TOFD Automatic Ultrasonic Testing for Condition Monitoring of Coke Drums

2003 ◽  
Author(s):  
Jorge A. Penso ◽  
Robert Owen ◽  
Masaaki Oka
Keyword(s):  
Condition Monitoring ◽  
Ultrasonic Testing ◽  
Phased Array ◽  
Service Evaluation ◽  
Pressure Vessels ◽  
Inspection System ◽  
Delayed Coking ◽  
Advantages And Disadvantages ◽  
Mechanical Cycling ◽  
History Of

Cracking and bulging in welded and internally lined pressure vessels that work in thermal-mechanical cycling service have been well known problems in the petrochemical, power and nuclear industries. In spite of this problem has been studied during the last fifty years, published literature and industry surveys show that similar problems still occur nowadays. Typical examples of this problem are the coke drums in the delayed coking units refinery process. Delayed coking units are among the refinery units that have higher economical yields. To shut down these units represents a high negative economical impact in refinery operations. Also, the maintenance costs associated with repairs are commonly very high. Cracking and bulging occurrences in the coke drums, most often at the weld areas, characterize the history of the operation of delayed coking units. To anticipate through wall cracking in these coke drums, AUT (automatic ultrasonic testing); Dual TOFD (time of flight diffraction) and the Phased Array technique simultaneous inspection system was selected among other inspection techniques as a condition monitoring tool during an unit turnaround. The inspection methodology in combination with fracture mechanics was used to classify discontinuities as acceptable and non-acceptable. This indicated approach helped to optimize the workscope during the turnaround and establish guidelines for inspection and repair of the delayed coker unit. This work presents the different steps followed during the inspection and fitness for service evaluation. Also, this study shows advantages and disadvantages of the AUT-Phased Array technique.

Optimizing Probe Active Aperture for Phased Array Weld Inspections

2021 ◽  
Vol 79 (8) ◽  
pp. 797-804
Author(s):  
Anmol Birring
Keyword(s):  
Fracture Mechanics ◽  
Ultrasonic Testing ◽  
Phased Array ◽  
Pressure Vessels ◽  
Acceptance Criteria ◽  
Nondestructive Technique ◽  
Cross Sectional ◽  
Area Of Interest ◽  
Array Technology ◽  
Selection Of

Phased array ultrasonic testing (PAUT) has become a popular nondestructive technique for weld inspections in piping, pressure vessels, and other components such as turbines. This technique can be used both in manual and automated modes. PAUT is more attractive than conventional angle-beam ultrasonic testing (UT), as it sweeps the beam through a range of angles and presents a cross-sectional image of the area of interest. Other displays are also available depending on the software. Unlike traditional A-scan instruments, which require the reconstruction of B- and C-scan images from raster scanning, a phased array image is much simpler to produce from line scans and easier to interpret. Engineering codes have incorporated phased array technology and provide steps for standardization, scanning, and alternate acceptance criteria based on fracture mechanics. The basis of fracture mechanics is accurate defect sizing. There is, however, no guidance in codes and standards on the selection and setup of phased array probes for accurate sizing. Just like conventional probes, phased array probes have a beam spread that depends on the probe’s active aperture and frequency. Smaller phased array probes, when used for thicker sections, result in poor focusing, large beam spread, and poor discontinuity definition. This means low resolution and oversizing. Accurate sizing for fracture mechanics acceptance criteria requires probes with high resolution. In this paper, guidance is provided for the selection of phased array probes and setup parameters to improve resolution, definition, and sizing of discontinuities.

