API 570 Q&A Flashcards
- API 570 covers inspection, repair, alteration, and rerating procedures for metallic piping systems that
have been in-service
API 570 was developed for the petroleum refining and chemical process industries.it may be used?
It may be used, where practical, for any piping system.
API 570 ________ be used as a substitute for the original construction requirements governing a piping
system before it is placed in-service.
shall not
API 570 applies to piping systems for process fluids, hydrocarbons, and similar flammable or toxic fluid
services. Which of the following services is not specifically applicable?
Water, steam condensate, boiler feed water
Some of the classes of piping systems that are excluded or optional for coverage under API 570 are listed
below. Which one is a mandatory included class?
Catalyst lines
The _________ shall be responsible to the owner-user for determining that the requirements of API 570 for
inspection, examination, and testing are met
Inspector
Who is responsible for the control of piping system inspection programs, inspection frequencies, and
maintenance of piping?
Owner-User.
An Authorized Piping Inspector shall have the following qualifications. Pick the one that does not belong in
this list
Four years of experience inspecting in-service piping systems
Risk Based Inspections include which of the following
Likelihood assessment.
b. Consequence analysis.
c. Operating and Inspection histories
An RBI assessment can be used to alter the inspection strategy provided
The degradation methods are identified.
b. The RBI is fully documented
Which one of the following is not a specific type or an area of deterioration?
Rectifier performance
Injection points subject to accelerated or localized corrosion may be treated as ________.
separate inspection circuits
The recommended upstream limit of inspection of an injection point is a minimum of:
12 inches or 3 pipe diameters whichever is greater
The recommended downstream limit of inspection of an injection point is a minimum of:
second change in flow direction past the injection point, or 25 feet beyond the first change in flow direction
whichever is less
Select thickness measurement locations (TMLs) within injection point circuits subject to localized corrosion
according to the following guidelines.
Establish TMLs on appropriate fittings within the injection point circuit,Establish TMLs on the pipe wall at the location of expected pipe wall impingement or injected fluid.
d. Establish TMLs at both the upstream and downstream limits of the injection point circuit.
What are the preferred methods of inspecting injection points?
Radiography and/or ultrasonics
During periodic scheduled inspections, more extensive inspection should be applied to an area beginning
__________ upstream of the injection nozzle and continuing for at least __________ pipe diameters
downstream of the injection point.
12 inches, 10
- Why should deadlegs in piping be inspected?
The corrosion rate in deadlegs can vary significantly from adjacent active piping.
Both the stagnant end and the connection to an active line of a deadleg should be monitored. In a hot piping
system, why does the high point of a deadleg corrode and need to be inspected?
corrosion occurs due to convective currents set up in the deadleg.
What is the best thing to do with deadlegs that are no longer in service?
Remove them.
What are the most common forms of corrosion under insulation (CUI).
localized corrosion of carbon steel and chloride stress corrosion cracking of austenitic stainless steel.
What climatic area may require a very active program for corrosion under insulation?
Warmer, marine locations.
Certain areas and types of piping systems are potentially more susceptible to corrosion under insulation.
Which of the items listed is not susceptible to CUI?
Carbon steel piping systems, operating between 250 degrees F and 600 degrees F.
What location is subject to corrosion under insulation and inspection contributes to it.
Locations where insulation plugs have been removed to permit piping thickness measurements
Soil-to-air (S/A) interfaces for buried piping are a location where localized corrosion may take place. If the
buried part is excavated for inspection, how deep should the excavation be to determine if there is hidden
damage?
6 to 12 inches
At concrete-to-air and asphalt-to-air interfaces of buried piping without cathodic protection, the inspector
should look for evidence that the caulking or seal at the interface has deteriorated and allowed moisture
ingress. If such a condition exists on piping systems over ______ years old, it may be necessary to inspect
for corrosion beneath the surface before resealing the joint
10
An example of service-specific and localized corrosion is
Unanticipated acid or caustic carryover from processes into non-alloyed piping.
Erosion can be defined as?
removal of surface material by action of numerous impacts of solid or liquid particles.
A combination of corrosion and erosion results in significantly greater metal loss than can be expected from
corrosion or erosion alone. This type of loss occurs at:
high-velocity and high-turbulence areas
Environmental cracking of austenitic stainless steels is caused many times by
exposure to chlorides from salt water, wash-up water, etc.
