ANALYSIS OF RUBBER FORMING PROCESS OF FIRE BARRIER FROM TITANIUM CP2 ALLOY FOR AW 139 HELICOPTER

Wrinkling is one of the main failure modes in sheet metal forming process and may lead to assembly problems of the parts. Control of wrinkling is difficult due to the complex deformation behavior of the sheet metal. A finite element model for side blankholder method to control wrinkling was established and used for the simulation. Trials and simulations were conducted to analyze the parameters of wrinkling characteristics. Results show that with the increase in the angle of the side blankholder, the resistance force of the side blankholder decreases. The blank length on the side blankholder should be small enough. The fillet radius of the side blankholder should be large enough to reduce the deformation. The bottom gap between the die and the side blankholder cannot be too large because the support of the blank will decrease in the forming process. In order to verify the simulation results, three blank lengths (20, 15, and 5 mm) over the side blankholder were used in the experiment. The results of the comparison tests testify the reliability of the simulation. The optimal parameter of the blank length is 5 mm. A new clamp method was designed for wrinkling control to overcome the shortcomings of the side blankholder method. The precision of the part met the requirement using soft rubber and two layers of rubber plates.

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Research on One-Time Forming Process of Matrix PDC Bits

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.156-157.190 ◽

2010 ◽

Vol 156-157 ◽

pp. 190-193

Author(s):

Zhong Liang Wei ◽

Hang Wen ◽

Qing He ◽

Jin Mei Sun

Keyword(s):

High Precision ◽

Silicone Rubber ◽

Production Efficiency ◽

Graphite Powder ◽

Technical Program ◽

Forming Process ◽

Increase Production Efficiency ◽

Good Consistency ◽

Rubber Forming ◽

Powder Forming

Due to the difficulty in the ceramic mould forming process of matrix PDC bits and low production efficiency, a manufacturing mould technology of graphite powder forming process was developed. The technical program is to formulate a circuit of silicone rubber forming process, determine the forming process of first mould, rubber mould and graphite powder mould, and sinter bit. The results show that manufacturing bit mould to sinter PDC bits with this method can simplify the circuit, increase production efficiency, and improve bit quality. The resulting bit is also of high precision, exquisite appearance and good consistency

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Effect of process parameters on forming depth of channels in fuel cell bipolar plates fabricated using rubber forming process

Materials Research Innovations ◽

10.1179/1432891714z.000000000461 ◽

2014 ◽

Vol 18 (sup2) ◽

pp. S2-467-S2-472 ◽

Cited By ~ 4

Author(s):

C. K. Jin ◽

M. G. Jeong ◽

C. G. Kang

Keyword(s):

Fuel Cell ◽

Process Parameters ◽

Bipolar Plates ◽

Forming Process ◽

Rubber Forming

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Forming Limits for Shrink Flanges of Rubber Formed Parts

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.504-506.1255 ◽

2012 ◽

Vol 504-506 ◽

pp. 1255-1260 ◽

Cited By ~ 1

Author(s):

J. Sinke

Keyword(s):

Local Geometry ◽

Aircraft Industry ◽

Forming Process ◽

Forming Limits ◽

Alternative Approach ◽

Metal Sheets ◽

Rubber Forming ◽

Formed Part ◽

Ideal Process ◽

Number Of Authors

Rubber forming is an ideal process for the manufacture of a wide variety of flanged parts in small products series, and is attractive for industries like the aircraft industry. The flanges of a formed part are straight, stretch or shrink flanges, each type having its own limits. The forming limits for the straight and stretch flanges are dominated by the formability of the material and the applied strains, which are related to the (local) geometry of the flange. The prediction of the limits for the shrink flanges is much more complicated, since both plastic flow and instability play a role. In recent years, a number of authors developed methods for the prediction of wrinkle formation in metal sheets in different applications. This paper focuses on an alternative approach for the prediction of failure limits of shrink flanges. Shrink flanges wrinkle right from the start of forming process. At first the deformations are elastic, but for the creation of flanges the material has to become plastic. The geometry of the cross-section of the wrinkles can be approximated by sinusoidal shapes having a length and amplitude. During processing the values of both parameters decrease, although the ratio of the two is even more important and should decrease in order to obtain a wrinkle-free part. In the paper the topic is addressed using experimental data, showing the influence of the most important variables like materials properties, strain values, and variables like thickness. Subsequently the parameters are used to provide relations between the different variables, which are used for numerical simulations.

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Computer Aided Modelling of Rubber Pad Forming Process

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.473.637 ◽

2011 ◽

Vol 473 ◽

pp. 637-644 ◽

Cited By ~ 5

Author(s):

Antonio del Prete ◽

Gabriele Papadia ◽

Barbara Manisi

Keyword(s):

Sheet Metal ◽

Process Model ◽

Process Analysis ◽

Low Cost ◽

Critical Parameters ◽

Forming Process ◽

Small Series ◽

Rubber Pad Forming ◽

Rubber Forming ◽

Rigid Die

Rubber pad forming (RPF) is a novel method for sheet metal forming that has been increasingly used for: automotive, energy, electronic and aeronautic applications [1]. Compared with the conventional forming processes, this method only requires one rigid die, according to the shape of the part, and the other tool is replaced by a rubber pad [1]. This method can greatly improve the formability of the blank because the contact surface between the rigid die and the rubber pad is flexible. By this way the rubber pad forming enables the production of sheet metal parts with complex contours and bends. Furthermore, the rubber pad forming process is characterized by a low cost of the die because only one rigid die is required [2]. The conventional way to develop rubber pad forming processes of metallic components requires a burdensome trial-and-error process for setting-up the technology, whose success chiefly depends on operator’s skill and experience [4][5]. In the aeronautical field, where the parts are produced in small series, a too lengthy and costly development phase cannot be accepted. Moreover, the small number of components does not justify large investments in tooling. For these reasons, it is necessary that, during the conceptual design, possible technological troubles are preliminarily faced by means of numerical simulation [4],[6]. In this study, the rubber forming process of an aluminum alloy aeronautic component has been explored with numerical simulations and the significant parameters associated with this process have been investigated. Several effects, depending on: stamping strategy, component geometry and rubber pad characterization have been taken into account. The process analysis has been carried out thanks to an extensive use of a commercially finite element (FE) package useful for an appropriate set-up of the process model [7],[8]. These investigations have shown the effectiveness of simulations in process design and highlighted the critical parameters which require necessary adjustments before physical tests.

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Numerical Simulation and Experiment of Aluminum Sheet Metal Springback in New Quenching State

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.97-101.2567 ◽

2010 ◽

Vol 97-101 ◽

pp. 2567-2570

Author(s):

Lei Chen

Keyword(s):

Numerical Simulation ◽

Tensile Strength ◽

Numerical Method ◽

Sheet Metal ◽

Total Elongation ◽

Forming Process ◽

Tool Shape ◽

Metal Rubber ◽

Rubber Forming ◽

Simulation And Experiment

2024-T3 aluminium sheet metal rubber forming process after quenching is studied. The tensile properties of 2024-T3 after quenching are measured. It is found that the yield strength and ultimate tensile strength are reduced, whilst total elongation value is increased. Springback character of rubber forming is studied by numerical method and springback compensation of rib flanging is studied. The simulation is compared with experiment. It is found that the tool shape considering springback is got using numerical method. The parts after springback achieve the design accuracy. So the method can be used in the application of rubber net forming.

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