In-Line Inspection in Lieu of Hydrostatic Testing for Low Frequency Electric Resistance Welded Pipe

Author(s):  
Matt Krieg ◽  
J. Bruce Nestleroth ◽  
Thomas Hennig ◽  
Harvey Haines

Hydrostatic testing is a costly, operationally-impactful method of verifying seam integrity in low frequency electric resistance welded (LF-ERW) line pipe. Pipeline operators seek an alternative seam assessment method that provides a sufficiently conservative integrity assessment without the potentially negative impacts of hydrostatic testing. As in-line inspection (ILI) and field nondestructive evaluation (NDE) improve, pipelines that have been historically hydrostatic tested can now use ILI to ensure operational integrity. The improved ILI technology assessed in this work is an enhanced ultrasonic crack ILI tool with higher circumferential resolution and finer axial sample intervals. Magnetic ILI data from previous assessments is used to assist in anomaly identification. In addition to utilizing NDE technologies such as phased array, the emerging full matrix capture (FMC) imaging method that quantifies the size, position, and orientation of seam weld anomalies was examined. This paper discusses the work performed to ensure the efficacy of the improved ILI and NDE methods to accurately detect and quantify all anomalies that could possibly fail a hydrostatic test. An early step in the process was removing three sections of pipe from service for technology calibration and assessment. Each spool was examined with ILI technology in a pump-through facility, inspected using many NDE methods and then destructively tested. These results were communicated to ILI analysts and used to calibrate and improve the interpretation of the inspection results. Then the pipeline was inspected as part of the scheduled integrity assessment. Using field evaluation of anomalies detected by ILI, pipes were selected for removal from service to examine destructively. This paper presents the inspection and destructive testing results in addition to prognosis for the use of the ILI in lieu of hydrostatic testing for LF-ERW pipe.

Author(s):  
John F. Kiefner

The new regulations, Part 195 Section 195.452, require that special integrity assessments be made to address potential seam-defect problems in low-frequency-welded ERW (electric-resistance-welded) pipe materials where a failure of such materials could have an impact on a high-consequence area (HCA). The spirit of this requirement appears to require action if, and only if, significant seam-related deficiencies are in evidence or if they can be reasonably anticipated. This leaves open the option of categorizing these types of pipelines by performance such that potentially problematic pipeline segments can be subjected to special (i.e., seam-quality) inspections while those that show little or no propensity for such problems can be subjected to metal loss and deformation inspections only. This document is intended to establish a systematic procedure to permit an operator to characterize the relevant ERW pipe segments as to the likelihood of significant seam-related deficiencies. The author is particularly grateful to Rich Turley of Marathon Ashland Pipe Line LLC for helping to formulate the essential steps in deciding when an integrity assessment is needed. Rich made significant inputs to Figure 1 of this document.


Author(s):  
Luis Torres ◽  
Matthew Fowler ◽  
Jason Bergman

In the pipeline industry, a widely accepted methodology for integrity crack management involves running ultrasonic In-Line Inspection (ILI) technologies. After an ILI tool run is completed, the performance of the tool is typically validated by excavating the pipeline and conducting in-the-ditch investigations. Ultrasonic Non-Destructive Evaluation (NDE) techniques are used in the field to characterize and measure crack-like features. These in-the-ditch measurements are compared back to ILI results in order to validate tool performance and drive continuous technology improvements. Since validation of the ILI tool relies on NDE measurements, acquiring accurate and representative data in the field is a critical step in this integrity crack management approach. Achieving an accurate field inspection comes with its challenges, some of which relate to complex long seam weld conditions present in older vintage pipelines including: weld misalignment, weld trim issues, and dense populations of manufacturing anomalies. In order to better understand the challenges associated with complex long seam weld conditions, an evaluation and comparison of the performance of NDE technologies currently available was conducted. In this study, a portion of a Canadian pipeline with complex long seam weld conditions was cut-out and removed from service. Multiple NDE crack inspection technologies and methods from three different vendors were used to assess the condition of the long seam weld. Conventional Ultrasonic Testing (UT), Phased Array Ultrasonic Testing (PAUT), Time of Flight Diffraction (TOFD), and variations of Full Matrix Capture Ultrasonic Testing (FMCUT) were used to assess the long seam weld and their results were compared. The performance of all NDE technologies is baselined by comparing them with destructive examination of sections of the long seam weld. The newer NDE assessment methodologies were shown to be consistently more accurate in characterizing long seam features.


