Ultrasonic Phased Array: Detection of Detrimental Conditions in High-Density Polyethylene Butt-Fusion Joints

2010 ◽  
Author(s):  
Caleb J. Frederick
Keyword(s):  
High Density Polyethylene ◽  
Nuclear Power ◽  
Power Plants ◽  
Phased Array ◽  
Cold Fusion ◽  
High Density ◽  
Visual Examination ◽  
Full Spectrum ◽  
Ultrasonic Phased Array ◽  
Joint Integrity

Today, commercial nuclear power plants are installing High-Density Polyethylene (HDPE) in non-safety-related and safety-related applications. While this material has numerous advantages over the carbon steel pipes that historically have been used for the same applications, developing a way to accurately inspect for joint integrity in HDPE has become increasingly important to utilities and the U.S. Nuclear Regulatory Commission (USNRC). This paper will investigate the ability to quantify the levels of detection of flaws and detrimental conditions using ultrasonic phased array, in butt-fusion joints throughout the full spectrum of applicable HDPE pipe diameters and wall-thicknesses. Perhaps the most concerning joint condition is that of “Cold Fusion”. A cold-fused joint is created when molecules along the fusion line do not fully entangle or co-crystallize. Once the fusion process is complete, during visual examination, there is the appearance of a good quality joint. However, the joint does not have the strength needed, as the required co-crystallization along the pipe faces has not occurred. Performing a visual examination of the bead, as required by the current revision of ASME Code Case N-755, does not provide adequate guarantee of joint integrity. Therefore, volumetric examination is of special concern to the USNRC to safeguard against this type of detrimental condition. Factors addressed will include pipe diameter, wall-thickness, fusing temperature, interfacial pressure, dwell (open/close) time, and destructive verification of ultrasonic data.

Quantifying Detection Capabilities of Detrimental Conditions in High-Density Polyethylene Butt-Fusion Joints

2010 ◽  
Author(s):  
Caleb J. Frederick
Keyword(s):  
High Density Polyethylene ◽  
Nuclear Power ◽  
Power Plants ◽  
Cold Fusion ◽  
Nuclear Regulatory Commission ◽  
High Density ◽  
Full Spectrum ◽  
Asme Code ◽  
Regulatory Commission ◽  
Joint Integrity

Today, commercial nuclear power plants are installing High-Density Polyethylene (HDPE) piping in non-safety-related and safety-related systems. HDPE has been chosen in limited quantity to replace carbon steel piping as it does not support rust, rot, or biological growth. However, due to its relatively short nuclear service history, developing a way to accurately evaluate joint integrity in HDPE is crucial to utilities and the U.S. Nuclear Regulatory Commission (USNRC). This paper will investigate using ultrasonic Phased Array to quantify detection of flaws and detrimental conditions in butt-fusion joints throughout the full spectrum of applicable HDPE pipe diameters and wall-thicknesses. Currently the most concerning joint condition is that of “Cold Fusion”. A cold-fused joint is created when molecules along the fusion line do not fully entangle or co-crystallize. Once the fusion process is complete, there is the appearance of a good, quality joint. However, the fabricated joint does not have the required strength as the co-crystallization along the pipe faces has not occurred. Therefore, performing a visual examination of the bead, as required by the current revision of ASME Code Case N-755, does not provide adequate assurance of joint integrity. As a potential solution, volumetric examination is being considered by the USNRC to safeguard against this and other types of detrimental conditions. Factors addressed will include pipe diameter, wall-thickness, fusing temperature, interfacial pressure, dwell (open/close) time, and destructive correlation with ultrasonic data.

