The Creep Measurement of 475°C Pipeline Using Moire Interferometry

1998 ◽  
Vol 120 (2) ◽  
pp. 144-148 ◽  
Author(s):  
X. Huimin ◽  
Z. Daqing ◽  
D. Fulong ◽  
Z. Wei ◽  
P. Dietz ◽  
...  

In this study, a new experimental method for measuring the creep of pipeline using moire interferometry was proposed. Curved-surface-deformed grating replicating technique was combined with the high-temperature-resistant grating and moire interferometry method, and was applied to measure the creep of a 475°C main steam pipeline in the Qinghe Power Plant for 3600 h. The measuring principle and experimental techniques are described. The measuring error and experimental results are discussed in detail.

2006 ◽  
Vol 306-308 ◽  
pp. 1037-1042 ◽  
Author(s):  
Hui Min Xie ◽  
Hang Shi ◽  
Peng Wan Chen ◽  
Feng Lei Huang ◽  
Dai Ning Fang

In this paper, the creep deformation of PBX was measured using the moiré interferometry. The experimental results show a different creep process compared with pure high polymer and this phenomenon is preliminary analyzed from damage mechanics.


2007 ◽  
Vol 7-8 ◽  
pp. 3-9 ◽  
Author(s):  
David Nowell

Fatigue crack closure is an important phenomenon which needs to be taken into account in the development of models for crack propagation. This paper presents an overview of techniques for measuring crack closure. The moiré interferometry approach is described in more detail and some experimental results are presented and compared with the predictions of closure models.


2013 ◽  
Vol 330 ◽  
pp. 549-552 ◽  
Author(s):  
J.H. Jia ◽  
H.C. Zhang ◽  
X.Y. Hu ◽  
L.P. Cai ◽  
S.T. Tu

The main challenge of long-time creep monitoring on site is a reliable sensor. In this paper, a sensing device is developed specifically for high temperature creep monitoring. And it is applied to on-line monitor the strain of material on T-joint of main steam piping. Its reliability is verified theoretically using the finite element method and experimentally by high temperature on site test. The creep damage of the T joint is evaluated basing on the creep rate sensed by the sensing device. And the residual life is predicted for the piping system using the Monkman-Grant equation. This system is useful for safety assessment procedures in thermal power plant, nuclear power plant and petrochemical industries.


2006 ◽  
Vol 326-328 ◽  
pp. 517-520 ◽  
Author(s):  
Jin Hyoung Park ◽  
Chang Kyu Chung ◽  
Kyoung Wook Paik ◽  
Soon Bok Lee

Among many factors that influence the reliability of a flip-chip assembly using NCF interconnections, the most effective parameters are often the coefficient of thermal expansion (CTE), the modulus (E), and the glass transition temperatures (Tg). Of these factors, the effect of Tg on thermal deformation and device reliability is significant; however, it has not been shown clearly what effect Tg has on the reliability of NCF. The Tg of a conventional NCF material is approximately 110°C. In this study, a new high Tg NCF material that has a 140oC Tg is proposed. The thermal behaviors of the conventional and new NCFs between -40oC to 150oC are observed using an optical method. Twyman-Green interferometry and the moiré interferometry method are used to measure the thermal micro-deformations. The Twyman-Green interferometry measurement technique is applied to verify the stress-free state. The stress-free temperatures of the conventional and new Tg NCF materials are approximately 100oC and 120oC respectively. A shear strain at a part of the NCF chip edge is measured by moiré interferometry. Additionally, a method to accurately measure the residual warpage and shear strain at room temperature is proposed. Through the analysis of the relationship between the warpage and the shear strain, the effect of the high-Tg NCF material on the reliability is studied.


2005 ◽  
Vol 295-296 ◽  
pp. 313-318
Author(s):  
S.R. Lee ◽  
Z.S. Luo ◽  
H.S. Chiou ◽  
B.G. Wang ◽  
L.S. Liu

With the development of modern engineering such as micro-electro-mechanical system (MEMS) and new material, the deformation measurement of 3D displacement field is required. Moiré interferometry has become common for measuring the deformations of two-dimension in-plane displacement field. To solve the problem of 3D displacement field, a system for measuring the deformations of 3D displacement field is designed. By using this system, we can measure the out-of-plane displacement by appending a set of electronic speckle interference system based on Moiré interferometry system. Adjusting the incident angle of the incident light, the transmitting direction of the first order diffracted wave in a Moiré interferometry system is assigned to deviate with a small angle from the vertical direction of the specimen surface. Thus the first order diffracted wave is separated from the place of the appended interference field. The striated patterns of the deformations of 3D displacement field can be obtained at the same time. These striated patterns are recorded respectively by three CCD cameras and are stored and processed by a computer. The synchronous measuring method brings certain amount of measuring errors into the measurement of in-plane displacement. This measuring error is analyzed in theory. When real-time measurement is not required, this system can be changed into another system in which the in-plane and the out-of-plane displacement field are measured by time sharing to reduce the measuring errors. The theoretical derivation and a part of experimental results for verification are presented.


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