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Page 1

Di�cult To Pig And To
Inspect O�shore Pipes
Exclusive white paper by Innospection

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Process safety

The road to high reliability

Business Intelligence for the Offshore Industry

In December 2009 veteran drilling executive Kevin
Lacy exited as BP’s vice president for drilling and
completions in the Gulf of Mexico. At the time he
saw significant planned organizational changes, a
risk-heavy set of deep water wells, along with
pressure to reduce costs. Four months later came
the Macondo blow-out. Here he explains why oil
and gas is far from being a “high-reliability” sector
yet, and how we might start moving in that
direction.

Kevin Lacy, Global Senior Vice
President for Drilling and
Completions, Talisman Energy
(retired)

Innospection is a specialist in electromagnetic inspection technologies such as Eddy Current
and SLOFEC™. We have successfully delivered advanced non destructive testing solutions to
the worldwide process industries such as the Oil & Gas (on- & o�shore) Industry, Refineries,
Chemical Plants, Power Plants and other process industries for over 10 years. With
experienced inspection engineers and an innovative R&D team, Innospection has created an
enviable reputation for applied expertise, quality and e�ective delivery within the industry.

http://ppsa-online.com/

Process safety

The road to high reliability

In December 2009 veteran drilling executive Kevin
Lacy exited as BP’s vice president for drilling and
completions in the Gulf of Mexico. At the time he
saw significant planned organizational changes, a
risk-heavy set of deep water wells, along with
pressure to reduce costs. Four months later came
the Macondo blow-out. Here he explains why oil
and gas is far from being a “high-reliability” sector
yet, and how we might start moving in that
direction.

Kevin Lacy, Global Senior Vice
President for Drilling and
Completions, Talisman Energy
(retired)

In association with Subsea Integrity Conference (SSIC),
Europe 2014

Page 2

When I left BP I was concerned there might be problems, but when I saw Macondo unfold on
the news I was aghast. I couldn’t have predicted anything of that magnitude. Prior to that I
would have said a major catastrophe in deep water might have been measured, cost-wise, by
around a billion dollars. If somebody said ten billion I might or might not have debated it. For
something to come in at forty billion was, and is, just incredible.

When I was deposed as part of the hearings in the Macondo incident the big question I kept
getting asked was, did anyone tell me to cut corners or sacrifice safety in the interest of cost?
And the answer, obviously, was no. It would be rare to find a senior leader give a directive to
sacrifice safety or to cut corners at the expense of keeping people safe.

There was, as I stated in my deposition, “tremendous pressure” to reduce costs at BP. Part of a
senior leadership role is to manage that pressure so it doesn’t distract people or get in the way
of sound decisions. It was this pressure on costs combined with the inherent risk of running
eight to ten deep water rigs that gave me concern in light of the proposed changes in the
organization and the new people being placed in key roles. In a time of great change with many
new managers we know that people will not be comfortable in raising concerns – it is basic
human nature.

The changes during that time were part of a bigger corporate reorganisation and I worried that
it was all too much. I suddenly found myself being told that there was not a role for me in the
new organization. I signed an agreement regarding my departure and was obligated, until parts
of my deposition were made public, not to speak of the circumstances of my departure. About
a week later Talisman Energy called and I left BP GOM in early December 2009.

employer Chevron had benchmarked very well. I’d announced my retirement from Chevron in
2006 not knowing where I was going next and got a call from a recruiter representing BP. The
initial role was to provide western hemisphere oversight. In 2007, they asked me to lead a study
on the Gulf of Mexico drilling and completion (D&C) operations, a business unit that was having
challenges. Halfway through the study they asked me to take over the D&C organization as well
as the Health, Safety and Environment group for the GOM.

reorganised the group in 2008 and, as a consequence, saw a dramatic turnaround in
performance in that year and the next. We went from bottom in the internal performance
league – in terms of safety, hitting capital budgets, production ahead of schedule and so forth –
to the top.

I had ongoing concerns with the risk of deep water drilling operations, concerns that started
back when I was at Chevron. They stemmed from just too many things going on
simultaneously within the industry. The deep water rig fleet expanded by close to 300% over
several years along with much turnover between drilling contractors and so I worried about the
erosion of the level of competency that we were accustomed to, particularly at the driller and
tool pusher levels.