Evaluation of Ultrasonic Phased-Array for Detection of Planar Flaws in High-Density Polyethylene (HDPE) Butt-Fusion Joints

2016 ◽  
Author(s):  
Matthew S. Prowant ◽  
Kayte M. Denslow ◽  
Traci L. Moran ◽  
Richard E. Jacob ◽  
Trenton S. Hartman ◽  
...  
Keyword(s):  
High Density Polyethylene ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Phased Array ◽  
National Laboratory ◽  
Cooling Water ◽  
Pacific Northwest National Laboratory ◽  
Nuclear Regulatory Commission ◽  
High Density

The desire to use high-density polyethylene (HDPE) piping in buried Class 3 service and cooling water systems in nuclear power plants is primarily motivated by the material’s high resistance to corrosion relative to that of steel alloys. The rules for construction of Class 3 HDPE pressure piping systems were originally published as an alternative to the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME BPVC) in ASME Code Case N-755 and were recently incorporated into the ASME BPVC Section III as Mandatory Appendix XXVI (2015 Edition). The requirements for HDPE examination are guided by criteria developed for metal pipe and are based on industry-led HDPE research and conservative calculations. Before HDPE piping will be generically approved for use in U.S. nuclear power plants, the U.S. Nuclear Regulatory Commission (NRC) must have independent verification of industry-led research used to develop ASME BPVC rules for HDPE piping. With regard to examination, the reliability of volumetric inspection techniques in detecting fusion joint fabrication flaws against Code requirements needs to be confirmed. As such, confirmatory research was performed at the Pacific Northwest National Laboratory (PNNL) from 2012 to 2015 to assess the ability of phased-array ultrasonic testing (PAUT) as a nondestructive evaluation (NDE) technique to detect planar flaws, represented by implanted stainless steel discs, within HDPE thermal butt-fusion joints. All HDPE material used in this study was commercially dedicated, 305 mm (12.0 in.) nominal diameter, dimension ratio (DR) 11, PE4710 pipe manufactured with Code-conforming resins, and fused by a qualified and experienced operator. Thermal butt-fusion joints were fabricated in accordance with or intentionally outside the standard fusing procedure specified in ASME BPVC. The implanted disc diameters ranged from 0.8–2.2 mm (0.03–0.09 in.) and the post-fabrication positions of the discs within the fusion joints were verified using normal- and angled-incidence X-ray radiography. Ultrasonic volumetric examinations were performed with the weld beads intact and the PA-UT probes operating in the standard transmit-receive longitudinal (TRL) configuration. The effects of probe aperture on the ability to detect the discs were evaluated using 128-, 64-, and 32-element PA-UT probe configurations. Results of the examinations for each of the three apertures used in this study will be discussed and compared based on disc detection using standard amplitude-based signal analysis that would typically be used with the ultrasonic volumetric examination methods found in ASME BPVC.

High-Density Polyethylene Piping Butt-Fusion Joint Examination Using Ultrasonic Phased Array

2009 ◽  
Author(s):  
Caleb Frederick ◽  
Allen Porter ◽  
Dave Zimmerman
Keyword(s):  
High Density Polyethylene ◽  
Phased Array ◽  
Low Frequency ◽  
Cold Fusion ◽  
Probability Of Detection ◽  
High Density ◽  
Low Frequency Ultrasound ◽  
Ultrasonic Phased Array ◽  
Joint Examination ◽  
Automated Data Acquisition

With the increasing use of High-Density Polyethylene (HDPE) piping for nuclear applications, nondestructive evaluation is an important tool for evaluation of the integrity in fused joints. This paper will discuss the method of using Ultrasonic Phased Array for inspecting Butt-Fusion (BF) joints in HDPE piping. The benefit of Phased Array is the ability to perform a volumetric inspection using multiple angles which greatly increases the probability of detection of defects, and allows the data to be analyzed using a representative 2-dimentional image of the joint [1]. It has been determined that successfully producing BF joints is highly dependent on environmental and mating-surface conditions. The primary defects of concern are lack-of-fusion (LOF), an area of the joint where there is no bond [2], cold fusion (CF), an area of partial bond, and inclusion. Phased Array has successfully demonstrated the ability of detecting and characterizing these defects using low frequency ultrasound. Factors addressed include joint location, wall thickness, material temperature, transducer wedge material, and manual vs. automated data acquisition.

