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*Published in World Pipelines Magazine

The oil and gas pipeline industry has been under close scrutiny for a long time. It leads the way as one of the most regulated industries in the world, and for good reason.  With so many safety-related, social and environmental factors at stake, comprehensive regulation ensures rigorous standards for the design, construction, operation and maintenance of O&G pipeline systems.

Global economics and political activism also play a role in shaping today’s conversation about pipelines. In North America, public debates about the Keystone XL Pipeline have dominated much of the recent news, compelling operators to vigorously participate in the discussion and advocate their integrity management programs. Although Keystone has been put on hold, social capital can assist in getting projects of this magnitude on the radar again.

Through it all, much of the dialogue has focused on the industry’s commitment to protecting communities and the environment from risk by means of rigorous pipeline integrity management programs. As a result, the requirement for increased pipeline safety drives innovative research into improving the sensitivity and reliability of inline inspection (ILI) tools.

Most operators already deploy trusted inline technologies that detect structural deterioration and help maintain pipeline integrity. However, with pressure mounting from stricter regulation, increased operational costs, commodity price-driven budgetary pressure, and often limited available resources, operators face an increasing number of challenges, including vigilance from highly engaged consumer groups.

Although the pressure to perform is greater than ever, operators are responding appropriately with greater confidence in modern technologies to assist in the operation and monitoring of their pipeline systems.

Better ILI tools instill better confidence in containment

To have confidence in the pipeline, operators must have confidence in the capabilities of ILI tools to detect small anomalies that could lead to potential failures.  They must also trust the reliability and interpretation of the data, knowing with as much certainly as possible that the depth, size and location of the pipe wall anomaly is correct.

Overall the news is good. Between 2002 and 2013, Canadian Energy Pipeline Association (CEPA) member companies were able to transport oil and natural gas with a 99.999 percent safety record. While that statistic sounds impressive, headline-grabbing pipeline incidents do occur, (in 2014 there were 122 natural gas and liquid releases) and when that happens, the repercussions can undo years of containment management trust and goodwill.

While the oil and gas industry boasts a remarkable safety record, a reliance on conventional tools limit the near perfect record.  As much as the technologies have been refined, regulators have noted that inline inspections don’t pick up all defects, and expedient follow-through often depends on the people analyzing the data and planning repairs, a process that can take months.

“Despite their sophistication, the detection capabilities of inline inspection tools have limitations,” the US National Transportation Safety Board noted in its report on the 3.3-million-liter 2010 spill in Michigan.

Limitations of conventional ILI inline inspection technologies

The oil and gas pipeline industry has access to an extensive toolbox of technologies for robust integrity programs. Some tools address cracks or corrosion issues, while other tools focus on stress, pressure and product containment. Cost, resolution, reliability, data analysis speed – each technology has its own strengths and limitations, with no silver bullet as the single solution for collecting pipeline condition information.

For example, there is a strongly-held belief in hydrostatic testing as a reliable method to test a pipeline’s integrity. One of the earliest inspection techniques, hydrostatic testing determines if a pipeline can hold its operating pressure. A form of destructive testing, hydrostatic inspection involves purging the product, flooding the line with water, pressurizing it to a predetermined level and maintaining the pressure for a period. Based on the results, detected anomalies in pressure, volume and density can be a precursor to leaks.

Critics however, argue and have quite effectively demonstrated that the hydrostatic tests lack the ability to monitor ongoing corrosion or cracking and that the high pressure environment can exacerbate previously small defects, increasing risk of future rupture.

Smart pigs for detecting large cracks and corrosion

Unlike hydrostatic testing, which is often conducted on pipelines for acceptance testing or for pipelines recently rehabilitated, pigging is the more commonly accepted method of testing pipeline integrity.

While newer “smart” pigs have an excellent reputation for accuracy, their efficacy is often limited to detecting corrosion and cracking that exceeds the threshold for detection of the technology.  Small corrosion pits and cracks, especially cracks grouped in a colony, can pose a challenge to most conventional ILI pigging devices.

The various ILI technologies are sensitive to axial or circumferential defects, and each has limitation for minimum aspect ratios or cross sectional wall loss area before the ILI tool can report the anomaly.  It is also possible to have cracks and wall loss pits that are in close proximity to girth welds, long seams, and other features in the pipe, which can mask the defect, preventing the ILI tool from properly identifying and sizing.  As a result, it is possible to have leaking cracks and corrosion pits that are too small to be sized and reported from conventional ILI.

Not all lines are piggable

Some pipes are more suitable for pigging than others. While most oil and gas transmission lines were built in long straight sections suitable for pig runs, sections with small diameter pipe and small bend radius pipe configurations can limit many ILI tools.  Lines with expansion loops and miter bends, and in the case of natural gas lines, those with reduced port valves, are factors that can prohibit or restrict the traversing of online tools.

Mass balance measurement and other leak detection tools

To make up for the limitations of conventional ILI technologies, operators often deploy measurement methods and leak detection technologies to complement their integrity programs.

Mass balance is a means of detecting leaks by measuring the mass of product entering the pipeline compared to the mass exiting the pipeline. The limitation for detecting small leaks is the sensitivity of the mass meters being used (2-4% accuracy for conventional orifice meters and 0.25% for turbine meters), and the fact that the product temperature and pressure changes as it moves through the pipeline.

While mass balance is a means to determine leaks, it is also recognized that making actual measurement of mass from volume (through a meter) at different temperature and pressure going in versus coming out of the pipeline, in real time, is difficult, and not very precise or sensitive to small leaks.