Author(s):  
Jai Prakash Sah ◽  
Mohammad Tanweer Akhter

Managing the integrity of pipeline system is the primary goal of every pipeline operator. To ensure the integrity of pipeline system, its health assessment is very important and critical for ensuring safety of environment, human resources and its assets. In long term, managing pipeline integrity is an investment to asset protection which ultimately results in cost saving. Typically, the health assessment to managing the integrity of pipeline system is a function of operational experience and corporate philosophy. There is no single approach that can provide the best solution for all pipeline system. Only a comprehensive, systematic and integrated integrity management program provides the means to improve the safety of pipeline systems. Such programme provides the information for an operator to effectively allocate resources for appropriate prevention, detection and mitigation activities that will result in improved safety and a reduction in the number of incidents. Presently GAIL (INDIA) LTD. is operating & maintaining approximately 10,000Kms of natural gas/RLNG/LPG pipeline and HVJ Pipeline is the largest pipeline network of India which transports more than 50% of total gas being consumed in this country. HVJ pipeline system consists of more than 4500 Kms of pipeline having diameter range from 04” to 48”, which consist of piggable as well as non-piggable pipeline. Though, lengthwise non-piggable pipeline is very less but their importance cannot be ignored in to the totality because of their critical nature. Typically, pipeline with small length & connected to dispatch terminal are non-piggable and these pipelines are used to feed the gas to the consumer. Today pipeline industries are having three different types of inspection techniques available for inspection of the pipeline. 1. Inline inspection 2. Hydrostatic pressure testing 3. Direct assessment (DA) Inline inspection is possible only for piggable pipeline i.e. pipeline with facilities of pig launching & receiving and hydrostatic pressure testing is not possible for the pipeline under continuous operation. Thus we are left with direct assessment method to assess health of the non-piggable pipelines. Basically, direct assessment is a structured multi-step evaluation method to examine and identify the potential problem areas relating to internal corrosion, external corrosion, and stress corrosion cracking using ICDA (Internal Corrosion Direct Assessment), ECDA (External Corrosion Direct Assessment) and SCCDA (Stress Corrosion Direct Assessment). All the above DA is four steps iterative method & consist of following steps; a. Pre assessment b. Indirect assessment c. Direct assessment d. Post assessment Considering the importance of non-piggable pipeline, integrity assessment of following non piggable pipeline has done through direct assessment method. 1. 30 inch dia pipeline of length 0.6 km and handling 18.4 MMSCMD of natural gas 2. 18 inch dia pipeline of length 3.65 km and handling 4.0 MMSCMD of natural gas 3. 12 inch dia pipeline of length 2.08 km and handling 3.4 MMSCMD of natural gas In addition to ICDA, ECDA & SCCDA, Long Range Ultrasonic Thickness (LRUT-a guided wave technology) has also been carried out to detect the metal loss at excavated locations observed by ICDA & ECDA. Direct assessment survey for above pipelines has been conducted and based on the survey; high consequence areas have been identified. All the high consequence area has been excavated and inspected. No appreciable corrosion and thickness loss have observed at any area. However, pipeline segments have been identified which are most vulnerable and may have corrosion in future.


2013 ◽  
Vol 778 ◽  
pp. 321-327 ◽  
Author(s):  
Steffen Franke ◽  
Bettina Franke ◽  
Florian Scharmacher

The assessment of timber structures is a permanent task to check the normal function of individual structural timber elements. Non-destructive testing methods are preferred but the value of the information is limited due to the performance of the applied assessment method. However, X-ray is a technology which allows a view into the structural member or the connections. The mobile X-ray technology has been used in laboratory tests and practical situations at existing structures and led to excellent results which allowed detailed analyses. The method and its possibilities for non-destructive testing of timber structures will be presented. The results reached show a high potential for an effective assessment of existing structures including connections and structural timber members.


Author(s):  
Nuria Sanchez ◽  
Özlem E. Güngör ◽  
Martin Liebeherr ◽  
Nenad Ilić

