{"id":232,"date":"2025-10-31T00:25:51","date_gmt":"2025-10-31T00:25:51","guid":{"rendered":"https:\/\/vibromera.eu\/glossary\/shaft-bow\/"},"modified":"2026-05-23T23:06:20","modified_gmt":"2026-05-23T23:06:20","slug":"shaft-bow","status":"publish","type":"glossary","link":"https:\/\/vibromera.eu\/ta\/glossary\/shaft-bow\/","title":{"rendered":"What is Shaft Bow? Causes, Detection, and Correction"},"content":{"rendered":"<h1>Understanding Shaft Bow in Rotating Machinery<\/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\/232?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\/232?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\/232?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\/232?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\/232?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\/232?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\/232?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\/232?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\/232?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\/232?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\/232?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\/232?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\/232?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\/232?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>Shaft bow<\/strong> (also called shaft bending, rotor bow, or simply &#8220;bow&#8221;) is a condition where a <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/rotor\/\">\u0b9a\u0bc1\u0bb4\u0bb2\u0bbf<\/a> shaft has developed a permanent or semi-permanent curvature, causing its geometric centreline to deviate from a straight line between the bearing journals. Unlike temporary <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/run-out\/\">run-out<\/a> caused by a loose component or an eccentric mounting, shaft bow represents an actual deformation of the shaft material itself. It produces <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/vibration\/\">vibration<\/a> symptoms that superficially resemble <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/unbalance\/\">unbalance<\/a> \u2014 strong, synchronous, once-per-revolution motion \u2014 yet it cannot be cured by conventional <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>. Recognising that distinction early is what separates a quick repair from days of fruitless balancing on a shaft that was never going to respond.<\/p>\n<h2>1. Definition: What Shaft Bow Really Is<\/h2>\n<p>A perfectly healthy rotor has a mass axis and a geometric axis that are both straight and very nearly coincident. Shaft bow breaks that picture by bending the geometric axis into an arc. The bend may be small \u2014 a few hundredths of a millimetre is enough to matter on a high-speed machine \u2014 but because the bowed centreline no longer passes through the bearing centres, the rotor is forced to whirl about a line it does not naturally want to spin around.<\/p>\n<p>It is worth separating bow from its close relatives. A <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/bent-shaft\/\">bent shaft<\/a> is essentially the same fault described from the mechanical side, while <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/eccentricity\/\">eccentricity<\/a> describes a rotor whose mass centre is offset without the shaft itself being curved. True <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/run-out\/\">run-out<\/a> can be mechanical (a real geometric deviation) or electrical (a false reading from a <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/proximity-probe\/\">\uadfc\uc811 \ud0d0\uce68<\/a> seeing material or magnetic variation). Shaft bow is specifically a geometric deformation of the shaft body, and that is why no amount of added mass elsewhere can truly &#8220;balance it out.