As a result, a leak has to release more product than the total tolerance of the mass balance system before a positive leak/release event is alarmed.

Acoustic leak detection

Minute cracks are often preliminary indicators of potential small leaks that produce acoustic emissions at levels often unrecognizable over background noise.

Acoustic leak detection can be conducted with geophones/hydrophones, comparators and acoustic fiber optic techniques, and each of these acoustic tools is subject to different background noise limitations to determine leak detection thresholds.  Not only can these tools have limitations to prevent small leak detection, the expense from installing permanent acoustic systems may reduce the practicality of these technologies.

Emerging technologies on the horizon

To complement hydrostatic testing, conventional pigging tools, and leak detection technologies, the oil and gas industry is evaluating a growing number of emerging external confirmation of containment technologies. These include vapour-sensor systems, hydrocarbon-sensing cables that change in the presence of hydrocarbons, internal pressure wave based tools and fibre-optic based systems that detect temperature changes and acoustic signals associated with leaks.

While these technologies offer hope for more precise surveys, they have yet to be universally accepted or proven. Many are still under development and often require economically impractical installation requirements.

However, there is an innovative, multi-sensor ILI platform that has been used in integrity management programs since 2006, gaining the attention of major pipeline players who have tested the platform, which has now been used on over 25,000 kilometers of pipeline in total.

Introducing SmartBall® technology for Oil & Gas pipelines

To provide a realistic snapshot of a pipe’s condition, many proactive operators are deploying SmartBall technology,  a free-swimming multi-sensor tool for long inspections of piggable and difficult to pig liquid and gas pipelines 4 inches and larger. This advantage makes the ball-shaped tool an excellent choice for traversing not just standard diameter pipes, but for smaller diameter liquid lines and for gas pipelines with loops and frequent sharp bends and heavy wall fittings.

During an inspection, the SmartBall sensors collect acoustic, pressure, temperature, magnetic and inertial data from inside the pipeline.

Primary applications for the SmartBall tool

SmartBall surveys can be conducted independently, at regular intervals, as part of a routine pipeline integrity management program, or as a value-add to inspection programs along with hydro-testing, ILI, or direct assessment.

The tool is launched and retrieved at existing pig traps and is tracked using proprietary acoustic receivers and/or Armadillo pig tracking boxes (AGMs). The location data from acoustic receivers and tracking boxes is used during data analysis to locate any anomalies.

SmartBall technology has three primary applications, and the multi-sensor tool can provide a variety of pipeline data.

1. Confirmation of Containment

Regular confirmation of containment surveys are an important part of integrity management as leaks are often a preliminary indicator of pipe failure.

Unlike conventional leak detection systems, confirmation of containment with SmartBall supplements these systems. The SmartBall tool directly passes leaks, and is therefore capable of detecting losses as small as 150 mL/min, which can be several orders of magnitude more sensitive than conventional methods.

SmartBall surveys can also complement regular ILI surveys by addressing potential pinhole anomalies that have aspect ratios below the reporting threshold of ILI systems.

2. Pressure and Temperature profiles

As the SmartBall is rolling and not sealing against the pipe ID, as conventional pigs do, the tool can also record precise pressure and temperature profiles. The SmartBall platform can be deployed in gas pipelines, where pressure and temperature profiles can be integrated into flow models to assess the points where water vapor may condense out of the gas.

The tool can also be used to assess the point where high temperatures from pump or compressor output may have affected the pipe coating, as well as in settings to validate and improve SCADA and mass balance systems.

3. Pipe Wall Assessment and Inertial Mapping

During inspection, the SmartBall Pipe Wall Assessment (PWA) tool collects magnetic data that can provide a screening of the pipe wall for stress resulting from features like large cracks, large wall loss, dents and points of excessive loading.  The test can also complement hydrostatic testing, as it can survey the pipeline before and after hydro-tests to identify stress that is indicative of pressure reversals.

In addition, the SmartBall PWA tool can produce a girth weld and joint tally for the pipeline, as well as can confirm locations of bends and general geometry of the pipeline.

Helping operators make better decisions

Admittedly, SmartBall is not designed to compete with high resolution technologies like Magnetic Flux Leakage (MFL), which can provide detailed wall loss data.

What SmartBall can do is complement other integrity tools by providing additional data sets to ensure pipeline integrity. In a single deployment, it can detect anomalies associated with pinhole leaks and stress that doesn’t necessarily involve wall loss; e.g. geotechnical strains.  It can also detect change in pressure and temperatures.

Ultimately, the SmartBall tool can help capture enough data to confirm the integrity of the pipe and give operators enough microscopic knowledge to make better, informed, risk-based decisions on the health of their pipelines.

Utilities have limited asset management funding at their disposal and yet waiting for failures to happen before repairing or replacing critical water mains is simply not a cost-effective option.

Cities need a working water infrastructure. It’s that simple. The solution, though, has tended to be a lot more complicated. The majority of urban water infrastructures are old and reaching the end of their usage expectancy. In addition, most are buried deep beneath the very cities they service and system-wide pipeline replacement is far too costly. Yet, if those large-diameter pressurized pipelines unexpectedly fail, the consequences can be catastrophic, to the city and the people living there. It can also shake the public’s confidence in the utility, harming its reputation in the process.

The fact is, not all old pipe is bad pipe. The Water Research Foundation Report found that age is not a primary factor for pipe failure. Many buried pipes, well over 100 years old, can still be considered in “like new” condition. Through extensive research and data from more than 14,000 milesof pressure pipeline inspection, we have found that less than 1% of pipes are damaged enough to need immediate repair. And that’s good news for cash-strapped, resource-short pipeline operators.

