Understanding API ICP653 Reading 11-Worksheet-7

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Readings on APIICP650Reading 11 - Q&A PracticesMy Pre-exam Self Study Notes

13 th March 2016

harlie Chong/ Fion Zhang




Petroleum Upstream




Petroleum Upstream




Petroleum Upstream



API 653 Exam Administration -- PubEffectivity Sheet FOR: November 202016 and July 2016Listed below are the effective editions of the publications exam for the date(s) shown above. API Recommended Practice 571, Damage Mechanisms Affectingthe Refining Industry, Second Edition, April 2011




ATTENTION: Only the following sections / mechanisms fincluded on the exam:

1. Section 3, Definitions

2. Par. 4.2.7 Brittle Fracture3. 4.2.16 Mechanical Fatigue4. 4.3.2 Atmospheric Corrosion5. 4.3.3 Corrosion Under insulation (CUI)6. 4.3.8 Microbiologically Induced Corrosion (MIC)7. 4.3.9 Soil Corrosion8. 4.3.10 Caustic Corrosion

9. 4.5.1 Chloride Stress Corrosion Cracking (Cl-SCC)10. 4.5.3 Caustic Stress Corrosion Cracking (Caustic Embrittlem11. 5.1.1.10 Sour Water Corrosion (Acidic)12. 5.1.1.11 Sulfuric Acid Corrosion





API Recommended Practice 575, Inspection of AtmosPressure Storage Tanks, Third Edition, April 2014

API Recommended Practice 577 – Welding InspectionSecond Edition, December 2013

API Standard 650, Welded Tanks for Oil Storage, Twe2013 with Addendum 1 (September 2014), Errata 1 (JErrata 2 (December 2014).

API Recommended Practice 651, Cathodic Protection Petroleum Storage Tanks, Fourth Edition, September

API Recommended Practice 652, Lining of AbovegrouStorage Tank Bottoms, Fourth Edition, September 20 API Standard 653, Tank Inspection, Repair, Alteration

Reconstruction, Fifth Edition, November 2014.




American Society of Mechanical Engineers (ASME), B Vessel Code, 2013 Editioni. ASME Section V, Nondestructive Examination, A

23 (section SE-797 only)

ii. Section IX, Welding and Brazing Qualifications (W

See end of this study note for API Official BOK



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The Magical Book of Tank Inspection ICP






闭门练功




Fion Zhang at X

13th March 2016





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Q&A Practice 1Thanks George for your good works




Nice Job Geo




Super Memory – MemoirMARCH 2014 COMPUTER MEMORIES … We’ll call him

HARRISON … He remembered an amazing 105 Qs of 15

computerized exam and claims Control F function was noyou locate the Code Sections and REFERENCES ON AL

THIS MAKES FUN PRACTICE … … Nice Job George










Q1: Zn/ Cd detrimental to SS steel, possible liquid metal e

Q2: Patch plate at critical zone for service temperature >2>100⁰F for SS

Q3: Critical zone repair requirements




Q4: CaSi insulation material contains Cl-

Q5: Act of penetrating a thin component

Q6: Characteristics of SAW




Calcium Silicate Insulation Boards




Q7: Welder marking on work piece

Q8: Hot tap limitation on membrane stress

Q9: Tank bottom edge settlement (both condition must be




Q10: Definition of Repair

Q11: Definition of Critical Zone (3” is key point)

Q12: Colum wear plate (key point thickness of plate and f




Q13: Floating roof seal fastening material shall be austen

Q14/Q15: Hot tapping limitation

Q16: Gasket requirements

API Std 620

Design and Construction of Large, Welded,

Low-Pressure Storage Tanks, Twelfth Edition




Q18/Q19: UNKNOWN MATERIAL YIELD STRENGTH –

Q20: if you want to use A-283 instead of A-36 require pur

approval .

SEE also 4.1.5 Rules for SUBSTITUTION OF PLATE

Q21: Routine inspection interval – one month

https://la




Q22: Personnel for routine inspection

Q23: If the internal inspection is only for tank bottom




Robotic




Q24: Roof’s suitability for service

Q25: Appendix M for service temperature >200⁰F

Q26: Impressed Current & Galvanic systems pro & con.




Q27: Impressed Current & Galvanic systems pro & con.

Q28: Foundation Drip Ring Dimension (key word: 3”)

Q29: Dimension “C” (greater of 3” or 5t)

API653: Figure 9.1—Acceptable Details for Replacement

Material




5.4 Bottom Plates

5.4.1 All bottom plates shall have a corrod

less than 6 mm (0.236 in.) [49.8 kg/m2 (9

4.2.1.2)]. Unless otherwise agreed to by t

rectangular and sketch plates (bottom plashell rests that have one end rectangular)

nominal width of not less than 1800 mm (

5.4.2 Bottom plates of sufficient size shall

when trimmed, at least a 50 mm (2 in.) wi

outside the shell or meet requirements givwhichever is greater.

