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The purpose of this paper is to examine the effect of changing some riveting parameters on the riveting quality of a riveted aircraft structure. In this study, riveting was performed by applying friction under pressure.

During this friction riveting process, a feed of 3 mm/min was applied in the axial direction. Rotation speed values of 2,000, 2,200 and 2,400 rpm were selected. A 3-axis die milling machine was used to achieve the required positioning, pressing force and friction effect. 1.27 mm-thick Al 7075-T6 sheets and 2117-T3 forged rivets were used. The feed rate was applied at 1 mm/min in both tensile shear and cross-tensile tests.

The feasibility of friction riveting in 2117-T3 rivets was examined, it was shown that it could be done, and the most suitable rotation value for this process was determined.

Clamping force is one of the most important parameters for riveting quality. This study will contribute to a better understanding of the friction-forging riveting process along with the effects of riveting parameters. At the same time, it will lead to more research and expand the application of friction forging riveting to more structural connections.

The purpose of this paper is to design, analyze and optimize a new type of inner-side working head for automatic horizontal dual-machine cooperative drilling and riveting system. The inner-side working head is the key component of automatic drilling and riveting system, and it is a challenge to design an inner-side working head which must be stiffness and stable with a compact structure to realize its functions.

According to the assembly structure features of large aircraft panels and riveting process requirements, a new type of inner-side working head is designed for pressure riveting. The force condition of the inner-side working head during the riveting process is analyzed and the deformation model is established. Design optimization is performed based on genetic algorithm and finite element analysis. The optimized inner-side working head is tested with automatic horizontal dual-machine cooperative drilling and riveting system.

The deformation model provides the precision compensation basis for control system. Application test results show that the automatic drilling and riveting system can realize assembly of large aircraft panel with high efficiency and quality through the inner-side working head.

The inner-side working head has been used in aircraft panel assembly.

The inner-side working head has been used in aircraft panel assembly.

This paper presents the design, analysis and optimization of a new type of inner-side working head which can realize automatic riveting for aircraft panel. The research will promote the automation of aircraft panel assembly.

The purpose of this paper is to propose a computational approach in order to help establish the effect of various self-piercing rivet (SPR) process and material parameters on the quality and the mechanical performance of the resulting SPR joints.

Toward that end, a sequence of three distinct computational analyses is developed. These analyses include: (a) finite-element modeling and simulations of the SPR process; (b) determination of the mechanical properties of the resulting SPR joints through the use of three-dimensional, continuum finite-element-based numerical simulations of various mechanical tests performed on the SPR joints; and (c) determination, parameterization and validation of the constitutive relations for the simplified SPR connectors, using the results obtained in (b) and the available experimental results. The availability of such connectors is mandatory in large-scale computational analyses of whole-vehicle crash or even in simulations of vehicle component manufacturing, e.g. car-body electro-coat paint-baking process. In such simulations, explicit three-dimensional representation of all SPR joints is associated with a prohibitive computational cost.

It is found that the approach developed in the present work can be used, within an engineering optimization procedure, to adjust the SPR process and material parameters (design variables) in order to obtain a desired combination of the SPR-joint mechanical properties (objective function).

To the authors’ knowledge, the present work is the first public-domain report of the comprehensive modeling and simulations including: self-piercing process; virtual mechanical testing of the SPR joints; and derivation of the constitutive relations for the SPR connector elements.

This study aims to investigate the effect of countersunk rivet head dimensions on the fatigue performance of the riveted specimens of 2024-T3 alloy.

The relationship between rivet head dimensions and fatigue behavior was investigated by finite element method and fatigue test. The fatigue fracture of the specimens was analyzed by scanning electron microscopy.

A change of the rivet head dimensions will cause a change in the stress concentration and residual normal stress, the stress concentration near the rivet hole causes the fatigue crack source to be located on the straight section of the countersunk rivet hole and the residual normal stress can effectively restrain the initiation and expansion of fatigue cracks. The fatigue cycle will cause the rivet holes to produce different degrees of surface wear.

The fatigue life of the specimens with the height of the rivet head of 2.28 mm and 2.00 mm are similar, but the specimens with the height of the rivet head of 1.72 mm were far higher than the other specimens.

The purpose of this paper is to investigate a possibility of determination of the rivet hole expansion with the use of computed tomography (CT). This method offers several benefits in comparison to the traditionally used destructive methods.

The measurements of rivet hole expansion were performed on three specimens with the use of CT. Then, the same specimens were measured with the use of the conventional destructive method. This allows to estimate accuracy of the proposed method and characterize its advantages and limitations.

