{"id":230,"date":"2025-10-31T00:25:51","date_gmt":"2025-10-31T00:25:51","guid":{"rendered":"https:\/\/vibromera.eu\/glossary\/self-excited-vibration\/"},"modified":"2026-05-23T22:39:08","modified_gmt":"2026-05-23T22:39:08","slug":"self-excited-vibration","status":"publish","type":"glossary","link":"https:\/\/vibromera.eu\/ro\/glossary\/self-excited-vibration\/","title":{"rendered":"Ce este vibra\u021bia autoexcitat\u0103? \u2013 R\u0103spunsuri instabile ale sistemului"},"content":{"rendered":"<h1>\u00cen\u021belegerea vibra\u021biei autoexcitate<\/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\/ro\/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\/ro\/product\/balanset-1\/\" title=\"Echilibrator portabil \u0219i analizor de vibra\u021bii 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 kit complet \u2014 echilibrator portabil \u0219i analizor de vibra\u021bii\" 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\/ro\/product-category\/devices\/\" rel=\"tag\">Dispozitive<\/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\/ro\/product\/balanset-1\/\" title=\"Echilibrator portabil \u0219i analizor de vibra\u021bii Balanset-1A\">Echilibrator portabil \u0219i analizor de vibra\u021bii 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> + TVA (dac\u0103 este cazul)<\/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=\"\/ro\/wp-json\/wp\/v2\/glossary\/230?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=\"Adaug\u0103 \u00een co\u0219\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Adaug\u0103 \u00een co\u0219\" 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=\"\/ro\/wp-json\/wp\/v2\/glossary\/230?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=\"Adaug\u0103 \u00een co\u0219: &amp;lbquo;Portable balancer &amp; Vibration analyzer Balanset-1A\u201d\" rel=\"nofollow\" data-success_message=\"\u201ePortable balancer &amp; Vibration analyzer Balanset-1A\u201d a fost ad\u0103ugat \u00een co\u0219\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Adaug\u0103 \u00een co\u0219<\/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\/ro\/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\/ro\/product\/vibration-sensor\/\" title=\"Senzor de vibra\u021bii\">\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=\"Prim-plan senzor de vibra\u021bii Balanset-1A\" 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\/ro\/product-category\/parts\/\" rel=\"tag\">Piese<\/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\/ro\/product\/vibration-sensor\/\" title=\"Senzor de vibra\u021bii\">Senzor de vibra\u021bii<\/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> + TVA (dac\u0103 este cazul)<\/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=\"\/ro\/wp-json\/wp\/v2\/glossary\/230?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=\"Adaug\u0103 \u00een co\u0219\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Adaug\u0103 \u00een co\u0219\" 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=\"\/ro\/wp-json\/wp\/v2\/glossary\/230?