These deepwater wells are very complicated. There are downhole conditions that even very
intelligent people struggle accurately to asses. The time when you had a drilling foreman who
has seen everything and knows what to do in every situation is long gone.
The challenge with process safety and well control now is that the major incidents are so
infrequent that there is a general sentiment that these things don’t happen, or won’t happen –
unlike with personnel safety, where there’s enough going on for the risk to be visible and in
people’s minds.

When I left BP I was concerned there might be problems, but when I saw Macondo unfold on
the news I was aghast. I couldn’t have predicted anything of that magnitude. Prior to that I
would have said a major catastrophe in deep water might have been measured, cost-wise, by
around a billion dollars. If somebody said ten billion I might or might not have debated it. For
something to come in at forty billion was, and is, just incredible.

When I was deposed as part of the hearings in the Macondo incident the big question I kept
getting asked was, did anyone tell me to cut corners or sacrifice safety in the interest of cost?
And the answer, obviously, was no. It would be rare to find a senior leader give a directive to
sacrifice safety or to cut corners at the expense of keeping people safe.

There was, as I stated in my deposition, “tremendous pressure” to reduce costs at BP. Part of a
senior leadership role is to manage that pressure so it doesn’t distract people or get in the way
of sound decisions. It was this pressure on costs combined with the inherent risk of running
eight to ten deep water rigs that gave me concern in light of the proposed changes in the
organization and the new people being placed in key roles. In a time of great change with many
new managers we know that people will not be comfortable in raising concerns – it is basic
human nature.

The changes during that time were part of a bigger corporate reorganisation and I worried that
it was all too much. I suddenly found myself being told that there was not a role for me in the
new organization. I signed an agreement regarding my departure and was obligated, until parts
of my deposition were made public, not to speak of the circumstances of my departure. About
a week later Talisman Energy called and I left BP GOM in early December 2009.

employer Chevron had benchmarked very well. I’d announced my retirement from Chevron in
2006 not knowing where I was going next and got a call from a recruiter representing BP. The
initial role was to provide western hemisphere oversight. In 2007, they asked me to lead a study
on the Gulf of Mexico drilling and completion (D&C) operations, a business unit that was having
challenges. Halfway through the study they asked me to take over the D&C organization as well
as the Health, Safety and Environment group for the GOM.

reorganised the group in 2008 and, as a consequence, saw a dramatic turnaround in
performance in that year and the next. We went from bottom in the internal performance
league – in terms of safety, hitting capital budgets, production ahead of schedule and so forth –
to the top.

I had ongoing concerns with the risk of deep water drilling operations, concerns that started
back when I was at Chevron. They stemmed from just too many things going on
simultaneously within the industry. The deep water rig fleet expanded by close to 300% over
several years along with much turnover between drilling contractors and so I worried about the
erosion of the level of competency that we were accustomed to, particularly at the driller and
tool pusher levels.

These deepwater wells are very complicated. There are downhole conditions that even very
intelligent people struggle accurately to asses. The time when you had a drilling foreman who
has seen everything and knows what to do in every situation is long gone.
The challenge with process safety and well control now is that the major incidents are so
infrequent that there is a general sentiment that these things don’t happen, or won’t happen –
unlike with personnel safety, where there’s enough going on for the risk to be visible and in
people’s minds.

DIFFICULT TO PIG AND TO INSPECT OFFSHORE PIPES
K. Reber, Innospection Germany GmbH, Stutensee, Germany
S. Hartmann, Innospection Ltd., UK
A. Boenisch, Innospection Ltd., UK

Introduction

When it comes to a fast, non-intrusive, complete and meaningful inspection of an o�shore
pipeline in-line inspection (ILI) has been the method of choice for several decades now. Howev-
er, not all pipelines, piping or other tubular structures can be inspected with in-line inspection
tools (pigs). The method is usually limited to looping flow lines or export pipelines, specifically
designed for ILI operation. The remaining structures are often summarized under the buzzword
“non-piggable”.

