The Experts below are selected from a list of 2220 Experts worldwide ranked by ideXlab platform

Muhammad Abid - One of the best experts on this subject based on the ideXlab platform.

  • INVESTIGATION OF RESIDUAL STRESSES AND DISTORTION IN WELDED PIPE-Flange Joint OF DIFFERENT CLASSES
    2016
    Co-Authors: Muhammad Abid, Sattar Ullah
    Abstract:

    ABSTRACT: Pipe and Flange Joints are commonly used in petrochemical, nuclear and process industries. Commonly, welding is used to make these Joints which produce residual stresses and distortions. These stresses have detrimental effects on the structural integrity and service performance of the welded pipe Joints. The objective of this study is to investigate the residual stresses and distortions during Gas Metal Arc Welding of pipe of schedule 40, nominal diameter 200 mm with different ANSI Flanges of class number

  • determination of load capacity of a nongasketed Flange Joint under combined internal pressure axial and bending loading for safe strength and sealing
    Journal of The Brazilian Society of Mechanical Sciences and Engineering, 2014
    Co-Authors: Muhammad Abid, Abdul Waheed Awan, David Nash
    Abstract:

    Performance of a bolted Flange Joint is characterized mainly due to its ‘strength’ and ‘sealing capability’. A number of analytical and experimental studies have been conducted to study these characteristics only under internal pressure loading. A very limited work is found in literature under combined internal pressure and bending loading. Due to the ignorance of external loads i.e. bending and axial in addition to the internal pressure loading, an optimized performance of the bolted Flange Joint can not be achieved. The present design codes do not address the effects of combined loading on the structural integrity and sealing ability. To investigate Joint strength and sealing capability under combined loading, an extensive comparative experimental and numerical study of a non-gasketed Flange Joint with two different taper angles on the Flange surface and with different load combinations is carried out and overall Joint performance and behavior is discussed. Actual Joint load capacity is determined under both the design and proof test pressures with maximum additional external loading (axial and bending) that can be applied for safe Joint performance.

  • the effect of bolt tightening methods and sequence on the performance of gasketed bolted Flange Joint assembly
    Structural Engineering and Mechanics, 2013
    Co-Authors: Muhammad Abid, Yasir Mehmood Khan
    Abstract:

    This paper presents results of the effect of different bolt tightening sequences and methods on the performance of gasketed bolted Flange Joint using nonlinear finite element analysis. Bolt preload scatter due to elastic interactions, Flange stress variation and bolt bending due to Flange rotation and gasket contact stress variation is difficult to eliminate in torque control method i.e. tightening one bolt at a time. Although stretch control method (tightening more than one bolt at time) eradicates the bolt preload scatter, Flange stress variation is relatively high. Flange Joint`s performance is compared to establish relative merits and demerits of both the methods and different bolt tightening sequences.

  • gasketed bolted Flange Joint s relaxation behaviour under different bolt up strategy
    Proceedings of the Institution of Mechanical Engineers Part E: Journal of Process Mechanical Engineering, 2009
    Co-Authors: K A Khan, Muhammad Abid, J A Chattha
    Abstract:

    Performance of a bolted Flange Joint is characterized mainly by its 'strength' and 'sealing capability'. Sealing capability of a bolted Flange Joint is highly dependent on the bolt up strategy during assembly because gasket stress distribution achieved during assembly process is the prime parameter. Any improper bolt up practice may result in the leakage from the Joint. In this article, two different bolt up strategies used in the industries during the assembly of a bolted Flanged Joint are used and Joints relaxation, gasket stress variation, and Joint's strength are analysed using detailed non-linear finite-element analysis.

  • bolt preload scatter and relaxation behaviour during tightening a 4 in 900 Flange Joint with spiral wound gasket
    Proceedings of the Institution of Mechanical Engineers Part E: Journal of Process Mechanical Engineering, 2008
    Co-Authors: Muhammad Abid, Saad Hussain
    Abstract:

    Gasketed bolted Flange pipe Joints are found prone to leakage during operating conditions. Therefore, performance of a gasketed Flange Joint is highly dependent on the proper Joint assembly with proper gasket, proper gasket seating stress, and proper preloading in the bolts of a Joint. For a gasketed Flange Joint, the two main concerns are the Joint strength and the sealing capability. To investigate these, a detailed three-dimensional non-linear finite-element analysis (FEA) of a gasketed Joint is carried out using a spiral wound gasket. FEA results are compared with the experimental results and are found to be in good agreement, hence validating the FE model developed. Bolt scatter, bolt bending, and bolt relaxation are considered to be the main factors affecting the Joint performance. In addition, the importance of proper bolt tightening sequence and number of passes and the influence of elastic and elasto-plastic material modelling on Joint performance are also presented. Stress variation in the Flange due to Flange rotation highlighted Joint strength, and gasket contact/seating stress variation highlighted the sealing performance during bolt up. Modelling the non-linearity of the spiral wound gasket using non-linear elements highlights reduced Joint strength and sealing performance. Summarizing, a dynamic mode in a gasketed Joint is concluded, which is the main reason for its failure.