&#8221;<\/p>\n<h2>2. Types of Shaft Bow<\/h2>\n<p>Shaft bow is best categorised by its cause and how long it persists, because each type calls for a different response.<\/p>\n<h3>2.1 Permanent Mechanical Bow<\/h3>\n<p>This is plastic (permanent) deformation of the shaft material \u2014 the metal has yielded and will not spring back. Common origins include:<\/p>\n<ul>\n<li>Mechanical overload or impact<\/li>\n<li>Improper lifting or handling during maintenance<\/li>\n<li>Dropping the rotor<\/li>\n<li>Excessive bending stress during operation<\/li>\n<li>Manufacturing defects or improper heat treatment<\/li>\n<\/ul>\n<p>Once the shaft has yielded, the bow remains even when the shaft is at rest and every external load has been removed. This is the signature that separates permanent bow from the thermal kind: it is present cold, and it is present on the bench.<\/p>\n<h3>2.2 Thermal Bow (Transient)<\/h3>\n<p>Also called <strong>thermal bow<\/strong> \u0b85\u0bb2\u0bcd\u0bb2\u0ba4\u0bc1 <strong>hot bow<\/strong>, this is a temporary condition caused by uneven heating around the shaft circumference. The hotter side expands more than the cooler side, forcing the shaft into a curve with the hot side on the convex (outer) face. Typical triggers are:<\/p>\n<ul>\n<li>Asymmetric heat sources (hot process fluid on one side, cooling air on the other)<\/li>\n<li>Bearing friction heating one side of the shaft<\/li>\n<li>Rotor rubs generating localised heating<\/li>\n<li>Solar heating on outdoor equipment<\/li>\n<li>Improper warm-up procedures for large turbines<\/li>\n<\/ul>\n<p>Thermal bow normally disappears once the shaft cools uniformly or reaches thermal equilibrium. The full mechanism, prevention, and turning-gear practice are covered in depth under <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/thermal-bow\/\">thermal bow<\/a>. The important caution here is that repeated thermal-bow cycles can eventually drive a shaft past its yield point and leave a permanent set \u2014 so a &#8220;temporary&#8221; problem ignored for long enough becomes a permanent one.<\/p>\n<h3>2.3 Residual Stress Bow<\/h3>\n<p>Internal residual stresses left by welding, heat treatment, or machining can cause a shaft to bow slowly over time, particularly when service temperatures or operating loads allow those locked-in stresses to relax. This kind of bow can appear months or years after commissioning, which makes periodic straightness checks worthwhile on critical rotors.<\/p>\n<h2>3. Causes of Shaft Bow<\/h2>\n<p>Understanding the root cause both prevents recurrence and points to the right correction. The drivers fall into three families.<\/p>\n<h3>3.1 Mechanical Causes<\/h3>\n<ul>\n<li><strong>Overload:<\/strong> operating at loads exceeding design limits.<\/li>\n<li><strong>Improper storage:<\/strong> storing shafts horizontally without proper support, allowing creep sag over time \u2014 especially on long, slender rotors left for months on two end supports.<\/li>\n<li><strong>Mishandling:<\/strong> lifting by the shaft instead of the designated lifting points.<\/li>\n<li><strong>Accident or impact:<\/strong> dropping, collision, or foreign-object damage.<\/li>\n<li><strong>Bearing seizure:<\/strong> a seized bearing can cause the shaft to bend under the driving torque.<\/li>\n<\/ul>\n<h3>3.2 Thermal Causes<\/h3>\n<ul>\n<li><strong>Uneven heating:<\/strong> non-uniform temperature distribution around the shaft circumference.<\/li>\n<li><strong>Rapid temperature changes:<\/strong> thermal shock during startup or shutdown.<\/li>\n<li><strong>Hot spots:<\/strong> localised heating from friction, rubs, or process conditions.