When the inspector suspects or is advised that specific piping circuits may be susceptible to environmental
cracking the inspector should
schedule supplemental inspections
If environmental cracking is detected during internal inspection of pressure vessels, what should the
Inspector do?
The Inspector should designate appropriate piping spools upstream and downstream of the vessel to be
inspected if piping is susceptible to environmental cracking.
If external or internal coatings or refractory liners on a piping circuit are in good condition, what should an
inspector do?
After inspection, if any separation, breaks, holes or blisters are found, it may be necessary to remove
portions of the lining to determine the condition under it.
What course of action should be followed if a coating of coke is found on the interior of a large pipe off a
reactor on a Fluid Catalytic Cracking Unit
Determine whether such deposits have active corrosion beneath them. If corrosion is present, thorough
inspection in selected areas may be required.
Fatigue cracking of piping systems may result from:
excessive cyclic stresses that are often well below the static yield strength of the material.
Where can fatigue cracking typically be first detected?
At points of high-stress intensification such as branch connections.
What are the preferred NDE methods for detecting fatigue cracking.
Liquid penetrant testing, magnetic particle testing and/or possibly acoustic emission testing.
Creep is dependent on:
time, temperature, and stress
An example of where creep cracking has been experienced in the industry is in the problems experienced
with cracking of 1.25% Chrome steels operating at temperatures above _________ degrees F.
900
Brittle fracture can occur in carbon, low-alloy, and other ferritic steels at or below _______ temperatures
ambient
Water and aqueous solutions in piping systems may freeze and cause failure because of the
expansion of these materials
Different types of inspection and surveillance are appropriate depending on the circumstances and the
piping system. Pick the one that does not belong in the following list.
Chemical analysis inspection.
Internal visual inspections are __________ on piping unless it is a large diameter transfer line, duct, catalyst
line or other large diameter piping system.
not normally performed
Name an additional opportunity for a normal non-destructive internal inspection of piping.
When piping flanges are disconnected
Why is thickness measurement inspection performed?
To determine the internal condition and remaining thickness of the piping components.
Who performs a thickness measurement inspection?
The Inspector or examiner
When corrosion product buildup is noted during an external visual inspection at a pipe support contact area
lifting off such supports may be required for inspection. When doing this, care should be:
exercised if the piping is in-service.
Qualified operating or maintenance personnel also may conduct external visual inspections, when:
acceptable to the inspector.
Who would normally report vibrating or swaying piping to engineering or inspection personnel?
Operating personnel
Thermography is used to check for:
hot spots in refractory lined piping systems.
Thickness measurement locations (TMLs) are specific ________ along the piping circuit where inspections are to be made
areas
The minimum thickness at each TML can be located by:
ultrasonic scanning or radiography
Where appropriate, thickness measurements should include measurements at each of _________ on pipe and fittings
four quadrants
Where should special attention be placed when taking thickness measurements of an elbow?
The inside and outside radius
TMLs should be marked on inspection drawings and __________________ to allow repetitive measurements
on the piping system
What is taken into account by an experienced inspector when selecting TML’s?
The patterns of corrosion that would be expected.
In theory, a piping circuit subject to perfectly uniform corrosion could be adequately monitored with ______TML/s
1
More TML’s should be selected for piping systems with any of the following characteristics:
More complexity in terms of fittings, branches, deadlegs, injection points, etc.
Fewer TML’s can be selected for piping systems with any of the following characteristics:
Long, straight-run piping systems.
TML’s can be eliminated for piping systems with the following characteristics:
Extremely low potential for creating a safety or environmental emergency in the event of a leak
What is usually the most accurate means for obtaining thickness measurements on installed pipe larger than nps 1
UT
What thickness measuring technique does not require the removal of some external piping insulation
RT
When ultrasonic thickness measurements are taken above ________ degrees F., instruments couplants,
and procedures should be used that will result in accurate measurements at the higher temperature
150
Typical digital thickness gages may have trouble measuring thicknesses less than ____ inches
0.1250
When pressure testing of piping systems are conducted they shall be performed in accordance with the requirements of?
ASME B31.3.
