\u0bbe\u0baf\u0bcd\u0bb5\u0bbf, \u0b95\u0bbe\u0ba8\u0bcd\u0ba4 \u0b85\u0b9f\u0bbf\u0baa\u0bcd\u0baa\u0b9f\u0bc8, \u0b85\u0ba4\u0bbf\u0bb0\u0bcd\u0bb5\u0bc1 \u0b9a\u0bc6\u0ba9\u0bcd\u0b9a\u0bb0\u0bcd\u0b95\u0bb3\u0bcd, \u0bae\u0bb1\u0bcd\u0bb1\u0bc1\u0bae\u0bcd \u0b9a\u0bc1\u0bb0\u0bc1\u0bb3\u0bbe\u0b95 \u0b95\u0bc7\u0baa\u0bbf\u0bb3\u0bcd\u0b95\u0bb3\u0bcd.\" srcset=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/balkom4-230x153.webp 230w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/balkom4-300x200.webp 300w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/balkom4-18x12.webp 18w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/balkom4-360x240.webp 360w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/balkom4-460x306.webp 460w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/balkom4-600x400.webp 600w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/balkom4-272x182.webp 272w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/balkom4.webp 640w\" sizes=\"auto, (max-width: 230px) 100vw, 230px\" \/>\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t\t<div class=\"ripple-container\"><\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"content\">\n\t\t\t\t\t\t\t\t<span class=\"category\"><a href=\"https:\/\/vibromera.eu\/ta\/product-category\/devices\/\" rel=\"tag\">Devices<\/a><\/span>\n\t\t\t\t\t\t\t\t<h4 class=\"card-title\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"shop-item-title-link\" href=\"https:\/\/vibromera.eu\/ta\/product\/balanset-4\/\" title=\"Balanset-4\">Balanset-4<\/a>\n\n\t\t\t\t\t\t\t\t<\/h4>\n\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t<div class=\"footer\">\n\n\t\t\t\t\t\t\t\t\t<div class=\"price\"><h4><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">\u20ac<\/span>6,803.00<\/span> + VAT (\u0baa\u0bca\u0bb0\u0bc1\u0ba8\u0bcd\u0ba4\u0bc1\u0bae\u0bcd \u0b8e\u0ba9\u0bcd\u0bb1\u0bbe\u0bb2\u0bcd)<\/h4><\/div>\n\t\t\t\t\t\t\t\t\t<div class=\"stats\">\n\t\t\t\t\t\t\t\t\t\t<a rel=\"nofollow\" href=\"\/ta\/wp-json\/wp\/v2\/glossary\/52?add-to-cart=1833\" data-quantity=\"1\" data-product_id=\"1833\" data-product_sku=\"BS-4\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart btn btn-just-icon btn-simple btn-default\" title=\"Add to cart\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Add to cart\" class=\"fas fa-cart-plus\" data-no-translation-data-original-title=\"\"><\/i><\/a>\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/a><a href=\"\/ta\/wp-json\/wp\/v2\/glossary\/52?add-to-cart=1833\" aria-describedby=\"woocommerce_loop_add_to_cart_link_describedby_1833\" data-quantity=\"1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart\" data-product_id=\"1833\" data-product_sku=\"BS-4\" aria-label=\"Add to cart: \u201cBalanset-4\u201d\" rel=\"nofollow\" data-success_message=\"\u201cBalanset-4\u201d has been added to your cart\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Add to cart<\/a>\t<span id=\"woocommerce_loop_add_to_cart_link_describedby_1833\" class=\"screen-reader-text\">\n\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div><!-- \/.row --><div class=\"row\">\t\t\t\t\t<div class=\"col-ms-6 col-sm-6 col-md-3 shop-item\">\n\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/ta\/product\/magnet-stand\/\" class=\"woocommerce-LoopProduct-link woocommerce-loop-product__link\">\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"card-image\">\n\t\t\t\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/ta\/product\/magnet-stand\/\" title=\"Magnetic Stand Insize-60-kgf\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"230\" height=\"153\" src=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36-230x153.webp\" class=\"attachment-woocommerce_thumbnail size-woocommerce_thumbnail\" alt=\"Magnet base.