<\/li>\n<li><strong>Inadequate warm-up:<\/strong> starting cold turbines or large machines too quickly.<\/li>\n<li><strong>Shutdown procedures:<\/strong> allowing a hot shaft to stop rotating before it cools (thermal sag).<\/li>\n<\/ul>\n<h3>3.3 Material and Manufacturing Causes<\/h3>\n<ul>\n<li><strong>Poor material quality:<\/strong> inclusions, voids, or material inhomogeneities.<\/li>\n<li><strong>\u0ba4\u0bb5\u0bb1\u0bbe\u0ba9 \u0bb5\u0bc6\u0baa\u0bcd\u0baa \u0b9a\u0bbf\u0b95\u0bbf\u0b9a\u0bcd\u0b9a\u0bc8 (Improper heat treatment):<\/strong> residual stresses from quenching or tempering.<\/li>\n<li><strong>Welding distortion:<\/strong> asymmetric welding creating residual stresses.<\/li>\n<li><strong>Machining stresses:<\/strong> stresses induced during manufacturing that relax in service.<\/li>\n<\/ul>\n<h2>4. How Shaft Bow Causes Vibration<\/h2>\n<p>A bowed shaft generates vibration through two distinct but cooperating mechanisms.<\/p>\n<h3>4.1 Geometric Unbalance<\/h3>\n<p>When a bowed shaft rotates, its curved centreline sweeps out a cone or other non-circular path. Even if the rotor&#8217;s mass distribution is perfectly even, the bowed geometry behaves like an eccentric rotating mass: it throws the centre of gravity off the spin axis and generates a <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/centrifugal-force\/\">\u0bae\u0bc8\u0baf\u0bb5\u0bbf\u0bb2\u0b95\u0bcd\u0b95\u0bc1 \u0bb5\u0bbf\u0b9a\u0bc8<\/a> that rises with the square of speed, producing strong 1\u00d7 vibration at <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/running-speed\/\">running speed<\/a>. This is precisely why bow masquerades as unbalance in the spectrum.<\/p>\n<h3>4.2 Moment Loading on the Bearings<\/h3>\n<p>The curvature also imposes a static and rotating bending moment that is fed straight into the bearings, causing fluctuating bearing loads and seat vibration. On larger rotors this moment loading is what drives accelerated bearing wear and, in extreme cases, contact between the rotor and stationary seals. A heavily bowed rotor whose bow sits near a <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/critical-speed\/\">critical speed<\/a> can produce an amplified, sometimes alarming, response on run-up.<\/p>\n<h2>5. Detecting Shaft Bow<\/h2>\n<p>Because bow and genuine mass unbalance share the same 1\u00d7 signature, distinguishing them is the crux of the diagnosis. The most powerful discriminator is behaviour at very low speed and during temperature change.<\/p>\n<h3>5.1 Symptom Comparison: Bow vs Unbalance<\/h3>\n<table border=\"1\" style=\"width:100%; border-collapse:collapse;\">\n<tr>\n<th>Characteristic<\/th>\n<th>Unbalance<\/th>\n<th>Shaft Bow<\/th>\n<\/tr>\n<tr>\n<td>Vibration Frequency<\/td>\n<td>1\u00d7 \u0b87\u0baf\u0b95\u0bcd\u0b95 \u0bb5\u0bc7\u0b95\u0bae\u0bcd<\/td>\n<td>1\u00d7 \u0b87\u0baf\u0b95\u0bcd\u0b95 \u0bb5\u0bc7\u0b95\u0bae\u0bcd<\/td>\n<\/tr>\n<tr>\n<td>\u0b95\u0b9f\u0bcd\u0b9f \u0b89\u0bb1\u0bb5\u0bc1<\/td>\n<td>Consistent, same at all times<\/td>\n<td>May change during warm-up<\/td>\n<\/tr>\n<tr>\n<td>Slow Roll Vibration<\/td>\n<td>Present (proportional to speed\u00b2)<\/td>\n<td>Present and often significant even at very low speed<\/td>\n<\/tr>\n<tr>\n<td>\u0b9a\u0bae\u0ba8\u0bbf\u0bb2\u0bc8\u0baa\u0bcd\u0baa\u0b9f\u0bc1\u0ba4\u0bcd\u0ba4\u0bb2\u0bc1\u0b95\u0bcd\u0b95\u0bbe\u0ba9 \u0baa\u0ba4\u0bbf\u0bb2\u0bb3\u0bbf\u0baa\u0bcd\u0baa\u0bc1<\/td>\n<td>Vibration reduced by correct balancing<\/td>\n<td>Minimal or no improvement; may get worse<\/td>\n<\/tr>\n<tr>\n<td>Thermal Sensitivity<\/td>\n<td>Relatively stable with temperature<\/td>\n<td>Changes significantly during warm-up\/cool-down<\/td>\n<\/tr>\n<tr>\n<td>Run-out Measurement<\/td>\n<td>Low when rotor at rest<\/td>\n<td>High run-out even at rest (permanent bow)<\/td>\n<\/tr>\n<\/table>\n<p>The single most telling row is the slow-roll line. Unbalance force collapses toward zero as speed drops because it scales with the square of rotational speed; a permanent bow, being a fixed geometric offset, still shows substantial run-out and 1\u00d7 motion at a crawl. That is the test that breaks the tie.