Search results for "Tamping"

Optimal positioning of irregular shapes in stamping die strip

2010

The nesting of two-dimensional shapes is a common problem, where raw material has to be economically cut. As for the single-pass single-row strip layout, several algorithms, based on established methods, have been proposed. Moreover, it should be noticed that the optimum layout should also consider a few constraints, like grain orientation for subsequent forming operation, correct bridge width, and the commercial roll of metal width in order to make solutions applicable in real industrial environments. Most of the procedures until now shown in literature are quite complex and often ignore these real constraints. They usually make use of sliding techniques and are not able to effectively wor…

Forming of aluminum foam sandwich panels: Numerical simulations and experimental tests

2006

Abstract The forming of the completed aluminium foam sandwich (AFS) panels would determine an improvement in the manufacturing of parts and panels. In this paper the authors have investigated the formability of AFS through experiments and numerical simulations. As far as the former are concerned, commercially prepared panels have been considered and bending and stamping processes have been taken into account. In addition, FEM analyses have been developed, utilizing a porous material model following the evolution of the material density throughout the forming processes.

Shape Distortion and Thickness Distribution during SPIF Processes: Expermental and Numerical Analysis

2011

Single Point Incremental Forming (SPIF) is a quite new sheet forming process which offers the possibility to deform complex parts without dedicated dies using only a single point tool and a standard 3-axis CNC machine. The process mechanics enables strains much higher than traditional sheet forming processes, but particular attention must be given to the final part geometrical accuracy. In this paper the capabilities of a dedicated explicit numerical model are quantitatively analyzed on pyramid-shaped parts. In particular a comparison between experimental and numerical results is reported. Three different shapes at the varying of the stamping angle were considered and the final shape was ac…

Springback effect evaluation in three-dimensional stamping processes at the varying of blankholder force

2006

The quantitative evaluation of elastic springback in sheet metal stamping processes is still today a very interesting research topic, since this phenomenon causes a manufacturing shape defect. A measurement technique based on the shadow moiré method, already developed by the present authors, has been further upgraded and applied to evaluate the springback phenomenon in the deep drawing of square boxes, the basic three-dimensional stamping process. In particular this technique is able to determine the final lateral surface of the drawn parts, once extracted from the dies, and to compare such surface with the ideal one derived from the die's computer-aided design (CAD) geometry. Proper quant…

Design of complex sheet metal forming processes: a new computer aided progressive approach

2010

The growing interest in sheet metal stamping processes, particularly in automotive industry, led to three main issues in this field: request of very complex shapes; growing interest in springback control; solution of multi-objective problems. This makes the design of the sheet metal stamping processes very difficult, since the number of both design variables and design objectives are progressively increased; therefore, proper design methodologies to reduce times and costs are highly required. In this paper, an innovative design approach able to manage and optimize complex stamping operations is proposed. In particular, a progressive design approach based on the integration between numerical…

The evaluation of springback in 3D stamping and coining processes

1998

Abstract An effective predictive technique of the elastic springback in a fully 3D 90° V-punch V-die bending process is presented. This is based on a combined approach in which an explicit finite element code was used to simulate the loading phase of the process whilst an implicit procedure was used to analyse the springback phase. Two different punches with a nose radius of 4 and 8 mm were used. An increase in the springback ratio with the coining load was observed with the lower nose radius. Conversely, an increase in the springback ratio with the coining load up to a peak value (>1), corresponding to a force of about 20 kN, followed by a decrease in the springback ratio with increasing t…

DIMENSIONAL STABILITY OF REINFORCED MATRICES.

1983

Particulate fillers are often used to improve the dimensional stability of polymeric items obtained through processing techniques such as injection molding, deep drawing, hot stamping, etc. In these operations the material undergoes large multiaxial deformations which result in molecular orientation and remain as frozen-in stresses during cooling of the material. Once the formed objects are exposed to sufficiently high temperatures, various degrees of spring-back take place and subsequent changes in shape and dimension occur (1).

SHEET STAMPING PROCESSES DESIGN: OPTIMIZATION METHODOLOGIES FOR ROBUST AND ENVIRONMENTAL CONSCIUS DECISION.

2012

Sheet Stamping Processes Design: Optimization Methodologies for Robust and Environmental Conscious Decisions.

2012

A sustainability point of view on sheet metal forming operations: material wasting and energy consumption in incremental forming and stamping process…

2012

Abstract Sustainability and sustainable production is nowadays a wide research field due the urgency of reducing environmental burdens of industrial production. Sustainable manufacturing issues are widely investigated too. In particular, due to the relevance such issues assume for automotive and aeronautical industry, the investigation of sheet metal forming processes sustainability is worth studying and, within this research fields, a certain lack of knowledge is still present. Many studies have been presented concerning the evaluation and reduction of environmental burdens in manufacturing. In this paper, the authors focus on sheet metal forming and aim to investigate both the efficient u…