طراحي، شبيه‌سازي و آناليز فرايند توليد برآمدگي لوله به‌روش شكل‌دهي انفجاري

DESIGN, SIMULATION AND ANALYSIS OF BULGE TUBE MANUFACTURING BY AN EXPLOSIVE FORMING PROCESS

اين تحقيق به‌منظور طراحي، آناليز و توليد بالج‌تيوب به‌روش شكل‌دهي انفجاري با واسطه‌ي آب انجام شد. همچنين اثر پارامترهاي فرايند بر روي كيفيت محصول مورد مطالعه قرار گرفت. بعد از انتخاب ماده‌ي منفجره و با استفاده از روش‌هاي عددي، داگلاس[1] و انرژي[2]، مقدار ماده‌ي منفجره‌ي مورد نياز براي تغيير شكل انفجاري محاسبه ‌شد. براي ساخت محصول مورد نظر به‌روش فيزيكي، يك سري قالب و چيدمان ماده‌ي منفجره طراحي شد. همچنين به‌منظور مدل سازي فرايند تغيير شكل انفجاري، از نرم‌افزارهاي AUTOCAD و HYPERMESH استفاده شد. سپس، براي شبيه سازي و آناليز فرايند انفجاري به‌روش اجزا محدود، از نرم‌افزار LS-DYNA استفاده ‌شد. سرانجام، اعتبار‌سنجي نتايج عددي به دست آمده، با استفاده از روش داگلاس و روش انرژي صورت گرفت.

Explosive forming is an alternative forming approach among metalworking processes, such as hydroforming, which can be applied in bulge forming to manufacture metal bulge tubes. Bulge forming is a manufacturing process that is important and desirable as a technology that can be used to make seamless, lightweight and near-net-shaped industrial components. Due to it’s capability of creating complex shapes in a single step, the process is being applied in the automotive and aerospace industries, where the demand for increased structural strength and decreased vehicle weight makes it a very attractive manufacturing method. The bulging process is an expansion of a part of a tube, in the radial direction, by mechanical or hydraulic means. The main benefit of bulging is to accommodate the movement of pipes, due to thermal and mechanical changes in the system. In this research work, the finite element simulation of the bulge forming process was carried out to demonstrate the design, analysis and manufacturing of a bulge tube by an underwater explosive forming process. In addition, the effects of process parameters on the quality of the product were studied. Then, the type of explosive material was selected and the quantity of material required for explosive forming was calculated using energy and Douglass??Douglas? methods. To make the workpart by physical explosive forming, a die-setup and a process were designed. Then, for modeling the explosive forming process, AUTO-CAD and HYPER-MESH were utilized. Simulation and analysis of the explosive process was undertaken using finite element software called LS-DYNA. Finally, the verification of numerical results was performed using energy and Douglass??Douglas? methods.