High-Density Polyethylene Piping Butt-Fusion Joint Examination Using Ultrasonic Phased Array

2010 ◽  
Vol 132 (5) ◽  
Author(s):  
Caleb Frederick ◽  
Allen Porter ◽  
David Zimmerman
Keyword(s):  
High Density Polyethylene ◽  
Phased Array ◽  
Low Frequency ◽  
Cold Fusion ◽  
Probability Of Detection ◽  
High Density ◽  
Two Dimensional Image ◽  
Low Frequency Ultrasound ◽  
Ultrasonic Phased Array ◽  
Joint Examination

With the increasing use of high-density polyethylene (HDPE) piping for nuclear applications, nondestructive evaluation is an important tool for evaluation of the integrity in fused joints. This paper will discuss the method of using ultrasonic phased array for inspecting butt-fusion (BF) joints in HDPE piping. The benefit of phased array is the ability to perform a volumetric inspection using multiple angles, which greatly increases the probability of detection of defects and allows the data to be analyzed using a representative two-dimensional image of the joint. It has been determined that successfully producing BF joints is highly dependent on environmental and mating-surface conditions. The primary defects of concern are lack-of-fusion, an area of the joint where there is no bond, cold fusion, an area of partial bond, and inclusion. Phased array has successfully demonstrated the ability of detecting and characterizing these defects using low frequency ultrasound. Factors addressed include joint location, wall thickness, material temperature, transducer wedge material, and manual versus automated data acquisition.

Ultrasonic Phased Array Examination of Butt-Fusion Joints in High-Density Polyethylene

2009 ◽  
Author(s):  
Caleb Frederick ◽  
Allen Porter ◽  
David Zimmerman
Keyword(s):  
High Density Polyethylene ◽  
Phased Array ◽  
Low Frequency ◽  
Cold Fusion ◽  
Probability Of Detection ◽  
High Density ◽  
Low Frequency Ultrasound ◽  
Ultrasonic Phased Array ◽  
Joint Location ◽  
Automated Data Acquisition

With the increasing use of High-Density Polyethylene (HDPE) piping for nuclear applications, nondestructive evaluation is an important tool for evaluation of the integrity in fused joints. This paper will discuss the method of using Ultrasonic Phased Array for inspecting Butt-Fusion (BF) joints in HDPE piping. The benefit of Phased Array is the ability to perform a volumetric inspection using multiple angles which greatly increases the probability of detection of defects, and allows the data to be analyzed using a representative 2-dimentional image of the joint [1]. It has been determined that successfully producing BF joints is highly dependent on environmental and mating-surface conditions. The primary defects of concern are lack-of-fusion (LOF), an area of the joint where there is no bond [2], cold fusion (CF), an area of partial bond, and inclusion. Phased Array has successfully demonstrated the ability of detecting and characterizing these defects using low frequency ultrasound. Factors addressed include joint location, wall thickness, material temperature, transducer wedge material, and manual vs. automated data acquisition.

Dynamic Testing of High Density Polyethylene Vent and Drain Configurations

2012 ◽  
Author(s):  
Douglas Munson ◽  
Timothy M. Adams ◽  
Shawn Nickholds
Keyword(s):  
Carbon Steel ◽  
High Density Polyethylene ◽  
Nuclear Power ◽  
Power Plants ◽  
Dynamic Testing ◽  
High Density ◽  
Steel Pipe ◽  
Labor Costs ◽  
Service Water ◽  
Hdpe Pipe

For corroded piping in low temperature systems, such as service water systems in nuclear power plants, replacement of carbon steel pipe with high density polyethylene (HDPE) pipe is a cost-effective solution. HDPE pipe can be installed at much lower labor costs than carbon steel pipe, and HDPE pipe has a much greater resistance to corrosion. This paper presents the results of the seismic testing of selected vent and drain configurations. This testing was conducted to provide proof of the conceptual design of HDPE vent and drain valve configurations. A total of eight representative models of HDPE vent and drain assemblies were designed. The models were subjected to seismic SQURTS spectral acceleration up to maximum shake table limits. The test configurations were then checked for leakage and operability of the valves. The results for these tests, along with the test configurations, are presented. Also presented are the acceleration data observed at various points on the test specimens.