\" srcset=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36-230x153.webp 230w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36-600x400.webp 600w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36-300x200.webp 300w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36-1024x682.webp 1024w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36-768x512.webp 768w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36-360x240.webp 360w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36-272x182.webp 272w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36.webp 1280w\" sizes=\"auto, (max-width: 230px) 100vw, 230px\" \/>\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t\t<div class=\"ripple-container\"><\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"content\">\n\t\t\t\t\t\t\t\t<span class=\"category\"><a href=\"https:\/\/vibromera.eu\/ta\/product-category\/parts\/\" rel=\"tag\">Parts<\/a><\/span>\n\t\t\t\t\t\t\t\t<h4 class=\"card-title\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"shop-item-title-link\" href=\"https:\/\/vibromera.eu\/ta\/product\/magnet-stand\/\" title=\"Magnetic Stand Insize-60-kgf\">Magnetic Stand Insize-60-kgf<\/a>\n\n\t\t\t\t\t\t\t\t<\/h4>\n\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t<div class=\"footer\">\n\n\t\t\t\t\t\t\t\t\t<div class=\"price\"><h4><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">\u20ac<\/span>46.00<\/span> + VAT (\u0baa\u0bca\u0bb0\u0bc1\u0ba8\u0bcd\u0ba4\u0bc1\u0bae\u0bcd \u0b8e\u0ba9\u0bcd\u0bb1\u0bbe\u0bb2\u0bcd)<\/h4><\/div>\n\t\t\t\t\t\t\t\t\t<div class=\"stats\">\n\t\t\t\t\t\t\t\t\t\t<a rel=\"nofollow\" href=\"\/ta\/wp-json\/wp\/v2\/glossary\/52?add-to-cart=1852\" data-quantity=\"1\" data-product_id=\"1852\" data-product_sku=\"MS-1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart btn btn-just-icon btn-simple btn-default\" title=\"Add to cart\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Add to cart\" class=\"fas fa-cart-plus\" data-no-translation-data-original-title=\"\"><\/i><\/a>\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/a><a href=\"\/ta\/wp-json\/wp\/v2\/glossary\/52?add-to-cart=1852\" aria-describedby=\"woocommerce_loop_add_to_cart_link_describedby_1852\" data-quantity=\"1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart\" data-product_id=\"1852\" data-product_sku=\"MS-1\" aria-label=\"Add to cart: \u201cMagnetic Stand Insize-60-kgf\u201d\" rel=\"nofollow\" data-success_message=\"\u201cMagnetic Stand Insize-60-kgf\u201d has been added to your cart\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Add to cart<\/a>\t<span id=\"woocommerce_loop_add_to_cart_link_describedby_1852\" class=\"screen-reader-text\">\n\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t<div class=\"col-ms-6 col-sm-6 col-md-3 shop-item\">\n\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/ta\/product\/reflective-tape\/\" class=\"woocommerce-LoopProduct-link woocommerce-loop-product__link\">\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"card-image\">\n\t\t\t\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/ta\/product\/reflective-tape\/\" title=\"Reflective tape\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"230\" height=\"153\" src=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/05\/s-l1600-230x153.webp\" class=\"attachment-woocommerce_thumbnail size-woocommerce_thumbnail\" alt=\"Reflective tape\" srcset=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/05\/s-l1600-230x153.webp 230w, https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/05\/s-l1600-16x12.webp 16w, https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/05\/s-l1600-360x240.webp 360w, https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/05\/s-l1600-460x306.webp 460w, https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/05\/s-l1600-272x182.webp 272w\" sizes=\"auto, (max-width: 230px) 100vw, 230px\" \/>\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t\t<div