Hydrocarbon Processing - June 2022 - GP-10
SPECIAL FOCUS: PIPELINES & TRANSPORT
with demonstrated understanding
and experience in the application of
engineering and risk management
principles related to the issues being
assessed.1
assessments specific to the circumstance at
hand, and they will generally be referred to
as engineering assessments in this article.
The circumstances for, and the use of,
In the Canadian standard,
an engineering assessment applies
to demonstrating fitness-for-service
in a variety of circumstances.
* Engineering critical assessment:
An analytical procedure, based on
fracture mechanics principles, that
allows determination of the maximum
tolerable sizes for imperfections
in fusion welds.1
In the Canadian
standard, an engineering critical
assessment applies specifically to
the consideration of imperfections
in girth welds after construction.
Guidance on the application of
engineering critical assessments to
girth welds is provided in Annex J
of the standard.
The U.S. codes do not specifically define
the term engineering assessment; however,
engineering critical assessment is defined
in 49 CFR Part 192.3 (referenced in
Subpart L, sections 192.624 and 192.632)3
as part of the Gas Mega Rule and new
MAOP reconfirmation requirements:
* Engineering critical assessment:
A documented analytical procedure
based on fracture mechanics
principles, relevant material
properties (mechanical and fracture
resistance properties), operating
history, operational environment,
in-service degradation, possible failure
mechanisms, initial and final defect
sizes, and usage of future operating
and maintenance procedures to
determine the maximum tolerable
sizes for imperfections based upon the
pipeline segment maximum allowable
operating pressure.3
In the U.S. code,
an engineering critical assessment
is not specific to flaws in girth welds
and has a broader fitness-for-service
intent across various threat and
defect types that overlaps with that
of engineering assessments in the
Canadian standard.
In summary, whether we are talking
about the CSA's engineering assessment
or the U.S. CFR engineering critical assessment,
these are both detailed fitness-forservice
assessments that can consider various
threats and defect types. This article
focuses on these types of assessments, in
the context of thorough fitness-for-service
10 MAY/JUNE 2022 | GasProcessingNews.com
engineering assessments (Canada) and
engineering critical assessments (U.S.) are
converging in Canada and the U.S., including,
but not limited to, the following:
* Class location designation changes
* Licensed MOP for Canada,
approved MAOP for U.S. or
MAOP upgrades
* Defect assessments or evaluations
of damage
* Flow reversal or change in service
* Reactivating or repurposing
a pipeline
* Pressure testing an existing pipeline
* Valve location and spacing
* MAOP validation and
reconfirmation (U.S.)
* Special permits (U.S.)
* Governance (safety and reliability
case management)
* Return to service after failure
or outage.
Class location designation changes are
expected to continue to be a key driver for
engineering assessments and engineering
critical assessments in both Canada
and the U.S., respectively. The industry is
spending hundreds of millions of dollars
every year on pipe replacements where
the existing pipe does not align with design
requirements for the new class location
designation.
CSA Z662 Clause 10.7.2 requires a
conformance check of five key elements
(mainly design related) for pipe in a class
location designation change area. This
includes the design factor or location factor,
valve spacing, depth of cover, pressure
testing and evaluation, and repair of
imperfections. While provisions exist for
engineering assessments to be carried out
if one or more of the five elements cannot
be met, it is acknowledged that deviations
from design-based elements can create a
challenge for gaining stakeholder approval
and can result in replacement or pressure
reduction actions that are not necessarily
performance based or that can measurably
improve pipeline reliability and safety.
Similarly, in the U.S., current approaches
to evaluate a pipeline's fitness-for-service
in class location designation change
circumstances are very arduous via the
special permitting process [or potentially,
in the future, through the current Notice
of Proposed Rulemaking (NPRM) related
to class location change requirements].
Reconfirmation of MAOP has the potential
for creating billions of dollars of
effort/impact if the industry must rely on
replacements, pressure reductions and
pressure tests for compliance. Engineering
assessment methodology or other technology
solutions can provide an alternative
pathway forward when there is sound technical
evidence that the pipe is otherwise
fit-for-service. There are some cases where
pipe replacement is required, but the engineering
assessment should support this.
Driving factors and trends. There is a
universal mandate from corporate governance
structures, new and emerging
regulations, and the public to increase
pipeline safety and reliability performance.
The success of these efforts is
critical to maintain the industry's social
license to operate. It is important to note
that the industry has made great strides in
improving pipeline safety and reliability
performance through compliance with
integrity management, operational and
maintenance regulations, and the application
of initiatives to move beyond compliance
only. Although the industry, regulatory
community and public have been
diligently working to determine how best
to increase pipeline safety performance,
all stakeholders acknowledge that the
next level of performance will not be easy
to accomplish from technical, operational
and commercial perspectives.
Without the insight and analyses from
engineering assessments in application
with improved technology for enhanced
data gathering/integration and assessment,
compliance may result in pipe replacements,
pressure reductions, pressure
testing and other material actions on pipe
that is otherwise fit-for-service. These
massive resource allocations can be otherwise
directed more effectively toward mitigating
priority safety and reliability risks.