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=\"Adaug\u0103 \u00een co\u0219: &amp;lbquo;Vibration sensor\u201d\" rel=\"nofollow\" data-success_message=\"\u201eVibration sensor\u201d a fost ad\u0103ugat \u00een co\u0219\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Adaug\u0103 \u00een co\u0219<\/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\/ro\/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\/ro\/product\/optical-sensor-for-balanset-and-arbalance\/\" title=\"Senzor optic (tahometru cu laser)\">\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=\"Senzor optic (tahometru cu laser)\" 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\/ro\/product-category\/parts\/\" rel=\"tag\">Piese<\/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\/ro\/product\/optical-sensor-for-balanset-and-arbalance\/\" title=\"Senzor optic (tahometru cu laser)\">Senzor optic (tahometru cu laser)<\/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> + TVA (dac\u0103 este cazul)<\/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=\"\/ro\/wp-json\/wp\/v2\/glossary\/230?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=\"Adaug\u0103 \u00een co\u0219\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Adaug\u0103 \u00een co\u0219\" 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=\"\/ro\/wp-json\/wp\/v2\/glossary\/230?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=\"Adaug\u0103 \u00een co\u0219: &amp;lbquo;Optical Sensor (Laser Tachometer)\u201d\" rel=\"nofollow\" data-success_message=\"\u201eOptical Sensor (Laser Tachometer)\u201d a fost ad\u0103ugat \u00een co\u0219\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Adaug\u0103 \u00een co\u0219<\/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\/ro\/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\/ro\/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=\"Kit de echilibrare a rotorului Vibromera: geant\u0103 de transport, condi\u021bioner de semnal multicanal, analizor portabil, baz\u0103 magnetic\u0103, senzori de vibra\u021bii \u0219i cabluri spiralate.\" 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\/ro\/product-category\/devices\/\" rel=\"tag\">Dispozitive<\/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\/ro\/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> + TVA (dac\u0103 este cazul)<\/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=\"\/ro\/wp-json\/wp\/v2\/glossary\/230?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=\"Adaug\u0103 \u00een co\u0219\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Adaug\u0103 \u00een co\u0219\" 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=\"\/ro\/wp-json\/wp\/v2\/glossary\/230?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=\"Adaug\u0103 \u00een co\u0219: &amp;lbquo;Balanset-4\u201d\" rel=\"nofollow\" data-success_message=\"\u201eBalanset-4\u201d a fost ad\u0103ugat \u00een co\u0219\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Adaug\u0103 \u00een co\u0219<\/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\/ro\/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\/ro\/product\/magnet-stand\/\" title=\"Stand magnetic 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=\"Baza magnetic\u0103.\" srcset=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36-230x153.webp 230w, 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class=\"shop-item-title-link\" href=\"https:\/\/vibromera.eu\/ro\/product\/magnet-stand\/\" title=\"Stand magnetic Insize-60-kgf\">Stand magnetic 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> + TVA (dac\u0103 este cazul)<\/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=\"\/ro\/wp-json\/wp\/v2\/glossary\/230?