Dharmveer Singh

The ever-changing market and evolving power sector poses a constant need for cost reduction and reducing atmospheric emissions. This has led to a worldwide impetus to improve the power plant efficiency thereby reducing emissions and improving cost effectiveness. This necessitate the requirement for materials with improved elevated temperature and high strength properties. These new and critical materials need the reliable NDE techniques which can provide more accurate flaw detection.
Among… عرض المزيد

The ever-changing market and evolving power sector poses a constant need for cost reduction and reducing atmospheric emissions. This has led to a worldwide impetus to improve the power plant efficiency thereby reducing emissions and improving cost effectiveness. This necessitate the requirement for materials with improved elevated temperature and high strength properties. These new and critical materials need the reliable NDE techniques which can provide more accurate flaw detection.
Among all non-destructive examination methods, Advanced Ultrasonic examinations (PAUT and TOFD) are some of the most reliable volumetric examinations along with conventional Ultrasonic Examination for the most used and advance materials. The change in microstructures of the materials affect acoustic properties of the material, resulting in change of attenuation, scattering, SNR etc. Heat treatment and mechanical work (cold or hot) modifies the microstructure of the material. This provides a correlation between heat treatment, mechanical work and responses from ultrasonic examination Ultrasonic testing suffers from some inherent drawbacks which can be correlated with the microstructure of the materials. Microstructural variations can cause varied ultrasonic response because of changes in attenuation, velocity, scattering, SNR. Further, it is well known that prior heat treatment and mechanical working also plays a key role in modifying microstructure of the material. Hence a correlation is often derived between the heat treatment and variation in ultrasonic response. Specimen was heat treated at different heat treatment cycles and this study was carried out to find the correlation between microstructural changes and acoustic responseof the material. Further investigation was done to improve the detectability from PAUT and TOFD. عرض أقل

With the advancement of technology and increase in competitive urge of industries there is an increasing need
of versatile, cost effective and more reliable volumetric NDT Techniques, leading to advanced techniques like
PAUT and TOFD in industrial applications.
PAUT is currently being used immensely in various sectors. TOFD has been emerged one of best technique for
accurate sizing with the limitation of surface and back surface detection. TOFD finds its application in… عرض المزيد

With the advancement of technology and increase in competitive urge of industries there is an increasing need
of versatile, cost effective and more reliable volumetric NDT Techniques, leading to advanced techniques like
PAUT and TOFD in industrial applications.
PAUT is currently being used immensely in various sectors. TOFD has been emerged one of best technique for
accurate sizing with the limitation of surface and back surface detection. TOFD finds its application in boiler
industry along with PAUT precisely because of the benefit of precise size measurement of flaws in addition to
higher POD and lower FCR compared to the conventional techniques.
This study provides a thorough understanding of the extent application of PAUT and TOFD in inspection of
pressure part joints of a boiler and the long-standing benefits of cost and time saving with much better
detectability, compared to other existing conventional volumetric NDT methods عرض أقل

This work is based on use of unique method of generation of guided waves based on the Magnetostrictive effect (Joule Effect) and inverse
Magnetostrictive effect (Villary Effect). This work provides and improves the defect detection capability of guided waves generated by
Magnetostrictive effect, in high temperature, cement coated pipes, rundown pipelines especially in refineries and power plants at different
conditions. MATLAB has been used as a tool for averaging the signals to… عرض المزيد

This work is based on use of unique method of generation of guided waves based on the Magnetostrictive effect (Joule Effect) and inverse
Magnetostrictive effect (Villary Effect). This work provides and improves the defect detection capability of guided waves generated by
Magnetostrictive effect, in high temperature, cement coated pipes, rundown pipelines especially in refineries and power plants at different
conditions. MATLAB has been used as a tool for averaging the signals to improve SNR (Signal to Noise Ratio).
This works enables to improve sensitivity and resolution. For specific purposes in oil and power sector industries, many pipes are coated with
the cement circumferentially either from inside or outside the pipe. To know the crack or working condition of cement coated pipelines guided
waves have been used for defect detection. عرض أقل

End plug is attached at each of the header end. Its design leaves about 3 mm overlap area, which remains un-fused at
the root through out the circumference of header, resulting in permanent indications in ultrasonic testing, and hence
uncertainty arises about where these indications are coming from. Theoretically no indication should come from the
overlap area and indications can come from the interface of weld and parent metal of end plug, providing great
difficulty in… عرض المزيد

End plug is attached at each of the header end. Its design leaves about 3 mm overlap area, which remains un-fused at
the root through out the circumference of header, resulting in permanent indications in ultrasonic testing, and hence
uncertainty arises about where these indications are coming from. Theoretically no indication should come from the
overlap area and indications can come from the interface of weld and parent metal of end plug, providing great
difficulty in interpretation if indications are from lack of sidewall fusion or from overlap area.
A mock-up block was prepared with sufficient SDHs for simulation of Lack of Side Wall Fusion, MPI and DP was
carried for confirmation of overlap area, etching to confirm distinction of weld, HAZ and parent metal, macro was
carried out to see the overlap area and then finally UT was carried out and with the simulation it was established that
the indications were coming from root indications are coming from the overlap area because of its configuration and
such indications should be disregarded عرض أقل

This work presents an analytical and numerical approach to a novel non-referential concept for the defect detection using Autocorrelation
in Frequency Modulated Thermal Wave Imaging. Mathematical equations have been derived for Autocorrelation which has further been verified
by MATLAB-SIMULINK simulation