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An automated sheet‐metal manufacturing systems for low‐volume production utilises an industrial robot to move blanks from a store to a press brake.

The automotive industry is very interested in sheet metal forming simulation using numerical techniques such as the finite element method. A cooperative research program between the Stamping Division of FIAT Auto and the Mechanics Department of the Politecnico di Torino was established with the aim of exploring the present possibilities of these techniques. This paper deals with the simulation of the deep forming of an axisymmetrical component, the axisymmetry being characterized by a double curvature profile, and is considered to be the first feasibility study. A sheet was modelled by fournode axisymmetric elements; the punch, the die and the blankholder were modelled by gap elements. The metal sheet was free to move along the punch and the die edges, with a continuous variation of the boundary conditions. The highly non‐linear problem requires an adequate description through the carefully considered use of the appropriate options of the MARC package (release K2). Moreover, some subroutines were written ad hoc to complete the discretization. Results are presented as strain and stress histories during the stamping process and as total forming force exerted by the punch to deform the sheet. In addition the spring‐back phase was considered in order to calculate the back deformation and the residual stress. Lastly, a comparison of the behaviour obtained with two different kinds of steel are reported.

July 13, 1967 Revenue — Selective employment tax — Sub‐contractors supplying manufacturer with metal blanks — Sheet metal bought from general stockists — Metal cut to manufacturers' precise specifications — Whether sub‐contractors “dealers” engaged in “Distributive trades” — Whether “Manufacturing Activities” — Whether “Metal industries” — Selective Employment Payment Act, 1966 (c. 32), s.1(2)(a), (b) — Standard Industrial Classification Orders IX, XVI, XX.

Traditional procedures in flat pattern design of aircraft sheet metal parts are generally based on technicians' personal idea and experiences which can cause unwanted inconsistency and errors. The main objective of this paper is to present an automated system for decreasing the time and increasing the accuracy in providing templates used in aircraft sheet metal parts manufacturing.

The paper discusses the software (Developer) which is able to receive 2D drawing of a part and create the flat pattern template after applying the necessary changes. The system is also capable of supplying other components of sheet metal part template such as support, tooling hole, and lightening hole. AutoLISP has been used as a tool for internal access to a commercial software such as AutoCAD. An interface has been written by Visual Basic for Application (VBA) to enable the user easily to apply the subroutines related to the software system.

Several algorithms have been developed and the necessary subroutines have been written in an integrated user‐friendly package. To clarify the process and its application, an application example is demonstrated.

The paper can provide automatically components that are not originally provided in other commercial software. It also has the ability to calculate spring‐back and provide unfold drawing. The known standard templates can also be created.

TWO‐YEAR atmospheric exposure tests of a number of sheet metals used in building construction have recently been completed by the U.S. National Bureau of Standards. Sheets of aluminium and zinc alloys and of aluminium‐coated and galvanised steel were exposed to the weather under conditions closely approximating those found in actual practice. Each metal tested was fastened to bare wooden boards with nails of various materials, both with and without neoprene or lead sealing washers between the nail head and the sheet. The study was conducted by T. H. Orem of the Bureau's corrosion laboratory.

This paper aims to identify issues with joining selective laser melting (SLM) steels with conventional cold rolled steels through remote laser beam welding.

A novel approach for substituting conventional cold rolled metal sheets with SLM metal sheets, made of 316L and 18-Ni 300, is presented. The characteristics of the interaction of wrought and SLM materials are described, and joining benchmark parameters are presented and compared to known existing joining results. Finally, the joints are assessed in line with automotive specifications. This research also addresses the importance of joining technologies for the implementation of SLM as a full-fledged manufacturing technology for the automotive industry.

New parameter ranges for laser beam welding of SLM steels are defined.

This research is limited to the examined steels and the used machines, parameters and equipment.

The presented benchmark parameters are expected to be useful for designers, product developers and machine operators.

Little knowledge is available about the behavior of SLM materials and their suitability for assembly processes. Novel information about SLM steels and their interaction with conventionally produced steel sheets is presented.

In manufacturing, dedicated machine tools and flexible machine tools are failing to satisfy the ever-changing manufacturing demands of short life cycles and dynamic nature of products. These machines are limited when new product designs are introduced. The solution lies in developing responsive machines that can be adjusted or be changed functionally when these change requirements arise. These machines are reconfigurable machines which are becoming the new focus, as they rapidly respond to product variety and volume changes. A sheet metal working machine known as a reconfigurable guillotine shear and bending press machine (RGS&BPM) has been developed. The purpose of this paper is to present a methodology, function-oriented design approach (FODA), which was developed for the design of the RGS&BPM.

