مهندسی مکانیک مدرس

مهندسی مکانیک مدرس

بررسی پارامترهای اثرگذار بر طول تغییرشکل در فرایند شکل دهی غلتکی انعطاف ‌پذیر

نوع مقاله : پژوهشی اصیل

نویسندگان
1 دانشگاه تربیت مدرس، تهران
2 دانشگاه آزاد اسلامی واحد قزوین، قزوین
3 دانشگاه فنی و حرفه ای استان تهران
چکیده
در این مقاله با استفاده از شبیه‏ سازی اجزای محدود و نتایج آزمایش‏ های تجربی، تغییرات طول تغییرشکل و کرنش طولی در شکل‏ دهی غلتکی انعطاف‏ پذیر مورد بررسی قرار می ‏گیرد و ارتباط بین آن‏ها مشخص می‏ گردد. شکل ‏دهی غلتکی انعطاف پذیر، یک فرایند ساخت نوین برای تولید پروفیل‏ های با سطح مقطع متغیر است. یکی از پارامتر‏های مهم این فرایند، فاصله نقطه‏ ی شروع تغییرشکل پیش از ایستگاه شکل‏ دهی تا مقطع مرکزی غلتک ­ها در آن ایستگاه است که به آن طول تغییرشکل گفته می ‏شود. این پارامتر در تعیین فاصله بین ایستگا‏ه­ های شکل­ دهی و رفتار تغییرشکل ورق نقش اساسی دارد. همچنین اثر قطر غلتک و خواص مکانیکی ورق بر طول تغییرشکل مشخص می‏ گردد. نتایج نشان داد بیشینه طول تغییرشکل به هنگام شکل‏ دهی بخش کششی پروفیل کانالی با سطح مقطع متغیر روی می‏ دهد که علت آن کشش مضاعفی است که به علت هندسه مقعر بال در این بخش به لبه آن اعمال می ‏شود. همچنین نتایج نشان داد که با افزایش قطر غلتک و تنش تسلیم، طول تغییرشکل در هر چهار بخش باریک، کششی، فشاری و عریض پروفیل کانالی با سطح مقطع متغیر افرایش می­ یابد در حالی که با افزایش ضخامت ورق، طول تغییرشکل در این بخش‏ها کاهش می یابد.
کلیدواژه‌ها

موضوعات


عنوان مقاله English

Investigation of parameters affecting deformation length in flexible roll forming process

نویسندگان English

hassan badparva 1
Hassan Moslemi Naeini 1
Mohammmad Mehdi Kasaei 2
Yaghob Dadgar Asl 3
Behnam Abbaszadeh 1
1 Tarbiat Modares University, Tehran, IR Iran
2 Department of Mechanical Engineering, Qazvin Branch, Islamic Azad University, Qazvin, IR Iran
3 Department of mechanical engineering , Tehran Branch , Faculty of Enghelab-e Eslami, Technical and vocational university , Tehran , IR Iran
چکیده English

In this paper, using finite element simulations and experimental results, the changes in deformation length and longitudinal strain in flexible roll forming are investigated and the relationship between them is determined. Flexible roll forming is a novel manufacturing process for producing profiles with variable cross-section. One of the important parameters of this process is the distance from the starting point of the deformation before the forming station to the central cross-section of the rolls at that station, which is called the deformation length. This parameter plays a key role in determining the distance between the forming stations and the deformation behavior of the sheet. The effect of roll diameter and mechanical properties of the sheet on the deformation length is also determined. The results showed that the maximum deformation length occurs when forming the stretching zone of the channel profile with variable cross-section, which is due to the additional tension applied to the edge due to the concave geometry of the flange in this zone. The results also showed that with increasing roll diameter and yield stress, the deformation length in all four of the stretching and compression zones and the slim and wide areas of the channel profile with variable cross-section increases, while with increasing sheet thickness, the deformation length in these zones decreases.

کلیدواژه‌ها English

Variable cross-section profile
Deformation length
Longitudinal strain
Roll diameter
Sheet mechanical properties
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