Unfortunately, there is no “one technology fits all” solution to this problem, which is why the choice of assessment tools is critical. The smartest choice is to deploy different but complimentary technologies that can collect the robust condition data required to evaluate which pipes need repair or replacement and which should be left alone. This pipe-by-pipe approach helps utilities make informed decisions based on assessment results, which in turn can reduce capital costs by as much as 90 percent.

Pure Technologies’ Assess and Address® approach is not only logical, scalable and cost effective, it also provides the highest return on investment.

Beginning with Pure’s risk-based assessment method followed by the deployment of complimentary technologies – like SoundPrint® – we work together with utilities to help facilitate pro-active, cost effective renewal and enduring pipeline management strategies that help keep our cities up and running for years to come.

Hanging rock with a sheep above

Don’t Get Stuck Between a Rock and a Hard Place

*Published in World Pipelines Magazine

The oil and gas pipeline industry has been under close scrutiny for a long time. It leads the way as one of the most regulated industries in the world, and for good reason.  With so many safety-related, social and environmental factors at stake, comprehensive regulation ensures rigorous standards for the design, construction, operation and maintenance of O&G pipeline systems.

Global economics and political activism also play a role in shaping today’s conversation about pipelines. In North America, public debates about the Keystone XL Pipeline have dominated much of the recent news, compelling operators to vigorously participate in the discussion and advocate their integrity management programs. Although Keystone has been put on hold, social capital can assist in getting projects of this magnitude on the radar again.

Through it all, much of the dialogue has focused on the industry’s commitment to protecting communities and the environment from risk by means of rigorous pipeline integrity management programs. As a result, the requirement for increased pipeline safety drives innovative research into improving the sensitivity and reliability of inline inspection (ILI) tools.

Most operators already deploy trusted inline technologies that detect structural deterioration and help maintain pipeline integrity. However, with pressure mounting from stricter regulation, increased operational costs, commodity price-driven budgetary pressure, and often limited available resources, operators face an increasing number of challenges, including vigilance from highly engaged consumer groups.

Although the pressure to perform is greater than ever, operators are responding appropriately with greater confidence in modern technologies to assist in the operation and monitoring of their pipeline systems.

Better ILI tools instill better confidence in containment

To have confidence in the pipeline, operators must have confidence in the capabilities of ILI tools to detect small anomalies that could lead to potential failures.  They must also trust the reliability and interpretation of the data, knowing with as much certainly as possible that the depth, size and location of the pipe wall anomaly is correct.

Overall the news is good. Between 2002 and 2013, Canadian Energy Pipeline Association (CEPA) member companies were able to transport oil and natural gas with a 99.999 percent safety record. While that statistic sounds impressive, headline-grabbing pipeline incidents do occur, (in 2014 there were 122 natural gas and liquid releases) and when that happens, the repercussions can undo years of containment management trust and goodwill.

While the oil and gas industry boasts a remarkable safety record, a reliance on conventional tools limit the near perfect record.  As much as the technologies have been refined, regulators have noted that inline inspections don’t pick up all defects, and expedient follow-through often depends on the people analyzing the data and planning repairs, a process that can take months.

“Despite their sophistication, the detection capabilities of inline inspection tools have limitations,” the US National Transportation Safety Board noted in its report on the 3.3-million-liter 2010 spill in Michigan.

Limitations of conventional ILI inline inspection technologies

The oil and gas pipeline industry has access to an extensive toolbox of technologies for robust integrity programs. Some tools address cracks or corrosion issues, while other tools focus on stress, pressure and product containment. Cost, resolution, reliability, data analysis speed – each technology has its own strengths and limitations, with no silver bullet as the single solution for collecting pipeline condition information.

For example, there is a strongly-held belief in hydrostatic testing as a reliable method to test a pipeline’s integrity. One of the earliest inspection techniques, hydrostatic testing determines if a pipeline can hold its operating pressure. A form of destructive testing, hydrostatic inspection involves purging the product, flooding the line with water, pressurizing it to a predetermined level and maintaining the pressure for a period. Based on the results, detected anomalies in pressure, volume and density can be a precursor to leaks.

Critics however, argue and have quite effectively demonstrated that the hydrostatic tests lack the ability to monitor ongoing corrosion or cracking and that the high pressure environment can exacerbate previously small defects, increasing risk of future rupture.

Smart pigs for detecting large cracks and corrosion

Unlike hydrostatic testing, which is often conducted on pipelines for acceptance testing or for pipelines recently rehabilitated, pigging is the more commonly accepted method of testing pipeline integrity.

While newer “smart” pigs have an excellent reputation for accuracy, their efficacy is often limited to detecting corrosion and cracking that exceeds the threshold for detection of the technology.  Small corrosion pits and cracks, especially cracks grouped in a colony, can pose a challenge to most conventional ILI pigging devices.

The various ILI technologies are sensitive to axial or circumferential defects, and each has limitation for minimum aspect ratios or cross sectional wall loss area before the ILI tool can report the anomaly.  It is also possible to have cracks and wall loss pits that are in close proximity to girth welds, long seams, and other features in the pipe, which can mask the defect, preventing the ILI tool from properly identifying and sizing.  As a result, it is possible to have leaking cracks and corrosion pits that are too small to be sized and reported from conventional ILI.

