The Finite Element Analysis of the Large-Diameter Composite Slurry Valve Gate

2014 ◽  
Vol 989-994 ◽  
pp. 3149-3152
Author(s):  
Jie Wu ◽  
Zhao Meng Yang ◽  
Dong Zheng Wang

In a long distance slurry pipeline transport system, pulp valve plays a vital role, which combined the pulp valve application is more, ram is one of the important components of composite slurry valve. This article mainly aims at gate has carried on the design and analysis, finite element modeling, and study the corresponding constraints, in the process of loading method, large diameter combination valve gate stress and strain distribution are obtained, combined with the optimization method and finite element analysis software for its structure optimization research, realize the lightweight of the gate. To reduces the manufacturing cost of the gate, as to provide theoretical basis for design.

Author(s):  
M. Rashid ◽  
S. Chen ◽  
L. E. Collins

Tensile testing on large diameter line pipe is generally done using strap samples obtained in the transverse to pipe axis (TPA) orientation of a pipe. The strap samples are then flattened and machined prior to testing. Although the standardized tensile testing is well documented, the variability in the reported TPA tensile properties of the same material tested within a lab or at different labs has always been an issue. Recent work conducted at EVRAZ NA research lab has identified flattening as the main source of the variability in reported yield strength (YS) values for line pipe. The lack of a standard procedure for flattening TPA strap samples is a major obstacle to obtaining consistent results. Therefore, the main objective of this current study was to establish a standardized flattening procedure for TPA strap samples. Both finite element analysis (FEA) and experimental approaches were adopted. Various flattening methods and fixtures were studied. Extensive flattening experiments were conducted on TPA samples from different line pipe products. Results showed that the spring back after flattening in a TPA sample is different for pipes with different gauge and grades. It was established that consistent flattening can be achieved using appropriate fixtures for differerent ranges of tubular products defined by grade, diameter and gauges. Evaluation of the flattening fixture designs and experimental results are discussed in this paper.


2020 ◽  
Vol 103 (3) ◽  
pp. 003685042093648
Author(s):  
Liansen Sha ◽  
Andi Lin ◽  
Xinqiao Zhao ◽  
Shaolong Kuang

Topology optimization is a widely used lightweight design method for structural design of the collaborative robot. In this article, a topology optimization method for the robot lightweight design is proposed based on finite element analysis of the assembly so as to get the minimized weight and to avoid the stress analysis distortion phenomenon that compared the conventional topology optimization method by adding equivalent confining forces at the analyzed part’s boundary. For this method, the stress and deformation of the robot’s parts are calculated based on the finite element analysis of the assembly model. Then, the structure of the parts is redesigned with the goal of minimized mass and the constraint of maximum displacement of the robot’s end by topology optimization. The proposed method has the advantages of a better lightweight effect compared with the conventional one, which is demonstrated by a simple two-linkage robot lightweight design. Finally, the method is applied on a 5 degree of freedom upper-limb exoskeleton robot for lightweight design. Results show that there is a 10.4% reduction of the mass compared with the conventional method.


2013 ◽  
Vol 690-693 ◽  
pp. 1945-1949
Author(s):  
Xue Qin Ling ◽  
Peng Fu ◽  
Wei Zhang ◽  
Yang Chen

Diaphragm chamber is the key component in fluid end of high pressure diaphragm pump for long distance pipeline transportation. Structural dimensions are the major factors affecting mechanical strength and manufacturing cost of diaphragm chamber. In this paper, diaphragm chamber was simulated by finite element analysis software ANSYS. Mechanical strength of diaphragm chamber was checked in the light of ASMEVIII-2. The structure of diaphragm chamber was modified for the purpose of extending service life and reducing production costs. The analysis results provide some theoretical guidance for research and development of diaphragm chambers and relevant products.