The U.S.
regulatory structure continues
to go through significant changes
that will facilitate gaining the next level
of pipeline safety and reliability performance.
Part 1 of the Gas Mega Rule contains
changes to the regulations for gas
transmission pipelines, along with new
requirements for the verification of pipeline
materials. This part of the rule aims
to improve safety with the transportation
and operation of onshore gas transmis
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Hydrocarbon Processing - June 2022
Table of Contents for the Digital Edition of Hydrocarbon Processing - June 2022
Contents
Hydrocarbon Processing - June 2022 - Cover1
Hydrocarbon Processing - June 2022 - Cover2
Hydrocarbon Processing - June 2022 - Contents
Hydrocarbon Processing - June 2022 - 4
Hydrocarbon Processing - June 2022 - 5
Hydrocarbon Processing - June 2022 - 6
Hydrocarbon Processing - June 2022 - 7
Hydrocarbon Processing - June 2022 - 8
Hydrocarbon Processing - June 2022 - 9
Hydrocarbon Processing - June 2022 - 10
Hydrocarbon Processing - June 2022 - 11
Hydrocarbon Processing - June 2022 - 11A
Hydrocarbon Processing - June 2022 - 11B
Hydrocarbon Processing - June 2022 - 12
Hydrocarbon Processing - June 2022 - 13
Hydrocarbon Processing - June 2022 - 14
Hydrocarbon Processing - June 2022 - 15
Hydrocarbon Processing - June 2022 - 16
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Hydrocarbon Processing - June 2022 - 33
Hydrocarbon Processing - June 2022 - 34
Hydrocarbon Processing - June 2022 - 35
Hydrocarbon Processing - June 2022 - 36
Hydrocarbon Processing - June 2022 - 37
Hydrocarbon Processing - June 2022 - 38
Hydrocarbon Processing - June 2022 - 39
Hydrocarbon Processing - June 2022 - 40
Hydrocarbon Processing - June 2022 - 41
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Hydrocarbon Processing - June 2022 - 50
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Hydrocarbon Processing - June 2022 - 60
Hydrocarbon Processing - June 2022 - 61
Hydrocarbon Processing - June 2022 - 62
Hydrocarbon Processing - June 2022 - 63
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Hydrocarbon Processing - June 2022 - 65
Hydrocarbon Processing - June 2022 - 66
Hydrocarbon Processing - June 2022 - 67
Hydrocarbon Processing - June 2022 - 68
Hydrocarbon Processing - June 2022 - 69
Hydrocarbon Processing - June 2022 - 70
Hydrocarbon Processing - June 2022 - 71
Hydrocarbon Processing - June 2022 - 72
Hydrocarbon Processing - June 2022 - 73
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Hydrocarbon Processing - June 2022 - 86
Hydrocarbon Processing - June 2022 - 87
Hydrocarbon Processing - June 2022 - 88
Hydrocarbon Processing - June 2022 - 89
Hydrocarbon Processing - June 2022 - 90
Hydrocarbon Processing - June 2022 - Cover3
Hydrocarbon Processing - June 2022 - Cover4
Hydrocarbon Processing - June 2022 - GP-1
Hydrocarbon Processing - June 2022 - GP-2
Hydrocarbon Processing - June 2022 - GP-3
Hydrocarbon Processing - June 2022 - GP-4
Hydrocarbon Processing - June 2022 - GP-5
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Hydrocarbon Processing - June 2022 - GP-11
Hydrocarbon Processing - June 2022 - GP-12
Hydrocarbon Processing - June 2022 - GP-13
Hydrocarbon Processing - June 2022 - GP-14
Hydrocarbon Processing - June 2022 - GP-15
Hydrocarbon Processing - June 2022 - GP-16
Hydrocarbon Processing - June 2022 - GP-17
Hydrocarbon Processing - June 2022 - GP-18
Hydrocarbon Processing - June 2022 - GP-19
Hydrocarbon Processing - June 2022 - GP-20
Hydrocarbon Processing - June 2022 - GP-21
Hydrocarbon Processing - June 2022 - GP-22
Hydrocarbon Processing - June 2022 - GP-23
Hydrocarbon Processing - June 2022 - GP-24
Hydrocarbon Processing - June 2022 - GP-25
Hydrocarbon Processing - June 2022 - GP-26
Hydrocarbon Processing - June 2022 - GP-27
Hydrocarbon Processing - June 2022 - GP-28
Hydrocarbon Processing - June 2022 - GP-29
Hydrocarbon Processing - June 2022 - GP-30
Hydrocarbon Processing - June 2022 - GP-31
Hydrocarbon Processing - June 2022 - GP-32
Hydrocarbon Processing - June 2022 - GP-33
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Hydrocarbon Processing - June 2022 - GP-35
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Hydrocarbon Processing - June 2022 - GP-44
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_200910
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200909
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200908
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200907
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200906
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200905
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200904
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200903
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200902
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200901
https://www.nxtbookmedia.com