class=\"ripple-container\"><\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"content\">\n\t\t\t\t\t\t\t\t<span class=\"category\"><a href=\"https:\/\/vibromera.eu\/ta\/product-category\/parts\/\" rel=\"tag\">Parts<\/a><\/span>\n\t\t\t\t\t\t\t\t<h4 class=\"card-title\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"shop-item-title-link\" href=\"https:\/\/vibromera.eu\/ta\/product\/reflective-tape\/\" title=\"Reflective tape\">Reflective tape<\/a>\n\n\t\t\t\t\t\t\t\t<\/h4>\n\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t<div class=\"footer\">\n\n\t\t\t\t\t\t\t\t\t<div class=\"price\"><h4><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">\u20ac<\/span>10.00<\/span> + VAT (\u0baa\u0bca\u0bb0\u0bc1\u0ba8\u0bcd\u0ba4\u0bc1\u0bae\u0bcd \u0b8e\u0ba9\u0bcd\u0bb1\u0bbe\u0bb2\u0bcd)<\/h4><\/div>\n\t\t\t\t\t\t\t\t\t<div class=\"stats\">\n\t\t\t\t\t\t\t\t\t\t<a rel=\"nofollow\" href=\"\/ta\/wp-json\/wp\/v2\/glossary\/52?add-to-cart=2329\" data-quantity=\"1\" data-product_id=\"2329\" data-product_sku=\"rt-1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart btn btn-just-icon btn-simple btn-default\" title=\"Add to cart\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Add to cart\" class=\"fas fa-cart-plus\" data-no-translation-data-original-title=\"\"><\/i><\/a>\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/a><a href=\"\/ta\/wp-json\/wp\/v2\/glossary\/52?add-to-cart=2329\" aria-describedby=\"woocommerce_loop_add_to_cart_link_describedby_2329\" data-quantity=\"1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart\" data-product_id=\"2329\" data-product_sku=\"rt-1\" aria-label=\"Add to cart: \u201cReflective tape\u201d\" rel=\"nofollow\" data-success_message=\"\u201cReflective tape\u201d has been added to your cart\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Add to cart<\/a>\t<span id=\"woocommerce_loop_add_to_cart_link_describedby_2329\" class=\"screen-reader-text\">\n\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t<div class=\"col-ms-6 col-sm-6 col-md-3 shop-item\">\n\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/ta\/product\/dynamic-balancer-balanset-1a\/\" class=\"woocommerce-LoopProduct-link woocommerce-loop-product__link\">\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"card-image\">\n\t\t\t\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/ta\/product\/dynamic-balancer-balanset-1a\/\" title=\"Dynamic balancer \u201cBalanset-1A\u201d OEM\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"230\" height=\"153\" src=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-230x153.webp\" class=\"attachment-woocommerce_thumbnail size-woocommerce_thumbnail\" alt=\"Balanset-1A \u0b95\u0bbf\u0b9f\u0bcd \u0b89\u0bb3\u0bcd\u0bb3\u0b9f\u0b95\u0bcd\u0b95\u0bae\u0bcd \u0b87\u0b9f\u0bc8\u0bae\u0bc1\u0b95 \u0b85\u0bb2\u0b95\u0bc1, \u0b9a\u0bc6\u0ba9\u0bcd\u0b9a\u0bb0\u0bcd\u0b95\u0bb3\u0bcd, tachometer \u0bae\u0bb1\u0bcd\u0bb1\u0bc1\u0bae\u0bcd \u0b85\u0ba3\u0bc1\u0b95\u0bc2\u0b9f\u0bc1\" srcset=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-230x153.webp 230w, https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-600x400.webp 600w, https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-300x200.webp 300w, https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-1024x683.webp 1024w, https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-768x512.webp 768w, https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-1536x1024.webp 1536w, https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-2048x1366.webp 2048w, https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-360x240.webp 360w, https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-272x182.webp 272w, https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-e1732998877834.webp 708w\" sizes=\"auto, (max-width: 230px) 100vw, 230px\" \/>\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t\t<div