Not all lines are piggable

Some pipes are more suitable for pigging than others. While most oil and gas transmission lines were built in long straight sections suitable for pig runs, sections with small diameter pipe and small bend radius pipe configurations can limit many ILI tools.  Lines with expansion loops and miter bends, and in the case of natural gas lines, those with reduced port valves, are factors that can prohibit or restrict the traversing of inline tools.

Mass balance measurement and other leak detection tools

To make up for the limitations of conventional ILI technologies, operators often deploy measurement methods and leak detection technologies to complement their integrity programs.

Mass balance is a means of detecting leaks by measuring the mass of product entering the pipeline compared to the mass exiting the pipeline. The limitation for detecting small leaks is the sensitivity of the mass meters being used (2-4% accuracy for conventional orifice meters and 0.25% for turbine meters), and the fact that the product temperature and pressure changes as it moves through the pipeline.

While mass balance is a means to determine leaks, it is also recognized that making actual measurement of mass from volume (through a meter) at different temperature and pressure going in versus coming out of the pipeline, in real time, is difficult, and not very precise or sensitive to small leaks.

As a result, a leak has to release more product than the total tolerance of the mass balance system before a positive leak/release event is alarmed.

Acoustic leak detection

Minute cracks are often preliminary indicators of potential small leaks that produce acoustic emissions at levels often unrecognizable over background noise.

Acoustic leak detection can be conducted with geophones/hydrophones, comparators and acoustic fiber optic techniques, and each of these acoustic tools is subject to different background noise limitations to determine leak detection thresholds.  Not only can these tools have limitations to prevent small leak detection, the expense from installing permanent acoustic systems may reduce the practicality of these technologies.

Emerging technologies on the horizon

To complement hydrostatic testing, conventional pigging tools, and leak detection technologies, the oil and gas industry is evaluating a growing number of emerging external confirmation of containment technologies. These include vapour-sensor systems, hydrocarbon-sensing cables that change in the presence of hydrocarbons, internal pressure wave based tools and fibre-optic based systems that detect temperature changes and acoustic signals associated with leaks.

While these technologies offer hope for more precise surveys, they have yet to be universally accepted or proven. Many are still under development and often require economically impractical installation requirements.

However, there is an innovative, multi-sensor ILI platform that has been used in integrity management programs since 2006, gaining the attention of major pipeline players who have tested the platform, which has now been used on over 25,000 kilometers of pipeline in total.

Introducing SmartBall® technology for Oil & Gas pipelines

To provide a realistic snapshot of a pipe’s condition, many proactive operators are deploying SmartBall technology,  a free-swimming multi-sensor tool for long inspections of piggable and difficult to pig liquid and gas pipelines 4 inches and larger. This advantage makes the ball-shaped tool an excellent choice for traversing not just standard diameter pipes, but for smaller diameter liquid lines and for gas pipelines with loops and frequent sharp bends and heavy wall fittings.

During an inspection, the SmartBall sensors collect acoustic, pressure, temperature, magnetic and inertial data from inside the pipeline.

Primary applications for the SmartBall tool

SmartBall surveys can be conducted independently, at regular intervals, as part of a routine pipeline integrity management program, or as a value-add to inspection programs along with hydro-testing, ILI, or direct assessment.

The tool is launched and retrieved at existing pig traps and is tracked using proprietary acoustic receivers and/or Armadillo pig tracking boxes (AGMs). The location data from acoustic receivers and tracking boxes is used during data analysis to locate any anomalies.

SmartBall technology has three primary applications, and the multi-sensor tool can provide a variety of pipeline data.

1. Confirmation of Containment

Regular confirmation of containment surveys are an important part of integrity management as leaks are often a preliminary indicator of pipe failure.

Unlike conventional leak detection systems, confirmation of containment with SmartBall supplements these systems. The SmartBall tool directly passes leaks, and is therefore capable of detecting losses as small as 150 mL/min, which can be several orders of magnitude more sensitive than conventional methods.

SmartBall surveys can also complement regular ILI surveys by addressing potential pinhole anomalies that have aspect ratios below the reporting threshold of ILI systems.

2. Pressure and Temperature profiles

As the SmartBall is rolling and not sealing against the pipe ID, as conventional pigs do, the tool can also record precise pressure and temperature profiles. The SmartBall platform can be deployed in gas pipelines, where pressure and temperature profiles can be integrated into flow models to assess the points where water vapor may condense out of the gas.

The tool can also be used to assess the point where high temperatures from pump or compressor output may have affected the pipe coating, as well as in settings to validate and improve SCADA and mass balance systems.

3. Pipe Wall Assessment and Inertial Mapping

During inspection, the SmartBall Pipe Wall Assessment (PWA) tool collects magnetic data that can provide a screening of the pipe wall for stress resulting from features like large cracks, large wall loss, dents and points of excessive loading.  The test can also complement hydrostatic testing, as it can survey the pipeline before and after hydro-tests to identify stress that is indicative of pressure reversals.

In addition, the SmartBall PWA tool can produce a girth weld and joint tally for the pipeline, as well as can confirm locations of bends and general geometry of the pipeline.

Helping operators make better decisions

Admittedly, SmartBall is not designed to compete with high resolution technologies like Magnetic Flux Leakage (MFL), which can provide detailed wall loss data.

What SmartBall can do is complement other integrity tools by providing additional data sets to ensure pipeline integrity. In a single deployment, it can detect anomalies associated with pinhole leaks and stress that doesn’t necessarily involve wall loss; e.g. geotechnical strains.  It can also detect change in pressure and temperatures.

