Mechanical Analysis and Safety Evaluation of Double-Packer String in a Horizontal Well

2013 ◽

Author(s):

Rui Liu ◽

Tie-ping Li ◽

Ming-yu Wang

Keyword(s):

High Pressure ◽

Nuclear Power ◽

Nuclear Reactor ◽

Safety Evaluation ◽

Practical Method ◽

Mechanical Analysis ◽

Power Equipment ◽

Pipe System ◽

Finite Element Software ◽

Class 1

In recent years, nuclear pipes play a very important role in the nuclear power equipment. Nuclear pipes especially class 1 usually contain cooling coolant of high temperature and high pressure in the operating nuclear power plant. The integrality of the nuclear pipes is very important to the nuclear reactor. This paper discusses the mechanical analysis and fatigue analysis of Class 1 pipes using finite element software. The soft ware PIPESTRESS is used to analysis the Class 1 pipe system to introduce the procedure for mechanical analysis and safety evaluation. The objective is to satisfy the criteria RCC-M. The results show that the pipe can guarantee the integrity of the pipe under the conditions. The method introduced in this paper can be used as a practical method for mechanical analysis of a nuclear Class 1 pipes.

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TREQ: Fuel Rod Performance Code for Demanding PWR Plants

Volume 5: Fuel Cycle and High and Low Level Waste Management and Decommissioning; Computational Fluid Dynamics (CFD), Neutronics Methods and Coupled Codes; Instrumentation and Control ◽

10.1115/icone17-75832 ◽

2009 ◽

Author(s):

I. Pastor ◽

N. Doncel

Keyword(s):

Fuel Cycle ◽

Safety Evaluation ◽

Mechanical Analysis ◽

Physical Models ◽

Principal Characteristics ◽

Strategy Of Development ◽

Fuel Rod ◽

Safety Margins ◽

Wide Range ◽

Thermal Mechanical Analysis

The search for improvements in nuclear fuel cycle economics results in increasing demands for fuel operation, including higher discharged burnup, and plant manoeuvrability. To achieve these objectives without a reduction of safety margins, new fuel designs and materials that enable enhanced performance capabilities have been developed like the dopped pellets products or the new cladding materials. Besides, fuel rod performance code are incorporating the experience gained in these irradiation conditions. In these regards, the European Fuel Group (EFG) has developed the TREQ code. TREQ is a fuel rod thermal-mechanical code used for the design and safety evaluation of fuel rods for PWR reactors. TREQ benefits from more than 30 year experience coming from the PAD code. The TREQ development was started by Westinghouse, BNFL and ENUSA, the EFG and it is primarily applied to the thermal-mechanical analysis of rods operating at steady-state or slow transient operations as well as to provide fuel inputs, for other codes used in the accident analyses and it has been validated over a wide range of irradiation conditions. Thus, TREQ Fuel Rod Performance Code meets customers’ needs taking advantage of the performance of new products. The code comprises physical models which are developed on the basis of both theoretical considerations and experimental or in-pile data. The physical models of the code apply to Zircaloy-4 and ZIRLO cladding rods containing uranium and gadolinia doped pellets, fabricated according to ENUSA/Westinghouse specification. TREQ code has been licensed in Belgium up to a rod average burnup over 70 MWd/kgU for application on fuel rod design for PWR reactors. Besides, the code has been used to support several LOCA analyses in Belgium and other European countries. In Spain, TREQ was used in the licensing process of the high rod burnup programs. At present, EFG participates in several Research and Development (R&D) programs. The data at extended rod burnup, higher power and higher fuel densities, from theses programs will be incorporated to update models or reduce uncertainties. This paper presents the principal characteristics of the code, the main mechanical models and the strategy of development for the future.

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Mechanical Analysis of Fracturing String with Double Packers in Horizontal Well

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.325-326.800 ◽

2013 ◽

Vol 325-326 ◽

pp. 800-803

Author(s):

Zhi Miao Li ◽

Qian Bei Yue ◽

Ju Bao Liu

Keyword(s):

Horizontal Well ◽

Reaction Force ◽

Frictional Resistance ◽

Mechanical Analysis ◽

Contact Friction ◽

Curvature Effect ◽

Technical Problems ◽

Precise Calculation ◽

Gap Element ◽

Space Beam Element

The design and mechanical analysis of fracturing string was one of the key technical problems in fracturing operation. Considering contact friction and curvature effect, contact nonlinear problem of fracturing string was solved by space beam element and multidirectional contact gap element method. Contact state, contact reaction force and corresponding frictional resistance between the fracturing string and borehole or inside casing wall could be accurately described by gap element, which generated less simplification in the mechanical model and more precise calculation of force and deformation. The calculations of field examples has shown that while the distance is 10 m, 20 m or 30 m between two packers of fracturing string, maximum axial sliding displacement of the first packer is 0.19 mm and sliding displacement of the second packer is 11.17mm, 23.78mm , or 36.46 mm. The theory basis is provided for the decision of reasonable distance between two packers.