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=\"Adaug\u0103 \u00een co\u0219\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Adaug\u0103 \u00een co\u0219\" class=\"fas fa-cart-plus\" 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shop-item\">\n\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/ro\/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\/ro\/product\/reflective-tape\/\" title=\"Band\u0103 reflectorizant\u0103\">\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=\"Band\u0103 reflectorizant\u0103\" 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, 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cazul)<\/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=\"\/ro\/wp-json\/wp\/v2\/glossary\/230?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=\"Adaug\u0103 \u00een co\u0219\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Adaug\u0103 \u00een co\u0219\" 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=\"\/ro\/wp-json\/wp\/v2\/glossary\/230?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=\"Adaug\u0103 \u00een co\u0219: &amp;lbquo;Reflective tape\u201d\" rel=\"nofollow\" data-success_message=\"\u201eReflective tape\u201d a fost ad\u0103ugat \u00een co\u0219\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Adaug\u0103 \u00een co\u0219<\/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\/ro\/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\/ro\/product\/dynamic-balancer-balanset-1a\/\" title=\"Echilibrator dinamic &quot;Balanset-1A&quot; 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=\"Con\u021binutul kitului Balanset-1A cu unitate de interfa\u021b\u0103, senzori, tahometru \u0219i accesorii\" 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\/ro\/product-category\/devices\/\" rel=\"tag\">Dispozitive<\/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\/ro\/product\/dynamic-balancer-balanset-1a\/\" title=\"Echilibrator dinamic &quot;Balanset-1A&quot; OEM\">Echilibrator dinamic \"Balanset-1A\" 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> + TVA (dac\u0103 este cazul)<\/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=\"\/ro\/wp-json\/wp\/v2\/glossary\/230?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=\"Adaug\u0103 \u00een co\u0219\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Adaug\u0103 \u00een co\u0219\" 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=\"\/ro\/wp-json\/wp\/v2\/glossary\/230?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=\"Adaug\u0103 \u00een co\u0219: &amp;lbquo;Dynamic balancer \u201cBalanset-1A\u201d OEM\u201d\" rel=\"nofollow\" data-success_message=\"\u201eDynamic balancer \u201cBalanset-1A\u201d OEM\u201d a fost ad\u0103ugat \u00een co\u0219\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Adaug\u0103 \u00een co\u0219<\/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>Vibra\u021bie autoexcitat\u0103<\/strong> \u2014 denumit\u0103 \u0219i vibra\u021bie autoindus\u0103 sau instabil\u0103 \u2014 este o categorie de mi\u0219care deosebit de periculoas\u0103, \u00een care mi\u0219carea unui sistem genereaz\u0103 chiar for\u021bele care sus\u021bin sau amplific\u0103 acea mi\u0219care. Rezultatul este o bucl\u0103 de reac\u021bie \u00eenchis\u0103: vibra\u021bia \u00ee\u0219i creeaz\u0103 propria for\u021b\u0103 motrice, astfel \u00eenc\u00e2t amplitudinea poate cre\u0219te, uneori p\u00e2n\u0103 la un nivel catastrofal, f\u0103r\u0103 ca excita\u021bia extern\u0103 s\u0103 creasc\u0103 \u00een vreun fel. Acesta este mecanismul care st\u0103 la baza unora dintre cele mai temute instabilit\u0103\u021bi din <a href=\"https:\/\/vibromera.eu\/ro\/glossary\/rotor-dynamics\/\">dinamica rotorului<\/a>, iar recunoa\u0219terea rapid\u0103 a acesteia reprezint\u0103 o abilitate diagnostic\u0103 esen\u021bial\u0103.