If a lower pressure test (lower than prescribed by code) is used only for tightness of piping systems, the
_______ may designate the pressure.
owner-user
The preferred medium for a pressure test is ______.
water
If a non-toxic hydrocarbon (flammable) is used as the test medium, the liquid flash point shall be at least
______ degrees F. or greater.
120
Piping fabricated of or having components of 300 series stainless steel should be tested with _________.
steam condensate
For sensitized austenitic stainless steel piping subject to polythionic stress corrosion cracking, consideration
should be given to using _________ for pressure testing
an alkaline-water solution
When a pipe requires post weld heat treatment, when should the pressure test be performed
After any heat treatment.
During a pressure test, where the test pressure will exceed the set pressure of the safety relief valve or
valves on a piping system the safety relief valve or valves should be ______________ when carrying out the test
removed or blanked
If block valves are used to isolate a piping system for a pressure test, what precaution should be taken?
Do not exceed the permissible seat pressure of the valve.
Name a part of a piping system that thickness measurements are not normally routinely taken.
valves
If environmental cracking is found during in-service inspection of welds, who should conduct the untrasonic
shear wave examination, if required?
Industry-qualified UT Examiner (after 2003
If an Inspector finds an imperfection in an original fabrication weld and analysis is required to assess the
impact of the weld quality on piping integrity, which of the following may perform the analysis?
An API 570 Inspector, a CWI Inspector, a Piping Engineer
According to API 570, some welds in a piping system that has been subjected to radiography according to
ASME B31.3:
will not meet random radiograph requirements, but will still perform satisfactorily in-service after being
hydrotested
How should fasteners and gaskets be examined to determine whether they meet the material specifications.
A representative sample of the fasteners and gaskets should be checked to see if their markings are
correct according to ASME and ASTM standards.
When checking flange and valve bonnet bolts for corrosion, what type of NDT is usually used?
VT
What course of action is called for when an inspector finds a flange joint that has been clamped and
pumped with sealant?
Check for leakage at the bolts; if repumping is contemplated, affected fasteners should be renewed.
- All process piping systems must be categorized into different classes. On what are the classifications
selection based?
Potential safety and environmental effects should a leak occur.
- (1). Inspection strategy based on likelihood and consequence of failure is called:
RBI
- (2). An RBI assessment can be used to _______________ the inspection interval limits in Table 1 of
API 570 or the extent of the inspection conducted.
a. increase
b. decrease
- (3). When an RBI assessment is used to increase or decrease inspection intervals, the assessment
shall be conducted on Class 1 systems at a maximum interval of _________ years.
5
Listed below are several examples of a CLASS 1 piping system. Which one does not belong?
Distillate and product lines to and from storage and loading
Of the three classification of piping systems, which includes the majority of unit process and selected off-site
piping?
Class 2
Class 3 piping is described as being in services:
that are flammable but do not significantly vaporize when they leak and are not located in high-activity
areas.
Who establishes inspection interval for thickness measurements, external visual inspections and for internal
and supplemental inspections?
Owner-user or the Inspector.
Thickness measurement inspection should be scheduled based on the calculation of not more than:
one half the remaining life determined from corrosion rates or the maximum interval allowed by API 570 in
Table 1, whichever is shorter.
For External inspections for potential corrosion under insulation (CUI) on Class 1 systems, the examination
should include at least _____ percent of all suspect areas and _____ percent of all areas of damaged
insulation
50, 75
Piping systems that are known to have a remaining life of over ______ years or that are protected against
external corrosion need not have insulation removed for the periodic external inspection
10
For Class 3 piping systems, the examination for corrosion under insulation (CUI) should include at least
_____ percent of all suspect areas.
10
Small bore piping (SBP) that is Class 1 shall be inspected:
to the same requirements as primary process piping
Inspection of small bore piping (SBP) that is secondary and auxiliary (associated with instruments and
machinery) is:
optional.
If an inspector finds threaded small bore piping (SBP) associated with machinery and subject to fatigue
damage, he should:
plan periodically to assess it and consider it for possible renewal with a thicker wall or upgrade it to welded
components.
An eight inch diameter piping system is installed December, 1979. The installed thickness is measured as
0.34”. The required thickness of the pipe is 0.20”. It is inspected on12/83 and the thickness is found to be
0.32”. An inspection 12/87 reveals a loss of 0.01” from the 12/85 inspection. During 12/89 the thickness was
found to be 0.29”. The last inspection was during 12/95 and the thickness was found to be 0.26”. What is
the long term corrosion rate of this system?
