BODY OF KNOWLEDGEAPI-510 PRESSURE VESSEL INSPECTOR 1

API Authorized Pressure Vessel Inspectors must have a broad knowledge base relating to maintenance, inspection, repair, and alteration of pressure vessels. The API Authorized Pressure Vessel Inspector Certification Examination is designed to determine if individuals have such knowledge. The following is a list of specific topics in which the API Authorized Pressure Vessel Inspector should be knowledgeable.

 

To determine whether the applicants have this broad base of inspection knowledge, a minimum of one question from each category listed within this Body of Knowledge (BOK) will be included on the API certification examination. Only inspection information covered in one of the references outlined in this body of knowledge will be utilized for the examination questions.

 

Questions may be taken from anywhere within each document in this BOK, unless specifically excluded herein.

 

In the event that specific sections of a document are listed as excluded– all other sections within that document are included.

 

In some cases specific paragraphs or sections, such as the example shown below, are included as an aid to the candidate. This is not intended to exclude other paragraphs.
        For example: In the “Corrosion Rate and Inspection Intervals” section of this BOK  (Section A, sub-section 1), 

          it states:
                     The Inspector must be able to calculate:   

                        a) Metal Loss (including corrosion averaging) (API-510, Para 7.4)
                        
                     This means that the metal loss calculation will be found in paragraph 7.4. It does not mean that

                      other paragraphs in that section are excluded.

 

The examination consists of two parts. The closed-book part tests the candidate on knowledge and tasks requiring everyday working knowledge of API Standard 510 and the applicable reference documents. The open-book portion of the examination requires the use of more detailed information that the inspector is expected to be able to find in the documents, but would not normally be committed to memory.

 

 

REFERENCE PUBLICATIONS:

A. API Publications:
API 510, Pressure Vessel Inspection Code
API RP 571, Damage Mechanisms Affecting Equipment in Refining Industry
API RP 572, Inspection of Pressure Vessels including Annex B, (all other Annexes are excluded)
API RP 576, Inspection of Pressure-Relieving Devices
API RP 577, Welding Inspection and Metallurgy

 

B. ASME Publications:
Section V, Nondestructive Examination
Section VIII, Division 1, Rules for Constructing Pressure Vessels
Section IX, Qualification Standard for Welding, Brazing and Fusion Procedures; Welders; Brazers; and Welding, Brazing and Fusing Operators
Note: Refer to the Publications Effectivity Sheet in the application package for a list of specific editions, addenda, and supplements of the reference publications that are effective for your exam date.

 

I. THICKNESS MEASUREMENTS, INSPECTION INTERVALS AND VESSEL INTEGRITY

 

A.   Code calculation questions will be oriented toward existing pressure vessels, not new pressure vessels. API Authorized Pressure Vessel Inspectors should be able to check and perform calculations relative to in-service deterioration, repairs, rerates, or alterations. Only internal pressure loadings will be considered for the API 510 examination. Note: Dimensions, pressures and temperatures in exam items are supplied in SI units (metric) and the US customary units (inches, feet, psi, etc.) where applicable, to assist all candidates’ understanding.

 

The following categories describe the minimum necessary knowledge and skills:

 

1. CORROSION RATES AND INSPECTION INTERVALS
The Inspector should be able to take inspection data and determine the internal and external inspection intervals.
The Inspector must be able to calculate:
a) Metal Loss (including corrosion averaging) (API 510, Para 7.4)
b) Corrosion Rates (API 510, Para 7.1)
c) Remaining Corrosion Allowance (API 510, Para 7.1)
Remaining Corrosion Allowance = tactual – trequired
d) Remaining Service Life (API 510, Para 7.2)
e) Inspection Interval (API 510, Section 6)
The formulas for performing the above calculations and rules for setting the inspection intervals may be "closed-book” during the examination.

 

2. JOINT EFFICIENCIES

 

The inspector must be able to determine the joint efficiency "E" of a vessel weld. Inspector should be able to determine:
a) Weld Joint Categories (ASME Section VIII, UW-3);
b) Type of radiography (full, spot, or none) performed basis the nameplate markings (RT-1, RT-2, etc.); (UW -11)
c) Joint efficiency by reading Table UW-12;
d) Joint efficiency for seamless heads and vessels Sections per UW-12 (d); and
e) Joint efficiency for welded pipe and tubing per UW-12 (e).
Determining joint efficiency may be part of the internal pressure problem since joint efficiency "E" is used in the formulas for determining required thickness or Vessel Part MAWP.