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Mechanical Analysis and Strength Evaluation of KEY COMPONENTS Tripod of SNUBBING UNIT

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.477-478.303 ◽

2013 ◽

Vol 477-478 ◽

pp. 303-306

Author(s):

Min Luo ◽

Fa Cheng Li ◽

Ting Ting Zhao ◽

Ting Ting Xu ◽

Jiu Bao Liu ◽

...

Keyword(s):

Finite Element ◽

Evaluation Method ◽

Complex Structure ◽

Three Dimensional ◽

Safety Evaluation ◽

Mechanical Analysis ◽

Analysis Model ◽

Element Analysis ◽

Strength Evaluation ◽

Three Dimensional Finite Element

Tripod is the key components of snubbing unit, its strength directly affect the normal work of snubbing unit. Considering the structure and force characteristics of key components tripod of snubbing unit, three-dimensional finite element analysis model of tripod is established. By using the finite element method, mechanical analysis of tripod is conducted and safety evaluation is finished by adopting the stress classification and introducing analysis design standard of pressure vessel. The results show that key components tripod of snubbing unit are safe and reliable under the maximum lifting force and the maximum downward force. It provides theory evidence for snubbing unit design. The safety evaluation method provides effective evaluation methods for complex structure strength evaluation.

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Accident Safety Evaluation Method for Spent Fuel Dry Storage Facilities

Volume 7: Fuel Cycle, Decontamination and Decommissioning, Radiation Protection, Shielding, and Waste Management; Mitigation Strategies for Beyond Design Basis Events ◽

10.1115/icone25-66508 ◽

2017 ◽

Author(s):

Zhang Yubin ◽

Ouyang Yong ◽

Zhou Yuwei ◽

Liu Jinlin

Keyword(s):

Nuclear Power ◽

Evaluation Method ◽

Safety Evaluation ◽

Heat Removal ◽

Mechanical Analysis ◽

Spent Fuel ◽

Dry Storage ◽

Accident Condition ◽

Design Characteristics ◽

Storage Facilities

Dry storage is one of the ways to store spent fuel in the middle of the reactor, which can effectively alleviate the pressure of the storage on the spent fuel pool of nuclear power plant. This paper tries to combine the site of dry storage facilities and the design characteristics to explain and discuss the safety evaluation method under the accident condition, from the mechanical analysis, critical safety, the decay heat removal, the shielding design and so on. Then according to the operating procedures and the accident condition that may be occurred, put forward some possible ways of monitoring and measures of safety protection should be added.

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Light-cured dental composites characterization by Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100175272 ◽

1990 ◽

Vol 48 (4) ◽

pp. 428-429

Author(s):

B. M. Culbertson ◽

M. L. Devinev ◽

E. C. Kao

Keyword(s):

Electron Microscopy ◽

Mechanical Analysis ◽

Service Performance ◽

Dental Composite ◽

Dental Composites ◽

Neat Resin ◽

Scanning Calorimetry ◽

Research Meeting ◽

Formulation Variables

The service performance of current dental composite materials, such as anterior and posterior restoratives and/or veneer cements, needs to be improved. As part of a comprehensive effort to find ways to improve such materials, we have launched a broad spectrum study of the physicochemical and mechanical properties of photopolymerizable or visible light cured (VLC) dental composites. The commercially available VLC materials being studied are shown in Table 1. A generic or neat resin VLC system is also being characterized by SEM and TEM, to more fully understand formulation variables and their effects on properties.At a recent dental research meeting, we reported on the differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) characterization of the materials in Table 1. It was shown by DSC and DMA that the materials are substantially undercured by commonly used VLC techniques. Post curing in an oral cavity or a dry environment at 37 to 50°C for 7 or more hours substantially enhances the cure of the materials.

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