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Effects of manufacturing methods and production routes on residual stresses of rectangular and square hollow steel sections: a review

Abathun Mehari Zelalem, Han Jingtao, Yu Wang

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 3

246--264

EN

Rectangular and square hollow steel sections can be manufactured using either a “direct forming” or an “indirect forming” method. The production route for both “direct forming” and “indirect forming” techniques can be conducted at room temperature (cold forming) or elevated temperature (hot forming). It might also start by forming at room temperature and subsequently followed by heat treatment (hot-finishing). The manufacturing method and production route choice cause the final products that are roll-formed from the same material to possess different mechanical properties. One of the main reasons for the disparity of mechanical properties is the variation of residual stress induced during forming processes. In this paper, available numerical and experimental studies of different rectangular and square steel hollow sections manufacturing methods and production routes on residual stresses are comprehensively reviewed. Furthermore, studies on the effects of roll-forming parameters on product quality and residual stresses are integrated. Moreover, future research activities aiming to manufacture residual stresses-free rectangular and square hollow sections are recommended.

2

Material and technological issues in production of electrostatic precipitators collecting electrodes

Tracz P., Bacciarelli T., Wacławiak K., Kościelniak B.

Inżynieria Materiałowa

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2017

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Vol. 38, nr 4

198--204

EN

Collecting electrodes are the most important components of electrostatic precipitators. Producers of ash removing devices use formed profiles of Sigma type. This topology of electrodes combines the following basic features: high elasticity and rigidity resulting in efficient ash removal; fast dynamic reaction to hitting; limited release, erosion of the ash into the gas because of profile of the electrodes. Collecting electrodes are thin-walled, steel, open profiles. Technological process of electrode manufacturing involves multistage roll forming of steel strip 1.25÷1.5 mm thick, with calibration. Steel grades are chosen for manufacturing according to temperature of operation and composition of industrial gas. Temperature of operation ranges between 150÷300°C. Most producers use DC01 steel grade for collecting electrodes. However properties of DC01 steel grade are not efficient to PN-EN 10130 + A1 regarding cold working. Such criteria are met by grades of DC02 and DC03. In this article the vital structural and material features of steel strips for roll forming process were discussed. Furthermore, the optimization of roll forming process of collecting plate of Sigma type by using dedicated CAD software COPRA RF 2013 has been shown. Numerical simulations lead to comparison between archive data for 13 stages roll forming and current settings for 18-stage one and proved, that today’s setting of roll forming reduces displacements by about 70%.

PL

Porównano gatunki taśmy stalowej stosowanej do produkcji elektrod zbiorczych w elektrofiltrach suchych, scharakteryzowano proces technologiczny, wskazano tolerancje wykonania elektrod zbiorczych, porównano właściwości mechaniczne poszczególnych gatunków stali. Ponadto pokazano optymalizację procesu profilowania elektrody zbiorczej z zastosowaniem specjalistycznego oprogramowania.

3

Cold rolIed profiles for vehicle construction

Groche P., Henkelmann M., Gotz P., Berner S.

Archives of Civil and Mechanical Engineering

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2008

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Vol. 8, no 2

31-38

EN

So far car bodies are usually built as self-supporting structures. Recent studies show advantages using cold rolled sections in manufacturing car bodies, e. g. to reduce weight. The success of these components will for one thing be depending on technical feasibilities and for another thing on the profitability of the manufacturing processes. Promising approaches are presenled, which can help to increase the amounl or cold rolled sections in vehicle construclion.

PL

Karoserie samochodowe są zwykle budowane jako konstrukcje samonośne. Ostatnie badania wykazały duże korzyści wynikające z zastosowania walcowania na zimno kształtowników w produkcji karoserii samochodów, m. in. w celu zmniejszenia wagi. Sukces tych komponentów z jednej strony będzie zależał od technologicznej wykonalności a z drugiej strony od opłacalności procesu. W artykule zaprezentowano obiecujące podejścia, które mogą pomóc zwiększyć znaczenie zastosowanie walcowania na zimno kształtowników w konstrukcjach samochodowych.