The typical ILI viewpoint is to consider the piggability under either the aspect of pipeline design
or pipeline operation. Typical piggability issues in pipelines under pipeline design aspects are
launching/receiving facilities, bends, and internal obstructions. The other aspects are opera-
tions-related. ILI may be impossible due to too high/low flow, too high temperature and other.
In both cases ILI solutions can still be conceived and realised by either changing the pipeline or
by adapting the pig. The latter is the technically more interesting solution for service providing
companies. ILI providers are busy in designing and already o�er tools for multiple diameters, for
bi-directional operation and tools with special insertion techniques. Also there are many
solutions available that use a cable operated tool and/or a crawler type tool. Discussions on
solutions for unpiggable pipelines usually focus on these types of solutions.

There still remains an area of inspection tasks that can be summarized under “Not at all pigga-
ble”. For either technical or financial reasons, a pig-like solution may still remain unfeasible. In
some cases the involved technical risk may also convince the involved parties to refrain from
any ILI adaptation. In these cases either key-hole solutions or external inspection may remain
the only option. The distinction between a key-hole solution and a pig-based inspection can be
made by the aim to reach a 100% coverage in the latter case. For other inspection types a lower
inspection coverage is usually accepted.

In addition to these topics there is another category of reasons, why a pipeline may be consid-
ered unpiggable. This concerns problems that are due to the available inspection technology
and the inspection task. Other authors have named piping su�ering from this problem rather
uninspectable than unpiggable. This accounts for the fact, that a pigging operation is not
related to an inspection, but the passing of a pig. If a pig can pass, but the pipeline is not
inspected, because available inspection techniques do not detect defects, the pipeline is
uninspectable. Figure 1 is giving an overview of the di�erent categories of inspection.

Page 3

What I think we can conclude about Macondo is that the event itself was caused by very basic
mistakes in well control but the consequence, and the size of the consequence, was a result of
deepwater conditions. Blowouts have always been a concern but this level of consequence has
got to be completely unacceptable in our industry and cannot just be dismissed as “bad luck”.

People versus process

The public reaction to Macondo was standard: blame the individuals, and write new processes
(along with hiring new frontline people to enforce them). But I believe the response needs to be
deeper than finding a scapegoat and finding a process gap. The lesson I take from this is that
there are three necessary parts to building a process safety culture. One is leadership, one is the
actual process or standards, and then there is the culture itself, how we work. Those three
things should work together dynamically and reinforce each other.

The problem is, it’s infinitely easier, especially for engineers and technical people, to write a new
process. But we have enough processes, and it is pretty rare these days to find a truly

writing a new one we have to ask the tough questions. Why was it not being used? Does the
leadership know it well enough to talk about it with the frontline, to reinforce it?

Culture, behaviour, how we talk to each other, and about what – for engineers that’s all pretty
fuzzy, so the reflex is to create more process, more regulation, more audits, and beefed-up
equipment.

highly evolved and embedded. The question is always: did the mechanic, the pilot, the crew
follow the process? That’s where we have to move to. I’m very skeptical about new layers of
procedure being added when basic well control procedures, if followed, would work very
adequately to prevent another Macondo.

Do we have a culture problem?

North American culture wants less process, less legislation. There is an adversarial mindset
among industry players and between industry and the regulator. The values can be expressed
by statements like ‘less is adequate’, and ‘experience is a better guide than a highly codified
process’. There is a strong independent streak, as well. The concept of communal responsibility
that you see in parts of Europe, for instance, is foreign.

I think this has consequences. It is no surprise to me that onshore personal safety performance
in North America is among the worst in the world. I think the prevalent culture in oil and gas in
North America does present challenges but, having said that, all cultures do. I’ve worked in 15

norms and values and try to hitch those to your engine of change.

The strongest influences on culture are the regulatory environment, company leadership, and
peers. In the North American context a salient weakness is the fact that the penalties for
allowing disasters to happen are generally financial as opposed, say, to an individual going to
jail. At Chevron I worked in countries where the result of mistakes could be prison. That really
makes you sit up and pay attention! Immediately I thought, how do I prevent someone I’ve

What I think we can conclude about Macondo is that the event itself was caused by very basic
mistakes in well control but the consequence, and the size of the consequence, was a result of
deepwater conditions. Blowouts have always been a concern but this level of consequence has
got to be completely unacceptable in our industry and cannot just be dismissed as “bad luck”.

People versus process

The public reaction to Macondo was standard: blame the individuals, and write new processes
(along with hiring new frontline people to enforce them). But I believe the response needs to be
deeper than finding a scapegoat and finding a process gap. The lesson I take from this is that
there are three necessary parts to building a process safety culture. One is leadership, one is the
actual process or standards, and then there is the culture itself, how we work. Those three
things should work together dynamically and reinforce each other.

