[en] A nuclear reactor fuel assembly in which the end fittings may be easily removed after the assembly has been irradiated so that defective fuel rods may be replaced or special fuel or burnable poison rods inserted therein. The fuel assembly is of the type wherein structural support is provided by several vertically extending hollow structural members attached at opposite ends to upper and lower end fittings. The upper and lower end fittings each comprise an end plate and means extending therefrom for alignment and support of the assembly within the reactor core. Threaded joints between the hollow structural members and the means for alignment form the connections between the hollow structural members and the upper and lower end fittings

[en] Bolted joint commonly being used as a mechanical joint to connect two or more mechanical components which bring an interest to this study. The complexity of joint element plays an important role in the dynamic investigation. Structural damage happens and often it’s too late to react to it and early detection of structure failure (damage) is beneficial. This paper aims to study the differences between undamaged and damage frame structure with bolted joints. Frame structure consists of 4 angle bar and 16 flat bars fabricated with stainless steel material is used. Total of 32 pcs of M6 screw and nuts are used together with structure. Damage often alter the mode shapes and reduce the natural frequencies. Natural frequencies and mode shapes of both undamaged and damaged data obtained by experimental modal analysis is correlated. Frequency drop is observed on natural frequencies after being correlated and as well as the mode shapes changed occurs on the undamaged and damages structure. Frame structure with damage on the joints able to detect the frequency drops and alter the modes shapes. (paper)

[en] The accurate measurement of the preloads introduced in bolted joints is nowadays frequently required. Ultrasonic pulses echographic methods should permit to solve this problem. The measurements made on 10-9 quality class M 16-80 bolts allow to quantify the propagation time as a function of stress within the bolt. The statistical treatment of those results points out a linear relation and a preload measurement accuracy of about 3%

[en] Dry connection of prefabricated concrete shear wall has gradually become a hot research direction in China, and among those various of dry connections, bolted joints attract scholars’ attentions with its unique advantages. This paper introduces the classifications of bolted joints of prefabricated concrete shear wall structures. Then it summarizes the latest developments of such joints in foreign countries, and the current research status in China. At the same time, this paper will give a comprehensive evaluation from the perspective of safety and cost. Finally, some suggestions are put forward for the problems still to be solved in this direction in the future. (paper)

[en] The identification of the dynamic properties of structural joints is important for predicting the dynamic behavior of assembled systems. However, the identification of the properties using analytical or experimental approaches is extremely difficult or even impossible. Several studies have proposed hybrid or synthesis methods that simultaneously used analytical and experimental approaches to identify the dynamic properties of a joint. However, among the many types of joints, only the bolt joint was treated as a practical example in these studies. In this study, for a simple assembly system comprising two plates and one hinge joint, a simple methodology involving the use of the static based subpart analysis method to identify the dynamic properties is proposed. Finally, the proposed method is applied to a glove box in a passenger vehicle that includes hinge joints

[en] Machine products are composed of numerous structural members and machine elements, held together with various types of connections, such as bolted joints or articulating members that provide for the required functions of the design and aim to satisfy the desired product performance. Such machine product designs routinely have so many mutually related characteristics that common design optimization methods often result in an unsatisfactory local optimum solution. In order to overcome this problem, this paper proposes a design optimization method for machine products that incorporates joint dynamics and is based on the decomposition of performance characteristics, and clarification of the conflicting relationships among the characteristics

[en] A synthesized technique to aid in predicting the overall dynamic or static response of a bolted connection to externally applied dynamic or static tractions is presented. The technique is a synthesis of an existing method for determining stiffness coefficients in a bolted connection together with concepts and analysis techniques presented in this document. The information presented is considered a ''first step'' in the development of an analytical technique for predicting the overall stiffness of a bolted connection having circular geometry

[en] A list of main directions in improving devices for setting and tightening of bolted joints is presented. A series of automatic complexes for mounting and dismounting covers of nuclear reactors is described. Problems of improving reliability of gasket seals and their bolted joints are discussed

[en] A vertical zircalloy shroud for a nuclear fuel cartridge encloses the upper part of the base part and is attached to the same by a number of horizontal bolts with countersunk conical heads. Around each bolt the base part have a milled recess on the surface thus forming an annular vertical gap. The gas allows the shroud to be deformed when the fuel cartridge is heated which means a reduction of the tension load in the bolts. (L.F.)

[en] Based on the problem of modal frequencies variation of bolted joint plate caused by the variation of bolt preloads, the purpose of this article is to propose a method of finding the best preload of bolted joint plate. Firstly, a modal analysis experimental system of bolted joint plates was set up. Subsequently, the modal frequency test of some bolted joint plates are completed. A method for designing the best preload of bolted joint plate was proposed in the end. Results indicate that the bolt preload has certain influence on modal frequency of bolted joint plate. The process of applying a preload to the bolt is regarded as the tightening of a bolt from loosen state to tighten state. As two loosen bolts are simultaneously tightened into tighten bolts, the modal frequencies is increased with a big magnitude. However, as one of loosen bolt is tightened to tighten bolt, but the other is unchanged, the modal frequencies is increased with a small magnitude. The sensitivity of first four modal frequencies of the jointed plate are different to the bolt preload. Therefore, working environment and working force of jointed plate must be considered in the dynamic design. Based on the experimental result, a best bolt preload design method of bolted joint plate in the dynamic design can be proposed. (paper)