Ultimately, the SmartBall tool can help capture enough data to confirm the integrity of the pipe and give operators enough microscopic knowledge to make better, informed, risk-based decisions on the health of their pipelines.

City of Montreal Skyline

The City of Montreal believes that the best medicine is preventative medicine, especially as it applies to its water network.

Montreal has an impressive water system that supplies drinking water to a population of nearly 1.9 million people. Since 2002, the historic city, the second largest metropolis in Canada, began a long-term major rehabilitation of its extensive network of water main (770 kilometers) and distribution pipes (4,600 kilometers).

In 2015, as part of a pre-emptive program to reduce loss of non-revenue water, the City partnered with Pure Technologies (Pure) to conduct an ongoing, three-year leak detection survey on a series of critical pipes within its network, several of which are located in the downtown core.

Inserting tools through inspection hole in a street

Stopping small leaks from developing into major breaks

The City recognized the value of detecting leaks, however small, to prevent these from developing into greater problems. Compared to a major pipe rupture, which can cause catastrophic damage and incur immediate excavation and costly repairs, small leaks are less obvious at first, and can seep underground for some time without obvious detection.

In addition to physical losses of water caused by a series of small leaks, the escaping non-revenue water can eventually erode the surrounding soil making the area more prone to washouts or sinkholes, a major headache especially in densely populated areas. Unplanned excavations to repair unforeseen leaks can also erode consumer confidence in a public utility.

Leak detection strategy includes Sahara acoustic video inspection

For its multi-year leak detection program, the City requested Pure to deploy its highly reliable and precise Sahara® acoustic video inspection on 46 kilometers of pipelines chiefly in the downtown core. The pipeline sections consist of bar wrappedsteel and cast iron pipe.

The Sahara platform is modular, and can be configured with a variety of sensor tools to perform the condition assessment. This includes an acoustic sensor to perform leak and gas pocket detection, a high-resolution video camera to assess internal pipe conditions, and an electromagnetic sensor to identify stress in the pipe wall.

Because the Sahara tool is drawn by product flow via a small drag chute, and is tethered to a data acquisition unit on the surface, it gives the operator close control to confirm suspected leaks, gas pockets and other pipeline anomalies. The tool can visually confirm pipe irregularities, continuously recording, allowing for both real-time and post-processing analysis.

Workers during Sahara device insertion

 

Data used to shape urgency and timing of rehabilitation efforts

For the Montreal project, the purpose of the Sahara inspection was to assess the condition of the pipeline by identifying and locating leaks, pockets of trapped gas and to identify larger visual anomalies utilizing Closed Circuit Television (CCTV) footage collected during the inspection. The data would help shape the rehabilitation urgency and timing.

To date, a total of 13.2 kilometers have been assessed. Analysis of the data identified eight (8) leaks and zero (0) gas pockets in the pipeline sections inspected. The Sahara sensor was tracked above ground using the Sahara Locator device to pinpoint in real time the location of any potential leaks or anomalies.

The leak detection program has not been without challenges. Valve operations were needed to achieve required pressure flows, and mobilization had to be based on hours of demand, and inspections conducted during those hours.  A number of tight chamber clearances meant the creation of new insertions taps, and because of the urban environment, markings had to be precise, and crews had to deal with traffic issues.

Despite challenges, the assessment is proving its worth from a verification viewpoint, and the leaks have been either repaired or addressed for prioritization. The current program is scheduled for completion by 2017.

With its pre-emptive leak detection program, the City is Montreal is a great example of a smart water manager taking proactive efforts at keeping its network in healthy shape.

The most common form of pipeline integrity used by oil and gas pipeline owners is inline inspection (ILI). Inspection pigs are widely used to clean pipelines, as well as identify areas of damage along the pipe wall to ensure the safe delivery of energy products.

Historically, once a pig is deployed in a pipeline, a technician confirms the tool’s arrival time at various tracking locations throughout the planned inspection distance. Once the tool has passed each location, it is out of sight until it reaches the next tracking point. However, recent technological advancements in tracking technology now allow for pigs to be tracked remotely throughout an entire ILI run.

Remote tracking combines the use of above ground markers (AGMs) and Remote Tracking Units (RTUs) that are deployed before an ILI run is scheduled to take place and are used to track the pig from a central location. When a pig approaches a tracking site, the RTU and AGM are activated to track the tool, which eliminates the need to have a field technician to be on site.

Consistent Live Tracking

PureHM has developed a web-based software called LiveMap that tracks a pig throughout the entire ILI run. LiveMap provides real-time updates via email or SMS with the pig’s location, speed, and estimated time of arrival to ensure that there is better visibility for stakeholders during a project. This advanced technology mitigates the risk of unexpected challenges in an ILI run, such as a stuck pig or speed excursion.

Live tracking offers more control throughout an inspection, and can help prevent costly incidents such as lost pigs by providing accurate information on a pig’s location. A lost pig can interrupt or stop product flow in a pipeline, and can lead to pipeline damage and unforeseen service disruptions.

LiveMap drawing

During an ILI run, the time and speed information collected each time the pig passes the AGM is updated and presented in LiveMap. In traditional legacy tracking runs, this is completed and reported by the field tracker, while in remote tracking runs this is completed automatically with a defensible record of the passage.

To learn more about remote tracking, download PureHM’s pig tracking white paper.

Download full PDF

Hamilton sign

In late 2015, the City of Hamilton, Pure Technologies (Pure) and Robinson Consultants worked together to perform an external investigation of a pipe section in the Woodward Greenhill Transmission Main (WGTM) to gain understanding of what was causing degradation in a specific geographical area.