5.4.3 Bottom plates shall be welded in ac

5.1.5.4 or 5.1.5.5.

5.4.4 Unless otherwise specified on the Data Sheet, Line

requiring sloping shall have a minimum slope of 1:120 upw

of the tank.






Figure 5.5—Drip Ring (Suggested Deta

3 in.min

3 in.min3in.min

2

http://www.




Q30: Painting & Coating Inspector qualification requireme

Q31: Major causes of bad lining (Application & Curing fac




Q32: CP protection criteris: -850mV w.r.t saturated CSE

Q33: Concentration cell corrosion results in pitting corrosi




Q34: Lining suitable for service temperature (obsolete que




Q35: Thin film lining usually for new tank

Q36: LV Holiday testing (keyword: NACE RP0188/ testing




Q37: Number of tank settlement reading- Perimeter & eve

Q38: Differential aeration corrosion due to hard rock & di




Q39: Change in service (temperature or specific gravity) a

hydrotesting

Q40: MIC appearance – open book

Q41: MPI Equipment calibration – open book




Q41: Sulfuric acid percentage -85 and Temp -125 F – 50m




Q42: Magnetizing equipment calibration- Annually, lifting




Q43: Thickness is .50” Hole Type Source side




Q44/Q45: Densitometer calibration accuracy ±0.05 Dens

Q46: different plate thicknesses transition with 1:4 for Δt .




Q47: Tank Door sheet welding

Q48: Hierarchy of document




API653: 12.2 Radiographs

12.2.1 Number and Location of Radiographs

(for doorsheet welding?)

12.2.1.6 New and replaced shell plate and door sheet wel

radiographed. All junctions between repair and existing wradiographed. If defects are found, 100 % radiography sha

the repaired weld.

12.2.1.6.1 For circular replacement plates, a minimum

shall be taken regardless of thickness. When the circu

plate is located in a shell plate with thickness exceedishall be fully

radiographed.

12.2.1.6.2 For square and rectangular replacement pl

radiograph shall be taken in a vertical joint, and at lea

horizontal joint, and one in each corner. When the squ

replacement plate is located in a shell plate with thickthe vertical joints shall be fully radiographed.




Q49: acceptance limit for pit & welding at bottom plate crit

9.10.1.2 Repairs within the Critical Zone

The use of welded-on patch plates is permitted for repairing a portion of

critical zone (see 3.10 for definition) provided 9.10.1.1 requirements and

requirements are met.

…………………..

9.10.1.2.1 No welding or weld overlays (on the bottom plate) are permitt

except for the welding of: widely scattered pits (see 4.3.2.2), pinholes, c

plates, the shell-to-bottom weld, welded-on patch plates, or where the b

shell is being replaced.




Q50: Arc-gouging



Charlie Chong/ Fion Zhang

Arc Gouged




Arc Gouged




Pipeline Repair Welding- Arc Gouging




Q51: Lamination check for adding reinforcement plate

Q52: Proposed nozzle location- 4 UT points




Q53: NDE Examiner qualification

Q54: Disqualifications of bottom scanning examiners




Q55: Foundation settlement/ Uplift (tank over pressure)

Q56:

Q57, Maximum UT inspection interval

A , 5 YRS B, 15 YRS C, Half of Remaining Life (R.L) D,Remaining Life (R.L)




Q58: Banding & Peaking (New & inservice tank has differ

criteria)

Q59: Calcining of concrete due to high temperature and c

absorb water, swell and break.




Q60: Shielding gas used in welding, workers can become

exposure to modified atmospheres

Q61: Plate of unknown origin tested to A6/ A370




ASTM A6 - 14 Standard Specification for General Require

Structural Steel Bars, Plates, Shapes, and Sheet Piling , b

requirements, plates

ASTM A370 - 15 Standard Test Methods and Definitions Testing of Steel Products






Q64: Design temperature: LODMT of LA (design used LO




LA: 20⁰F, Minimum design metal tem[erature used 20+15API650: 3.6 design metal temperature

The lowest temperature considered in the design, w

or special local conditions justify another assumptio

be 8 °C (15 °F) above the lowest one-day mean am

locality where the tank is to be installed. Isothermal

mean temperature are shown in Figure 4.2. The tem

related to refrigerated-tank temperatures (see 1.1.1




Colorado (Denver) : -15⁰F, Minimum design metal used -API650: 3.6 design metal temperature

The lowest temperature considered in the design, w

or special local conditions justify another assumptio

be 8 °C (15 °F) above the lowest one-day mean am

locality where the tank is to be installed. Isothermal

mean temperature are shown in Figure 4.2. The tem

related to refrigerated-tank temperatures (see 1.1.1






Remembering John Denver




Q65: In-service bottom plate minimum thickness.