Good correlation with the destructive method has been obtained. The proposed method enables more detailed analysis of a joint as arbitrarily oriented cross-section for analysed area can be easily generated and increase of measurements number is always possible and simple. The disadvantage of the method is lower accuracy of diameter determination than in the case of conventional methods.

The measurements were performed only on one type of specimens. Probably, if a rivet and sheets were made of the same alloy, the measurements would be barely possible. The rivets were installed with squeezing ratio D/Do = 1.7 whose value is close to maximum as defined in riveting instructions (Kaniowski, 2015). This means that measured hole expansions were higher than in typical joint. The proposed method is appropriate for simple specimens (one rivet at a specimen width).

The investigation shows that rivet hole expansion can be measured with the use of CT. This method is useful especially when destruction of a specimen is not allowed or more detailed analysis is required (e.g. measurements on many depth levels).

The paper presents measurements of rivet hole expansion with the method which has not been used before for this application. Advantages and limitations of the proposed approach compared to conventional methods are discussed.

HAVING completed the erection of all the frames, we can now turn our attention to the assembly and fitting of side keel‐sons and stringers. Side keelsons are usually fitted intercostally—that is, between frames—although a few boats have them fitted longitudinally. In my opinion, when intercostally fitted, they are much stronger and less trouble to assemble, and this type will eventually become standard. Being intercostal, they are very simple to make up owing to their short lengths. There is a slight difference between the design of a centre and a side keelson, the latter having only one angle fixed at the top and the bottom, forming a Z‐ The correct shape of the webs can be obtained from the lines on the scrive board, and after the web and angles have been shaped, the side keelsons should be drilled off, lightening holes punched, and sent to be anodically treated before being riveted up. When they are ready for erecting on the hull, their correct position is ascertained by means of the angle lugs that have been riveted on to the web of the frame. This will be found quite a simple operation, the point to watch being that when putting them into place they do not cause any distortion of the frames owing to incorrect length. They should only be hand tight, as any forcing into position will destroy the anodic films on both frame and keelson. They must be faired in by means of a wooden batten, which should be long enough to extend across three or more frames.

Jaguar Cars, the luxury UK automaker, is developing a new car, the X350. For the first time, the company is to use aluminium body panels for the body shell. Aluminium can be difficult to weld so self‐piercing rivets are used for metal joining. The rivets are used in place of spot welding, but are applied by rivet setters attached to robots.

To review the capabilities of a new method of welding aluminium sheets for car body construction.

Describes the friction spot joining technique, and how it differs from friction stir welding. Describes the tests carried out at the University of Warwick to compare this with other aluminium sheet joining techniques.

Compared with resistance spot welding, this technique is simple, and physically and electromagnetically clean. Its low energy requirement per joint and low running costs give it advantages in joining thin materials, and eventual recycling is much easier than with self‐piercing riveting joints.

Describes the motivation behind the continuing development of an all‐aluminium joining technique, and compares spot friction joining with self‐pierce riveting and resistance spot welding.

THE “Do.X 1” was launched on July 12, 1929, hence we can now look back on the experience collected in the operation of this new aircraft over two and a half years. This experience has been gained with three different types: the original type aircraft, or “Do X.1” (Fig. 1), with air‐cooled engines; the same aircraft in its modified form, the “Do.X.1a” (Fig 2), with water‐cooled engines, and the “Do.X.2” (Umberta Maddalena), the first of two flying boats built on behalf of an Italian firm, with water‐cooled Fiat engines. (Fig. 3.)

The riveting process is a metal forming process involving complex elastic-plastic deformation, which will induce a compressive residual stress field and cause local distortions in the connecting areas. Regarding to the aircraft panel assemblies with plenty of rivets, the global deformation is inevitable and undesired, leading difficulties to downstream assembly processes. This paper aims to present a new method for the local distortion calculation and the global deformation prediction of sheet panel assemblies during the automated riveting process.

In this paper, a simplified algebraic study is presented to analyze the local distortion of single countersunk rivet joint with the consideration of the barrel-like shape of the driven head and the through-thickness variations along the rivet shank. Then, an equivalent rivet unit is proposed based on the result of the algebraic study and embedded into the global-level model for the prediction of the overall distortions of riveted panels.

The algebraic study is able to reach a more precise contour of the deformed rivet than the traditional assumption of cylindrical deformations and rapidly determine the equivalent coefficients of the riveting unit. The result also shows an industrial acceptable accuracy of the prediction for the global deformations of the double-layered panel assemblies widely used in the aircraft panel structures.

A new local-global method for predicting the deformations of the riveted panel assembly based on the algebraic study of the local distortions is proposed to help the engineers in the early design stages or in the assembly process planning stage.