API 570 Questions

                                                     API 570 Questions

1.In the Barlow formula for determining pipe thickness, the term S stands for

  • Internal design gage pressure of the pipe in psi
  • Pressure design strength for internal pressure, in psi
  • Allowable unit stress at the design temperature, in psi
  • Maximum strain at the average operating temperature, in psi


2.At low pressure and temperature, the thickness determined by the Barlow formula may  be so small that  the pipe would have _________________ structural strength

  • Adequate
  • Insufficient
  • Ample
  • Good


3.A seamless NPS 12, A-106 Grade A pipe operators at 300 degrees F and 941 psi. The allowable stress is 16000 psi. Using the Barlow Equation, determine the thickness required for these conditions

  • 0.375”
  • 0.750”
  • 0.353”
  • 0.706”

4.A seamless NPS6, A-106 Grade A pipe operators at 300 degrees F and 941 psi. The allowable stress is 16000 psi . The owner-user specified that the pipe must have 0.1” allowed for corrosion allowance. Using the Barlow Equation, determine the thickness required for these conditions

  • 0.706”
  • 0.277”
  • 0.195”
  • 0.295”

5.A seamless NPS8, A-53 Grade B pipe operators at 700 degrees F and 700 psi. The allowable stress is 16500 psi . The pipe has been in service for 6 years. The original wall thickness of the pipe was 0.375”. The pipe wall now measure 0.30” Considering no structural requirements, estimate how long the piping can continue to operate and not be below the minimum thickness

  • 4.68 years
  • 9.8 years
  • 0 years; pipe now below minimum
  • 10.42 years


6.An Inspector finds a thin area in the body of a NPS 8 (8.625” O.D.) 600# gate valve. The valve’s body is made from ASTM A216 WCB material. The system operates at 700 psi and 750 degrees F. Using a corrosion allowance of 0.125”, what thickness must be present in order to continue to safely operate ( Hint 1.5 x 8.635 x 600/ 2 X 7000  +  0.125 )

  • 0.48”
  • 0.68”
  • 0.51”
  • 0.43”


7.If corrosion or erosion is anticipated for a valve, what should be done prior to installing the valve?

  • Severance thickness determinations should be made when the valves are installed so that the fretting rate and metal ruination can be determined
  • Retirement thickness measurement should be made after installation so that the fatigue rate and metal loss can be determined
  • Reference thickness measurements should be made when the valves are installed so that the corrosion rate and metal loss can be determined
  • Retina measurements of the macula should be made when the iris’ are installed so the optical rate and losses of perception can be determined



8.Which of the items listed below would NOT normally be contained in inspection records of piping?

  • Original date of installation, the specifications and strength levels of the materials used
  • Original vessel hydrotest pressures and conditions that the tests were performed  under
  • Original thickness measurement and the locations and dates of all subsequent readings
  • Calculated retirement thicknesses


9.Accurate records of a piping system make possible an evaluation of _____________ on any piping, valve or fitting

  • Computerization
  • Security and continuity
  • Cost and competency
  • Service life


10.You are working as an inspector. While reviewing a tabulation of thickness  data on a section of piping in non-corrosive or very low corrosive service, you  find the initial thickness reading of an inspection point to be 0.432” and marked nominal on a NPS 6 pipe. At the next inspection 12 months later you find a reading by ultrasonics of 0.378” at the same point. Twelve months later UT readings were taken and the thickness at the point was still 0.378” what would this mean to you?

  • No measurement was taken originally, the nominal thickness  was listed and the piping probably had an under-tolerance of 12.5%
  • There was an error made by the inspector at the installation or the inspector who UT” d the piping at the next inspection made an error
  • The UT machine that the inspector used during the 12 month inspection after installation was defective and not reading correctly
  • The pipe contractor or the installer put the wrong schedule piping in service


11.You are working as an inspector. While reviewing a tabulation of thickness data on a section of piping, you find the letter “C” marked under a column headed by the word METHOD. What does the “C” indicate?