<\/p>\n<p>Acest lucru este fundamental diferit de un <a href=\"https:\/\/vibromera.eu\/ro\/glossary\/forced-vibration\/\">vibra\u021bie for\u021bat\u0103<\/a> cum ar fi <a href=\"https:\/\/vibromera.eu\/ro\/glossary\/unbalance\/\">dezechilibru<\/a> sau <a href=\"https:\/\/vibromera.eu\/ro\/glossary\/misalignment\/\">nealiniere<\/a>, unde vibra\u021bia reprezint\u0103 o reac\u021bie direct\u0103 \u0219i propor\u021bional\u0103 la un impuls periodic specific, la o frecven\u021b\u0103 de excita\u021bie cunoscut\u0103. Dac\u0103 se dubleaz\u0103 dezechilibrul, se dubleaz\u0103 \u0219i reac\u021bia; dac\u0103 se elimin\u0103 impulsul, vibra\u021bia \u00eenceteaz\u0103. \u00centr-un sistem autoexcitat nu exist\u0103 un astfel de impuls extern \u2014 mi\u0219carea se autoalimenteaz\u0103, iar energia care o antreneaz\u0103 provine dintr-o surs\u0103 constant\u0103, cum ar fi rota\u021bia, curgerea unui fluid sau un proces de t\u0103iere.<\/p>\n<h2>1. Mecanismul buclei de feedback<\/h2>\n<p>Mecanismul unei vibra\u021bii autoexcitate poate fi prezentat sub forma unei secven\u021be:<\/p>\n<ol>\n<li>Un sistem \u2014 s\u0103 zicem un rotor care se rote\u0219te \u00een lag\u0103rul s\u0103u \u2014 se afl\u0103 \u00een mi\u0219care uniform\u0103.<\/li>\n<li>O mic\u0103 perturbare aleatorie produce o u\u0219oar\u0103 deplasare sau o u\u0219oar\u0103 modificare a vitezei.<\/li>\n<li>Aceast\u0103 schimbare de mi\u0219care modific\u0103 for\u021bele care ac\u021bioneaz\u0103 asupra sistemului \u2014 de exemplu, presiunea fluidului \u00eentr-un <a href=\"https:\/\/vibromera.eu\/ro\/glossary\/journal-bearing\/\">lag\u0103r cu alunecare<\/a> sau for\u021ba de t\u0103iere exercitat\u0103 asupra unei scule.<\/li>\n<li>\u00cen mod esen\u021bial, for\u021ba modificat\u0103 ac\u021bioneaz\u0103 astfel \u00eenc\u00e2t s\u0103 <em>adauge energie<\/em> \u00een sistem, \u00eemping\u00e2nd componenta \u0219i mai mult \u00een direc\u021bia \u00een care se deplasa deja.<\/li>\n<li>Mi\u0219carea intensificat\u0103 genereaz\u0103 o for\u021b\u0103 \u0219i mai mare, care adaug\u0103 \u0219i mai mult\u0103 energie \u2014 iar ciclul se repet\u0103.<\/li>\n<\/ol>\n<p>Bucla determin\u0103 cre\u0219terea amplitudinii p\u00e2n\u0103 c\u00e2nd aceasta este limitat\u0103 de neliniarit\u0103\u021bile sistemului (rotorul lovind un opritor rigid, o garnitur\u0103 care \u00eenchide un spa\u021biu liber) sau p\u00e2n\u0103 c\u00e2nd apare o defec\u021biune. Principiul fizic fundamental \u021bine de echilibrul energetic: apare o instabilitate ori de c\u00e2te ori for\u021ba dependent\u0103 de mi\u0219care alimenteaz\u0103 sistemul cu energie mai repede dec\u00e2t capacitatea acestuia de a o <a href=\"https:\/\/vibromera.eu\/ro\/glossary\/damping\/\">amortizare<\/a> o poate disipa. Prin urmare, o amortizare adecvat\u0103 reprezint\u0103 prima linie de ap\u0103rare \u00eempotriva autoexcita\u021biei.