The design of the machine is based on the six principles of reconfigurable manufacturing systems (RMSs), namely, modularity, scalability integrability, convertibility, diagnosability and customisability. The methodology seeks to optimise the design process of the RGS&BPM through a design of modules that make up the machine, enable its conversion and reconfiguration. The FODA is focussed on function identification to select the operational function required. Two main functions are recognised for the machine, these being cutting and bending; hence, the design revolves around these two and reconfigurability.

The developed design methodology was tested in the design of a prototype for the reconfigurable guillotine shear and bending press machine. The prototype is currently being manufactured and will be subjected to functional tests once completed. This paper is being presented not only to present the methodology by to show and highlight its practical applicability, as the prototype manufacturers have been enthusiastic about this new approach.

The research was limited to the design methodology for the RGS&BPM, the machine which has been designed to completion using this methodology, with prototype being manufactured.

This study presents critical steps and considerations in the development of reconfigurable machines. The main thrust being to explore the best possibility of developing the machines with dual functionality that will assist in availing the technology to manufacturer. As the machine has been development, the success of the design can be directly attributed to the FODA methodology, among other contributing factors. It also highlights the significance of the principles of RMS in reconfigurable machine design.

The RGS&BM machine is an answer for the small-to-medium enterprises (SMEs), as the machine replaces two machines with one, and the methodology ensures its affordable design. It contributes immensely to the machine availability by eliminating trial and error approaches.

This study presents a new approach to the design of reconfigurable dual machines using principles of RMS. As the targeted market is the SME, it is not limited to that as any entrepreneur may use the machine to their advantage. The design methodology presented contributes to the body of knowledge in dual reconfigurable machine tool design.

The purpose of this paper is to propose and analyse computationally a new concept for mechanical interlocking between metal and plastics. The approach utilizes some of the ideas used in the spot‐clinching joining process and is appropriately named “clinch‐lock polymer metal hybrid (PMH) technology.”

A new approach, the so‐called “direct‐adhesion” PMH technology, is recently proposed Grujicic et al. to help meet the needs of automotive original equipment manufacturers and their suppliers for a cost‐effective, robust, reliable PMH technology which can be used for the manufacturing of load‐bearing body‐in‐white (BIW) components and which is compatible with the current BIW manufacturing‐process chain. Within this approach, the necessary level of polymer‐to‐metal mechanical interconnectivity is attained through direct adhesion and mechanical interlocking.

In an attempt to fully assess the potential of the clinch‐lock approach for providing the required level of metal/polymer mechanical interlocking, a set of finite‐element based sheet‐metal forming, injection molding and structural mechanics analyses is carried out. The results obtained show that stiffness and buckling resistance levels can be attained which are comparable with those observed in the competing injection over‐molding PMH process but with an ∼3 percent lower weight (of the polymer subcomponent) and without the need for holes and for over‐molding of the free edges of the metal stamping.

The paper presents a useful discussion of clinch‐lock joining technology's potential for fabrication of PMH load‐bearing BIW components.

The great fluidity of titanium metal in the molten condition lends itself to fusion welding without the addition of filler metal. The resulting welds are flush with the base metal and have high ductility, comparable to the ductility of the base metal. The welded joints can be made by hand or automatic methods. A critical requirement of this type of weld is fit‐up of the parts to be joined. The back‐up and hold‐down fixtures also have a decided effect on the resulting weld. A sheared surface resulting in a joint without gaps is required for a satisfactory weld. Fused welds have been principally used, to date, for longitudinal tight butt joints in material up to .062 in. thick. Further testing and experience should extend the limits of application. Bend tests made on welded samples have bent 180 deg. over a 2T bend radius exhibiting equal or greater ductility than the base metal. Welds tested in tension have exhibited over 100 per cent efficiency in all cases. The elimination of welding rod has reduced the amount of contamination in the weld and the weld area.

The purpose of this paper is to analyze theoretically the influence of normal stress on the formability of aluminum alloy sheets in non-linear strain paths.

Four loading modes of non-linear strain paths are investigated in detail to consider the effect of normal stress on formability of aluminum alloy sheets.

Results show that the influence of normal stress in the first stage can be ignored. However, the normal stress in the second stage enhances the formability of aluminum alloy sheets obviously. Besides, the normal stress in the second stage is found to have larger effect on forming limit stress than that in the first stage.

Maybe more experiment data should be obtained to support the theoretical findings.

This current study provides a better understanding of normal stress effect on the formability of aluminum alloy sheets in non-linear strain paths. Since the reacting stage of normal stress play important roles in normal stress effect on the formability of aluminum alloy sheets, the insight obtained in this paper will help to judge the instability of aluminum alloy sheets in complex forming processes with normal stress reacting on the sheet or tube.