Papers by Keyword: Cold Roll Forming

Abstract: In recent years, the movement that banning the sale of gasoline cars and diesel vehiclesespecially in Europe and allowing only electric cars for passenger’s cars has been accelerated. Forexamples, Germany’s federal council, the Bundesrat, has passed a resolution calling for a ban oncombustion engine cars by 2030. If the ban were to go through, German citizens would only bepermitted to purchase electric or hydrogen-fueled cars. In Norway, until 2025 there is a movement tolegislation prohibiting the registration of new cars for passenger car gasoline and diesel cars.Beginning in 2025 in the Netherlands, a bill to prohibit the sale of new cars for gasoline and dieselvehicles was submitted to Congress. Under the circumstances, the growing demand for light weightproducts for automotive industries has been increased due to global trend of environmentalpreservation. Although requires of magnesium has risen dramatically, production of magnesium alloysheet remains still at a very low level in practical use. The aim of the study is to establish a guidelinefor roll design in the roll forming of wrought magnesium alloys to extend practical use of roll formedproducts of wrought magnesium alloys. A three-dimensional elasto-plastic analysis by finite elementmethod has been conducted to express exact roll forming behavior of wrought magnesium alloys thathave different stress-strain curves in tension and compression. A simple V-sections were formed by atandem six stands roll forming machine to demonstrate effectiveness of the simulation methods withdifferent stress-strain curves in the case of tension and compression. Also, spring back analysis hasbeen performed to investigate exact cold roll forming phenomenon for wrought magnesium alloysheets.

Abstract: With the steady increase in demand for roll formed products, due to their application in fields such as automotive, construction, architecture, etc., roll forming companies are challenged with rising customer demands. Companies are struggling to bring a product through from design to manufacture at improved rates, whilst achieving tighter tolerances. The roll forming process may also induce undesirable forming defects such as twist, distortion and straightness problems. Over the years, numerical simulations have been deployed to assist with the geometric validation of these effects. For the purpose of this paper, an investigation shall focus on an individual parameter within the finite element analysis of the cold roll forming process, i.e. the ’unknown’ spring effect acting of the top roll during the forming process due to the implementation of Belleville washers in the pillar set up. This parameter is assessed over a range of applied loads and compared with a standard friction model with fixed top and bottom rolls. The longitudinal strains on the final profile, the geometric accuracy and thickness variation are observed and presented in this paper. Reasoning is also provided to explain why the final profile bows in the vertical direction.

Abstract: Cold roll forming is a process for plastic deformation, which allows realizing profiles, with a defined section and established length, from the plastic deformation of a metal sheet. The sheet is induced to cross several stands of rolls, arranged along the same axis of advancing. The rolls induce plastic deformation in the sheet and then lead it to the desired geometric configuration. In order to control the geometric parameters of the plate during the profiling, it was created a FEM model to simulate the final stage of the technological process, developed by an industrial production line of a company located in Naples (Italy), that sells tubes with several cross sections. In this phase, the semi-finished product, having a circular cross section, is forced to cross through four stands of rolls. In this way, it changes the geometric condition of the cross section from circular to square. The model was carried out using a non-linear calculation code, which allows analyzing the parameters of interest in the different process steps. The results, obtained numerically, were compared with the experimental ones through the measurement of five specimens, obtained directly from technological process. The values of percentage deviation, regarding the external dimension and the thickness, for each step of advancement, do not exceed the 3% of error. Then, the analysis results denote the capability to simulate the cold roll forming process using finite element method.

Abstract: In recent several years, although production of magnesium has risen dramatically, production of magnesium alloy sheet remains still at a very low level in practical use. The major barrier to greatly increased magnesium alloy use has been in still primarily high manufacturing cost as well as poor work ability of wrought magnesium sheet alloys. One of the author has investigated in cold roll forming of magnesium alloy, however detailed forming characteristics of the wrought magnesium alloy sheets has not been clarified. The aim of the study is to confirm possibilities of practical use of wrought magnesium alloy by using told roll forming process. A three dimensional elasto-plastic analysis by finite element method (FEM) has been conducted to examine the shapes of cross section, spring back characteristics, bending strains and longitudinal membrane strain of magnesium alloy sheet and cold rolled steel sheet during forming.

Abstract: In this paper, based on the engineering vehicle’s side plate cold roll forming machine developed by a company, we use 3D solid modeling software Solid Works to complete the establishment of a 3D model. On the basis of explicit dynamics elastoplastic finite element method basic theory, we make numerical simulation analysis of the metal plate’s forming process by using ANSYS/LS-DYNA module. According to the simulation results, we make repeated adjustment and optimization on its pass system and parameters. Through the numerical simulation of the forming process, we conclude the stress-strain distribution of the sheet metal. For similar products, the result has a certain reference value to the research of cold roll forming process and the design of cold roll forming equipments.

Abstract: The traditional LD type electric single-girder crane beam is made from several U type grooves by welding them together. For many years, U type groove is usually made from 5mm or 6mm steel plate which is stamped and formed by rolling machine. Through analysis of the problems and the disadvantages about the traditional producing process of LD type electric single-girder crane girder, put forward the improvement of cold roll forming process. The process has no welding seam, and allows a girder manufacture to achieve higher quality and efficiency, and has low consumption, low pollution.

Abstract: In this paper the explicit dynamic finite element method with the software of ANSYS/LS-DYNA to simulate the cold-roll forming process of special-channel steel sheet is studied, and it can reveal the forming rule, and analyze mechanical performance, which has specific theory significance and application value.

Abstract: According to the large deformation elastic-plastic FEM and contact theory, Through the cold roll forming numerical simulation of involutes spline by the finite element software ANSYS, studied with the key techniques of numerical simulation of the large displacements, large rotations, large elastic-plastic deformation under the highly complex nonlinear and the action of friction.

Abstract: The paper describes the research on deformation mechanism method of channel steel cold roll forming by finite element software ABAQUS, and typically analyzes stress and strain change rule of the fifth pass cold-formed process. Simulation results show that: on the whole, the equivalent strain and stress value of three typical parts tend to increasing with time increases

Abstract: During the cold rolling forming of non-symmetric Z-section steel, the twist will appear because two sides of the blank suffering bending moments of the same direction. In this paper, simplified FE model was used to simulate the closing process of the rolls. The contact forces of the rollers on blank, and the stress and strain of the blank was obtained by FE analysis, and relations between section torque and the position angle θ as studied and the result that when θ=10⁰ the torque is minimum was discovered. The further detailed calculations showed that angle θ was only correlative with the geometry of the product section and didn’t change with the altering of material properties.