<\/p>\n<h3>5.2 Diagnostic Tests<\/h3>\n<h4>5.2.1 Slow Roll Measurement<\/h4>\n<p>Rotate the shaft very slowly \u2014 typically 5\u201310% of operating speed \u2014 and measure <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/run-out\/\">run-out<\/a> with a <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/proximity-probe\/\">\uadfc\uc811 \ud0d0\uce68<\/a> or a dial indicator. High run-out at slow roll indicates shaft bow or mechanical run-out rather than unbalance, whose centrifugal force is negligible at such low speed. The slow-roll vector is also recorded so it can be subtracted from the running vibration data, isolating the true dynamic response from the static bow component.<\/p>\n<h4>5.2.2 Shut-Down Phase Shift<\/h4>\n<p>Monitor the vibration <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/phase-angle\/\">phase angle<\/a> as the machine coasts down. True unbalance holds a constant <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/phase\/\">phase<\/a> regardless of speed (away from resonance). A thermally bowed shaft tends to show phase that drifts as the rotor cools, and plotting amplitude and phase together on a <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/bode-plot\/\">Bode plot<\/a> \u0b85\u0bb2\u0bcd\u0bb2\u0ba4\u0bc1 <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/polar-plot\/\">polar plot<\/a> makes the difference far easier to read than raw numbers.<\/p>\n<h4>5.2.3 Thermal Bow Test<\/h4>\n<p>For a suspected thermal bow, monitor vibration through startup and warm-up. Thermal bow typically shows vibration <em>increasing<\/em> as the machine heats up, then stabilising or falling once thermal equilibrium is reached \u2014 the mirror image of a fault that grows purely with speed.<\/p>\n<h4>5.2.4 Off-Machine Run-Out Check<\/h4>\n<p>Remove the rotor, support it on V-blocks or between lathe centres, and rotate it slowly while measuring radial run-out with a dial indicator. Significant run-out \u2014 typically greater than 0.001 in (25 \u00b5m) \u2014 confirms a permanent bow. This bench check is the definitive proof, since a shaft that reads straight on the machine but bent on V-blocks tells a very different story from one that is bent in both.<\/p>\n<h4>5.2.5 Visual Inspection<\/h4>\n<p>On large shafts, sighting down the length of the shaft or using optical methods such as <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/laser-shaft-alignment\/\">laser alignment<\/a> equipment can reveal an obvious bow that the eye alone might miss.<\/p>\n<h2>6. \u0ba4\u0bbf\u0bb0\u0bc1\u0ba4\u0bcd\u0ba4 \u0bae\u0bc1\u0bb1\u0bc8\u0b95\u0bb3\u0bcd<\/h2>\n<p>The right correction depends on the bow&#8217;s severity and type. There is no single fix that suits every case.<\/p>\n<h3>6.1 For Permanent Mechanical Bow<\/h3>\n<h4>6.1.1 Shaft Straightening<\/h4>\n<p>For mild to moderate bow \u2014 typically below 0.005 in (125 \u00b5m) \u2014 the shaft can sometimes be cold- or hot-straightened with hydraulic presses. The shaft is supported and carefully over-bent so that it plastically deforms back toward straight, a process that demands specialised equipment, skilled technicians, and patience, since over-correcting simply creates a bow in the opposite direction.