IMPORTANCE OF QUALITY VALIDATION TO COMPETITIVE STRATEGIES OF PIPE MANUFACTURERS BY JEFFREY T STETSON*

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1 IMPORTANCE OF QUALITY VALIDATION TO COMPETITIVE STRATEGIES OF PIPE MANUFACTURERS BY JEFFREY T STETSON* SYNOPSIS: Pipes and tubes are critical mechanical structures used in all aspects of the Oil and Gas industry. Whether it be drill strings, well casings and gathering lines in the upstream world to on and off shore midstream transmission pipelines to distribution lines, the integrity of an individual pipe is paramount to safety and profitability of major Oil and Gas companies. This paper outlines inspection standards required for various tubular product types used in the Oil and Gas industry and describes current and forward looking ultrasonic inspection methods that can be implemented now to meet and exceed these requirements. Understanding the impact of inspection capability on the manufactured value of tubes and pipes will allow Manufacturers to choose a strategy to improve their overall competitiveness on a global basis. Keywords: Ultrasonic Inspection, Phased Array, Matrix Array, Value, Midstream, Upstream, LSAW, Seamless Pipe, Drill String, Casing, ShapeUT * Senior Product Manager, Automated Ultrasonic Inspection Systems, BS Mechanical Engineering, BS Physics GE Oil & Gas, Lewistown, PA, USA 1

2 Cost of Failure The importance of the integrity of pipes used throughout the Oil and Gas value chain should not be underestimated. Pipe failures have caused the industry billions not only in replacing failed assets but in lost productivity and environmental remediation. PHMSA Pipeline Incidents: ( ) Incident Type: Significant System Type: ALL State: ALL Calendar Year Number Fatalities Injuries Total Cost Current Year Dollars $110,377, $174,516, $178,313, $257,659, $79,086, $124,067, $163,459, $314,362, $1,476,994, $157,117, $147,800, $592,290, $180,360, $1,854,123, $447,407, $233,813, $355,213, $305,253, $338,201, $298,245,979 Grand Total 5, ,299 $7,788,665,524 PHMSA Pipeline Incidents: Multi-Year Averages ( ) Table 1, USA Significant Pipeline Failure Incidents [1] In the United States, regulators track all midstream pipeline failure. The chart in Table 1 details the cost of pipeline failures by year in the USA classified as significant, those failures with costs over $50,000. While data on actual failure mode is often difficult to determine, it is estimated that the largest single contributor to these pipeline failures, in excess of 20%, is due to corrosion related factors but a significant portion, 7%, is related to base metal and weld failures, failures due to embedded flaws or weld quality issues that could have been caught during the manufacturing process by employing the right inspection methods. 2

3 In the upstream Oil and Gas segment, the trend towards deeper wells, horizontal drilling technologies and the fracking process pose additional challenges to pipe integrity. Increasing torsional loads and shear stresses on drill strings, higher pressure, deeper and longer pipe runs increasing the load on well casings all contribute to primary failure mechanisms of these assets. Recovering from a failed drill string can be as simple as grabbing the failed end and winching the string out of the hole to as costly as abandoning the well site and redrilling when the string is not able to be retrieved. Depending on the circumstances, costs of recovering from a drill failure can easily reach seven figures. The same is true of failed well casings where remediation can range from recasing to complete well abandonment. The mechanism and cause of a given pipe failure is not always evident and the asset owner often absorbs the cost of failure. In cases where failure mechanisms can be identified, an increasing trend is to pass down a portion or all of these costs to the manufacture of the pipe. How do pipe manufacturers protect themselves against this type of activity? First by ensuring that contracts are specific on the detailed types, locations, and sizes of the flaws that you are signing up to inspect pipe to and secondly ensuring that your inspection methods are up to the task. Variations in Inspection Standards Inspection requirements for pipe fabrication are detailed in a number of industry specifications from the American Petroleum Institute (API), DNV, ASTM, and other industry wide accepted standards. In addition, leading petroleum companies such as Shell, Exxon Mobil, Chevron, Aramco and others have developed their own, even tighter standards to help drive improved integrity of piping assets. Some pipeline project also have their own special standards. API standards are admittedly the base general standards that a majority of the pipe used throughout the oil and gas sector are inspected to both seamless and Figure 1, LSAW Probe Layout 3

4 welded. API 5L is often referenced as the standard for line pipe. Figure 1 compares an ultrasonic probe layout to meet the API 5L requirement to inspect the weld seam on 25mm wall LSAW pipe with the Shell DEP specification for the same pipe construction. Seamless pipe constructions prevail in well casings, off shore risers, and in drill strings. The elimination of a linear weld seam in these constructions certainly provides an inherent integrity benefit, but the fabrication process for a seamless pipe yields another type of potential anomaly off axis oblique defects. This type of defect is directly attributed to the processes used to manufacture seamless pipes. API 5CT is the general standard for pipe used in casings and tubes. Like the previous example there is significant variation in the inspection requirements of the base API standards as compared to specific oil company standards. To illustrate this the following graphic demonstrates the reference standard indications required to baseline ultrasonic inspection sensitivity for a full body seamless pipe inspection comparing the API 5CT requirement carbons steel pipe with the Exxon Mobil EMQSP 6.9 requirement for CRA pipe. Figure 2, Seamless Pipe Reference Standards What Drives Value The previous examples exemplify the sensitivity of asset owners with the integrity of their piping assets. In all cases, large oil companies and other asset owners are more stringent in their demands on quality then the general buying population. It s a matter of dollars and sense common sense. The costs of failure are just too high and drives value in providing pipe built and tested to a higher quality standard. Every successful public company manages cost and strives for quality in its products and services 4

