EDF Energy has the requirement to detect and size lack of penetration type defects in thin-walled stainless steel components. A high frequency ultrasonic phased array inspection technique has been successfully developed and applied to thin walled pipes and is currently used as an ENIQ qualified inspection on nuclear plant. The welds are manufactured with an autogenous Tungsten Inert Gas (TIG) w...

The axial crushing of thin-walled tubes has been the subject of extensive research in the past. The existing kinematic models for predicting crushing behavior of axially loaded thin-walled tubes are systematically reviewed and analyzed. The advantages and limitations of each model are discussed. A new chain link model for circular tubes and square tubes is presented and studied in detail. Unlik...

Experimentally determined natural frequencies and modes shapes are presented for an elastically point-supported isotropic plate with attached masses under impulsive loading. These results are compared to frequencies and to modes shapes determined from the Rayleigh–Ritz method and a finite element analysis using COMSOL. Accelerometers mounted at three locations on the plate, provide input for ME...

This paper presents a procedure to determine an element-length dependent strain and stress relation until fracture that is suitable for implementation in finite element models. This material relation is obtained experimentally with an optical measuring system. The strain until fracture is calculated from the measured surface displacements. The stress is derived from the measured force and the c...

assessing the behavior of composite structures which are subjected to impact loads is one of the important subjects in the field of mechanical sciences. using thin-walled tubes which collapsed and absorbed the impact energy is a well-known method to prevent damages to the other parts of the structures. in this paper, deformations, crushing length, peak load, mean force and energy absorption cap...

In this paper, acoustic radiation response of thin-walled box with particle dampers is predicted. First, the effect of the collisions and friction between the granular inter-particles is interpreted as an equivalent nonlinear viscous damping based on multiphase flow theory of gas-particle. Then the contribution of particle damper is estimated as an equivalent mass-damper system. And the acousti...

A 42-year-old female patient was admitted for recurrent bilateral spontaneous pneumothorax. High resolution computed tomography showed bilateral pneumothorax and numerous round and oval, thin-walled lung cysts. Microscopically, each small cyst was composed of distended subpleural alveolar spaces. Tumor cells, characteristic of acinar adenocarcinoma, obstructed and narrowed the terminal bronchio...

A closed form expression for the torsion constant of thin-walled multicell profiles is derived based on a simple algorithm to generate the coefficient matrix of the system of linear algebraic equations for the shear flows. New explicit results are given for the three-cell profiles with either two or three internal walls, and for the two-cell profiles. They are applied to derive the optimal loca...

To solve the problems that the low rigidity thin-walled part is easy to deform in NC milling process and some parts of the complex surface is difficult to process, this paper points out the measures for increasing accuracy of thin-walled NC machining process from the selection of material and blank, the choice of machine tool, the determination and optimization of the clamping method, the choic...