  • The  inspection temperature of the pipe was COLD
  • The thickness measurement was made by an inspector with  ID OF “C”
  • The thickness measurement was taken with calipers
  • The thickness measurement was CONFIRMED  by a second party


12.Which of the following is not an important function of an accurate sketch?

  • Assist in determining future locations that urgently require examinations
  • Identifying systems and circuits in terms of location,  size, material etc
  • Serve as field data sheets
  • None of the above


13.The Wenner 4-Pin methods, the soil bar, and the soil box do not represent  methods of determining

  • Holidays
  • Pipe-to-soil potentials
  • Cathodic protection acceptability
  • All of the above


14.The total resistivity for a wenner 4-Pin test that utilizes pins spaced 2 feet apart and a 6 “R” factor is:

  • 2298 ohm/cm
  • 3500 ohm/cm
  • 6000 ohm/cm
  • 8000 ohm/cm


15.Which of the following is not a consideration when using a soil bar?

  • Using a standard prod bar
  • Avoiding the addition of water
  • Applying pressure on the soil bar after injection
  • None of the above


16.Which of the following is a consideration when using a soil box

  • Depth of pins less than 4% of spacing
  • Ensuring the soil has dried out before testing
  • Avoiding contamination of the sample during handling and storage
  • All of the above
1 C
2 B
3 A
4 A
5 B
6 C
7 C
8 B
9 D
10 A
11 C
12 D
13 D
14 A
15 D
16 C


API 510 Questions | API Training Institute in Trichy

API 510 Questions

1.A PQR was qualified in SG position using a new welder. But production welding is to be done by   the same welder in 3G position. Which of the following are applicable as a minimum?

  • Both procedure and welder shall be re-qualified in 2G position.
  • The qualified procedure can be used, only welder needs to be re-qualified in 3G position.
  • The welder is qualified, but the procedure needs re­-qualification.
  • Both procedure and welder need not be re-qualified.

2.A procedure is required with preheat temp = 2S0oF. Two WPS were made based on this PQR. All other parameters being same WPS (A) showed preheat temp = 280°F and WPS (B) showed preheat temp = 140°F, will you:

  • Reject (A) & (B)
  • Accept (A) only
  • Accept (B) only
  • Accept both

3.In a certain PQR for SMAW, the electrodes used for all passes were of AWS classification (E7018). Corresponding WPS also showed filler materials as E 7018. Now the manufacturer proposes to change the filler material in WPS to E 701S. Will you ask manufacturer to:

  • Quality new PQR with E 7015 electrodes.
  • Revise only WPS showing the change from E 7018 to E7015 and submit WPS as a new    revision.
  • Revise only the PQR showing the change and resubmit for approval.
  • Revise both WPS and PQR showing the change and resubmit for approval.

4.A PQR in GTAW process was qualified with PWHT with A 516 grade 70 materials, ¾” thick. The thickness for production welds is 1.0”, but without PWHT. The manufacturer claims that same PQR will be O.K. What is your assessment?

  • It qualifies required conditions hence no new PQR is required.
  • It qualifies thickness but not It does not qualify “No PWHT” condition, hence new PQR is   required.
  • It qualifies “no PWHT” condition, but not thickness. New PQR is required.
  • It does not qualify both thickness as well as “No PWHT” – condition, hence new PQR is    required. ­

5.For 515 grade 60 material, the following results were obtained for two tensile test specimen during   a PQR qualification.

Specimen T1: failed in B.M. at 57,400 psi

Specimen T2: failed in weld metal, at 59,500 psi

Your assessment is:

  • PQR test is OK since both are within acceptance criteria
  • PQR test is rejected as both T1 and T2 are not within the acceptance criteria
  • PQR in rejected because T1 is OK but T2 has failed
  • PQR in rejected because T1 is failed thoughT2 is OK

6.A procedure is qualified with Base metal THK. = 20mm. Two WPS were made based on this PQR. Other parameters being same, WPS (A) showed Base Metal Thk. = 38 mm and WPS (B) showed Base Metal Thk. = 6mm.

