scholarly journals Comparative Studies of the Seatings of Propulsion Plantsand Auxiliary Machinery on Chocks Made of Metal and Cast from Resin Part II. Mounting on Cast Resin Chocks

2020 ◽  
Vol 27 (1) ◽  
pp. 126-133
Author(s):  
Paweł Grudziński ◽  
Konrad Konowalski
Keyword(s):  
Comparative Analysis ◽  
Comparative Studies ◽  
Research Work ◽  
Experimental Studies ◽  
Bolted Joints ◽  
Bolted Joint ◽  
Structural Damping ◽  
Relevant Research ◽  
Resin Part ◽  
Plant Components

AbstractThis article is Part II of the paper containing a description and results of the experimental studies of the deformations, friction processes and structural damping that occur in the foundation bolted joints of propulsion plant components and auxiliary machinery installed on sea-going ships. Part I of this research work presents an analysis of the rigid mountings of machines and devices to the foundations on steel or resin chocks, and explains the need to carry out relevant research in this area. It also presents the description and results of experimental studies carried out for a foundation bolted joint with a conventionally used steel chock. Part II (this article) contains a description and results of similar studies carried out for a foundation bolted joint with a modern chock – cast from epoxy resin compound (EPY), specially developed for this purpose. Then, a comparative analysis of the results obtained for both bolted joints in question was made and the foundation chocks of the poured-in-place resin compound were demonstrated to better fulfill their technical tasks than the steel chocks traditionally used for this purpose.

scholarly journals Comparative Studies of the Seatings of Propulsion Plants and Auxiliary Machinery on Chocks Made of Metal and Cast of Resin Part I. Mounting on Steel Chocks

2019 ◽  
Vol 26 (4) ◽  
pp. 142-148
Author(s):  
Paweł Grudziński ◽  
Konrad Konowalski
Keyword(s):  
Comparative Analysis ◽  
Scientific Explanation ◽  
Experimental Studies ◽  
Point Of View ◽  
Bolted Joints ◽  
Engineering Practice ◽  
Bolted Joint ◽  
Science And Engineering ◽  
Analysis And Evaluation ◽  
Resin Part

Abstract This paper presents a description and the results of experimental studies of the deformation, friction and structural damping occurring in foundation bolted joints of propulsion plant components and auxiliary machinery that is rigidly mounted on sea-going ships. The rigid mounting of these devices to the ships’ structural foundations can be implemented in a traditional way, i.e. on chocks made of metal (usually of steel), or in a modern way, i.e. on chocks cast of resin, specially designed for this purpose. The main goal of this study is to perform a comparative analysis of these two solutions and to give a scientific explanation for why chocks cast of resin perform better in machinery seatings than the steel chocks traditionally used for this purpose. The paper consists of two parts. Part I presents the details of the rigid mountings of machinery to the foundations, and contains the results of experimental studies performed on a model of a foundation bolted joint with a traditional steel chock. Part II contains the results of similar studies carried out for a model of a bolted joint with a modern chock cast of resin. Next, a comparative analysis and evaluation of the results obtained for both investigated bolted joints was carried out, and conclusions were formulated to highlight important aspects of the problem from the point of view of science and engineering practice.

Measurement of Bolt Clamping Forces by Electromagnetic Vibration Method Without Disassembling Bolted Joints

2006 ◽  
Author(s):  
Toshimichi Fukuoka ◽  
Nobukuni Sugano
Keyword(s):  
Contact Pressure ◽  
Experimental Studies ◽  
Service Condition ◽  
Point Of View ◽  
Bolted Joints ◽  
Joint Interface ◽  
Bolted Joint ◽  
Plate Interface ◽  
Vibration Method ◽  
Electromagnetic Vibration

The integrity and safety of a bolted joint can be greatly guaranteed by applying and maintaining an appropriate amount of bolt preloads. However, the variation of bolt preloads inevitably occurs in the service condition due to various reasons, even if the initial bolt preloads are properly applied. Accordingly, the monitoring of bolt forces in the service condition is significantly important. From the practical point of view, it is preferably conducted without disassembling the objective bolted joint. In this paper, Electromagnetic Vibration Method is introduced for monitoring the variation of bolt preloads in the service condition, and its performance is examined by experiments using bolted joints with various geometric configurations. Electromagnetic Vibration Method estimates the magnitude of bolt preload by measuring the resonant frequencies of the bolted joint, which vary in accordance with the contact pressure of the joint interface. From the experimental studies, Electromagnetic Vibration Method was found to be effective to evaluate the bolt force with a reasonable accuracy, except for the bolted joint whose plate interface being under very high contact pressure.