5 focusing on one of the following pillars low cost provider, product excellence, and service excellence. With respect to the oil and gas sector, high quality pipe inspected to the highest standard holds the highest value - period. Future View Ultrasonic inspection technologies available to pipe manufacturers today often outpace even the most discerning current industry standards. The ability to control the sound beam profile of an ultrasonic inspection and gather large amounts of data to analyze an inspection in real time are two important factors in the speed of ultrasonic inspection evolution both enabled with the dramatic increase in computing power and data bandwidth of current digital electronics. Ultrasonic transducer arrays have now matured and taken the place of conventional ultrasound where, in the past, one transducer was designed for a specific performance capability and that capability only. The true benefit of arrays is that their ultrasonic sound beams can be electronically tailored to fill a variety of different inspection needs with a single transducer. We can now dynamically adjust focal lengths and steer ultrasonic sound beams in real time with one transducer. So what does all of this mean with respect to getting the most value out of an inspection process? It all comes down to better defect detection capability reducing integrity risks for the end user and improving overall shop floor efficiency through the use of inspection tools that can be easily tailored for different inspection needs. Opportunities in Midstream LSAW Transmission Pipe High Sulphurr bearing crude oils are very corrosive to conventional carbon steel transmission pipelines. As a result, the industry has moved to Corrosion Resistant Alloy (CRA) Cladded base material to transport these products. The Kashagan oil field rebuild is a recent dramatic example where two 95km carbon steel transmission pipelines were replaced by Clad pipe at a rumored cost of $3.6B. Mills supplying the bulk of Clad transmission pipe were originally designed to build conventional carbon steel LSAW pipe. In most cases with minor modifications to a manufacturing process and employing the appropriate ultrasonic testing system, a mill can be converted quickly to supplying high quality Clad pipe at a significant increase in tonnage price for the end product. The ability to quickly adapt an ultasonic inspection process to a new pipe construction without additional capital outlay is only made possible if a supplier has the foresight to purchase a phased array based ultrasonic test system to future proof his inspection facility [2]. Opportunities in Seamless Pipe As stated earlier, the increasing loads and associated stresses applied to piping structures in upstream oil and gas are driving asset owners to relook at pipe mill inspection standards to ensure overall integrity of the delivered pipe. No place is this more evident than the increased focus on oblique defects in seamless pipe those embedded defects located at various angles to the axis of the pipe. What makes these defects so troubling is that they are easily missed in an inspection unless an ultrasonic beam is focused perpendicular to their orientation. The traditional conventional ultrasonic approach would be to build a system with ultrasonic probes mechanically 5

6 aligned to expected oblique angles of a potential flaw. Using this technique to ensure obliques are not missed would require a very complex and expensive inspection process. The solution to this problem is enabled by using two dimensional ultrasonic arrays coupled with smart algorithms and high speed signal processing to detect oblique flaws in essentially any orientation with respect to the pipe axis. The ultrasonic output of such a technique is shown in Figure 3 where GE s ShapeUT function takes a target sound field shape and applies a tailored transfer function based on the desired outcome to generate a three dimensional acoustic hologram in a single firing of the ultrasonic transducer [3]. Figure 3, ShapeUT Ultrasonic Sound Field The data received is then processed and provides the operator with a 360 degree analysis of oblique flaws. While no inspection standard currently exists that specifies 360 degree oblique flaw detection, it is highly probable that such standards will exist in the near future. Summary The cost of remediation, lost economic opportunity, environmental impact, and loss of human life of a failed Oil and Gas piping system is very high. Asset owners are driving increased scrutiny on the quality of fabricated pipes to help minimize these costs. New ultrasonic inspection technologies exist with capabilities that far exceed current published standards. Those pipe mills that strive to be best in class and appropriately invest in these new inspection techologies are not only well positioned to meet current industry demands, they are also positioned to gain share by providing products that meet or exceed the ever tightening inspection requirements of their customers. 6

7 References [1] Pipeline and Hazardous Materials Safety Administration(PHMSA), Pipeline Incident 20 Year Trends, (2017) [2] J. Beissel, et al., Advanced Manufacturing, Testing Methods for CLAD Pipes, Pipeline and Gas Journal (2016) [3] S. Falter, et al., Tailored Ultrasound Fields for Application in Ultrasonic Testing, 19th World Conference on Non-Destructive Testing (2016) 7