class=\"ripple-container\"><\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"content\">\n\t\t\t\t\t\t\t\t<span class=\"category\"><a href=\"https:\/\/vibromera.eu\/ta\/product-category\/devices\/\" rel=\"tag\">Devices<\/a><\/span>\n\t\t\t\t\t\t\t\t<h4 class=\"card-title\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"shop-item-title-link\" href=\"https:\/\/vibromera.eu\/ta\/product\/dynamic-balancer-balanset-1a\/\" title=\"Dynamic balancer \u201cBalanset-1A\u201d OEM\">Dynamic balancer \u201cBalanset-1A\u201d OEM<\/a>\n\n\t\t\t\t\t\t\t\t<\/h4>\n\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t<div class=\"footer\">\n\n\t\t\t\t\t\t\t\t\t<div class=\"price\"><h4><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">\u20ac<\/span>1,735.00<\/span> + VAT (\u0baa\u0bca\u0bb0\u0bc1\u0ba8\u0bcd\u0ba4\u0bc1\u0bae\u0bcd \u0b8e\u0ba9\u0bcd\u0bb1\u0bbe\u0bb2\u0bcd)<\/h4><\/div>\n\t\t\t\t\t\t\t\t\t<div class=\"stats\">\n\t\t\t\t\t\t\t\t\t\t<a rel=\"nofollow\" href=\"\/ta\/wp-json\/wp\/v2\/glossary\/52?add-to-cart=4193\" data-quantity=\"1\" data-product_id=\"4193\" data-product_sku=\"BS-1OEM\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart btn btn-just-icon btn-simple btn-default\" title=\"Add to cart\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Add to cart\" class=\"fas fa-cart-plus\" data-no-translation-data-original-title=\"\"><\/i><\/a>\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/a><a href=\"\/ta\/wp-json\/wp\/v2\/glossary\/52?add-to-cart=4193\" aria-describedby=\"woocommerce_loop_add_to_cart_link_describedby_4193\" data-quantity=\"1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart\" data-product_id=\"4193\" data-product_sku=\"BS-1OEM\" aria-label=\"Add to cart: \u201cDynamic balancer \u201cBalanset-1A\u201d OEM\u201d\" rel=\"nofollow\" data-success_message=\"\u201cDynamic balancer \u201cBalanset-1A\u201d OEM\u201d has been added to your cart\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Add to cart<\/a>\t<span id=\"woocommerce_loop_add_to_cart_link_describedby_4193\" class=\"screen-reader-text\">\n\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/section>\n\t\t\n<p><strong>Bearing span<\/strong> \u2014 also called bearing spacing or support span \u2014 is the centre-to-centre distance between the two main support bearings of a <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/rotor\/\">\u0b9a\u0bc1\u0bb4\u0bb2\u0bbf<\/a>. Plain as it sounds, this single dimension is one of the most influential parameters in all of <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/rotor-dynamics\/\">rotor dynamics<\/a>, because it sets the shaft&#8217;s bending <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/stiffness\/\">stiffness<\/a>, and stiffness in turn governs the <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/critical-speed\/\">\u0bae\u0bc1\u0b95\u0bcd\u0b95\u0bbf\u0baf \u0bb5\u0bc7\u0b95\u0b99\u0bcd\u0b95\u0bb3\u0bcd<\/a>, the maximum deflections, the loads carried by the bearings, and the rotor&#8217;s whole dynamic character. For a given shaft diameter and material, lengthening the span makes the shaft more flexible and lowers its critical speeds; shortening it stiffens the shaft and raises them. That lever \u2014 large effect from a modest geometric change \u2014 is what makes bearing span a key design decision rather than an afterthought.<\/p>\n<h2>1. Definition and First Principles<\/h2>\n<p>Between its two supports, a shaft behaves like a simply supported beam, and the same mechanics that govern any beam govern the rotor. The span is the beam&#8217;s length, and because beam deflection scales with the cube of length, the rotor&#8217;s flexibility is acutely sensitive to where the bearings sit. Everything that follows \u2014 critical speeds, deflection limits, bearing loads \u2014 flows from that cubic relationship, so it is worth establishing it carefully before drawing design conclusions.