0.005”/year
Using the information in question 95, calculate the short term corrosion rate.
0.005”/year
Using the information in questions 95 and 96, determine the remaining life of the system.
12 years
You have a new piping system that has just been installed. It is completely new an no information exists to
establish a corrosion rate. Also, information is not available on a similar system. You decide to put the
system in service and NDT it later to determine the corrosion rate. How long do you allow the system to stay
in service before you take your first thickness readings?
3 months
After an inspection interval is completed and if calculations indicate that an inaccurate rate of corrosion has
been assumed in a piping system, how do you determine the corrosion rate for the next inspection period?
The corrosion rate shall be adjusted to agree with the actual rate found.
If a piping system is made up of unknown materials and computations must be made to determine the
minimum thickness of the pipe, what can the inspector or the piping engineer do to establish the minimum
thickness?
The lowest grade material and joint efficiency in the applicable code may be assumed for calculations
A piping engineer is designing a piping service with high potential consequences if a failure occurs, i.e., a
350 psi natural gas line adjacent to a high density population area. What should he consider doing to
provide for unanticipated situations?
Increase the required minimum thickness.
When evaluating locally thinned areas, the provisions of RP 579 Section ______ should be followed.
5
An Inspector finds a thin area in a fabricated 24” diameter pipe. The thin area includes a longitudinal weld
in the pipe and is 10 feet long and 2 foot circumferentially. Calculations show that with 0.85 joint factor,
the pipe must be repaired, renewed, etc. or the pressure in the pipe must be lowered. The owner does
not want do any hot work on the pipe and he does not wish to lower the pressure. What other course
could be followed, per API 570?
Conduct an FFS per RP 579.
Piping stress analysis is done during the system’s original design. How can the inspector make use of
stress analysis information?
It can be used to concentrate inspection efforts at locations most prone to fatigue or
creep damage, and to solve vibration problems
You are inspecting a piping system. You find a significant loss of material (a major increase of corrosion
rate) in gas oil piping (used as reboiler oil, temperature 500 degrees F.) on an Fluid Catalytic Cracking
Unit. What is the best course of action for you to take?
It shall be reported to the owner-user for appropriate action.
The ___________ shall maintain appropriate permanent and progressive records of each piping system
covered by API 570.
owner-user
When making repairs and alterations to piping systems the principles of ________ or the code to which the
piping system was built shall be followed.
ASME B31.3
Repair and alteration work must be done by a repair organization as defined in API 570 and must be
authorized by the _________ prior to its commencement.
inspector
Authorization for alteration work to a piping system may be given by the inspector after:
consultation with, and approval by a piping engineer.
A repair procedure involving welding requires that the root pass of the weld be inspected before continuing
the weld. A “hold” on the repair is required at this point. Who designates this “hold”?
An API 570 inspector.
What type of repairs and procedures may the inspector give prior general authorization to continue
(provided the inspector is satisfied with the competency or the repair organization?
limited or routine repairs and procedures
Who approves all proposed methods of design, execution, materials, welding procedures, examination,
and testing of in-service piping?
The inspector or the piping engineer, as appropriate
Who must give approval for any on-stream welding?
owner-user.
An inspector finds a crack in the parent metal of a pipe adjacent to a support lug. The pipe was being
inspected after a 5 year run. Before repairing the he should:
Consult with the piping engineer to identify and correct the cause of the crack.
A full encirclement welded split sleeve designed by a piping engineer may be applied over a damaged or
corroded area of a pipe. This is considered a temporary repair. When should a permanent repair be made?
A permanent repair must be made at the next available maintenance opportunity
What type of defect, corrosion, pitting and/or discontinuity should not be repaired by a full encirclement
welded split sleeve?
A longitudinal crack.
If a repair area is localized (for example, pitting or pin-holes) and the specified minimum yield strength
(SMYS) of the pipe is not more than ___________ psi, a temporary repair may be made by fillet welding a
properly designed plate patch over the pitted area.
40,000 psi
Insert patches (flush patches may be used to repair damaged or corroded areas of pipe if several
requirements are met. One of these is that an insert patch (flush patch) may be of any shape but it shall
have rounded corners with ______ minimum radii.