Application of Flexible Ultrasonic Phased Array Technique on Detection of Fillet Welds in Small-Diameter Pipe Holder

2017 ◽  
Author(s):  
Weican Guo ◽  
Cunjian Miao ◽  
Xingji Du ◽  
Min Wang ◽  
Junfang Xia
Keyword(s):  
Nondestructive Testing ◽  
Ultrasonic Testing ◽  
Phased Array ◽  
Coupling Effect ◽  
Ultrasonic Inspection ◽  
Technical Problem ◽  
Small Diameter ◽  
Pressure Vessels ◽  
Fillet Welds ◽  
Diameter Pipe

Fillet welds in small-diameter pipe socket of pressure vessels always have complicated structures and groove types, which make it easy to produce porosity, lack of fusion, incomplete penetration and other flaws during welding. Therefore, nondestructive testing is a significant and meaningful approach to ensure the quality of welding for pressure vessels’ safety. Ultrasonic testing is the main method for nondestructive testing of pipe fillet welds. However, it is difficult to distinguish between the interference wave and the flaw echo, or to recognize the defect signal, while utilizing conventional ultrasonic testing technology. Additionally, the coupling effect is bad for traditional rigid probe on the concave surface when the probe is inserted into the small-diameter pipe to do the inner scanning. To obtain a good coupling effect, flexible phased array technology was put forward, with a bendable probe made from flexible materials. The probe could be bent and inserted into the inner pipe for longitudinal wave scanning, giving a good matching with the inner wall and replacing the traditional rigid probe. Besides, it is more convenient to conduct the ultrasonic testing, and the focal law could be changed easily according to the curve shape of the inner pipe, without replacing the probe. Thus, scanning and dynamic focusing in multiple angles and directions can be carried out, and the position, distribution and size of the flaws could be displayed intuitively combined with real-time imaging technology. This technology is able to obtain better coupling and detecting effects and solve the technical problem for concave ultrasonic inspection of fillet welds.

Advanced Ultrasonic Techniques in Pipeline Girth Welds Examination

2003 ◽  
Author(s):  
Giuseppina Cataldo ◽  
Roberto Legori
Keyword(s):  
Standard Method ◽  
Ultrasonic Testing ◽  
Phased Array ◽  
Critical Assessment ◽  
Radiation Hazard ◽  
Inspection System ◽  
Chemical Waste ◽  
Philosophy Of Engineering ◽  
Ultrasonic Techniques ◽  
Girth Welds

Installation of pipelines onboard a lay-barge requires rapid inspection and judgement of all girth welds prior to leaving the vessel. Furthermore, the new philosophy of Engineering Critical Assessment (ECA) based on the principles of fracture mechanics to assess the severity of a defect on its vertical extent requires the application of an inspection system able to accurately assess height, length and through thickness location of the defect in order to reducing the number of unnecessary repairs. Automated Ultrasonic Testing (AUT) is rapidly replacing radiography as standard method of inspecting pipeline girth welds, reducing pipeline costs through increased productivity and avoiding the radiation hazard and the chemical waste of the film processing. This paper describes SAIPEM experience with the new Phased Array AUT technology carried out on several projects, particularly with reference to the ultra-deep water Blue Stream Project, which required an extensive qualification of the AUT System in accordance to DNV Rules [1,2].

An overview of Osmotic Drug Delivery System: An update review

2017 ◽  
Vol 6 (7) ◽  
pp. 5426 ◽  
Author(s):  
Hiren J. Patel ◽  
Vaishnavi P. Parikh
Keyword(s):  
Drug Delivery ◽  
Drug Delivery Systems ◽  
Life Cycle Management ◽  
Delivery Systems ◽  
Osmotic Pump ◽  
Factors Affecting ◽  
Advantages And Disadvantages ◽  
New Chemical Entities ◽  
History Of ◽  
Novel Drug

The pharmaceutical industry has faced several marked challenges in order to bring new chemical entities (NCEs) into the market over the past few decades. Various novel drug delivery approaches have been used as a part of life cycle management from which Osmotic drug delivery systems look the most promising one. After discussing the history of osmotic pump development, this article looks at the principles, advantages and disadvantages of osmotic drug delivery systems. Then, the basic components of osmotic pump and factors affecting the design of oral osmotic drug delivery systems are discussed in detail. In the later part of the manuscript, various types of osmotic pumps available in the market and evaluation methods for osmotic drug delivery systems are discussed in detail.

