API RP 571 EXAM STUDY GUIDE
1 Scope - Answer -This recommended practice discusses damage mechanisms
applicable to oil refineries; however, much of the information herein can also be applied
to petrochemical and other industrial applications, as the user deems appropriate. It is
up to the user determine the applicability and appropriateness of the information
contained herein as it applies to their facility.
API 571 is a reference document that provides useful information by itself and also
complements other API standards and recommended practices. The document should
be utilized as a reference to other integrity related documents. It is intended to
contribute to the overall management of pressure equipment integrity and is a useful
resource for many mechanical integrity program activities including:
a) identification of existing damage or deterioration and anticipated rates of degradation,
b) identification of future damage mechanism susceptibilities,
c) development and maintenance of inspection and monitoring strategies, programs,
and plans (e.g. per API 510, API 570, and API 653),
d) implementation and monitoring of integrity operating windows (IOWS) (see API 584),
e) development of corrosion control documents (CCDs) (See API 970),
f) implementation of Risk-Based Inspection (RBI) programs (see API 580 and API 581),
g) conducting Fitness-For-Service (FFS) assessments (see API 579-1/ASME FFS-1).
h) application of proper examination techniques, and
i) conducting pressure equipment integrity incident investigations (see API 585).
The information for each damage mechanism provided in a set format as shown below.
--- Name of the Mechanism--- The term commonly used to describe or name the
mechanism
--- Description of Damage--- A basic description of the damage mechanism.
--- Affected Materials--- A list of the materials prone to the damage mechanism.
--- Critical Fa
2 - Answer -Terms and Definitions
2.1 Definitions - Answer -For the purposes of this document, the following definitions
apply.
2.1.1 austenitic - Answer -A term that refers to a type of metallurgical structure
(austenitic) normally found in 300 series stainless steel (SS) and nickel-based alloys.
These materials have a face centered cubic crystallographic structure and are generally
nonmagnetic.
2.1.2 austenitic stainless steels - Answer -The 300 series SS, which commonly include
Types 304, 304L, 304H, 309, 310, 316, 316L, 317, 317L, 321, 321H, 347, and 347H.
, The "L" and "H" suffixes refer to controlled ranges of low and high carbon content,
respectively. These alloys are characterized by an austenitic structure.
2.1.3 carbon steel - Answer -An alloy consisting primarily of iron (Fe) with a small
amount of carbon (C). Carbon steels do not have alloying elements intentionally added.
However, there may be small amounts of elements permitted by specifications such as
ASTM A516 and ASTM A106, for example, that can affect corrosion-related properties,
hardiness after welding, and toughness. Elements that may be found in small quantities
include Mn, Cr, Ni, Mo, Cu, S, Si, P, Al, V, and B.
2.1.4 diethanolamine (DEA) - Answer -Chemical used in amine treating to remove H2S
and CO2 from hydrocarbon streams.
2.1.5 diglycolamine (DGA) - Answer -Chemical used in amine treating to remove H2S
and CO2 from hydrocarbon streams.
2.1.6 duplex stainless steel - Answer -A family of stainless steels that contain a mixed
austenitic-ferritic structure including Alloys 2205, 2304, and 2507. The welds of 300
series SS may also exhibit a duplex structure.
2.1.7 ferritic - Answer -A term that refers to a type of metallurgic structure (ferrite)
normally found in carbon and low-ally steels and many 400 series SS. These materials
have a body centered cubic crystallographic structure and are generally magnetic.
2.1.8 ferritic stainless steels - Answer -A family of stainless steels including Types 405,
409, 410S, 430, 442, and 446.
2.1.9 heat-affected zone (HAZ) - Answer -The portion of the base metal adjacent to a
weld that has not been melted, but in which the metallurgical microstructure and
mechanical properties have been changed by the heat of welding, sometimes with
undesirable effects.
2.1.10 high-strength low-alloy steel (HSLA steel) - Answer -A family of carbon steels in
which higher strength levels are achieved by the addition of moderate amounts of
alloying elements such as titanium, vanadium, or nioblum in amounts of less than 0.1%.
They can be more sensitive to cracking during fabrication from hydrogen embrittlement
(HE) (delayed cracking; also known as underbead cracking).
2.1.11 low-alloy steel - Answer -A family of steels containing up to 9% chromium and
other alloying additions for high temperature strength and creep resistance. The low-
alloy steels commonly encountered in refining include C-0.5Mo, Mn-0.5Mo, 1Cr-0.5Mo,
1.25Cr-0.5Mo, 2.25Cr-1.oMo, 5Cr-0.5Mo, and 9Cr-1Mo. These are considered ferritic
steels, although their microstructures might be an alteration of the ferrite phase found in
carbon steel.
