Modal Analysis of Double Beam Overhead Type Crane Systems by Finite Element Method

Abstract

Natural frequencies are a parameter determined by the mass and flexibility of the bodies. Since all the crane system elements are in contact with each other, they should be designed as a whole, and their frequencies should be determined. Therefore, the crane system is modelled as a whole system due to the presence of cars on the crane system and the movement of the structure with the load. In addition, modal analysis was performed by using finite element method in crane systems by taking into consideration the carrier frames in which the bridge group moves. In the crane system designed with bridge group, lifting group and load; analyses were made according to the fact that the car group and the load were at the beginning and middle of bridge. Natural frequency and mode shapes are obtained according to the specified conditions, comparisons have been made and the effects of the design characteristics on the results are emphasized.

Keywords

• Bridged crane,Finite element method,Modal analysis,Mechanical vibrations

ÇİFT KÖPRÜLÜ ASKI TİP KREN SİSTEMLERİNİN SONLU ELEMANLAR METODU İLE MODAL ANALİZİ

Abstract

Doğal frekanslar cisimlerin kütle ve esnekliğine bağlı olarak belirlenen bir parametredir.  Kren sistem elemanların hepsi birbiri ile temasta olmasından dolayı bir bütün olarak tasarlanıp frekansların belirlenmesi gerekmektedir. Bu nedenle kren sisteminin çalışma şartlarına göre üzerinde araba bulunması ve sistemde yapının yük ile hareket etmesi sebebi ile kren sistemi bir bütün olarak modellenmiştir. Ayrıca kren sistemlerinde köprü grubunun hareket ettiği taşıyıcı çerçevelerde dikkate alınarak modal analizler Sonlu Elamanlar Metodu (SEM) ile yapılmıştır. Köprü grubu, kaldırma grubu ve yük ile tasarlanan kren sisteminde; araba grubunun ve yükün köprü başında ve ortasında olması durumlarına göre de analizler yapılmıştır. Belirtilen şartlara göre doğal frekans ve mod şekilleri elde edilerek, karşılaştırmalar yapılmış ve tasarım özelliklerinin sonuçlar üzerindeki etkileri üzerinde durulmuştur.

Keywords

• Köprülü kren,Sonlu elemanlar metodu,Modal analiz,Mekanik Titreşimler

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