scholarly journals RESIDUAL LIFE ASSESSMENT OF 40TPH CFBC BOILER THROUGH DIFFERENT NON-DESTRUCTIVE TESTING TECHNIQUESIN THERMAL POWER STATION

Author(s):  
Ju Ding ◽  
Min Zhang ◽  
Shu-hong Liu ◽  
Chen-huai Tang ◽  
Xu-chen Zhu ◽  
...  

Abstract This paper discusses four different ultrasonic guided wave standards. Three of them are China’s national standards or industry standards: GB/T 31211-2014 “Nondestructive Testing Ultrasound Guided Wave Detection”, GB/T 28704-2012“Non-destructive testing—Test method for ultrasonic guided wave testing based on magnetostrictive effects”, and DL/T 1452-2015 “Thermal Power Pipeline Ultrasound Guided Wave Detection”. The another one is ASTM E2929:“Standard Practice for Guided Wave Testing of Above Ground Steel Piping with Magnetostrictive Transfusion”. Through six aspects in this article, including testing application scope, preliminary requirements, standard specimen and comparative specimen, distant amplitude curve and time gain curve, the existing difference between China and America is obvious and diversity. It is necessary to explore the underlying reasons for the connection of Chinese code and international code in the field of Non-destructive testing. During the standardization, anyone of the standard should be actually compared on the presentation of chart, and the verification and comparison of results, and lists the similarities and differences of each part based on GB31211. This paper provides reference for China to integrate with foreign standards in the field of ultrasonic guided wave detection of pressure vessel and pipelines.


2016 ◽  
Vol 879 ◽  
pp. 1841-1846 ◽  
Author(s):  
Peter Starke ◽  
Hao Ran Wu ◽  
Christian Boller

The comprehensive characterization of the change in metallic materials’ microstructure due to an applied load is of prime importance for the understanding of basic fatigue mechanisms or more general damage evolution processes. If those mechanisms and processes are to be understood to a much greater extent, advanced fatigue life calculation methods being far away from linear damage accumulation models, have to be realized providing more than “classic fatigue data” only. Among others the PHYBAL (physically based fatigue life calculation) method including current enhancements and a thereon-based development named SteBLife (step-bar fatigue life approach) have been developed over the last 10 years. These methods allow the efforts in experimentation to be reduced by more than 90 % and therefore offer the possibility to take further fatigue relevant parameters into account. This therefore allows a variety of S,N-curves dependent on those fatigue relevant parameters to be generated with those methods easily establishing a multidimensional dataset. To just name a few examples of those parameters such as the influence of temperature, loading conditions, geometry as well as thermal and mechanical ageing processes on the fatigue behavior can now be calculated in accordance to a process being straightforward leading to an important step with regard to improving the efficiency of assessing structural components. Consequently, safety factors can be defined more in accordance to structural needs, being of highest interest with respect to the increasing number of ageing infrastructure such as highways, bridges or others. A lot of this ageing infrastructure has a strong need to be managed with respect to its structural integrity and the engineering community therefore tries the residual life of this infrastructure to be determined as appropriate as possible. In that context non-destructive testing parameters are increasingly considered to characterize a metallic material’s microstructure allowing more precise information to be obtained regarding the actual damage condition and the integrity of a component. The paper will address the high capability of non-destructive testing techniques for the evaluation of damage evolution processes also with respect to mechanism based fatigue as well as residual life calculations according to PHYBAL and SteBLife.


2017 ◽  
Vol 18 (2) ◽  
pp. 515-523 ◽  
Author(s):  
Lei Shi ◽  
Jaime Valls Miro

Abstract This work proposes a sampling inspection framework for point measurement non-destructive testing of pipelines to improve its time and cost efficiencies. Remaining pipe wall thickness data from limited dense inspection are modelled with spatial statistics approaches. The spatial dependence in the available data and some subjective requirements provide a reference for selecting a most efficient sampling inspection scheme. With the learned model and the selected sampling scheme, the effort of inspecting the residual part of the same pipeline or cohort will be significantly reduced from dense inspection to sampling inspection, and the full information can be reconstructed from samples while maintaining a reasonable accuracy. The recovered thickness map can be used as an equivalent measure to the dense inspection for subsequent structural analysis for failure risk estimation or remaining life assessment.


Author(s):  
Ashok Koul ◽  
Ajay Tiku ◽  
Karan Khullar ◽  
Jun Zhao

The results of a prognostics case study on GE Frame 5001P first stage turbine disc are presented in this paper. Currently used and promoted practices for metallurgical analysis such as hardness testing and replica based microstructural assessment and inspection of rotors for dimensional checks and cracks are not sufficient to ensure safety and reliability of the engine. The uncertainly of all engine variables including operational environment must be considered prior to returning the engine to service. It is required to accurately predict the temperature profile of the discs that can have serious consequences on the residual life assessment of the fracture prone rotors. The safe inspection interval (SII) determination of the design life expired engines and defining non-destructive inspection (NDI) sensitivity requirements for continued safe operation of the engine are equally important.


2021 ◽  
pp. 80-87
Author(s):  
T. G. Galieva ◽  
◽  
D. A. Ivanov ◽  
M. F. Sadykov ◽  
A. V. Golenishchev-Kutuzov ◽  
...  

Measurement of partial discharges (PD) is a generally accepted method of diagnosing the insulation of electrical equipment worldwide. Today, the trend is to move from conventional offline testing to online monitoring to predict the service life of insulation. For testing and calibration of the developed new methods with the contact method, a laboratory stand has been developed in accordance with GOST R 55191-2012 (IEC 60270:2000). The article suggests the use of acoustic and electromagnetic methods for a system of continuous non-contact non-destructive testing of the technical condition of insulation equipment, which will allow monitoring insulation equipment online and predicting its residual life. On their basis, a system of «on-line» diagnostics of high-voltage insulators has been developed.


Author(s):  
Jan Willem Noteboom

Stress corrosion cracking (SCC) in retaining rings of generators has been a major issue since large generator manufactures started to advise generator owners to replace and inspect retaining rings made from certain materials in the mid 1990’s. KEMA has been inspecting generator retaining rings with automated systems from the seventies on. Since 1995 new developments led to the possibility of also testing rings in situ, eliminating the need of removing the rotor from the stator and thus saving considerable down-time. Over the years, step by step improvements to the system and its application to generator retaining ring inspections have been implemented, one of which is the use of smaller probes and manipulators. Another improvement is the implementation of eddy current testing (ECT) to increase the detection capability for cracking at the outside surface in parallel to the automated ultrasonic testing (AUT). Experience obtained with this method contradicts some of the common ideas about reliability of other Non-destructive testing (NDT) methods, in particular the application of Dye Penetrant inspection (DPI) which appears to be less reliable. By performing fracture mechanics calculations to evaluate detected and sized flaw indications, predictions of remaining life of the rings can be made (Fitness-for-Purpose analysis). This paper presents results of applying the in situ retaining ring inspection system in the last 14 years and gives an overview of cases — some of those from recent inspections — where defect indications were detected, sized and evaluated. In some cases this resulted in recommendations to replace the retaining rings.


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