The problem is, it’s infinitely easier, especially for engineers and technical people, to write a new
process. But we have enough processes, and it is pretty rare these days to find a truly

writing a new one we have to ask the tough questions. Why was it not being used? Does the
leadership know it well enough to talk about it with the frontline, to reinforce it?

Culture, behaviour, how we talk to each other, and about what – for engineers that’s all pretty
fuzzy, so the reflex is to create more process, more regulation, more audits, and beefed-up
equipment.

highly evolved and embedded. The question is always: did the mechanic, the pilot, the crew
follow the process? That’s where we have to move to. I’m very skeptical about new layers of
procedure being added when basic well control procedures, if followed, would work very
adequately to prevent another Macondo.

Do we have a culture problem?

North American culture wants less process, less legislation. There is an adversarial mindset
among industry players and between industry and the regulator. The values can be expressed
by statements like ‘less is adequate’, and ‘experience is a better guide than a highly codified
process’. There is a strong independent streak, as well. The concept of communal responsibility
that you see in parts of Europe, for instance, is foreign.

I think this has consequences. It is no surprise to me that onshore personal safety performance
in North America is among the worst in the world. I think the prevalent culture in oil and gas in
North America does present challenges but, having said that, all cultures do. I’ve worked in 15

norms and values and try to hitch those to your engine of change.

The strongest influences on culture are the regulatory environment, company leadership, and
peers. In the North American context a salient weakness is the fact that the penalties for
allowing disasters to happen are generally financial as opposed, say, to an individual going to
jail. At Chevron I worked in countries where the result of mistakes could be prison. That really
makes you sit up and pay attention! Immediately I thought, how do I prevent someone I’ve

Figure 1: Overview and classification of inspection solutions depending on the inspection environment. Further
discussion will be about the inspection methods encircled in red.

If an inspection technology can be redesigned to work on an ILI-tool this inspection task will
then become standard ILI operation. This process happens all the time. Here we shall focus on
cases where the inspection technique is not “pig-mountable”, or the technology does not work
from the inside. This remains the realm of external inspection, in most cases an external scan-
ning technique, but possibly also an external monitoring.

In particular for external inspection the deployment of the inspection device is a major aspect
of the inspection operation. In the o�shore industry, di�erent parts of structures demand
di�erent levels of inspection. The deployment method will very much depend on the exact
location of the inspected pipe section. An overview of di�erent deployment methods is given in
Figure 2. The two main methods are deployment from top-side or deployment subsea from an
ROV or a diver. Recent technical developments aim at avoiding diver operated inspections. If
deployed from top-side often rope access technicians will be required to position or clamp a
device to the pipe to be inspected. For subsea deployment a work class ROV will position the
device on a spot on the pipe, where it will start to move remotely controlled.

Obviously the structures inspected in this manner are not only pipelines, but any tubular com-
ponents. With such an extension of the inspection scope the issue of inspectable material and
material compositions is even more pronounced. The fact that a certain tubular structure is not
a pressure vessel does not make a di�erence for the external inspection.

Page 4

second-in-command briefed that person comprehensively on how they did things. You think
much more deeply about losing your personal freedom than you do about your company
paying a fine on your behalf.

As for leadership in North America, there are several problems. What’s emphasised most, overtly
or tacitly, is production and cost reduction. That combines with the rugged individualism
prevalent in the American psyche. Pressed to follow a new procedure that claims to be more

gas industry historically has reinforced this.

On the subject of disasters, it is very common for drilling managers to say ‘this won’t happen’. I
have sympathy with this. What they really mean is, it’s highly improbable. And they’re right: it is

one-in-hundred-thousand chance of something the scale of Macondo happening?
One-in-a-million? What does that even mean? This creates a kind of vacuum in terms of what
to focus on so it’s easier to say, either out loud or in your private thoughts, ‘this won’t happen’.
The way to avoid this trap is to say, yes, it will happen. It will happen to somebody, somewhere,
at some point in time. That’s all but guaranteed. Now, what are we going to do to make sure it
doesn’t happen to us? It’s a subtle but profound shift in thinking.