scholarly journals The Ocular Gene Delivery Landscape

Biomolecules ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1135
Author(s):  
Bhubanananda Sahu ◽  
Isha Chug ◽  
Hemant Khanna
Keyword(s):  
Gene Therapy ◽  
Genetic Diseases ◽  
Gene Therapies ◽  
Advantages And Disadvantages ◽  
Fda Approval ◽  
New Information ◽  
Efficient Delivery ◽  
Delivery Routes ◽  
History Of ◽  
Different Parts

The eye is at the forefront of developing therapies for genetic diseases. With the FDA approval of the first gene-therapy drug for a form of congenital blindness, numerous studies have been initiated to develop gene therapies for other forms of eye diseases. These examinations have revealed new information about the benefits as well as restrictions to using drug-delivery routes to the different parts of the eye. In this article, we will discuss a brief history of gene therapy and its importance to the eye and ocular delivery landscape that is currently being investigated, and provide insights into their advantages and disadvantages. Efficient delivery routes and vehicle are crucial for an effective, safe, and longer-lasting therapy.

MicroRNA annotation in plants: current status and challenges

2021 ◽  
Author(s):  
Yongxin Zhao ◽  
Zheng Kuang ◽  
Ying Wang ◽  
Lei Li ◽  
Xiaozeng Yang
Keyword(s):  
Small Rna ◽  
Signal To Noise Ratio ◽  
Current Status ◽  
Mirna Biogenesis ◽  
Plant Mirnas ◽  
Signal To Noise ◽  
Advantages And Disadvantages ◽  
Plant Mirna ◽  
History Of ◽  
Mirna Biogenesis Pathway

Abstract Last two decades, the studies on microRNAs (miRNAs) and the numbers of annotated miRNAs in plants and animals have surged. Herein, we reviewed the current progress and challenges of miRNA annotation in plants. Via the comparison of plant and animal miRNAs, we pinpointed out the difficulties on plant miRNA annotation and proposed potential solutions. In terms of recalling the history of methods and criteria in plant miRNA annotation, we detailed how the major progresses made and evolved. By collecting and categorizing bioinformatics tools for plant miRNA annotation, we surveyed their advantages and disadvantages, especially for ones with the principle of mimicking the miRNA biogenesis pathway by parsing deeply sequenced small RNA (sRNA) libraries. In addition, we summarized all available databases hosting plant miRNAs, and posted the potential optimization solutions such as how to increase the signal-to-noise ratio (SNR) in these databases. Finally, we discussed the challenges and perspectives of plant miRNA annotations, and indicated the possibilities offered by an all-in-one tool and platform according to the integration of artificial intelligence.

Advantages and disadvantages of main surgical approaches for robot-assisted radical prostatectomy

2020 ◽  
Vol 10 (4) ◽  
pp. 347-354
Author(s):  
Dmitriy M. Il’in ◽  
Vladimir A. Makeev
Keyword(s):  
Radical Prostatectomy ◽  
Abdominal Cavity ◽  
Prostate Gland ◽  
Clinical Situation ◽  
Surgical Approaches ◽  
Robot Assisted ◽  
Scientific Databases ◽  
Advantages And Disadvantages ◽  
Robotic Assisted Surgery ◽  
History Of

The introduction of robotic-assisted surgery into clinical practice has opened up new possibilities for the surgical treatment of urological patients. Robot-assisted radical prostatectomy (RARP) is one of the most commonly performed robot-assisted surgery. The review is devoted to the main surgical approaches for RARP. An analysis of publications on this topic was carried out using the search engines of the scientific databases PubMed, Medscape, Google Scholar, eLibrary when writing the article The article presents an overview of the advantages and disadvantages of the existing four access options for RARP: anterior, perineal, lateral and posterior, as well as oncological and functional outcomes of operations. It has been shown that a surgeon with different approaches can choose the most suitable one for a given clinical situation, focusing on the stage of the disease, the patients age, anatomical features of the prostate gland, the state of the patients erectile function, and the history of operations on the abdominal cavity and pelvic organs.

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