玉井 宏章 - One of the best experts on this subject based on the ideXlab platform.

  • Cyclic loading test of High-strength Beam Joint by Use of Half-moon Shaped Bearing Bolts
    Graduate School of Engineering Nagasaki University, 2017
    Co-Authors: 玉井 宏章, 森田 真理乃, 島田 有二朗
    Abstract:

    We present the shear Joint using half-moon shaped bearing bolt as an effective fastener between high-strength steel members. Experimental studies were carried out to clarify the maximum strength and the elastic stiffness of beam Flange Joint. Also, materially and geometrically non-linear finite element analyses were carried out to show the mechanical properties of the Joint with half-moon shaped bearing bolts. This paper shows the concept and capabilities of presented bolts. Obtained result was summarized as follows. The shank of the half-moon-shaped bolt has enough ultimate strength. Slip back phenomena, in which the diagonal cut face of the shank slips out of its normal position, doesn’t occur during elastic cyclic loading. The half moon bolts always penetrate the connected steel plate so as to fill up a hole. Hence, the present beam Joint maintains constant stiffness during elastic cyclic loading

  • Fundamental Mechanical Properties of Joint using Half-Moon-Shaped Bearing Bolt
    Graduate School of Engineering Nagasaki University, 2015
    Co-Authors: 玉井 宏章, 桐山 尚大, 山下 祥平, 中島 康太
    Abstract:

    We present the shear Joint using half-moon-shaped bearing bolt as an effective fastener between high-strength steel members. Experimental studies were carried out to clarify the maximum strength of the bolted Joint and the elastic stiffness of beam Flange Joint. Also, materially and geometrically non-linear finite element analyses were carried out to show the mechanical properties of the Joint with half-moon shaped bearing bolts. This paper shows the concept and capabilities of presented bolts. Obtained result was summarized as follows. The shank of the half-moon-shaped bolt has enough ultimate strength: 0.9 times the shear strength of effective sectional area. Slip back phenomena, in which the diagonal cut face of the shank slipsout of its normal position, doesn't occur during large shear forceson the bolts. The half moon bolts always penetrate the connected steel plate so as to fill up a hole. Hence, the present shear Joint maintains constant stiffness during a large number of pulsating cyclic loadings

  • A New Fastener using Half-Moon Shaped Bolts for High-Strength Steel Member Part 6 Cyclic Loading Test on Beam Joint using Half-Moon-Shaped Bolt for High Strength members
    Graduate School of Engineering Nagasaki University, 2015
    Co-Authors: 玉井 宏章, 桐山 尚大, 山下 祥平, 中島 康太
    Abstract:

    We present the beamJoint using half-moon-shaped bearing bolt as an effective fastener between high-strength steel members. Experimental studies were carried out to clarify the elastic stiffness of beam Flange Joint. This paper shows capabilities of presented bolts. Obtained result was summarized as follows. In cyclic loading , the half-moon-shaped bolt to has sufficient flexural rigidity with the same that of as ordinary friction. Also, the half-moon-shaped bolts always penetrate the connected steel platesso as to fill up a hole. Hence, the present beam Joint maintains constant stiffness under a large number of pulsating cyclic loadings

中島 康太 - One of the best experts on this subject based on the ideXlab platform.

  • Fundamental Mechanical Properties of Joint using Half-Moon-Shaped Bearing Bolt
    Graduate School of Engineering Nagasaki University, 2015
    Co-Authors: 玉井 宏章, 桐山 尚大, 山下 祥平, 中島 康太
    Abstract:

    We present the shear Joint using half-moon-shaped bearing bolt as an effective fastener between high-strength steel members. Experimental studies were carried out to clarify the maximum strength of the bolted Joint and the elastic stiffness of beam Flange Joint. Also, materially and geometrically non-linear finite element analyses were carried out to show the mechanical properties of the Joint with half-moon shaped bearing bolts. This paper shows the concept and capabilities of presented bolts. Obtained result was summarized as follows. The shank of the half-moon-shaped bolt has enough ultimate strength: 0.9 times the shear strength of effective sectional area. Slip back phenomena, in which the diagonal cut face of the shank slipsout of its normal position, doesn't occur during large shear forceson the bolts. The half moon bolts always penetrate the connected steel plate so as to fill up a hole. Hence, the present shear Joint maintains constant stiffness during a large number of pulsating cyclic loadings

  • A New Fastener using Half-Moon Shaped Bolts for High-Strength Steel Member Part 6 Cyclic Loading Test on Beam Joint using Half-Moon-Shaped Bolt for High Strength members
    Graduate School of Engineering Nagasaki University, 2015
    Co-Authors: 玉井 宏章, 桐山 尚大, 山下 祥平, 中島 康太
    Abstract:

    We present the beamJoint using half-moon-shaped bearing bolt as an effective fastener between high-strength steel members. Experimental studies were carried out to clarify the elastic stiffness of beam Flange Joint. This paper shows capabilities of presented bolts. Obtained result was summarized as follows. In cyclic loading , the half-moon-shaped bolt to has sufficient flexural rigidity with the same that of as ordinary friction. Also, the half-moon-shaped bolts always penetrate the connected steel platesso as to fill up a hole. Hence, the present beam Joint maintains constant stiffness under a large number of pulsating cyclic loadings

David Nash - One of the best experts on this subject based on the ideXlab platform.