<\/p>\n<h2>2. Exemple frecvente de vibra\u021bii autoexcitate<\/h2>\n<p>Mai multe fenomene binecunoscute din domeniul diagnostic\u0103rii utilajelor reprezint\u0103 exemple clasice de vibra\u021bii autoexcitate:<\/p>\n<ul>\n<li><strong><a href=\"https:\/\/vibromera.eu\/ro\/glossary\/oil-whirl\/\">V\u00e2rtej de ulei<\/a> \u0219i biciuire de ulei (oil whip):<\/strong> cele mai frecvente exemple \u00een cazul ma\u0219inilor rotative. \u00centr-un lag\u0103r cu film de fluid, arborele rotativ antreneaz\u0103 uleiul \u00eentr-o zon\u0103 de \u00eenc\u0103rcare. O perturbare poate determina aceast\u0103 zon\u0103 s\u0103 se roteasc\u0103 (s\u0103 se \u00eenv\u00e2rt\u0103) \u00een jurul lag\u0103rului; presiunea exercitat\u0103 de aceast\u0103 zon\u0103 rotitoare \u00eempinge arborele, ad\u0103ug\u00e2nd \u0219i mai mult\u0103 energie mi\u0219c\u0103rii de rota\u021bie. Vibra\u021bia rezultat\u0103 nu are loc la viteza de func\u021bionare, ci la o <a href=\"https:\/\/vibromera.eu\/ro\/glossary\/sub-synchronous\/\">subsincron<\/a> frecven\u021b\u0103, de obicei 0,42\u20130,48&times; <a href=\"https:\/\/vibromera.eu\/ro\/glossary\/running-speed\/\">vitez\u0103 de func\u021bionare<\/a>. Dac\u0103 frecven\u021ba v\u00e2rtejului cre\u0219te p\u00e2n\u0103 c\u00e2nd coincide cu cea a rotorului <a href=\"https:\/\/vibromera.eu\/ro\/glossary\/natural-frequency\/\">frecven\u021b\u0103 natural\u0103<\/a>, se intensific\u0103 \u0219i degenereaz\u0103 \u00eentr-o form\u0103 mult mai violent\u0103 <a href=\"https:\/\/vibromera.eu\/ro\/glossary\/shaft-whip\/\">precesie<\/a> stare.<\/li>\n<li><strong>Trepida\u021bii (chatter) la prelucrare:<\/strong> La strunjire sau frezare, vibra\u021biile apar atunci c\u00e2nd scula de t\u0103iere \u00eencepe s\u0103 vibreze. Aceast\u0103 vibra\u021bie determin\u0103 varia\u021bii ale grosimii a\u0219chiei, iar grosimea variabil\u0103 a a\u0219chiei face ca for\u021ba de t\u0103iere s\u0103 fluctueze; la r\u00e2ndul s\u0103u, for\u021ba fluctuant\u0103 alimenteaz\u0103 din nou vibra\u021bia sculei cu energie \u2014 transform\u00e2nd-o \u00eentr-o vibra\u021bie violent\u0103, care se autoalimenteaz\u0103 \u0219i care distruge finisajul suprafe\u021bei \u0219i scula.<\/li>\n<li><strong>Flutter aerodinamic:<\/strong> vibra\u021bia combinat\u0103 de \u00eencovoiere \u0219i r\u0103sucire a unei aripi de avion (sau a unei pale de turbin\u0103), \u00een care mi\u0219carea modific\u0103 profilul aerodinamic, profilul modificat altereaz\u0103 presiunea aerului, iar presiunea modificat\u0103 realimenteaz\u0103 mi\u0219carea cu energie \u2014 ceea ce duce la o defec\u021biune catastrofal\u0103 dac\u0103 nu este controlat\u0103.<\/li>\n<li><strong><a href=\"https:\/\/vibromera.eu\/ro\/glossary\/rotor-rub\/\">Rotorul se freac\u0103<\/a>:<\/strong> atunci c\u00e2nd un rotor intr\u0103 \u00een contact cu o pies\u0103 fix\u0103, frecarea la punctul de contact \u00eenc\u0103lze\u0219te rotorul la nivel local \u0219i \u00eel deformeaz\u0103. Deformarea spore\u0219te for\u021ba de frecare, ceea ce intensific\u0103 c\u0103ldura \u0219i deformarea, cre\u00e2nd un cerc vicios termic care poate duce la blocarea motorului.<\/li>\n<\/ul>\n<p>Al\u021bi doi veri\u0219ori ac\u021biona\u021bi hidraulic, pe care merit\u0103 s\u0103-i cunoa\u0219te\u021bi, sunt <a href=\"https:\/\/vibromera.eu\/ro\/glossary\/steam-whirl\/\">v\u00e2rtej de abur<\/a> \u00een turbine \u0219i \u00een familia mai larg\u0103 a instabilit\u0103\u021bilor induse de curgere, determinate de <a href=\"https:\/\/vibromera.eu\/ro\/glossary\/aerodynamic-forces\/\">for\u021be aerodinamice<\/a>, ambele respect\u00e2nd aceea\u0219i logic\u0103 a retroaliment\u0103rii energetice.