High reliability

If you fly domestically in the US, it will strike you just how unnervingly young some of the pilots
and co-pilots seem. But the training they receive is comprehensive, the safety culture they
operate in is pervasive, and the expectations on them to conform to it are rigorous and uniform.
This is the approach pioneered by so-called “high-reliability organisations” in the airline, nuclear
power and other industries, where mistakes just cannot happen. The likelihood of disaster on a
plane is very high if you do the wrong things, while on an oil well you can generally get it back
under control unless you do some really fundamental things wrong.

How does our industry compare to the airline industry? We’ve done a lot of work over the past
20 years on personnel safety. It’s now statistically safer to work on a drilling rig than on a farm
or a construction site. But if you factor in well control as a measure, and you create a safety
scale of one to four, I’d put the airline industry at four and oil and gas at around one or two.

consistency, the culture and the expectations.

For example, there are some generally accepted procedures for well control, and there is an

and understanding. If you compare the responsibilities of a pilot landing an airplane to those of

well-control incident, suddenly the driller needs the same level of proficiency and training and
process back-up that a pilot needs.

Various things set high-reliability organisations apart. They don’t ever allow a single person to be
the sole agent in a set of actions that could lead to system failure. They also have global
standards – there are certain ways planes are flown whatever country the pilot’s from.

second-in-command briefed that person comprehensively on how they did things. You think
much more deeply about losing your personal freedom than you do about your company
paying a fine on your behalf.

As for leadership in North America, there are several problems. What’s emphasised most, overtly
or tacitly, is production and cost reduction. That combines with the rugged individualism
prevalent in the American psyche. Pressed to follow a new procedure that claims to be more

gas industry historically has reinforced this.

On the subject of disasters, it is very common for drilling managers to say ‘this won’t happen’. I
have sympathy with this. What they really mean is, it’s highly improbable. And they’re right: it is

one-in-hundred-thousand chance of something the scale of Macondo happening?
One-in-a-million? What does that even mean? This creates a kind of vacuum in terms of what
to focus on so it’s easier to say, either out loud or in your private thoughts, ‘this won’t happen’.
The way to avoid this trap is to say, yes, it will happen. It will happen to somebody, somewhere,
at some point in time. That’s all but guaranteed. Now, what are we going to do to make sure it
doesn’t happen to us? It’s a subtle but profound shift in thinking.

High reliability

If you fly domestically in the US, it will strike you just how unnervingly young some of the pilots
and co-pilots seem. But the training they receive is comprehensive, the safety culture they
operate in is pervasive, and the expectations on them to conform to it are rigorous and uniform.
This is the approach pioneered by so-called “high-reliability organisations” in the airline, nuclear
power and other industries, where mistakes just cannot happen. The likelihood of disaster on a
plane is very high if you do the wrong things, while on an oil well you can generally get it back
under control unless you do some really fundamental things wrong.

How does our industry compare to the airline industry? We’ve done a lot of work over the past
20 years on personnel safety. It’s now statistically safer to work on a drilling rig than on a farm
or a construction site. But if you factor in well control as a measure, and you create a safety
scale of one to four, I’d put the airline industry at four and oil and gas at around one or two.

consistency, the culture and the expectations.

For example, there are some generally accepted procedures for well control, and there is an

and understanding. If you compare the responsibilities of a pilot landing an airplane to those of

well-control incident, suddenly the driller needs the same level of proficiency and training and
process back-up that a pilot needs.

Various things set high-reliability organisations apart. They don’t ever allow a single person to be
the sole agent in a set of actions that could lead to system failure. They also have global
standards – there are certain ways planes are flown whatever country the pilot’s from.

Figure 2: Di�erent methods for deployment depicted

To illustrate the inspection technique, as well as the deployment challenges a few case studies
shall be presented. At Innospection SLOFEC in combination with UT spot checks has been
found to be an adaptable testing technology for the various tasks described above. The SLOFEC
technology has been described before [1]. In essence it consists of an eddy current technology
under simultaneous magnetization of the pipe to be inspected. This allows for the inspection of
wall thickness reductions and can be used not only for bare carbon steel pipe, but also for a
combination of metals and polymers. The polymer itself, which can be a coating or another
structural part of the pipe, is not inspected, but also does not impede the inspection of the
metallic parts.