<\/p>\n<h2>2. Effect on Rotor Stiffness<\/h2>\n<h3>The beam-mechanics relationship<\/h3>\n<p>The stiffness of the shaft between bearings follows the fundamental beam equation:<\/p>\n<blockquote><p><strong>Deflection \u221d L\u00b3 \/ (E \u00d7 I)<\/strong><\/p><\/blockquote>\n<ul>\n<li><strong>L<\/strong> = bearing span (length).<\/li>\n<li><strong>E<\/strong> = the material&#8217;s modulus of elasticity.<\/li>\n<li><strong>I<\/strong> = the shaft&#8217;s area moment of inertia, itself proportional to diameter\u2074.<\/li>\n<li><strong>Key insight:<\/strong> deflection \u2014 and therefore flexibility \u2014 increases with the <em>cube<\/em> of the span.<\/li>\n<\/ul>\n<h3>Practical implications<\/h3>\n<ul>\n<li>Doubling the bearing span increases deflection eightfold (2\u00b3 = 8).<\/li>\n<li>Reducing the span by 25% cuts deflection by roughly 58%.<\/li>\n<li>Small changes in bearing location can have outsized effects on stiffness.<\/li>\n<li>For long rotors, span is a more powerful lever than shaft diameter \u2014 though, since I scales with diameter\u2074, diameter is the stronger lever when both can be changed.<\/li>\n<\/ul>\n<h2>3. Impact on Critical Speeds<\/h2>\n<h3>The fundamental relationship<\/h3>\n<p>For a simple rotor \u2014 a uniform shaft with a concentrated mass at its centre \u2014 the first <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/natural-frequency\/\">\u0b87\u0baf\u0bb2\u0bcd\u0baa\u0bc1 \u0b85\u0ba4\u0bbf\u0bb0\u0bcd\u0bb5\u0bc6\u0ba3\u0bcd<\/a> is approximately:<\/p>\n<ul>\n<li><strong>f \u221d \u221a(k\/m)<\/strong>, where k is shaft stiffness and m is rotor mass.<\/li>\n<li>Since stiffness \u221d 1\/L\u00b3, it follows that <strong>f \u221d 1\/L<sup>3\/2<\/sup><\/strong>.<\/li>\n<li><strong>Practical rule:<\/strong> the first critical speed varies inversely with bearing span raised to the 1.5 power.<\/li>\n<\/ul>\n<h3>Design implications<\/h3>\n<ul>\n<li><strong>Shorter span:<\/strong> higher critical speeds, a stiffer rotor, better suited to high-speed operation.<\/li>\n<li><strong>Longer span:<\/strong> lower critical speeds, a more flexible rotor that may have to run as a <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/flexible-rotor\/\">flexible rotor<\/a>.<\/li>\n<li><strong>Optimisation:<\/strong> a trade-off between accessibility (a longer span eases assembly) and stiffness (a shorter span performs better dynamically).<\/li>\n<\/ul>\n<h3>Worked example<\/h3>\n<p>Take a motor rotor with a first critical speed of 3000 RPM at a 500 mm bearing span:<\/p>\n<ul>\n<li>Increase the span to 600 mm (a 20% increase).<\/li>\n<li>The critical speed falls to 3000 \/ (600\/500)<sup>1.5<\/sup> \u2248 2280 RPM.<\/li>\n<li>That 24% drop could move the critical speed dangerously close to operating speed \u2014 exactly the kind of shift worth checking against running speed with a <a href=\"https:\/\/vibromera.eu\/ta\/calculators\/rotor-critical-speed\/\">\u0ba4\u0ba3\u0bcd\u0b9f\u0bc1 \u0ba8\u0bbf\u0baf\u0bae\u0b95 \u0bb5\u0bc7\u0b95 \u0b95\u0ba3\u0b95\u0bcd\u0b95\u0bc6\u0b9f\u0bc1\u0baa\u0bcd\u0baa\u0bbf<\/a>.<\/li>\n<\/ul>\n<h2>4. \u0bb5\u0b9f\u0bbf\u0bb5\u0bae\u0bc8\u0baa\u0bcd\u0baa\u0bc1 \u0b95\u0bb0\u0bc1\u0ba4\u0bcd\u0ba4\u0b99\u0bcd\u0b95\u0bb3\u0bcd<\/h2>\n<p>Positioning bearings means reconciling several competing demands at once.<\/p>\n<h3>Mechanical constraints<\/h3>\n<ul>\n<li>Machine frame and housing dimensions.<\/li>\n<li>The locations of rotor components such as impellers and couplings.<\/li>\n<li>Access for maintenance and assembly.<\/li>\n<li>Coupling and drive requirements.<\/li>\n<\/ul>\n<h3>Rotor-dynamic requirements<\/h3>\n<ul>\n<li><strong>Critical-speed separation:<\/strong> place the bearings so critical speeds sit \u00b120\u201330% away from operating speed.