Your assessment is:

  • Reject (A) & (B)
  • Accept (A) only
  • Accept (B) only
  • Accept both

7.A welder has made 25 SMAW groove welds, but the guided bend test for the welder’s qualification was never performed. In order to avoid cutting out all of the production welds made by this welder, which of the following minimum steps would be taken to validate the qualification?

  • Radiograph the welder’s first production weld and accept the qualification based on acceptable weld quality by radiography.
  • There is no alternative to qualifying a welder by the guided bend test.
  • Have the welder prepare a test coupon and have the bend test done on that. If bend test is okay,    accept the welds already made.
  • Radiograph all 25 welds, regardless of the governing specifications for sample selection.

8.In a radiographic examination of butt weld (Thk= 3.5 in.) the Geometric un-sharpness shall not exceed?

  • 0.02″
  • 0.04″
  • 0.03″
  • None of above

9.Select suitable Hole Type (Source Side) penetrameter for following weld joint:

Base Mertal Thk. = 7/8”

Backing Strip Thk. = 3/16”

Weld Re-enforcement Thk. = 1/8”

  • No. 20
  • No. 25
  • No. 30
  • None of the above

10.If type of penetrameter in above question is changed to wire type what shall be the wire designation (wire diameter In Inch)?

  • 0.025 dia. (No.10)
  • 0.016 dia. (No. 8)
  • 0.032 dia. (No.11)
  • None of the above

11.For steel plates and welds to be checked by LPI what shall be the penetration time for the Penetrant?

  • 10 min for weld, 5 min for plate
  • 5 min for both
  • 10 min for both
  • 5 min for weld, 10 min for plate

12.After applying the developer the examiner checked four welds for surface defects after following period, weld A after 5 minute, weld B after 10 minutes, weld C was checked after 30 minutes and welds D after 65 minutes. Which of the welds were checked wrongly?

  • Weld A and B
  • Weld C and D
  • Weld D only
  • Weld A and D

13.For MT examination by Prod Technique the spacing between prods shall be between?

  • 4 inch to 12 inch
  • 4 inch to 10 inch
  • 3 inch to 10 inch
  • 3 inch to 8 inch

14.Calculate estimated inspection period for external and internal inspection for a vessel whose remaining life is estimated as 12 years?

  • Internal = 6 years, external = 10 years
  • Internal = 6 years, external = 5 years
  • Internal = 5 years, external = 10 years
  • None of the above

15.As per WPS the material used is SAS16 Gr.70 and the electrode used is E-7018. What are the P. No. and F No.?

  • 1 and 4
  • 4 and 1
  • 2 and 4
  • 4 and 2
1 D
2 B
3 B
4 B
5 C
6 D
7 A
8 B
9 B
10 D
11 D
12 D
13 D
14 B
15 A

API 570 Questions | API Training Institute|ESL INDUSTRIAL SUPPORT SERVICES


API 570 Questions

1)         API 570 covers inspection, repair alteration, and re-rating procedures for metallic piping systems that __________.


  1. a) Are being fabricated
  2. b) Does not fall under ASTM B31.3
  3. c) Have been in-service
  4. d) Has not been tested


2)         API 570 was developed for the petroleum refining and chemical process industries.


  1. a) It shall be used for all piping systems.
  2. b) It may be used, where practical, for any piping system.
  3. c) It can be used, where necessary, for steam piping.
  4. d) It may not be used unless agreed to by all parties.


3)         API 570 __________ be used as a substitute for the original construction requirements governing a piping system before it is placed in-service.


  1. a) Shall not b)         Should              c)         May                  d)         Can


4)         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?