On the Use of Shape Memory Alloy Studs to Recover Load Loss in Bolted Joints

2013 ◽  
Vol 135 (2) ◽  
Author(s):  
Nazim Ould-Brahim ◽  
Abdel-Hakim Bouzid ◽  
Vladimir Brailovski
Keyword(s):  
Shape Memory ◽  
Analytical Model ◽  
Experimental Studies ◽  
Thermal Exposure ◽  
Element Model ◽  
Bolted Joints ◽  
Bolted Joint ◽  
Creep Properties ◽  
Material Creep ◽  
Joint Assembly

Creep is an important factor that contributes to the clamp load loss and tightness failure of bolted joints with and without gaskets over time. Retightening of the joint can be expensive and time consuming; therefore, it is an undesirable solution. Currently, most efforts are put towards reducing load losses directly by tightening to yield, improving material creep properties, or making joint less rigid. An alternative solution of current interest is the use of bolts in shape memory alloys (SMAs). However, very few experimental studies are available, which demonstrate the feasibility of these alloys. The objective of this study is to explore the benefit of shape memory and superelasticity behavior of an SMA stud to recover load losses due to creep and thermal exposure of a gasket in a bolted-joint assembly. This paper explores several venues to investigate and model the thermomechanical behavior of a bolted joint with a nickel–titanium SMA stud. A stiffness-based analytical model which incorporates the Likhachev model of SMA is used as a representation of an experimental bolted-joint assembly. Based on this model, the rigidity of the experimental setup is optimized to make the best use of the SMA properties of the stud. This analytical model is compared with a finite element model, which also implements the Likhachev's material law. Finally, an experimental test bench with a relatively low stiffness representative of standard flanges is used, with and without gaskets to demonstrate the ability of the SMA stud to recover load losses due to gasket creep.

Representation of bolted joints in a structure using finite element modelling and model updating

2020 ◽  
Vol 14 (3) ◽  
pp. 7141-7151 ◽  
Author(s):  
R. Omar ◽  
M. N. Abdul Rani ◽  
M. A. Yunus
Keyword(s):  
Finite Element ◽  
Dynamic Behaviour ◽  
Model Updating ◽  
Complex Structure ◽  
Bolted Joints ◽  
Model Parameters ◽  
Fe Model ◽  
Bolted Joint ◽  
Fe Modelling ◽  
Joint Structure

Efficient and accurate finite element (FE) modelling of bolted joints is essential for increasing confidence in the investigation of structural vibrations. However, modelling of bolted joints for the investigation is often found to be very challenging. This paper proposes an appropriate FE representation of bolted joints for the prediction of the dynamic behaviour of a bolted joint structure. Two different FE models of the bolted joint structure with two different FE element connectors, which are CBEAM and CBUSH, representing the bolted joints are developed. Modal updating is used to correlate the two FE models with the experimental model. The dynamic behaviour of the two FE models is compared with experimental modal analysis to evaluate and determine the most appropriate FE model of the bolted joint structure. The comparison reveals that the CBUSH element connectors based FE model has a greater capability in representing the bolted joints with 86 percent accuracy and greater efficiency in updating the model parameters. The proposed modelling technique will be useful in the modelling of a complex structure with a large number of bolted joints.

Valid Signature Detection and Verification for Security of Individual Person

2016 ◽  
Vol 1 (1) ◽  
pp. 50-53 ◽  
Author(s):  
Varun Sharma ◽  
Narpat Singh
Keyword(s):  
Neural Network ◽  
Comparative Analysis ◽  
Recent Work ◽  
Research Work ◽  
Early Research ◽  
Individual Person ◽  
Signature Detection ◽  
Online Signature ◽  
The Right ◽  
Handwritten Signature

In the recent research work, the handwritten signature is a suitable field to detection of valid signature from different environment such online signature and offline signature. In early research work, a lot of unauthorized person put the signature and theft the data in illegal manner from organization or industries. So we have to need identify, the right person on the basis of various parameters that can be detected. In this paper, we have proposed two methods namely LDA and Neural Network for the offline signature from the scan signature image. For efficient research, we have focused the comparative analysis in terms of FRR, SSIM, MSE, and PSNR. These parameters are compared with the early work and the recent work. Our proposed work is more effective and provides the suitable result through our method which leads to existing work. Our method will help to find legal signature of authorized use for security and avoid illegal work.

scholarly journals Experimental study of lateral resistance of bolted joints using Japanese cedar (Cryptomeria japonica) treated with resin impregnation

2020 ◽  
Vol 66 (1) ◽  
Author(s):  
Keita Ogawa ◽  
Satoshi Fukuta ◽  
Kenji Kobayashi
Keyword(s):  
Short Pulse ◽  
Japanese Cedar ◽  
Bolted Joints ◽  
Bolted Joint ◽  
Yield Load ◽  
Short Pulse Laser ◽  
Resin Impregnation ◽  
Lateral Resistance ◽  
Ultraviolet Wavelength ◽  
Resistance Performance

Abstract The development of wooden joints possessing high resistance performance has become an important issue for the construction of newer buildings. This study attempts to strengthen the lateral resistance of bolted joints using the previously reported plasticizing technique. This technique consists of two processing stages: incising the surface of the wood using an ultraviolet wavelength short-pulse laser and impregnating the resin into the incised area. This technique makes it possible to plasticize only a local part of the wood surface. Bolted joint specimens were assembled using plasticized wood around the bolt hole, and the lateral tests were conducted. Acrylic monomer and urethane prepolymer were used as the impregnating resins and their incision depths were set as 4 and 10 mm. When the lateral load acted parallel to the grain, changes in the lateral resistance characteristics were observed, especially for the stiffness and yield load. For example, when acryl was used, and the incision depth was 10 mm, an increment of 73% in the yield load was observed, as compared to the non-impregnated specimens. The specimen groups impregnated with acryl exhibited greater changes in their properties than those using urethane. When loaded perpendicular to the grain, an increase in properties were observed; however, these increments were lower than those of the groups loaded parallel to the grain.