<\/li>\n<li><strong>Rigid versus flexible:<\/strong> a shorter span keeps the rotor <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/rigid-rotor\/\">rigid<\/a>; a longer span may force operation as a flexible rotor.<\/li>\n<li><strong>Deflection limits:<\/strong> keep maximum deflection below the point where it causes rubs or seal damage.<\/li>\n<li><strong>Bearing loads:<\/strong> longer spans reduce static bearing loads for a given rotor weight.<\/li>\n<\/ul>\n<h3>Manufacturing and assembly<\/h3>\n<ul>\n<li>Longer spans give more room for balancing and assembly.<\/li>\n<li>Bearing alignment is easier when the span is open and visible.<\/li>\n<li>Shorter spans are more compact and need less frame material.<\/li>\n<\/ul>\n<h2>5. Effect on Bearing Loads<\/h2>\n<h3>Static load distribution<\/h3>\n<p>Bearing span shapes how rotor weight and forces share out between the two supports:<\/p>\n<ul>\n<li><strong>Longer span:<\/strong> lower bearing loads for the same rotor weight, thanks to the longer lever arm.<\/li>\n<li><strong>Shorter span:<\/strong> higher individual loads but more even distribution.<\/li>\n<li><strong>Overhung loads:<\/strong> the effect of an <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/overhung-rotor\/\">overhung component<\/a> is amplified as the span lengthens.<\/li>\n<\/ul>\n<h3>Dynamic loads from unbalance<\/h3>\n<ul>\n<li>Dynamic bearing loads from <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/unbalance\/\">unbalance<\/a> depend on deflection.<\/li>\n<li>A longer span allows more deflection, which can lower the transmitted bearing load.<\/li>\n<li>But that same deflection raises the vibration amplitude.<\/li>\n<li>The designer therefore trades bearing life against vibration level \u2014 a balance that good <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/balancing\/\">\u0b9a\u0bae\u0ba8\u0bbf\u0bb2\u0bc8\u0baa\u0bcd\u0baa\u0b9f\u0bc1\u0ba4\u0bcd\u0ba4\u0bc1\u0ba4\u0bb2\u0bcd<\/a> shifts in everyone&#8217;s favour by cutting the excitation itself.<\/li>\n<\/ul>\n<h2>6. Relationship to Shaft Diameter<\/h2>\n<p>Span is never chosen in isolation; it must be weighed together with shaft diameter.<\/p>\n<h3>Span-to-diameter ratio (L\/D)<\/h3>\n<ul>\n<li><strong>L\/D &lt; 5:<\/strong> very stiff, with rigid-rotor behaviour the norm.<\/li>\n<li><strong>5 &lt; L\/D &lt; 20:<\/strong> moderate flexibility, covering most industrial machinery.<\/li>\n<li><strong>L\/D &gt; 20:<\/strong> highly flexible, where flexible-rotor considerations become essential.<\/li>\n<\/ul>\n<h3>Optimisation strategy<\/h3>\n<ul>\n<li><strong>Fixed span:<\/strong> increase diameter to raise the critical speeds.<\/li>\n<li><strong>Fixed diameter:<\/strong> decrease span to raise them.<\/li>\n<li><strong>Combined optimisation:<\/strong> adjust both to meet critical-speed and deflection targets together.<\/li>\n<li><strong>Practical limit:<\/strong> space constraints usually fix one parameter, leaving the other as the only free variable.<\/li>\n<\/ul>\n<h2>7. Multiple-Bearing Configurations<\/h2>\n<h3>Standard two-bearing support<\/h3>\n<ul>\n<li>The most common arrangement.<\/li>\n<li>A single span defines the system.<\/li>\n<li>Analysis and design are straightforward.<\/li>\n<\/ul>\n<h3>Multi-bearing systems<\/h3>\n<p>Rotors with more than two bearings have more than one span to reckon with:<\/p>\n<ul>\n<li><strong>Three bearings:<\/strong> two spans \u2014 for example, a motor with an additional centre bearing.<\/li>\n<li><strong>Four or more:<\/strong> multiple spans demanding more complex analysis.<\/li>\n<li><strong>Effective span:<\/strong> for vibration work, each <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/mode-shape\/\">mode shape<\/a> may have its own effective span.<\/li>\n<li><strong>Coupled dynamics:<\/strong> the spans interact, shaping the overall system behaviour.