  1. a) Raw, intermediate, and finished petroleum products
  2. b) Water, steam condensate, boiler feed water
  3. c) Raw, intermediate, and finished chemical products
  4. d) Hydrogen, natural gas, fuel gas, and flare systems


5)         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?


  1. a) Water                         b)         Catalyst lines
  2. c) Steam                         d)         Boiler feed water


6)         The __________ shall be responsible to the owner-user for determining that the requirements of API 570 for inspection, examination, and testing are met.


  1. a) Piping Engineer             b)         Inspector
  2. c) Repair Organisation             d)         Operating Personnel


7)         Who is responsible for the control of piping system inspection programs, inspection frequencies and maintenance of piping?


  1. a) Authorised Piping Inspector                   b)         Owner-user
  2. c) Jurisdiction                                           d)         Contractor


8)         An authorised API 570  piping inspector shall have the following qualifications. Pick the one that does not belong in this list:


  1. a) Four years of experience inspecting in-service piping systems
  2. b) High school education plus 3 years of experience in the design, construction, repair, operation, or inspection of piping systems
  3. c) Two year certificate in engineering or technology plus 2 years of experience in the design, construction, repair, operation, or inspection of piping systems.
  4. d) Degree in engineering plus one year experience in the design, construction, repair, operation, or inspection of piping systems.



9)          Risk based inspections include which of the following:


  1. a) Likelihood assessment              b)         Consequence analysis
  2. c) Operating and inspection histories         d)         All of the above


10)        An RBI assessment can be used to alter the inspection strategy provided:


  1. a) The degradation methods are identified  b)         The RBI is fully documented.
  2. c) A third party conducts the RBI               d)         Both A and B above


11)        Which one of the following is not a specific type of an area of deterioration?


  1. a) Rectifier performance                b)         Injection points
  2. c) Deadlegs                                              d)         Environmental cracking


12)        Injection points subject to accelerated or localised corrosion may be treated as __________.


  1. a) The focal point of an inspection circuit
  2. b) Separate inspection circuits
  3. c) Piping that must be renewed on a regular schedule
  4. d) Locations where corrosion inhibitors must be used


13)        The recommended upstream limit of inspection of an injection point is a minimum of:


  1. a) 12 feet or 3 pipe lengths whichever is smaller
  2. b) 12 inches or 3 pipe diameters whichever is smaller
  3. c) 12 inches or 3 pipe diameters whichever is greater
  4. d) 12 feet or 3 pipe lengths which is greater


14)        The recommended downstream limit of inspection of an injection point is a minimum of


  1. a) Second change in flow direction past the injection point, or 25 feet beyond the first change in flow direction whichever is less
  2. b) Second change in flow direction past the injection point, or 25 feet beyond the first change in flow direction whichever is greater
  3. c) Second change in flow direction past the injection point, or 25 inches beyond the first change in flow direction whichever is less
  4. d) Second change in flow direction past the injection point, or 25 inches beyond the first change in flow direction whichever is greater.


15)        Select thickness measurement locations (TMLs) within injection point circuits subjected to localised corrosion according to the following guidelines. Select the one that does not belong.


  1. a) Establish TMLs on appropriate fittings within the injection point circuit.
  2. b) Establish at least one TML at a location at least 25 feet beyond the downstream limit of the injection point.
  3. c) Establish TMLs on the pipe wall at location of expected pipe wall impingement or injected fluid.
  4. d) Establish TMLs at both the upstream and downstream limits of the injection point circuit.


16)        What are the preferred methods of inspecting injection points ?


  1. a) Radiography and / or ultrasonics                        b)   Hammer test and / or radiograph
  2. c) Ultrasonics and / or liquid penetrant       d)   Liquid penetrant and / or eddy current.


17)        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.


  1. a) 10 inches, 20                                         b)         12 feet, 10
  2. c) 12 inches, 10                                         d)         10 feet, 10


18)        Why should deadlegs in piping be inspected?