Case Studies

Internal Leg Inspection
The task had been to inspect the inside of a platform leg for corrosion type defects. Access was
only possible through a hole of a size of 15x35 cm. In addition there was an internal cone
blocking straight access at the location of the hole. An internal inspection from the top was not
possible due to various internal objects. The inspection was required from the elevation of the
hole downwards into the water level. An inspection coverage as high as possible was desired.
The access to the leg is shown in Figure 3.

Page 5

The road to there

DuPont uses a term, “felt leadership”, to describe its philosophy of process safety management.
It means that frontline people at DuPont should feel the sincerity, the consistency, and the
commitment of management to safety. How? By the managers being visible in the field, talking
about the issues, demonstrating by their engagement that they really care. Their task is
constantly to keep the culture alive, and to challenge, to pause and ask questions. Are you sure
about this? What’s changed, what’s new? They support peer-to-peer challenging, too. It’s a
daily, evolving conversation.

The man who recruited me to Chevron many years ago, Carnie Block, “got” this even before
there was a fancy term for it. When he went to the field, he tried never to have more than one
conversation. If he was there to talk about safety, that’s all he talked about. If it was business, it
was business. He didn’t want to dilute the purpose of his visit. That made a big impression: it
registered with me how we send mixed signals. For Carnie it wasn’t just ‘the company line’, it
was a true internal value and it didn’t change even if they were behind forecast.

Process deficiency is rarely the fault of the process. Very few people intentionally make mistakes
but they may not follow a process, or they may not know about it, or, over time, process
corner-cutting is reinforced when nothing bad happens right away. This is how process
deficiency propagates. It’s almost inevitable, but what combats this is a culture in which
somebody else can speak up and say, hang on, that’s not what we do, and where the leadership
is constantly asking questions, probing, making sure people are not getting complacent. Only
such a living, holistic system of checks and balances will keep small errors from escalating into
major incidents.

• Speaking at DecomWorld’s in Houston, 29
September-1 October, in Houston, Kevin Lacy recently retired from Talisman Energy as Senior
Vice President of Drilling and Completions. After spending 26 years with Chevron, Kevin joined
BP in July 2006, where he became VP for Drilling and Completions in the Gulf of Mexico

The road to there

DuPont uses a term, “felt leadership”, to describe its philosophy of process safety management.
It means that frontline people at DuPont should feel the sincerity, the consistency, and the
commitment of management to safety. How? By the managers being visible in the field, talking
about the issues, demonstrating by their engagement that they really care. Their task is
constantly to keep the culture alive, and to challenge, to pause and ask questions. Are you sure
about this? What’s changed, what’s new? They support peer-to-peer challenging, too. It’s a
daily, evolving conversation.

The man who recruited me to Chevron many years ago, Carnie Block, “got” this even before
there was a fancy term for it. When he went to the field, he tried never to have more than one
conversation. If he was there to talk about safety, that’s all he talked about. If it was business, it
was business. He didn’t want to dilute the purpose of his visit. That made a big impression: it
registered with me how we send mixed signals. For Carnie it wasn’t just ‘the company line’, it
was a true internal value and it didn’t change even if they were behind forecast.

Process deficiency is rarely the fault of the process. Very few people intentionally make mistakes
but they may not follow a process, or they may not know about it, or, over time, process
corner-cutting is reinforced when nothing bad happens right away. This is how process
deficiency propagates. It’s almost inevitable, but what combats this is a culture in which
somebody else can speak up and say, hang on, that’s not what we do, and where the leadership
is constantly asking questions, probing, making sure people are not getting complacent. Only
such a living, holistic system of checks and balances will keep small errors from escalating into
major incidents.

• Speaking at DecomWorld’s in Houston, 29
September-1 October, in Houston, Kevin Lacy recently retired from Talisman Energy as Senior
Vice President of Drilling and Completions. After spending 26 years with Chevron, Kevin joined
BP in July 2006, where he became VP for Drilling and Completions in the Gulf of Mexico

Figure 3: The access for a keyhole inspection of a leg

The devised inspection tool was required to be su�ciently narrow. It is shown in the right part
of Figure 4.
In its final configuration is consisted of a SLOFEC unit for corrosion testing, a camera for visual
inspection and a PEC unit for quantitative wall thickness testing. PEC stands for Pulsed Eddy
Current and is also widely used in the testing of o�shore structures [2].