<\/p>\n<h2>3. Vibra\u021bia autoindus\u0103 vs. vibra\u021bia for\u021bat\u0103: o privire de ansamblu<\/h2>\n<table border=\"1\" style=\"width:100%; border-collapse:collapse;\">\n<tr>\n<th>Tr\u0103s\u0103tur\u0103<\/th>\n<th>Vibra\u021bii for\u021bate<\/th>\n<th>Vibra\u021bie autoexcitat\u0103<\/th>\n<\/tr>\n<tr>\n<td>Frecven\u021ba de conducere<\/td>\n<td>Se seteaz\u0103 printr-o intrare extern\u0103 (de ex. 1&times; pentru dezechilibru)<\/td>\n<td>Stabilit\u0103 de sistemul \u00eensu\u0219i, adesea o frecven\u021b\u0103 natural\u0103<\/td>\n<\/tr>\n<tr>\n<td>Frecven\u021ba vs. viteza<\/td>\n<td>Urm\u0103re\u0219te tura\u021bia de func\u021bionare<\/td>\n<td>Adesea sub-sincron \u0219i nu se sincronizeaz\u0103 cu 1&times;<\/td>\n<\/tr>\n<tr>\n<td>Comportamentul amplitudinii<\/td>\n<td>Stabil, propor\u021bional cu for\u021ba<\/td>\n<td>Poate cre\u0219te f\u0103r\u0103 limite p\u00e2n\u0103 c\u00e2nd intervine o neliniaritate<\/td>\n<\/tr>\n<tr>\n<td>Sursa de energie<\/td>\n<td>For\u021ba extern\u0103 periodic\u0103<\/td>\n<td>O surs\u0103 constant\u0103 (rota\u021bie, curgere, t\u0103iere) exploatat\u0103 de mi\u0219care<\/td>\n<\/tr>\n<\/table>\n<h2>4. Caracteristici cheie \u0219i diagnostic<\/h2>\n<p>Vibra\u021biile autoexcitate tind s\u0103 lase urme caracteristice \u00een <a href=\"https:\/\/vibromera.eu\/ro\/glossary\/spectrum\/\">Spectrul FFT<\/a>:<\/p>\n<ul>\n<li><strong>Frecven\u021be nesincronizate:<\/strong> Vibra\u021bia nu este, de obicei, un multiplu \u00eentreg sau o armonic\u0103 a vitezei de func\u021bionare. De obicei, aceasta se situeaz\u0103 la o frecven\u021b\u0103 subsincron\u0103.<\/li>\n<li><strong>Instabilitate:<\/strong> amplitudinea poate fi extrem de neregulat\u0103 \u0219i poate cre\u0219te brusc la cele mai mici varia\u021bii de vitez\u0103, temperatur\u0103 sau sarcin\u0103.<\/li>\n<li><strong>Apari\u021bie brusc\u0103:<\/strong> vibra\u021bia poate s\u0103 nu se simt\u0103 deloc p\u00e2n\u0103 c\u00e2nd utilajul nu dep\u0103\u0219e\u0219te o anumit\u0103 vitez\u0103 sau un anumit prag de sarcin\u0103 \u2014 adesea legat de un <a href=\"https:\/\/vibromera.eu\/ro\/glossary\/critical-speed\/\">vitez\u0103 critic\u0103<\/a> \u2014 moment \u00een care apare brusc \u0219i cu o amplitudine mare.<\/li>\n<\/ul>\n<p>Diagnosticul presupune identificarea acelor v\u00e2rfuri caracteristice nesincronizate \u0219i apoi deducerea mecanismului fizic care ar putea genera o astfel de instabilitate \u00een ma\u0219ina respectiv\u0103. Deoarece apari\u021bia fenomenului este legat\u0103 de condi\u021biile de func\u021bionare, o \u00eenregistrare a varia\u021biei de tura\u021bie este deosebit de revelatoare: o <a href=\"https:\/\/vibromera.eu\/ro\/glossary\/cascade-plot\/\">diagram\u0103 \u00een cascad\u0103<\/a> \u00eenregistrat\u0103 \u00een timpul acceler\u0103rii sau deceler\u0103rii arat\u0103 apari\u021bia unei componente subsincrone, care se stabilizeaz\u0103 apoi pe o frecven\u021b\u0103 natural\u0103, ceea ce constituie semnul distinctiv al trecerii de la rota\u021bie \u00een v\u00e2rtej la rota\u021bie \u00een bici. \u00cen cazurile legate de rulmen\u021bi, o <a href=\"https:\/\/vibromera.eu\/ro\/calculators\/journal-bearing-frequencies\/\">Calculator al frecven\u021bei defectelor la lag\u0103rele cu alunecare<\/a> ajut\u0103 la confirmarea faptului c\u0103 un v\u00e2rf suspect se \u00eencadreaz\u0103 \u00een banda de v\u00e2rtej al uleiului. Termenul general pentru acest \u00eentreg comportament este <a