Research on Signal Timing Method of Intersection Based on RFID

2011 ◽  
Vol 84-85 ◽  
pp. 410-414
Author(s):  
Wei He ◽  
Jie Xiong
Keyword(s):  
Comparative Analysis ◽  
Radio Frequency Identification ◽  
Main Parameter ◽  
Control Method ◽  
Research Work ◽  
Signal Timing ◽  
Key Points ◽  
Frequency Identification ◽  
New Research ◽  
Radio Frequency Identification Devices

Based on the RFID (Radio Frequency Identification Devices), this paper presents new research work of signal timing intersection in the aspects of the key points of design, the main parameter and timing methods. Finally, the intersection of signal timing of fuzzy control method based on RFID is proposed through comparative analysis of the intersection of several traditional signal timing methods.

Creative communication of artistic systems M. Tsvetaeva and B. Pasternak

2021 ◽  
Vol 6 (2) ◽  
pp. 74-82
Author(s):  
Anastasia Valerievna Sebeleva
Keyword(s):  
Comparative Analysis ◽  
Comparative Studies ◽  
Mutual Influence ◽  
Integrated Approach ◽  
Literary Studies ◽  
Textual Information ◽  
Priority Direction ◽  
Literary Process ◽  
History Of ◽  
Mutual Communication

This article proceeds from the fact that the problem of interaction and mutual influence is quite acute in literary studies. In this regard, the relevance of the research is due, firstly, to the correspondence to the priority direction of modern literary studies associated with the comparative analysis of the text, and secondly, to the need to disclose the deep theoretical and artistic content of creative communication of such artistic personalities of the XX century as M. Tsvetaeva and B. Pasternak, whose legacy still contains many lacunae. The methodological basis of the research is an integrated approach, including comparative-historical, historical-literary, comparative-typological, system-analytical and biographical methods, as well as the method of comparative studies, which allows to study literary analogies and connections of different national literatures, their refraction in the texts of the authors studied. Hermeneutics contributed to the mental comprehension of the analyzed texts, the mental processing of textual information. An important episode in the history of world poetry was the correspondence-dialogue of iconic poets for their time: M. Tsvetaeva and B. Pasternak. Correspondence is valuable not only because it shows us the life of poets in relation to time. The creative aspect of correspondence is very important. The rapprochement manifested in it and at the same time the repulsion was deeply creative and left deep traces in the legacy of all its participants. Poets, albeit to varying degrees, concentrated and passionately, sought to define for themselves the essence of life and poetry. In the course of the research, the author of the article comes to the conclusion that, firstly, the literary process is characterized by a systematic nature in which authors and their works are in certain relationships to each other. Secondly, the thirteen-year correspondence of M. Tsvetaeva with B. Pasternak was very significant for literature. Thanks to mutual communication, creative interaction, the poets created unique, emotionally deep works.

Accurate Evaluation of Bolt and Clamped Members Stiffnesses Of Bolted Joints

2021 ◽  
Author(s):  
Rashique Iftekhar Rousseau ◽  
Abdel-Hakim Bouzid ◽  
Zijian Zhao
Keyword(s):  
Finite Element ◽  
Joint Stiffness ◽  
Element Model ◽  
Fe Analysis ◽  
Bolted Joints ◽  
Analytical Models ◽  
Fe Modeling ◽  
Bolted Joint ◽  
A New Technique ◽  
External Loads

Abstract The axial stiffnesses of the bolt and clamped members of bolted joints are of great importance when considering their integrity and capacity to withstand external loads and resist relaxation due to creep. There are many techniques to calculate the stiffnesses of the joint elements using finite element (FE) modeling, but most of them are based on the displacement of nodes that are selected arbitrarily; therefore, leading to inaccurate values of joint stiffness. This work suggests a new method to estimate the stiffnesses of the bolt and clamped members using FE analysis and compares the results with the FE methods developed earlier and also with the existing analytical models. A new methodology including an axisymmetric finite element model of the bolted joint is proposed in which the bolts of different sizes ranging from M6 to M36 are considered for the analysis to generalize the proposed approach. The equivalent bolt length that includes the contribution of the thickness of the bolt head and the bolt nominal diameter to the bolt stiffness is carefully investigated. An equivalent bolt length that accounts for the flexibility of the bolt head is proposed in the calculation of the bolt stiffness and a new technique to accurately determine the stiffness of clamped members are detailed.

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