ANALISIS PENGARUH BENTUK PROFIL TERSUSUN TERHADAP GAYA TEKAN PADA BAJA CANAI DINGIN DENGAN METODE ELEMEN HINGGA

In this modern world of construction, the usage of cold formed steel has developed and started to widely used for main structures such as columns and beams. Cold formed steel is manufactured by folding a thin steel plate into desired model. This result in its relatively large width-to-thickness ratio. Therefore, the use of cold formed steel as a column to withstand compressive axial force is deemed ineffective because of its vulnerability to buckling failure. One of the ways to overcome buckling failure is to use built-up profile. The profiles in which are examined are R and 2R with the effective length of 2950mm and variated between fixed-fixed roller end and pinned-roller end. Whereas R profile is the combination of C and U channel. MIDAS FEA is a finite element-based software which is used to model the desired structures in this study. The results of the study showed calculations using MIDAS FEA are closer to the theoretical calculations of AISI S100-07 on the fixed-fixed roller end. The 2R profile provided 250% greater compressive strength value compared to the R profile. The fixed-fixed roller end resulted in 147% higher compressive strength compared to the pinned-roller end. The results using MIDAS FEA resulted in closer results to AISI S100-07.ABSTRAKPada dunia konstruksi modern penggunaan baja canai dingin sudah berkembang dan penggunaannya mulai banyak digunakan untuk struktur utama seperti kolom dan balok. Pembuatan baja canai dingin yang ditekuk dari pelat baja membuat ketebalannya relatif tipis jika dibandingkan dengan lebar ataupun tinggi nya. Akibatnya penggunaan baja canai dingin sebagai kolom yang dominan menahan gaya aksial tekan dirasa tidak efektif karena sifatnya yang rentan terhadap kegagalan tekuk. Salah satu cara untuk mengatasi kegagalan tekuk adalah menggunakan profil tersusun. Pada penelitian ini diuji adalah profil R dan 2R dengan panjang 2950 mm yang disertai dengan variasi peletakan sendi-rol dan jepit-jepit rol pada kedua ujungnya. Dimana profil R adalah profil gabungan antara profil C dan porfil U. Penelitian ini menggunakan program metode elemen hingga MIDAS FEA untuk memodelkan struktur yang diinginkan. Profil yang. Hasil analisis penelitian ini didapatkan bahwa perhitungan dengan program MIDAS FEA lebih mendekati perhitungan teoritis AISI S100-07 pada profil jepit-jepit rol. Untuk profil tersusun 2R memberikan kuat tekan lebih besar 250% dibandingkan dengan profil R. Peletakan jepit-jepit rol mengakibatkan kuat tekan baja canai dingin lebih tinggi 147% dibandingkan dengan peletakan sendi-rol. Pemodelan menggunakan MIDAS FEA memberikan hasil lebih mendekati perhitungan teoritis dengan AISI S100-07.

Basic study on effect of transport acceleration in electromagnetic levitation system for thin steel plate

Thin steel plates are widely used in various industrial products. However, because of the deterioration of surface quality and metal plating that occurs during transport, some problems exist. As a solution to these problems, a noncontact transport of steel plate using electromagnetic force has been proposed. However, side slip or the dropping of the plate may occur. Therefore, we proposed the addition of electromagnetic actuators to control the horizontal motion of levitated steel plates. In this study, we examined the change in the levitation stability during noncontact transport with the addition of positioning control in the horizontal direction or changed transport conditions. As a result, the application of a magnetic field in the horizontal direction improved the levitation stability of transported thin steel plates in different transport conditions.

Investigation of Laser Hardening Forming Method for Thin Steel Plate From a View of Origami Engineering

In recent years, products have been miniaturized and multi-functionalized, and the importance of integration in compact machine tools has increased. In this study, we propose integration via laser hardening forming which combines laser hardening and laser forming on a compact machine toolfor thin steel sheets. For the processing, the deformation and quenching were considered during repeated laser scanning repeated at the same location. In addition, to apply laser quenching forming to origami engineering, a test piece with resilience was prototyped. As a result, problems in repeated laser scanning were clarified, and the tool’s applicability to origami engineering was demonstrated.

Influence of Grooved Plate Cross-Sectional Shape on Bending Phenomena in Laser-Quenching Forming Process

This research proposes a method to achieve laser quenching and laser forming simultaneously. This technique uses a diode laser to produce thin steel sheet-assuming parts, such as springs and hinges. Energy and time are saved by combining the advantages of laser quenching, which has high input heat efficiency, and laser forming, which, unlike press molding, does not require metal molds. In this study, laser-quenching molding was performed for an entire thin steel plate, and the influence on warping was investigated. Furthermore, the proposed method was evaluated under repeated quenchings for different cross-sections of a workpiece. The results indicated that the technique prevented bending deformation during the next laser scan and reduced warping by increasing the second moment of area of the entire workpiece.