href=\"https:\/\/vibromera.eu\/ro\/glossary\/rotor-instability\/\">instabilitatea rotorului<\/a>, iar diferen\u021bierea acesteia de o reac\u021bie for\u021bat\u0103 reprezint\u0103 primul \u0219i cel mai important punct de decizie pentru analist \u2014 deoarece solu\u021bia este complet diferit\u0103: vibra\u021biile for\u021bate se reduc prin echilibrare sau aliniere, \u00een timp ce o instabilitate auto-excitat\u0103 trebuie eliminat\u0103 prin modificarea geometriei rulmentului, a jocului, a sarcinii sau a amortiz\u0103rii.<\/p>\n<h2>5. De ce nu poate fi eliminat prin echilibrare<\/h2>\n<p>Din fizic\u0103 decurge direct o avertizare practic\u0103. Deoarece o vibra\u021bie auto-excitat\u0103 nu reprezint\u0103 o reac\u021bie la un punct de greutate rotativ, aceasta nu poate fi remediat\u0103 prin ad\u0103ugarea de greut\u0103\u021bi de compensare \u2014 energia este furnizat\u0103 de fluidul din rulment, de procesul de t\u0103iere sau de fluxul de aer, nu de un dezechilibru de mas\u0103. Tocmai de aceea este important\u0103 efectuarea unei m\u0103sur\u0103tori atente la fa\u021ba locului \u00eenainte de orice interven\u021bie de remediere: atunci c\u00e2nd un inginer \u00eenregistreaz\u0103 amplitudinea \u0219i faza cu ajutorul unui analizor portabil cu dou\u0103 canale, precum <a href=\"https:\/\/vibromera.eu\/ro\/produs\/balanset-1\/\">Balanset-1A<\/a>, un vector 1&times; stabil \u0219i repetabil indic\u0103 o problem\u0103 real\u0103 de echilibrare, \u00een timp ce o component\u0103 instabil\u0103, sub-sincron\u0103 \u0219i nerepetabil\u0103 reprezint\u0103 un semnal de alarm\u0103 care arat\u0103 c\u0103 defec\u021biunea este o instabilitate \u0219i c\u0103 echilibrarea ar fi un efort inutil. Citirea <a href=\"https:\/\/vibromera.eu\/ro\/glossary\/vibration-analyzer\/\">analizor<\/a> astfel, se evit\u0103 gre\u0219eala clasic\u0103 de a \u00eencerca s\u0103 se compenseze un <a href=\"https:\/\/vibromera.eu\/ro\/glossary\/whirl\/\">v\u00e2rtej<\/a>.<\/p>\n<hr>\n<p><a href=\"https:\/\/vibromera.eu\/ro\/glossary\/\">\u2190 \u00cenapoi la indexul principal<\/a><\/p>","protected":false},"excerpt":{"rendered":"<p>O explica\u021bie a vibra\u021biei autoexcitate, un tip periculos de vibra\u021bie \u00een care mi\u0219carea \u00een sine creeaz\u0103 for\u021bele care sus\u021bin sau amplific\u0103 vibra\u021bia, cum ar fi v\u00e2rtejul \u0219i vibra\u021biile uleiului.<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[109,110],"tags":[],"class_list":["post-230","glossary","type-glossary","status-publish","hentry","category-glossary","category-vibration-diagnostics"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/ro\/wp-json\/wp\/v2\/glossary\/230","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vibromera.eu\/ro\/wp-json\/wp\/v2\/glossary"}],"about":[{"href":"https:\/\/vibromera.eu\/ro\/wp-json\/wp\/v2\/types\/glossary"}],"version-history":[{"count":1,"href":"https:\/\/vibromera.eu\/ro\/wp-json\/wp\/v2\/glossary\/230\/revisions"}],"predecessor-version":[{"id":101308,"href":"https:\/\/vibromera.eu\/ro\/wp-json\/wp\/v2\/glossary\/230\/revisions\/101308"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/ro\/wp-json\/wp\/v2\/media?parent=230"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/ro\/wp-json\/wp\/v2\/categories?post=230"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/ro\/wp-json\/wp\/v2\/tags?post=230"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}