  1. a) API 510 mandates the inspection of deadlegs
  2. b) Acid products and debris build up in deadlegs
  3. c) The corrosion rate in deadlegs can vary significantly from adjacent active piping.
  4. d) Caustic products and debris build up in deadlegs.


19)        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?


  1. a) Corrosion occurs due to directed currents set up in the deadleg
  2. b) Erosion occurs due to convective currents set up in the deadleg.
  3. c) Corrosion occurs due to convective currents set up in the deadleg
  4. d) Erosion occurs due to directed currents et up in the deadleg


20)        What is the best thing to do with deadlegs that are no longer in service?


  1. a) Ultrasonically inspect often                    b)         Radiograph often
  2. c) Inspect often                                         d)         Remove them


21)        What are the most common forms of corrosion under insulation (CUI).


  1. a) Localised corrosion of non-ferrous metals and chloride stress corrosion cracking of carbon steel.
  2. b) Localised corrosion of chrome-moly steel and chloride stress corrosion cracking of ferritic stainless steel.
  3. c) Localised corrosion of carbon steel and chloride stress corrosion cracking of austenitic stainless steel
  4. d) Localised corrosion of nickel-silicon alloy and caustic stress corrosion of austenitic stainless steel


22)        What climatic area may require a very active program for corrosion under insulation?


  1. a) Cooler northern continent locations. b)   Cooler direr, mid-continent locations
  2. c) Warmer, marine locations                       d)        Warmer drier, desert locations


23)        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?


  1. a) Areas exposed to mist over-spray from cooling water towers.
  2. b) Carbon steel piping systems that normally operate in-service above 250 degrees but are in intermittent service.
  3. c) Deadlegs and attachments that protrude from insulated piping and operate at a different temperature than the temperature of the active line.
  4. d) Carbon steel piping systems, operating between 250 degrees F and 600 degrees F.


24)        What location is subject to corrosion under insulation and inspection contributes to it?


  1. a) Locations where pipe hangers and other supports exist.
  2. b) Locations where insulator has been stripped to permit inspection of the piping.
  3. c) Locations where insulation plugs have been removed to permit piping thickness measurements.
  4. d) Locations where there is damaged or missing insulation jacketing.


25)        Soil-to-air (S/A) interfaces for buried piping are a location where localised 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?


  1. a) 12 to 18 inches  b)         6 to 12 inches
  2. c) 12 to 24 inches  d)         6 to 18 inches


26)        At concrete-to-air and asphalt-to-air interfaces of buried piping without cathodic protection, the inspector 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.


  1. a) 8 b)         5                      c)         15                     d)         10

27)        An example of service-specific and localised corrosion is:-


  1. a) Corrosion under insulation in areas exposed to steam vents
  2. b) Unanticipated acid or caustic carryover from processes into non-alloyed piping
  3. c) Corrosion in deadlegs
  4. d) Corrosion of underground piping at soil-to-air interface where it ingresses or egresses.


28)        Erosion can be defined as:


  1. a) Galvanic corrosion of a material where uniform losses occur
  2. b) Removal of surface material by action of numerous impacts of solid or liquid particles
  3. c) Gradual loss of material by a corrosive medium acting uniformly on the material surface
  4. d) Pitting on the surface of a material to the extent that a rough uniform loss occurs


29)        A combination of corrosion and erosion results in significantly greater metal loss that can be expected from corrosion or erosion alone. This type of loss occurs at:


  1. a) High-velocity and high-turbulence areas
  2. b) Areas where condensation or exposure to wet hydrogen sulphide or carbonates occur
  3. c) Surface-to-air interfaces f buried piping
  4. d) Areas where gradual loss of material occurs because of a corrosive medium


30)        Environmental cracking of austenite stainless steels is caused many times by:-


  1. a) Exposing areas to high-velocity and high-turbulence streams
  2. b) Excessive cyclic stresses that are often very low
  3. c) Exposure to chlorides from salt water, wash-up water, etc.
  4. d) Creep of the material by long time exposure to high temperature and stress