API 570 5 Inspection, Examination, and
Pressure Testing Practices
5.1 - ANSInspection Plans
5.1.1 Piping Systemization and Circuitization - ANSIn order to develop inspection plans
(including scope, frequency, techniques and location), facility piping should be broken down
into piping systems and circuits. Piping systems can be defined at a PFD (process flow
diagram) level however piping circuits are often defined at the P&ID (process and
instrumentation diagram) level. Potential damage mechanisms are primarily a function of the
process/operating conditions, the material of construction and mechanical design. Defining
systems and circuits based upon potential damage mechanisms can yield an inspection plan
with a high probability of defecting damage. The Piping systemization is the first cut for
defining the potential corrosion issues and is a convenient reference to the general location
of damage mechanisms within the process unit. Piping systems generally have common
characteristics such as one or more of the following:
a) process intent (e.g. overhead reflux system);
b) process control scheme (e.g. temperature/end point);
c) process stream composition;
d) design operating conditions;
e) similar or related set of IOWs.
Piping systems may contain (or pass through) one or more equipment items (e.g.
exchangers, pumps) and will typically contain one or multiple piping circuits. Piping systems
and circuits developed from expected/identified damage mechanisms enables development
of concise inspection plans and forms the basis for improved data analysis. Piping
circuitization is a further breakdown of piping systems into sections of piping and/or
individual pipe components which have common damage mechanisms, same material of
construction and have similar damage rates and modes.
Refer to API 574 for more information on development of piping systems and circuits.
5.1.2 Development of an Inspection Plan - ANSAn inspection plan shall be established for all
piping systems and/or circuits and associated pressure relieving devices within the scope of
this Code. The inspection plan shall be developed by the inspector and/or engineer. A
corrosion specialist shall be consulted to identify/clarify potential damage mechanisms and
specific locations where degradation my occur, especially where localized corrosion or
cracking mechanisms may be involved. A corrosion specialist shall be consulted when
developing the inspection plans for piping systems that operate at elevated temperatures
[above 750 °F (400 °C)] and piping systems that operate below the ductile-to-brittle transition
temperature. Special attention in the inspection plan should be given to any types of
deterioration or issues listed in 5.5.2.
,The inspection plan is developed from the analysis of several sources of data including the
piping inspection records. Piping systems shall be evaluated based on present or possible
types of damage mechanisms. The methods and that extent of NDE shall be evaluated to
assure that they can adequately identify the damage mechanism and the severity of
damage. Subdividing piping systems into circuits subject to common damage mechanisms
facilitates selecting the inspection techniques best suited to find the damage that's most
likely to occur in the piping circuit. Examinations shall be scheduled at intervals that consider
the:
a) type of damage (see API 571);
b) rate of damage progression;
c) tolerance of the equipment to the type of damage;
d) capability of the NDE method to identify the damage;
e) maximum intervals as defined in codes and standards;
f) extent of examination;
g) recent operating history, including IOW exceedances;
h) MOC records that my impact inspection plans;
i) RBI assessments or piping classification.
The inspection
5.1.3 Minimum Contents of an Inspection Plan - ANSThe inspection plan shall contain the
inspection tasks and schedule require to monitor identified damage mechanisms and assure
the pressure integrity of the piping systems. The plan should:
a) define the type(s) of inspection needed, (e.g. internal, external, on-stream, nonintrusive);
b) identify the next inspection date for inspection type;
c) describe the inspection methods and NDE techniques;
d) describe the extent and locations of inspection and NDE at CMLs;
e) describe the surface cleaning requirements needed for inspection and examinations for
each type of inspection;
f) describe the requirements of any needed pressure test (e.g. type of test, test pressure,
test temperature, and duration);
g) describe any required repairs if known or previously planned before the upcoming
inspection;
h) describe the types of damage anticipated or experienced in the piping systems;
i) define the location of the expected damage;
j) define any special access and preparation needed.
Generic inspection plans based on industry standards and practices may be used as a
starting point in developing specific inspection plans. The inspection plan may or may not
exist in a single document, however the contents of the plan should be readily accessible
from inspection data systems.
5.2 - ANSRBI Risk-based inspection
5.2.1 General - ANSAn RBI analysis may be used to determine inspection intervals or due
dates and the type and extent of future inspection/examinations. The RBI analysis, when
conducted in accordance with API 580, shall include all of the inspection planning elements
noted in API 580, Section 5.2
, When the owner/user chooses to conduct an RBI assessment it shall include a systematic
evaluation of both the probability and the associated consequences of failure, in accordance
with the requirements in API 580. API 581 provides a set of methodologies for assessing risk
(both POF and COF) and for developing inspection plans that are consistent with key
elements defined in API 580.
Identifying and evaluating potential damage mechanisms, current equipment condition and
the effectiveness of the past inspection are important steps in assessing the probability of
piping failure. Identifying and evaluating the process fluid(s), potential injuries, environmental
damage, equipment damage and equipment downtime are important steps in assessing the
consequence of piping failure. Identifying integrity operating windows for key process
variables is an important adjunct to RBI (see 4.3.1.4).
5.2.2 Probability Assessment - ANSThe probability assessment shall be in accordance with
the requirements in API 580 and shall be based on all forms of damage that could
reasonably be expected to affect equipment in any particular service. Additionally, the
effectiveness of the inspection practices, tools, and techniques used for finding the potential
damage mechanisms shall be evaluated.
Other factors that should be considered in a probability assessment include:
a) appropriateness of the materials of construction for the damage mechanisms;
b) equipment design conditions, relative to operating conditions;
c) appropriateness of the design codes and standards utilized;
d) effectiveness of corrosion monitoring programs;
e) the quality of maintenance and inspection quality assurance/quality control programs.
f) both the pressure retaining and structural requirements;
g) operating conditions both past and projected and review of potential fouling as it impacts
damage mechanisms;
h) prior mechanical/corrosion or failure history of the piping system/circuit;
i) review of inspection history.
5.2.3 Consequence Assessment - ANSThe consequence of a release is dependent on type
and amount of process fluid contained in the equipment. The consequence assessment shall
be in accordance with the requirements in API 580 and shall consider the potential incidents
that may occur as a result of fluid release, the size of a potential release, and the type of a
potential release (includes explosion, fire, or toxic exposure). The assessment should also
determine the potential outcomes that may occur as a result of fluid release or equipment
damage, which may include: health effects, environmental impact, additional equipment
damage, and process downtime or slowdown.
5.2.4 Documentation - ANSIt is essential that all RBI assessments be thoroughly
documented in accordance with the requirements in API 580 clearly defining all the factors
contributing to both the probability and consequences of a failure of the equipment.
After RBI assessment is conducted, the results can be used to establish the equipment
inspection plan and better define the following:
a) the most appropriate inspection and NDE methods, tools and techniques;
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Qualityexam. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $10.49. You're not tied to anything after your purchase.