<\/p>\n<h4>6.1.2 Thermal Stress Relief<\/h4>\n<p>Heat-treating the shaft to relieve residual stresses can reduce or eliminate bow that originated from locked-in manufacturing or welding stress. This needs proper furnace equipment and tight process control to avoid introducing fresh distortion.<\/p>\n<h4>6.1.3 Shaft Replacement<\/h4>\n<p>For severe bow, or in critical service, replacement is often the most reliable answer. The cost of a new shaft has to be weighed against downtime and the real risk that a straightening attempt fails or relaxes back over time.<\/p>\n<h4>6.1.4 &#8220;Balancing Around the Bow&#8221;<\/h4>\n<p>In some cases \u2014 large turbines in particular \u2014 <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/correction-weight\/\">\u0ba4\u0bbf\u0bb0\u0bc1\u0ba4\u0bcd\u0ba4\u0bae\u0bcd \u0ba8\u0bbf\u0bb1\u0bc8\u0b95\u0bb3\u0bcd<\/a> can be calculated and fitted to counteract the <em>effect<\/em> of the bow at running speed. This does not straighten the shaft; it merely cancels the 1\u00d7 force the bow produces. It is a limited, generally temporary measure, and it leaves a rotor whose <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/residual-unbalance\/\">\u0bae\u0bc0\u0ba4\u0bae\u0bc1\u0bb3\u0bcd\u0bb3 \u0b8f\u0bb1\u0bcd\u0bb1\u0ba4\u0bcd\u0ba4\u0bbe\u0bb4\u0bcd\u0bb5\u0bc1<\/a> only looks acceptable at one specific speed and temperature.<\/p>\n<h3>6.2 For Thermal Bow<\/h3>\n<h4>6.2.1 Operating Procedure Changes<\/h4>\n<ul>\n<li>Implement slow, staged warm-up procedures.<\/li>\n<li>Maintain continuous turning-gear operation during shutdown to prevent thermal sag.<\/li>\n<li>Control steam admission or process-fluid temperatures more carefully.<\/li>\n<li>Ensure symmetric heating and cooling.<\/li>\n<\/ul>\n<h4>6.2.2 Design Modifications<\/h4>\n<ul>\n<li>Add insulation to reduce thermal gradients.<\/li>\n<li>Install heating jackets for uniform warm-up.<\/li>\n<li>Improve the cooling system to even out the temperature distribution.<\/li>\n<\/ul>\n<h4>6.2.3 Turning Gear Operation<\/h4>\n<p>For large turbines, running the turning gear (a slow-speed rotational drive) during warm-up and cool-down keeps the shaft turning so that heat is distributed evenly around the circumference, preventing the gradient that would otherwise bow the rotor.<\/p>\n<h2>7. Verifying the Rotor in the Field<\/h2>\n<p>Once a shaft has been straightened, replaced, or judged straight enough to run, the rotor still has to be checked dynamically in its own bearings \u2014 bench run-out alone does not prove it will run smoothly at speed. A portable two-channel analyser such as the <a href=\"https:\/\/vibromera.eu\/ta\/product\/balanset-1\/\">Balanset-1A<\/a> makes this practical on site: it captures the slow-roll vector, then measures 1\u00d7 <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/phase\/\">\u0bb5\u0bc0\u0b9a\u0bcd\u0b9a\u0bc1 \u0bae\u0bb1\u0bcd\u0bb1\u0bc1\u0bae\u0bcd \u0ba8\u0bbf\u0bb2\u0bc8<\/a> through the speed range so an engineer can separate any remaining bow component from genuine mass unbalance. Only once the slow-roll run-out confirms the shaft is acceptably straight does it make sense to proceed to a trim <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/balancing\/\">balance<\/a> \u2014 at which point the same instrument computes the <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/influence-coefficient\/\">\u0ba4\u0bbe\u0b95\u0bcd\u0b95 \u0b95\u0bc1\u0ba3\u0b95\u0b99\u0bcd\u0b95\u0bb3\u0bcd<\/a> and verifies the final result against an <a href=\"https:\/\/vibromera.eu\/ta\/glossary\/iso-21940-11\/\">ISO 21940-11<\/a> balance grade. You can pre-calculate that permissible residual figure with the <a href=\"https:\/\/vibromera.eu\/ta\/calculators\/residual-unbalance-iso1940\/\">\u0b8e\u0b9e\u0bcd\u0b9a\u0bbf\u0baf \u0b9a\u0bae\u0ba8\u0bbf\u0bb2\u0bc8\u0baf\u0bbf\u0ba9\u0bcd\u0bae\u0bc8 \u0b95\u0ba3\u0b95\u0bcd\u0b95\u0bc0\u0b9f\u0bcd\u0b9f\u0bbf (ISO 21940-11)<\/a> \u0ba8\u0bc0\u0b99\u0bcd\u0b95\u0bb3\u0bcd \u0ba4\u0bca\u0b9f\u0b99\u0bcd\u0b95\u0bc1\u0bb5\u0ba4\u0bb1\u0bcd\u0b95\u0bc1 \u0bae\u0bc1\u0ba9\u0bcd.