1’’
An inspector finds a pin-hole leak in a weld during an on-stream inspection of a piping system. A
permissible temporary repair is:
the installation of a properly designed and fabricated bolted leak clamp.
Temporary leak sealing and leak dissipating devices shall be removed and the pipe restored to original
integrity:
at a turnaround or other appropriate time.
Which of the following is NOT an item for consideration by an inspector when a leak sealing fluid
(“pumping”) is used for a temporary leak seal repair.
Consider the pressure testing of the piping in question.
Any welding conducted on piping components in operation must be done in accordance with:
API Publication 2201
All repair and alteration welding to piping systems shall be done in accordance with the:
principles of ASME B31.3 or the code to which it was built.
Welders and welding procedures used in making piping repairs, etc. shall be qualified in accordance with:
ASME B31.3 or the code to which the piping was built.
The repair organization responsible for welding shall maintain records of welding procedures and welder
performance qualifications. These records shall be available to the inspector:
before the start of welding.
Preheating to not less than ________ degrees F. may be considered as an alternative to post weld heat
treatment for alterations or repairs of P-1 piping initially post weld heat treated as a code requirement (may
not be used if the piping was post weld heat treated due to environmental cracking prevention).
300
When using local PWHT as a substitute for 360-degree banding on local repairs of PWHT’d piping, which
of the following items is NOT considered?
The locally PWHT’d area of the pipe must be RT’d or UT’d
Piping butt joints shall be:
full-penetration groove welds.
When should piping components that need repair be replaced?
When repair is likely to be inadequate
Fillet welded patches (lap patches) shall be designed by:
the piping engineer.
Fillet welded lap patches (overlay patches) shall have:
rounded corners
Materials used in making welding repairs or alterations _______ be of known weldable quality
shall
Acceptance of a welded repair or alteration shall include _______ in accordance with the applicable code
and the owner-user’s specification, unless other wise specified in API 570
Nondestructive examination
After welding is completed on a repair or alteration, __________________ in accordance with API 570
shall be performed if practical and deemed necessary by the inspector
a pressure test
When are pressure tests normally required?
Pressure tests are normally required after alterations and major repairs
When a pressure test is not necessary or practical, what shall be utilized in lieu of a pressure test?
Nondestructive examination.
Substituting special procedures in place of a pressure test after an alteration or repair may be done only
after consultation with:
the inspector and the piping engineer
When it is not practical to perform a pressure test of a final closure weld that joins a new or replacement
section of piping to an existing system, several requirements shall be satisfied. Which of the following is
NOT one of the requirements.
The closure weld is a full-penetration fillet weld between a weld neck flange and standard piping component
or straight sections of pipe of equal diameter and thickness, axially aligned, and of equivalent materials.
For design cases up to Class 150 and 5000 F., slip-on flanges are acceptable alternates.
Which of the following is NOT a requirement for rerating a piping system by changing the temperature or
the MAWP.
The existing pressure relieving devices are still in place & set as they were originally.
Why is inspection of buried process piping (not regulated by DOT)different from other process piping
inspection?
Significant external deterioration can be caused by corrosive soil conditions.
Indications of leaks in buried piping may include several indications. Which of the ones listed below is NOT
one of the indications.
Water standing on the pipeline right-of-way.
Corrosion cells can form on both bare and coated pipe where bare steel contacts the soil. How can these
cells be detected?
The potential at the area of corrosion will be measurable different than other areas and a close-interval
potential survey can detect the location of corrosion.
A pipe coating holiday survey is used to locate coating defects on coated pipes. It can be used on newly
constructed pipe systems to ensure that the coating is intact and holiday-free. More often it is used on
buried pipe to:
evaluate coating serviceability for buried piping that has been in-service for a long time
Cathodically protected buried piping should be monitored __________ to assure adequate levels of
protection.
regularly
If an “intelligent pigging” system is used to inspect buried piping, what type of bends are usually required in
the piping system?
Five diameter bends.
How often should above-grade visual surveillance of a buried pipeline right-of-way be made?
Approximately 6 month intervals.
How often should poorly coated pipes with inconsistent cathodic protection potentials have a pipe-to-soil
potential survey made?
Every 5 years.
On buried piping, what is the frequency of pipe coating holiday surveys?
It is usually based on indications that other forms of corrosion control are ineffective.