A 2014 condition assessment performed by Pure had identified a cluster of damaged pipes on the WGTM, which is comprised of prestressed concrete cylinder pipe (PCCP). Pure used electromagnetic (EM) inspection technology to identify which pipes in the WGTM had broken prestressing wires, a sign of deterioration in PCCP. When prestressing wires break, the pipe loses compression. When enough wires break the pipe becomes at risk of failure.

Understanding the root cause of why pipes deteriorate

Pure’s condition assessment of the WGTM included finite element analysis (FEA) to determine the number of broken wires a pipe can safely operate at given the pressures of the pipeline. Although each pipe reported with broken wires had total wire breaks well below the threshold, and not in any immediate need of rehabilitation, further investigation of the pipeline was undertaken to understand the root cause of the degradation.

The City of Hamilton’s pipeline management plan is comprehensive, going beyond identifying and managing damaged pipe sections. By understanding why the pipes are deteriorating, expectations on future degradation can be made.

The investigation included testing the soil and mortar to determine if aggressive soil conditions were contributing to the distress, and confirming the pipe properties and actual number of wire breaks, factors key to the structural analysis of the distressed pipe.

External EM scan confirms correct pipe excavated

On October 20, 2015 Pure performed an external investigation on one of the pipes identified with wire breaks. Pure’s external investigation included an external EM scan to confirm the correct pipe was excavated. This was accomplished by comparing the data from the external EM scan to the data from the internal EM data collected from the 2014 inspection. The comparison confirmed the correct pipe was found.

The next step was an external and visual sounding inspection of the exposed pipe. The mortar was inspected for cracks, spalls, corrosion staining and other signs of distress that would indicate advanced deterioration. None of these signs were found.

Process for verifying number of broken wires

The process of verifying the number of broken wires on PCCP involves removing an approximately 2-inch wide strip of mortar across the length of the pipeline to expose the prestressing wires, and using a multi-meter to measure the electrical resistance from wire to wire (this process is specific for PCCP without shorting straps). If an electrical discontinuity is identified, it confirms that a break exists between the two points of contact. Upon completion of the tests, the mortar is patched to protect the wires and prepare the pipe for burial.

Workers with measurements tools

The electrical continuity measurements on the exposed pipe section in the WGTM confirmed the two regions that were identified by the electromagnetic inspection. No other wire breaks were found across the pipe length.

 

 Comparison Of Estimated Versus Actual Wire Breaks
Estimated Position Actual Position Estimated No. of WB Actual No. of WB
4 feet 3 feet 5 2
8.5 feet 8-8.5 feet 10 6

 

Results used to recalculate FEA analysis

The results of the investigation were used to recalculate the FEA analysis, adding to a slight increase in the number of wire breaks that the pipe can withstand under pipeline pressures. Ultimately the findings concluded that the pipe can remain in service with no repair or changes to operating pressures.

The City of Hamilton’s condition assessment program for PCCP pipe is an example of their comprehensive approach to pipeline management. Beyond locating the damage, the City strives to understand the root cause. The use of the EM inspection technology allows the City to pinpoint damaged pipe sections. FEA analysis provides a means for determining if a pipe requires rehabilitation.

For this project, further investigation through external testing will provide insight into the root cause of pipe deterioration (the results of the soil and mortar testing will be presented by Robinson Consultants at a future date). This project showed how collaboration between the City, Pure Technologies, and Robinson Consultants resulted in a comprehensive condition assessment of one of Hamilton’s critical watermains.

Metallic pipes have a long history in distribution systems throughout North America, with cast iron and carbon steel making their debut in the early 1800s. In many states, pipelines deploying the early metal are still in service, including the cast iron water main buried in 1831 beneath what is now Greenwich Village.

Risk prioritization as a starting point

Before undertaking any metallic pipe inspection, a utility should first complete a risk prioritization of all their buried assets, factoring in a variety of consequence of failure (COF) and likelihood of failure (LOF) variables to determine the highest/lowest risk pipelines. A distribution pipe buried in a cornfield probably has a lower risk profile than a water main buried under a children’s hospital.

This first step in risk analysis is critical, and can help determine a prioritized strategy. The higher the risk, the more an operator requires reliable information for an action plan to replace, rehabilitate or inspect the pipes further to gather more precise data.

Using asset risk to guide the management strategies, an operator can feel confident about implementing the right approach, at the right time, with the lowest financial impact. Overall, this strategy ensures long-term service, reliability and safe operation.

Match the technology and inspection method with the risk

This initial process also allows operators to choose the most appropriate inspection method based on different pipe material and operational requirements, including lack of redundancy.

If the analysis ranks the mains as medium to high-risk pipes, it makes sense to utilize medium to high-resolution inspection technologies. High risk pipes are probably more expensive and more difficult to replace, and probably affect more people if taken out of service.

 

Medium Resolution Technology

Pipeline Inspection and Condition Assessment Services

PureEM™

PureEM technology represents a form of non-destructive testing that provides a snapshot of the pipeline`s condition by inducing electric currents/magnetic fields within the pipe to measure an electromagnetic response. By creating these fields, PureEM data identifies specific areas of the pipe wall with large EM anomalies. In the case of metallic pipes, these anomalies typically represent broad areas of corrosion.

Typically, metallic pipes are first assessed with a prescreening tool – including inline leak detection and pipe wall assessment – followed by PureEM testing, using one of three platform tools. This multi-tool approach provides the operator with a variety of condition information that can help inform renewal decisions.