<\/p>\n<h2>8. Prevention Strategies<\/h2>\n<p>Preventing shaft bow is far cheaper and faster than correcting it.<\/p>\n<h3>8.1 Design and Manufacturing<\/h3>\n<ul>\n<li>Use proper heat-treatment procedures to minimise residual stresses.<\/li>\n<li>Design adequate shaft stiffness for the application.<\/li>\n<li>Specify materials suited to the thermal environment.<\/li>\n<\/ul>\n<h3>8.2 Installation and Maintenance<\/h3>\n<ul>\n<li>Always lift rotors using designated lifting points, never by the shaft.<\/li>\n<li>Store spare rotors with proper support to prevent sag \u2014 ideally rotated periodically or supported near the journals.<\/li>\n<li>Avoid mechanical shock during handling.<\/li>\n<li>Check shaft straightness periodically (annually or per the manufacturer&#8217;s schedule).<\/li>\n<\/ul>\n<h3>8.3 Operation<\/h3>\n<ul>\n<li>Follow the manufacturer&#8217;s warm-up and shutdown procedures.<\/li>\n<li>Avoid rapid temperature changes.<\/li>\n<li>Monitor for signs of thermal bow during startups.<\/li>\n<li>Investigate any unexplained change in vibration phase promptly.<\/li>\n<\/ul>\n<h2>9. Impact on Balancing Procedures<\/h2>\n<p>Attempting to balance a bowed shaft is generally futile and can be actively counterproductive:<\/p>\n<ul>\n<li><strong>Ineffective corrections:<\/strong> weights calculated for mass unbalance cannot correct a geometric bow.<\/li>\n<li><strong>Masking the problem:<\/strong> partially &#8220;successful&#8221; balancing of a bowed shaft may cut vibration briefly while leaving the real defect \u2014 and its bearing loading \u2014 untouched.<\/li>\n<li><strong>Wasted time:<\/strong> repeated balancing runs that refuse to converge are themselves a red flag for bow.<\/li>\n<li><strong>Potential damage:<\/strong> piling large correction weights onto a bowed shaft raises stresses and can drive further damage or even fatigue cracking.<\/li>\n<\/ul>\n<p><strong>\u0b9a\u0bbf\u0bb1\u0ba8\u0bcd\u0ba4 \u0ba8\u0b9f\u0bc8\u0bae\u0bc1\u0bb1\u0bc8:<\/strong> always check for shaft bow before you begin balancing, especially if the rotor has any history of rough handling, thermal events, or vibration that no one has been able to explain. A two-minute slow-roll check can save a wasted afternoon and a damaged shaft.<\/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 shaft bow, a permanent or temporary curvature in a rotor shaft that causes vibration symptoms similar to unbalance but requires different diagnostic and correction approaches.<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[109,110],"tags":[],"class_list":["post-232","glossary","type-glossary","status-publish","hentry","category-glossary","category-vibration-diagnostics"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/ta\/wp-json\/wp\/v2\/glossary\/232","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":1,"href":"https:\/\/vibromera.eu\/ta\/wp-json\/wp\/v2\/glossary\/232\/revisions"}],"predecessor-version":[{"id":101458,"href":"https:\/\/vibromera.eu\/ta\/wp-json\/wp\/v2\/glossary\/232\/revisions\/101458"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/ta\/wp-json\/wp\/v2\/media?parent=232"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/ta\/wp-json\/wp\/v2\/categories?post=232"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/ta\/wp-json\/wp\/v2\/tags?post=232"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}