 

3. STATIC HEAD
The inspector must be able to compensate for the pressure resulting from static head. All static head will be based upon a Specific Gravity of 1.0. The inspector should be able to:
a) List the static head/pressure conversion factor (0.433 psi/ft);
b) Know the difference between vessel MAWP and vessel part MAWP (UG-98);
c) Calculate static head pressure on any vessel part;
d) Calculate total pressure (MAWP + static head) on any vessel part;
e) Calculate maximum vessel MAWP given vessel parts MAWP and elevations
Static head calculations may also be required during the internal pressure calculations if static head data is given in the examination problem.

 

4. INTERNAL PRESSURE

The inspector should be able to determine:
a) The required thickness of a cylindrical shell based on circumferential stress given a pressure (UG-27(c)(1));
b) The required thickness of a spherical shell based on circumferential stress given a pressure ( UG-27(d)
c) The vessel part MAWP for a cylindrical shell based on circumferential stress given a metal thickness (UG-27(c)(1));
d) The required thickness of a head (ellipsoidal, and hemispherical) given a pressure. (UG-32 (c), and (e))
e) The vessel part MAWP for a head (ellipsoidal, and hemispherical) given a metal thickness. (UG-32 (c), and (e)).
f) Whether a head (ellipsoidal or hemispherical) meets Code requirements given both pressure and metal thickness. (UG 32(c) and (e)).
The inspector should also be able to compensate for the corrosion allowance: add or subtract based on requirements of the examination problem. The Section VIII, Appendix 1 formula for cylinders, which is based on outside diameter, can be used. The Appendix 1 formulas for non-standard heads will not be required.

 

5. EXTERNAL PRESSURE
The inspector should be knowledgeable of the rules for design of shells and tubes under external pressure (UG-28). The inspector will not be required to perform external pressure calculations.

 

6. PRESSURE TESTING
The inspector should be able to:
a) Calculate a test pressure compensating for temperature. (UG-99 & UG-100)
b) Be familiar with the precautions associated with hydrostatic and pneumatic testing, such as minimum test temperatures, protection against overpressure etc.
c) Be familiar with all steps in a hydrotest procedure (UG99 and UG100)
d) Be familiar with all steps in a pneumatic test procedure (UG-100 and UG-102)

 

7. IMPACT TESTING
a) The inspector should understand impact testing requirements and impact testing procedure (UG-84)
b) The inspector should be able to determine the minimum metal temperature of a material which is exempt from impact testing (UG-20 (f), UCS-66, UCS-68(c).)

 

8. WELD SIZE FOR ATTACHMENT WELDS AT OPENINGS
The inspector must be able to determine if weld sizes meet Code requirements. The inspector should be able to:
a) Convert a fillet weld throat dimension to leg dimension or vice versa, using conversion factor (0.7); and
b) Determine the required size of welds at opening (UW-16)

 

9. NOZZLE REINFORCEMENT
The inspector should understand the key concepts of reinforcement, such as replacement of strength removed and limits of reinforcement.
B. The following are typical ASME code engineering requirements that API certification candidates will NOT be expected to know for purposes of the certification examination.

 

1. Required thickness calculations for wind, earthquake, and other secondary stress loadings;
2. Supplementary design formulas and calculations for non-cylindrical shell components;
3. External pressure calculations (but should understand the rules governing external pressure noted in Section 5);
4. Nozzle calculations for external loads;
5. Flange calculations;
6. Brazing requirements;
7. Ligament calculations;
8. Stayed flat heads and sizing of stays;
9. Tubesheet calculations (stayed or unstayed) and tube to tubesheet joints and loads;
10. Relief valve sizing;
11. Lifting lug and other structural type calculations;
12. Proof testing requirements;
13. Required inspections for new construction, except as they apply to alterations and repairs;
14. Zick analysis;
15. Integrally forged pressure components;
16. Cryogenic vessels (below -50 f);
17. Dimpled, embossed, jacketed, and non-metallic vessels and assemblies;
18. NDE requirements for acoustic emission, eddy current, and motion radiography;
19. ASME Sections UF, UB, UNF, UHA, UCI, UCL, UCD, UHT, ULW, ULT, UHX and UIG;
20. Code Cases and interpretations;
21. Requirements for pressure vessels for human occupancy; and
22. Rules for natural resource vessels, API-510, Section 9.