With PureEM manned inspection tools, field technicians have the option enter the pipeline with a PureEM inspection tool (e.g. push cart, bicycle) and traverse the length of the pipeline, inspecting for damage. The tool can be used in dewatered water and wastewater pipelines.

Free-Swimming Pipeline Inspection

PipeDiver®

When configured with PureEM, the free-swimming PipeDiver tool is an effective medium resolution tool to assess areas of damage along a pipeline that is live or can’t be taken out of service due to a lack of redundancy or operational constraints. It is ideal for metallic pipes with a higher consequence of failure, since the tool operates while the pipeline remains in service.

PureRobotics™ – Pipeline Inspection

PureRobotics™

Pure`s long range, multi-sensor robotic inspection vehicles are capable of conducting PureEM inspections on steel and ductile iron pipes. The robotic vehicle can be used in depressurized and partially dewatered and wastewater pipelines.

No one solution for every pipeline

Every pipeline has a unique set of conditions, which is why there is no one silver bullet that works across the board.

However, if a utility has a strong understanding of the risk and operational conditions of different areas in their system, an appropriate and defensible inspection plan can be developed. This process allows operators to develop a sustainable long-term strategy for managing their critical buried assets.

Critical large-diameter water transmission mains frequently run beneath city streets in busy urban environments. Like the majority of water infrastructure across North America, these pipes are reaching the end of their design life. However, pipelines in urban environments pose a significantly greater risk and challenge to water utilities.

These pipelines are high-risk because of their high consequence of failure; if a pipe beneath a busy downtown street fails, the repair costs can quickly escalate and the failure causes a massive disruption to businesses and commuters. In some cases, failures in urban environments have cost utilities upwards of $5 million to remediate. A failure not only carries a high repair bill, but contributes to a negative public perception of the utility which can harm consumer confidence and lead to negative public relations.

With such high risk, utilities often prioritize these mains ahead of those with lower consequence of failure. However, because these mains are located in high-traffic areas, assessing them is far more challenging than assessing a linear main in a rural area.

Dealing with above ground obstructions, commuter delays and a lack of access points means that operators need to have close control over inspection technologies. In addition, the technology must provide the best possible information to allow for accurate repair and excavation decisions.

Like other major metropolitan areas, the City of Montréal has aging pipeline infrastructure that runs through its downtown core. In Montréal – one of the oldest cities in North America – this infrastructure is very old and beginning to reach the end of its design life. In order to proactively identify problem areas in its Prestressed Concrete Cylinder Pipe (PCCP) assets, the City is in the midst of an inspection program using advanced non-destructive technologies. In total, the City will assess the condition of over 40 kilometers of PCCP by 2015.

In the majority of cases, assessing the condition of assets to identify problem areas has high value for utilities, since the majority of pipelines have remaining useful life, despite their age. This allows for selective rehabilitation in favour of full-scale replacement. This is particularly important in urban areas, since excavation costs are higher and more disruptive in urban environments.

PureRobotics platform

The PureRobotics platform remains tethered to the surface during inspection. 

Pipe with damaged areas

Verification showed large areas of damage to both the prestressing wires and steel cylinder.

Related Topics

For a large portion of the condition assessment, the City is using the PureRobotics™ platform, since it is ideal for challenging urban environments. The tool remains tethered to the surface during inspection and is controlled by an operator. It also features live high definition video to observe internal pipe conditions. These features allow the City to see internal pipe conditions and closely verify areas with potential problems.

In addition, the tool identifies broken prestressing wire wraps in PCCP. As PCCP ages, the prestressing wires, which make up the main structural component, begin to break due to a number of factors.

The presence of broken wires in PCCP is the main indication that the pipe will eventually fail. Unlike metallic pipe materials that typically fail after a long period of leakage, PCCP is prone to sudden failures when too many wires break in one area. The diagram below demonstrates how PCCP typically fails.

How PCCP Fails

Recently, the City has completed the assessment of just over 17 kilometers of its urban PCCP assets with diameters of 600, 750 and 900 millimeters (24, 30 and 36 inches). Of the 2,798 pipe sections assessed in this 17 kilometers, only 97, or 3.5 percent, have shown evidence of distress. This is slightly below the industry average of 5 percent of pipe sections with distress.

Using condition assessment, the City has been able to identify isolated distress on its critical urban mains, while leaving pipeline assets with remaining useful life in operation.

After completing the initial phases of condition assessment, the City has excavated certain sections of pipe for validation of the inspection results, as well as repair of any damage.

Both the excavation locations and presence of distress have been very accurate. This has allowed the City to repair isolated pipe sections, which restores the overall condition of the pipeline. This will help to prevent failures that would significantly disrupt day-to-day life in the city.
In addition, the City now has a baseline condition of all of the assessed pipelines, which helps in the development of future capital planning for monitoring or re-inspection.

By proactively assessing its PCCP mains, the City of Montréal is taking steps to prevent pipe failures, while allowing for more fiscally responsible asset management in the future.

 

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PureRobotics™ – Pipeline Inspection

Robotic Pipeline Inspection

PureRobotics uses powerful modular robotic pipeline inspection systems that can be configured to inspect virtually any pipe application 12-inches (30.5 centimeters) and larger.

Assess & Address Pipeline Management Program

Assess & Address Pipeline Management Program

Pure Technologies is helping utilities manage their buried infrastructure through its Assess & Address which can often be implemented for only a fraction of the capital replacement cost.