For piping buried in lengths greater than ________ feet and not cathodically protected, evaluation of soil
corrosivity should be performed at 5-year intervals.
100
If buried piping is cathodically protected, the system should be monitored at intervals in accordance with
Section 10 of NACE RP0169 or Section 9 of API RP 651. API RP 651 specifies _________ interval.
annual
Buried piping inspected periodically by excavation shall be inspected in lengths of ________ feet at one or
more locations judged to be most susceptible to corrosion.
6 to 8
After excavation of buried piping, if inspection reveals damaged coating or corroded piping:
additional piping shall be excavated until the extent of the condition is identified.
If buried piping is contained inside a casing pipe, the casing should be:
inspected to determine if water and/or soil has entered the casing
An alternative or supplement to inspection of buried piping is leak testing with liquid at a pressure at least
____ % greater than the maximum operating pressure at intervals 1/2 the length of those shown in Table
9-1 of API 570 for piping not cathodically protected and at the same intervals as shown in Table 9-1 for
cathodically protected piping.
10
The leak test for buried piping should be for a period of ______ hours.
8
The leak test for a 8” diameter buried piping system is 300 psi. After 7 hours, the pressure reads 273 psi.
What should the inspector do?
The piping should be visually inspected externally and/or inspected internally to find the leak and assess
the extent of corrosion.
A buried piping system that is not cathodically protected has to have an inspection interval set. The soil
resistivity is checked and found to be 3400 ohm-cm. As the inspector, what interval of would you set?
10 years
Buried piping also may be surveyed for integrity by removing the line from service and performing a leak
test. This inspection method typically involves pressurizing the line with a __________ , allowing time for
the ___________ to diffuse to the surface, and surveying the buried line with a gas-specific detector to
detect the __________.
tracer gas (such as helium or sulfur hexafluoride)
Repairs to coatings on buried piping may be tested using:
a high-voltage holiday detector
If buried piping leaks are clamped and reburied,:
a record of the location and the date of installation shall be maintained
A 10” diameter piping system with 4” diameter and 6” diameter reinforced branch connections is to have
changes made to it. Which of the following is considered an alteration?
A new 8” diameter reinforced branch connection is installed
Which of the following would not be classified as an applicable code to which a piping system was built?
ASTM A-20
Which of the inspection agencies listed below is
NOT
an authorized inspection agency
as defined in API570?
ASTM inspection organization
An
authorized piping inspector
is an employee of an authorized inspection agency who is qualified toperform the functions specified in API 570. Which individual listed below is
not
usually an
authorized piping inspector
An NDE examiner
Which of the following qualifies as
auxiliary piping
?
pump seal oil lines
CUI stands for:
corrosion under insulation
Deadlegs legs of a piping system are:
sections that normally have no significant flow
A defect is an imperfection of a type or magnitude exceeding the ______ criteria.
acceptable
The design temperature of a piping system component is the temperature at which, under the coincidentpressure, the ______________________________________ is required.
greatest thickness or highest component rating
An examiner is a person who _________ the inspector
assists
Hold point is a point in the repair or alteration process beyond which work may not proceed until the _______ _________ has been performed and documented
required inspection
What is an imperfection?
It is a flaw or discontinuity noted during inspection that may be subject to acceptance
_____________ : is a response or evidence resulting from the application of a nondestructive evaluation technique
indication
What are points where chlorine is introduced in reformers, water is added in overhead systems, etc. called
injection points
What is the loss of ductility and notch toughness in susceptible low-alloy steels such as 1.25 and 2.5 Cr.,due to prolonged exposure to high-temperature service called?
temper embrittlement
Secondary process piping is small-bore (less than or equal to _______) process piping downstream ofnormally closed block valves
NPS 2
A test point is an area defined by a circle having a diameter not greater than _____ inches for a linediameter not exceeding 10 inches or not greater than ______ inches for larger lines
2, 3
When making a repair utilizing a welded full encirclement repair sleeve and the sleeve material isdifferent from the pipe material, you should
consult the piping engineer.
What type of electrode should be used when welding a full encirclement repair sleeve?
low-hydrogen electrode
Which of the following welding electrodes is low-hydrogen?
E7016
. When welding a small repair patch, the diameter of electrodes used should not exceed:
5/32’’