The unique combination of high strength and low temperature toughness on heavy wall thickness coils allows higher operating pressures in large diameter spiral welded pipes and could represent a 10% reduction in life cycle cost on long distance gas pipe lines. One of the current processing routes for these high thickness grades is the thermo-mechanical controlled processing (TMCP) route, which critically depends on the austenite conditioning during hot forming at specific temperature in relation to the aimed metallurgical mechanisms (recrystallization, strain accumulation, phase transformation). Detailed mechanical and microstructural characterization on selected coils and pipes corresponding to the X80M grade in 24 mm thickness reveals that effective grain size and distribution together with the through thickness gradient are key parameters to control in order to ensure the adequate toughness of the material. Studies on the softening behavior revealed that the grain coarsening in the mid-thickness is related to a decrease of strain accumulation during hot rolling. It was also observed a toughness detrimental effect with the increment of the volume fraction of M/A (martensite/retained austenite) in the middle thickness of the coils, related to the cooling practice. Finally, submerged arc weldability for spiral welded pipe manufacturing was evaluated on coil skelp in 24 mm thickness. The investigations revealed the suitability of the material for spiral welded pipe production, preserving the tensile properties and maintaining acceptable toughness values in the heat-affected zone. The present study revealed that the adequate chemical alloying selection and processing control provide enhanced low temperature toughness on pipes with excellent weldability formed from hot rolled coils X80 grade in 24 mm thickness produced at ArcelorMittal Bremen.


2021 ◽  
pp. 136943322110384
Author(s):  
Xingyu Fan ◽  
Jun Li ◽  
Hong Hao

Vibration based structural health monitoring methods are usually dependent on the first several orders of modal information, such as natural frequencies, mode shapes and the related derived features. These information are usually in a low frequency range. These global vibration characteristics may not be sufficiently sensitive to minor structural damage. The alternative non-destructive testing method using piezoelectric transducers, called as electromechanical impedance (EMI) technique, has been developed for more than two decades. Numerous studies on the EMI based structural health monitoring have been carried out based on representing impedance signatures in frequency domain by statistical indicators, which can be used for damage detection. On the other hand, damage quantification and localization remain a great challenge for EMI based methods. Physics-based EMI methods have been developed for quantifying the structural damage, by using the impedance responses and an accurate numerical model. This article provides a comprehensive review of the exciting researches and sorts out these approaches into two categories: data-driven based and physics-based EMI techniques. The merits and limitations of these methods are discussed. In addition, practical issues and research gaps for EMI based structural health monitoring methods are summarized.


Author(s):  
Mahesh Dissanayake ◽  
Tariq Pervez Sattar ◽  
Shehan Lowe ◽  
Ivan Pinson ◽  
Tat-hean Gan

Purpose Mooring chains used to stabilise offshore floating platforms are often subjected to harsh environmental conditions on a daily basis, i.e. high tidal waves, storms, etc. Therefore, the integrity assessment of chain links is vital, and regular inspection is mandatory for offshore structures. The development of chain climbing robots is still in its infancy due to the complicated climbing structure presented by mooring chains. The purpose of this paper is to establish an automated climbing technique for mooring chain inspection. Design/methodology/approach This paper presents a Cartesian legged tracked-wheel crawler robot developed for mooring chain inspection. The proposed robot addresses the misalignment condition of the mooring chains which is commonly evident in in situ conditions. Findings The mooring chain link misalignment is investigated mathematically and used as a design parameter for the proposed robot. The robot is validated with laboratory-based climbing experiments. Practical implications Chain breaking can lead to vessel drift and serious damage such as riser rupture, production shutdown and hydrocarbon release. Currently, structural health monitoring of chain links is conducted using either remotely operated vehicles which come at a high cost or by manual means which increase the danger to human operators. The robot can be used as a platform to convey equipment, i.e. tools for non-destructive testing/evaluation applications. Originality/value This study has upgraded a previously designed magnetic adhesion tracked-wheel mooring chain climbing robot to address the misalignment issues of operational mooring chains. As a result of this study, the idea of an orthogonally placed Cartesian legged-magnetic adhesion tracked wheel robotic platform which can eliminate concerns related to the misaligned mooring chain climbing has been established.


2016 ◽  
Vol 712 ◽  
pp. 303-307 ◽  
Author(s):  
Maxim V. Trigub ◽  
Stanislav N. Torgaev ◽  
Gennadiy S. Evtushenko ◽  
Vitaliy V. Drobchik

The imaging results of different processes blocked from the observation by the intense background light are presented in this paper. Active optical systems based on high-frequency brightness amplifier are used to decrease the negative factor of the glare. The experimental and modeling results on obtaining high pulse repetition frequencies (PRF) (more than 100 kHz) of copper bromide vapor brightness amplifiers operating in a low input energy mode are shown. The use of metal vapor brightness amplifiers for visual non-destructive testing of fast processes obscured by the glare is also discussed. It has been shown that the imaging method proposed in this paper proves to be the most reliable to obtain the information about objects or processes in a real time mode using high PRF CuBr active media.


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