Technical Paper

Beyond the Wires: A Sustainable Approach to Prestressed Concrete Cylinder Pipe Management

While evaluating wire breaks are an important part of PCCP management, it is important to acknowledge additional factors beyond wire breaks. By acknowledging additional condition factors, limitations of wire break assessment, and considering other rehabilitation approaches, there may be a more sustainable PCCP management approach (or combination of approaches).

Abstract

Acoustic leak detection inspection tools have become a common technique to identify minute pipeline leakage before the leak and the defect producing it can become a larger problem or even a rupture level event. While these inspection tools only identify small defects once they reach the through wall stage and result in leakage, they can be an effective means of demonstrating the pressure tightness of a pipeline and ruling out the presence of through wall defects that are below the detection threshold of other ILI inspection tools; in so doing finding a way into both the leak detection and pipeline integrity toolboxes.

Enbridge Pipelines owns and operates a 12” pipeline that transports crude oil over 870KM. A majority of the line resides in permafrost conditions in a remote region, thus the window for inspections or work to be done on the pipeline is limited. Additionally the pipeline consists of long segment lengths between traps, which traverse multiple water crossings and experiences large changes in elevation. Therefore, availability, scheduling, and transport of inspection equipment are critical. The SmartBall® leak detection tool was selected for a twofold purpose: to test the technology’s capabilities, and to inspect the line specifically for any leaks.

Inspection of 3 segments of the 12” pipeline provides some unique challenges to inspection providers, requiring tools with up to 12 days of operational run-time capability and the ability to operate in product temperatures as low as -15 degrees Celsius. The generation of SmartBall® tools at the time did not have the run time and data capacity required to inspect the entire length of each of the pipeline segments. As a result, Enbridge and Pure Technologies collaborated on the development of a custom, long duration, high data capacity, SmartBall acoustic leak detection tool specifically for the 12” pipeline application.

Authors

  • Laura Seto, P.Eng., Pipeline Integrity Department, Enbridge Pipelines Inc., Calgary, AB, Canada
  • Tim Ross, P.Eng., Pure Technologies Ltd., Calgary, AB, Canada

Asset management strategies provide utilities with information on their buried assets; knowing what assets they have and when they will need rehabilitation is crucial for planning and fiscally responsible decision making.

A number of recent reports have highlighted the need for better asset management practices in the water and wastewater industry.

Black & Veatch’s Strategic Directions in the U.S. Water Utility Industry Report, released in 2012, highlights the need for asset management programs that streamline all the information and planning in a system.

Field Data Collection

The Canadian Infrastructure Report Card 2012 also highlighted the need for better asset management among Canadian utilities. The report found that many municipalities lack the internal capacity and resources to accurately assess the state of their infrastructure; many respondents had limited data on water treatment and pumping facilities and the condition of buried pipeline assets.

In order to help utilities with asset management master planning, Pure Technologies is now offering the PureNET™ asset management software which allows water utilities to manage water infrastructure data more effectively. PureNET links data from existing utility databases such as billing systems, hydraulic models, workload programs and maintenance management systems.

PureNET also has the ability to merge data from Pure’s pipeline inspection and monitoring technologies, it is fully integrated and extracts the most relevant information from each database, making asset management less complex and time consuming.

Initial case studies of utilities using PureNET show that the implementation of the system within a utility’s pipeline network can increase financial earnings by 3.5 percent.

PureNET helps streamline planning and decision making by establishing maintenance priorities, budgets, and planning of future projects, as well as providing information on the condition and useful life of a utility’s infrastructure. The software moves utilities from reactive to proactive asset management and bridges the gap between engineering and finance.

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Pipeline Asset Management Software

PureNET™ – Integrated Non Revenue Water and Asset Management Software

In order to help utilities manage all aspects of their complex water and wastewater systems, PureNET™ allows utilities to manage their infrastructure data more effectively.

Assess & Address Pipeline Management Program

Assess & Address Pipeline Management Program

Pure Technologies is helping utilities manage their buried infrastructure through its Assess & Address which can often be implemented for only a fraction of the capital replacement cost.

Bloomberg TV Story

Initially, owners and operators perceived that once a pipe was constructed and buried, inspecting pipelines was not necessary as long as they were in proper working order. But with the trend of urbanization and development, the risk of operating these pipelines became greater, as leaks or failures can significantly threaten communities and the environment.

The challenge of managing aging pipelines that were not built with the thought of inline inspection is daunting. To best mitigate risk, oil and gas operators should use a multi tool approach that incorporates both real-time and survey-based condition assessment technologies.

SmartBall® leak detection for oil and gas pipelines is an innovative tool that can effectively compliment integrity programs. The tool identifies acoustic anomalies associated with leaks which differ from anomalies created by other sounds and pipeline features. SmartBall technology is highly sensitive and can identify leaks that aren’t typically found using other systems.

 

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Pipeline Leak Detection Systems

Pipeline Leak Detection Systems

Highly accurate inline leak detection systems that can detect leaks and gas pockets in operational pipelines. These systems are used primarily on larger diameter water and wastewater transmission mains of all materials as well as oil & gas pipelines.

Technical Paper

Development of a Long Duration, Free Swimming, Inline Acoustic Leak Detection Inspection Tool

Acoustic leak detection inspection tools have become a common technique to identify minute pipeline leakage before the leak and the defect producing it can become a larger problem or even a rupture level event. While these inspection tools only identify small defects once they reach the through wall stage and result in leakage, they can be an effective means of demonstrating the pressure tightness of a pipeline and ruling out the presence of through wall defects that are below the detection threshold of other ILI inspection tools; in so doing finding a way into both the leak detection and pipeline integrity toolboxes.