1 Scope - Answer -This recommended practice discusses damage mechanisms
applicable to oil refineries; however, much of the information herein can also be applied
to petrochemical and other industrial applications, as the user deems appropriate. It is
up to the user determine the applicability and appropriateness of the information
contained herein as it applies to their facility.
API 571 is a reference document that provides useful information by itself and also
complements other API standards and recommended practices. The document should
be utilized as a reference to other integrity related documents. It is intended to
contribute to the overall management of pressure equipment integrity and is a useful
resource for many mechanical integrity program activities including:
a) identification of existing damage or deterioration and anticipated rates of degradation,
b) identification of future damage mechanism susceptibilities,
c) development and maintenance of inspection and monitoring strategies, programs,
and plans (e.g. per API 510, API 570, and API 653),
d) implementation and monitoring of integrity operating windows (IOWS) (see API 584),
e) development of corrosion control documents (CCDs) (See API 970),
f) implementation of Risk-Based Inspection (RBI) programs (see API 580 and API 581),
g) conducting Fitness-For-Service (FFS) assessments (see API 579-1/ASME FFS-1).
h) application of proper examination techniques, and
i) conducting pressure equipment integrity incident investigations (see API 585).
The information for each damage mechanism provided in a set format as shown below.
--- Name of the Mechanism--- The term commonly used to describe or name the
mechanism
--- Description of Damage--- A basic description of the damage mechanism.
--- Affected Materials--- A list of the materials prone to the damage mechanism.
--- Critical Fa
2 - Answer -Terms and Definitions
2.1 Definitions - Answer -For the purposes of this document, the following definitions
apply.
2.1.1 austenitic - Answer -A term that refers to a type of metallurgical structure
(austenitic) normally found in 300 series stainless steel (SS) and nickel-based alloys.
These materials have a face centered cubic crystallographic structure and are generally
nonmagnetic.
2.1.2 austenitic stainless steels - Answer -The 300 series SS, which commonly include
Types 304, 304L, 304H, 309, 310, 316, 316L, 317, 317L, 321, 321H, 347, and 347H.
, The "L" and "H" suffixes refer to controlled ranges of low and high carbon content,
respectively. These alloys are characterized by an austenitic structure.
2.1.3 carbon steel - Answer -An alloy consisting primarily of iron (Fe) with a small
amount of carbon (C). Carbon steels do not have alloying elements intentionally added.
However, there may be small amounts of elements permitted by specifications such as
ASTM A516 and ASTM A106, for example, that can affect corrosion-related properties,
hardiness after welding, and toughness. Elements that may be found in small quantities
include Mn, Cr, Ni, Mo, Cu, S, Si, P, Al, V, and B.
2.1.4 diethanolamine (DEA) - Answer -Chemical used in amine treating to remove H2S
and CO2 from hydrocarbon streams.
2.1.5 diglycolamine (DGA) - Answer -Chemical used in amine treating to remove H2S
and CO2 from hydrocarbon streams.
2.1.6 duplex stainless steel - Answer -A family of stainless steels that contain a mixed
austenitic-ferritic structure including Alloys 2205, 2304, and 2507. The welds of 300
series SS may also exhibit a duplex structure.
2.1.7 ferritic - Answer -A term that refers to a type of metallurgic structure (ferrite)
normally found in carbon and low-ally steels and many 400 series SS. These materials
have a body centered cubic crystallographic structure and are generally magnetic.
2.1.8 ferritic stainless steels - Answer -A family of stainless steels including Types 405,
409, 410S, 430, 442, and 446.
2.1.9 heat-affected zone (HAZ) - Answer -The portion of the base metal adjacent to a
weld that has not been melted, but in which the metallurgical microstructure and
mechanical properties have been changed by the heat of welding, sometimes with
undesirable effects.
2.1.10 high-strength low-alloy steel (HSLA steel) - Answer -A family of carbon steels in
which higher strength levels are achieved by the addition of moderate amounts of
alloying elements such as titanium, vanadium, or nioblum in amounts of less than 0.1%.
They can be more sensitive to cracking during fabrication from hydrogen embrittlement
(HE) (delayed cracking; also known as underbead cracking).
2.1.11 low-alloy steel - Answer -A family of steels containing up to 9% chromium and
other alloying additions for high temperature strength and creep resistance. The low-
alloy steels commonly encountered in refining include C-0.5Mo, Mn-0.5Mo, 1Cr-0.5Mo,
1.25Cr-0.5Mo, 2.25Cr-1.oMo, 5Cr-0.5Mo, and 9Cr-1Mo. These are considered ferritic
steels, although their microstructures might be an alteration of the ferrite phase found in
carbon steel.