Author(s):  
Meisam Takalloozadeh ◽  
Krishnan Suresh

The objective of this paper is to demonstrate a topology optimization method subject to displacement and stress constraints. The method does not rely on pseudo-densities; instead it exploits the concept of topological level-set where ‘partial’ elements are avoided. Consequently: (1) the stresses are well-defined at all points within the evolving topology, and (2) the finite-element analysis is robust and efficient. Further, in the proposed method, a series of topologies of decreasing volume fractions are generated in a single optimization run. The method is illustrated through numerical experiments in 2D.


Author(s):  
Donald J. Florizone

Traditional design techniques result in excess material being required for ellipsoidal heads. The 2001 ASME Boiler and Pressure Vessel Code Section VIII Division 1, UG-32D and Section VIII Division 2, AD-204 limit the minimum design thickness of the heads. ASME Boiler and Pressure Vessel Code Case 2261 provides alternate equations that enable thinner head design thickness. VIII-2 Appendix 3 and 4 methods potentially could be used to further optimize the head thickness. All the equations in the code use one thickness for the entire head. On large diameter thin heads the center or spherical area is often thicker than the knuckle area due to the method of manufacture. Including this extra material in the design calculations results in an increase of the MAWP of large diameter thin heads. VIII-2, AD-200 of the code permits localized thinning in a circumferential band in a cylindrical shell. Applying these same rules to elliptical heads would permit thinning in the knuckle region as well. Engineers have powerful finite element analysis tools that can be used to accurately determine levels of plastic strain and plastic deformed shapes. It is proposed that VIII-2 Appendix 4 and 5 methods be permitted for the design of elliptical heads. Doing so would permit significant decreases in thickness requirements. Different methods of Plastic Finite Element Analysis (PFEA) are investigated. An analysis of a PVRC sponsored burst test is done to develop and verify the PFEA methods. Two designs based on measurements of actual vessels are analyzed to determine the maximum allowable working pressures (MAWP) for thick and thin heads with and without local thin regions. MAWP is determined by limit analysis, per VIII-2 4-136.3 and by two other proposed methods. Using Burst FEA, the calculated burst pressure is multiplied by a safety factor to obtain MAWP. Large deflection large strain elastic perfectly plastic limit analyses (LDLS EPP LL) method includes the beneficial effect of deformations when determining the maximum limit pressure. Elliptical heads become more spherical during deformation. The spherical shape has higher pressure restraining capabilities. An alternate design equation for elliptical heads based on the LDLS EPP LL calculations is also proposed.


2004 ◽  
Vol 126 (3) ◽  
pp. 399-403 ◽  
Author(s):  
Abdulmalik A. Alghamdi ◽  
Muhsen S. Al-Sannaa

This paper presents numerical results obtained using Finite Element Analysis (FEA) in studying large diameter welded neck steel flanges under different loading conditions. Obtained FEA results show the effect of the clamping pressure, internal pressure, axial end load, temperature effect, gasket elasticity modulus on the contact pressure between the gasket and the steel flange. As expected clamping pressure is a determinate factor for the sealing condition. Gasket material is another primary factor in designing flanged joints.


2021 ◽  
Vol 21 (12) ◽  
pp. 5906-5911
Author(s):  
Juan Zhang ◽  
Donghui Li ◽  
Bo Zhang

Bearings play a vital role in the operation of a two-axis system. Long-term bearing use inevitably produce bubbles and frictional damage. Therefore, the protection of bearings is critical for the stable operation of a two-axis system. In this study, a TiO2 nanofilm is used to physically protect a bearing. The discretization method is used to analyse the cavitation process. Cavitation primarily occurs on the front surface of the pad during bearing operation. A finite element analysis of a bearing pad coated and not coated with TiO2 nanofilms shows that TiO2 nanofilms can effectively absorb the cavitation force exerted on pads, thereby reducing inflicted damage. Moreover, the TiO2 nanofilm reduces the friction coefficient of the pad surface, promoting good bearing capacity of the bearing during rotation. The TiO2 nanofilm serves as a protective layer that improves the anti-wear and bearing performance of a two-axis system.


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