Application of Ultrasonic Phased Array Techniques for Inspection of Stud Bolts in Nuclear Power Plants

2006 ◽  
Vol 110 ◽  
pp. 97-104 ◽  
Author(s):  
Sang Woo Choi ◽  
Joon Hyun Lee
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Phased Array ◽  
Nuclear Reactor ◽  
Fatigue Cracks ◽  
Ultrasonic Inspection ◽  
Phased Array Techniques ◽  
Ultrasonic Phased Array ◽  
Ultrasonic Images

The reactor vessel body and closure head are fastened with the stud bolt that is one of crucial parts for safety of the reactor vessels in nuclear power plants. It is reported that the stud bolt is often experienced by fatigue cracks initiated at threads. Stud bolts are inspected by the ultrasonic technique during the overhaul periodically for the prevention of failure which leads to radioactive leakage from the nuclear reactor. The conventional ultrasonic inspection for stud bolts was mainly conducted by reflected echo method based on shadow effect. However, in this technique, there were numerous spurious signals reflected from every oblique surfaces of the thread. In this study, ultrasonic phased array technique was applied to investigate detectability of flaws in stud bolts and characteristics of ultrasonic images corresponding to different scanning methods, that is, sector and linear scan. For this purpose, simplified stud bolt specimens with artificial defects of various depths were prepared.

Ultrasonic Evaluation of Inclusions and Surface-Breaking Defects in High Density Polyethylene (HDPE) Butt Fusion and Mitered Joints

2015 ◽  
Author(s):  
Cliff Searfass ◽  
Jeffrey P. Milligan ◽  
Michael S. Lashley
Keyword(s):  
Numerical Modeling ◽  
Fusion Zone ◽  
High Density Polyethylene ◽  
Phased Array ◽  
High Density ◽  
Scanning Method ◽  
Empirical Results ◽  
Ultrasonic Evaluation ◽  
Ultrasonic Phased Array ◽  
Effects Of Temperature

This paper presents a method for investigating the integrity of high density polyethylene (HDPE) butt fusion joints and mitered joints. The scanning technique utilizes an ultrasonic phased array pitch-catch scanning method that provides full volumetric coverage of the fusion zone for the detection of inclusions and surface-breaking defects. Empirical results supported by numerical modeling are presented. Additionally, the effects of temperature on focalization and the proper countermeasures are discussed.

Determination of Creep Properties of PE 4710 Cell Classification 445574C High Density Polyethylene

2014 ◽  
Author(s):  
Timothy M. Adams ◽  
Shawn Nickholds ◽  
Douglas Munson ◽  
Jeffery Andrasik
Keyword(s):  
Carbon Steel ◽  
Pressure Vessel ◽  
High Density Polyethylene ◽  
Nuclear Power ◽  
Power Plants ◽  
High Density ◽  
Labor Costs ◽  
Cell Classification ◽  
Service Water ◽  
Hdpe Pipe

For corroded piping in low temperature systems, such as service water systems in nuclear power plants, replacement of carbon steel piping with high density polyethylene (HDPE) is a cost-effective solution. Polyethylene pipe can be installed at much lower labor costs than carbon steel pipe and HDPE pipe has a much greater resistance to corrosion. The ASME Boiler and Pressure Vessel Code, Section III, Division 1 currently permits the use of non-metallic piping in buried safety Class 3 piping systems. Additionally, HDPE pipe has been successfully used in non-safety-related systems in nuclear power facilities and is commonly used in other industries such as water mains and natural gas pipelines. This paper presents the results of creep testing of PE 4710 cell classification 445574C pipe compliant with ASME Boiler and Pressure Vessel Code material requirements. This information was developed to support and provide a strong technical basis for material properties of HDPE pipe for use in ASME Boiler and Pressure Vessel Code, Section III New Construction and Section XI repair or replacement activities. The data may also be useful for applications of HDPE pipe in commercial electric power generation facilities and chemical, process and waste water plants via its possible use in the B31 series piping codes. The report provides long term creep and modulus data, as well as an analysis of the stress dependency of both.

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