Figure 4: Left: The arm to mount the scanner on the hole. The scanner (right) could be lowered
into the leg by the means of a steel rope. The pulley was inside the leg.

The left of Figure 4 shows the device that allowed for mounting the scanner internally near the
hole and also allowed for swiveling the scanner around the internal surface.

Riser with external Monel cladding
The task in this case consisted of the inspection of a riser which was externally clad with a
Monel alloy. Monel is an alloy with high Nickel content. Nevertheless it is not magnetic, but
electrically conductive. It shows excellent resistance against corrosion.

Page 6

The riser had to be inspected for external corrosion, i.e. metal loss in the interface between
Monel and steel. The particular interest was in the splash zone. The device had to be attached
below a riser clamp, which is shown in the right of Figure 5. ILI in risers is usually possible, if the
corresponding pipeline is piggable. However, the data often shows poor quality, as the speed is
uncontrolled.

Figure 5: Left: The inspection device for a mock-up testing. The red encircled spot shows a SLOFEC device scanning
in the circumference. The right shows the device being deployed from top-side and performing its inspection in the
splash zone.

The left of Figure 5 shows the device being tested. The scanner itself is shown in the red circle.
The cladding had overlapping parts with the overlap welded in the circumferential direction.
The scanning had to be in the circumference, because signals originating from the weld would
have masked defects underneath. Scanning in the axial direction of the riser would have been a
much easier task. The device consists of a lower rotating part and an upper stationary part. Both
parts can be opened to allow for clamping onto the riser.

The SLOFEC technique can be adapted to measure through layers of conductive material, if the
material is not magnetic. In addition cameras observe the scanned area. Workshop verification
tests have shown, that metal loss in the carbon steel riser can indeed be observed in this
manner. In the particular project it was possible to show the absence of defects.

The technology also demonstrates the principal ability to inspect internal CRA lined or cladded
pipe.

Inspection of flexible riser
The issue of inspecting flexible risers is complex and has been discussed before [1]. They are a
good example of uninspectable pipeline, as pigs have been passing through flexible riser often.
The inspection of flexible risers is of utmost importance. A considerable number of flexible
risers are known to have damage in the outer sheath. This will lead to degradation and reduces
the calculated lifetime. The degradation mechanisms usually consist of water ingress, flooded
annulus, and corrosion in the armored

Page 7

wires and reduced fatigue life time. The deployment method is also of major interest. In the
project shown here the riser had to be inspected near the splash zone, but to water depth at
least to -20m. The scanning is done in the axial direction. Since the scanning needs to cover
the full circumference and the orientation of the device on the riser needs to be defined, the
device can also rotate on the riser. The left of Figure 6 shows Innospection’s MEC-HUG™ tool
that uses hydraulic power to run axially and circumferentially on the riser pipe.

The MEC-HUG™ tool is equipped with buoyancy block on top visible in Figure 6. Once the tool
is submersed, it floats and freely moves in water by the hydraulic motors. The steel rope
remains attached for safety reasons but is no longer required to steer the tool. Encoder wheels
on the tool allow for positioning the device. The right in Figure 6 shows an excerpt of the
inspection report. The typical helical structure of flexible riser pipe is visible. The full circumfer-
ence is scanned with di�erent tracks. They are later concatenated to yield the full picture. With
a given datum point any position on the riser can be reached and reinspected.

Figure 6: Left: The MEC-HUG™ tool being attached to the riser. It runs in axial an circumferential orientation. The
inspection is performed while running axially. The data is shown on the right.

Unpiggable Subsea Pipeline
In this project the task was to inspect an unpiggable subsea pipeline. It was deemed possible
that the pipeline su�ered from top-of-the-line corrosion. Hence the focus was on the top
position for inspection. The coating consisted of a 3-layer Polyethylene with a thickness of a
few mm. Sections of several meters were to be inspected. A rough cleaning had to be
performed prior to inspection. The inspection tool is a modified MEC™-CombiCrawler. It is
seen lying in front of a Work class ROV in the left of Figure 7. Again it is equipped with buoyancy
to ensure no resulting torque is exerted on the tool when running on the pipeline. This allowed
to tool to also run stable in the 11 and 1 o’clock position.

Similer Documents