<\/li>\n<\/ul>\n<h2>8. Measurement, Verification, and Retrofits<\/h2>\n<h3>As-built verification<\/h3>\n<ul>\n<li>Measure the actual bearing span during installation.<\/li>\n<li>Confirm it matches the design specification, typically to within \u00b15 mm.<\/li>\n<li>Record the as-built dimensions for the rotor-dynamic calculations.<\/li>\n<li>Check the alignment of the bearing centrelines.<\/li>\n<\/ul>\n<h3>Effect of installation variations<\/h3>\n<ul>\n<li>Bearing-position errors shift the predicted critical speeds.<\/li>\n<li>Misalignment introduces additional loads.<\/li>\n<li>Foundation settling can change the effective span over time.<\/li>\n<li>Thermal growth may alter the effective span at operating temperature.<\/li>\n<\/ul>\n<h3>When to modify bearing span<\/h3>\n<p>Repositioning a bearing is considered when:<\/p>\n<ul>\n<li>The machine runs too close to a critical speed.<\/li>\n<li>Excessive shaft deflection is causing rubs or seal problems.<\/li>\n<li>Bearing loads are too high or unevenly shared.<\/li>\n<li>The design is shifting between rigid- and flexible-rotor operation.<\/li>\n<\/ul>\n<h3>Challenges of span modification<\/h3>\n<ul>\n<li><strong>Structural changes:<\/strong> frame or housing modifications may be needed.<\/li>\n<li><strong>Alignment impact:<\/strong> moving a bearing affects alignment with the driven equipment.<\/li>\n<li><strong>Cost:<\/strong> significant modification expense must be justified by the benefit.<\/li>\n<li><strong>Validation:<\/strong> testing is required to confirm the improvement \u2014 including a re-check of the residual <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/vibration\/\">vibration<\/a> after the change. A portable analyser like the <a href=\"https:\/\/vibromera.eu\/ta\/product\/balanset-1\/\">Balanset-1A<\/a> makes that confirmation straightforward, capturing the bearing vibration and critical-speed behaviour on-site so the retrofit can be signed off against measured data rather than prediction alone.<\/li>\n<\/ul>\n<p>Bearing span is a fundamental geometric parameter that profoundly shapes rotor dynamic behaviour. Choosing it well during design and verifying it accurately during installation are essential to achieving the critical-speed separation, acceptable vibration levels, and reliable long-term operation that every rotating machine depends on.<\/p>\n<hr>\n<p><a href=\"https:\/\/vibromera.eu\/ta\/glossary\/\">\u2190 \u0bae\u0bc1\u0ba4\u0ba9\u0bcd\u0bae\u0bc8 \u0b85\u0b9f\u0bcd\u0b9f\u0bb5\u0ba3\u0bc8\u0b95\u0bcd\u0b95\u0bc1 \u0ba4\u0bbf\u0bb0\u0bc1\u0bae\u0bcd\u0baa\u0bb5\u0bc1\u0bae\u0bcd<\/a><\/p>","protected":false},"excerpt":{"rendered":"<p>Learn about bearing span, the distance between rotor support bearings that critically affects shaft stiffness, critical speeds, and deflection characteristics in rotating machinery.<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[109,111],"tags":[],"class_list":["post-52","glossary","type-glossary","status-publish","hentry","category-glossary","category-rotor-balancing"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/ta\/wp-json\/wp\/v2\/glossary\/52","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vibromera.eu\/ta\/wp-json\/wp\/v2\/glossary"}],"about":[{"href":"https:\/\/vibromera.eu\/ta\/wp-json\/wp\/v2\/types\/glossary"}],"version-history":[{"count":2,"href":"https:\/\/vibromera.eu\/ta\/wp-json\/wp\/v2\/glossary\/52\/revisions"}],"predecessor-version":[{"id":102151,"href":"https:\/\/vibromera.eu\/ta\/wp-json\/wp\/v2\/glossary\/52\/revisions\/102151"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/ta\/wp-json\/wp\/v2\/media?parent=52"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/ta\/wp-json\/wp\/v2\/categories?post=52"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/ta\/wp-json\/wp\/v2\/tags?post=52"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}