  • determination of load capacity of a nongasketed Flange Joint under combined internal pressure axial and bending loading for safe strength and sealing
    Journal of The Brazilian Society of Mechanical Sciences and Engineering, 2014
    Co-Authors: Muhammad Abid, Abdul Waheed Awan, David Nash
    Abstract:

    Performance of a bolted Flange Joint is characterized mainly due to its ‘strength’ and ‘sealing capability’. A number of analytical and experimental studies have been conducted to study these characteristics only under internal pressure loading. A very limited work is found in literature under combined internal pressure and bending loading. Due to the ignorance of external loads i.e. bending and axial in addition to the internal pressure loading, an optimized performance of the bolted Flange Joint can not be achieved. The present design codes do not address the effects of combined loading on the structural integrity and sealing ability. To investigate Joint strength and sealing capability under combined loading, an extensive comparative experimental and numerical study of a non-gasketed Flange Joint with two different taper angles on the Flange surface and with different load combinations is carried out and overall Joint performance and behavior is discussed. Actual Joint load capacity is determined under both the design and proof test pressures with maximum additional external loading (axial and bending) that can be applied for safe Joint performance.

  • structural strength gasketed vs non gasketed Flange Joint under bolt up and operating condition
    International Journal of Solids and Structures, 2006
    Co-Authors: Muhammad Abid, David Nash
    Abstract:

    This paper presents results of an experimental study of the behaviour of the stress variation at the Flange of a gasketed and non-gasketed Flanged pipe Joints during both the bolt up (pre-loading) and operating (internal pressure loading) conditions. Stress variations showing Flange yielding, Flange rotation, effects of Joint tightening sequence, identification of the mode of response to loading (static or dynamic) is discussed. In addition the effects of re-tightening, importance of high quality bolting with proper surface treatment and use of proper tooling are also discussed.

  • comparative study of the behaviour of conventional gasketed and compact non gasketed Flanged pipe Joints under bolt up and operating conditions
    International Journal of Pressure Vessels and Piping, 2003
    Co-Authors: Muhammad Abid, David Nash
    Abstract:

    Bolted Flanged Joints comprise an assembly of a number of important individual components, which are required to perform well together in service. The ideal requirement for a bolted Flange Joint is a 'zero-leak' condition. However, whilst recommended design procedures for bolted Flange Joints are available in international codes and standards, leakage problems are still faced by industry. These are common in both normal operating (internal pressure loading) and critical event conditions. The drive is, therefore, to find a Flange Joint assembly, which provides 'zero-leak condition' and requires little or no maintenance and handling. Considerable investigation in the area of optimised bolted Joints has been in progress for the past 10 years comparing traditional gasketed Joints and 'compact non-gasketed' Joints, using both analytical and experimental approaches. In this present study, two-dimensional non-linear finite element studies have been performed for both gasketed and non-gasketed bolted Flange pipe Joints. Based on the stress results for the Flange and the bolt and the Flange rotation/displacement, compact non-gasketed Flange Joints are shown to be a viable and preferable alternative to the conventional gasketed Flange Joints. Recommendations are made for a best-fit Flange model for static load conditions with 'zero-leak' sealing in a Flange Joint.

R A Mufti - One of the best experts on this subject based on the ideXlab platform.

  • prediction of welding distortions and residual stresses in a pipe Flange Joint using the finite element technique
    Modelling and Simulation in Materials Science and Engineering, 2005
    Co-Authors: Muhammad Abid, M. Siddique, R A Mufti
    Abstract:

    This paper presents a comparative study of three- and two-dimensional axisymmetric finite element (FE) analyses of a welded pipe–Flange Joint for residual stresses and deformations in order to identify their merits or demerits. Sequentially coupled thermal stress analysis is performed to simulate single pass metal inert gas welding. Butt weld geometry with a single 'V' for a 100 mm nominal diameter pipe and same sized weld neck type ANSI class #300 Flange is used. The heat input is modelled by using the Goldak double ellipsoidal heat source model. Temperature dependent material properties are used and deposition of filler metal is obtained by element birth and death feature. Both thermal and structural FE models are validated with experimental measurements. Residual stresses predicted by two-dimensional model are generally on the higher side and hence more conservative. However, we conclude that the three-dimensional FE model is preferable for the prediction of Flange face distortion since it is a vital parameter for Flange Joint performance.