Q66: Internal inspection interval




Q67: Internal inspection interval

Q68: Maximum initial internal inspection interval

Q69: 10+5+2 =17




Q70: J value – open book t =.5”, toughness does not mee

Answer: J = 3”

9.9 Alteration of Existing Shell Penetrations

9.9.1 Existing shell penetrations may be altered if the altewith the requirements of API 650, Section 5.7 including th

minimum reinforcing area and the requirements for spacin

connections.

9.9.4 A new bottom may be installed through an existing t

reinforcing plate, provided all weld spacing and reinforcemas specified in API 650, are met. One of the following met

a) Remove only that portion of the existing reinforcing plat

and test the new bottom-to-shell weld. The lower edge of

shall be cut reasonably straight and horizontal and bevele

welding. See Figure 9.10 for weld joint details.




Figure 9.10—Details for Installing a New Bottom Throu

Tombstone Reinforcing Plate




b) Bevel the shell from the inside to allow for a full penetr

the bottom and shell. This method shall only be used o

annular plate or bottom sketch plate thickness is equal

10 mm (3/8 in.). This weld detail shall be used along th

reinforcing plate and shall extend a minimum of 25 mmedges of the reinforcing plate. Once beyond the reinfor

penetration weld shall tie in to the outside shell-to-botto

create a “water stop” and then transition to the typical s

detail. See Figure 9.11 for weld joint details.









c) The bottom portion of the reinforcing plate may be rem

horizontal cut between the bottom invert of the nozzle

bottom per requirements of Figure 9.12. The removed

plate shall be prepared for a full fusion splice weld with

(see Figure 9.12). The removed (or new) reinforcing plinstalled after the shell-to-bottom weld has been comp

and tested. The splice weld shall be made prior to the

weld to bottom plate weld. The completed splice weld s

particle examined.














API653: 3.20 major alteration/or major repair

An alteration or repair that includes any of the following:

a) installing a shell penetration larger than NPS 12 bene

level;

b) installing a bottom penetration within 12 in. of the shellc) removing and replacing or adding a shell plate beneath

level where the longest dimension of the replacement

d) removing or replacing annular plate ring material where

dimension of the replacement plate exceeds 12 in.;

e) complete or partial (more than one-half of the weld thicreplacement of more than 12 in. Of vertical weld joining

radial weld joining the annular plate ring;

f) installing a new bottom;

NOTE Installation of a portion of a new bottom as desc

not defined as a major repair.

g) removing and replacing part of the weld attaching the sor to the annular plate ring, in excess of the amounts li

h) jacking a tank shell.




Key word: Greater than 12”




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Q76: Fill height as determined by actual thickness

Q77:

Q78:

Q79:




API653: 4.3.2 Actual Thickness Determination

4.3.2.1

e) The criteria for continued operation is as follows:

I. the value t1 shall be greater than or equal to tmin (s

subject to verification of all other loadings listed inII. the value t2 shall be greater than or equal to 60 %

III. any corrosion allowance required for service until

inspection shall be added to tmin and 60 % of tmin.

4.3.2.2 Widely scattered pits may be ignored provided thaa) no pit depth results in the remaining shell thickness be

half the minimum acceptable tank shell thickness exc

corrosion allowance; and

b) the sum of their dimensions along any vertical line do

in an 8-in. length (see Figure 4.2).




Discussionshell plate thickness:

t1 = average thickness

The average plate thickness as determine using L=3.7

t2 = the minimum thickness

The minimum or least thickness as determined when in

corroded area. The t2 shall be ≥0.6tmin

tmin = the design minimum shell thicknessThe tmin = 2.6(H-1)DG/SE for whole course thickness c

Pitmaximum = the pitting on a shell plate shall not result in

<0.5tmin excluding corrosion allowance.




Q80: φ ray density ≥2.0 H&D X ray ≥1.8 H&D

Q81: Lighter “B” reject




9.8.4 Radioactive Source Selection

For weld inspection, typically radioactive isotopes of Iridiu

192 or Cobalt 60 are used. X-ray machines may also be u

Iridium 192 is normally used for performing radiographthickness range of 0.25 in. – 3.0 in. (6.3 mm – 76.2 mm

Cobalt 60 is used for steel thickness of 1.5 in. – 7.0 in.

The minimum or maximum thickness that can be radiogra

material is determined by demonstrating that the requiredobtained.






Q82: VT

Q83: Primary reason for PWHT




Q84: Filling Rates for thickness (.5”)

Q85: W.P.S question joint sketch given but did not mentio

Q86: P.Q.R question – thickness range qualification .




Q87: P.Q.R question - SA 516 Gr 70 – Mechanical and be

Q88: Critical length calculation – Given tank dia, least thic

thickness, remaining thickness and ask us calculate critica

Q89: T minimum for bottom shell

Q90: Remaining life calculation

Q91: Given corrosion rates for shell and bottom plates . aUT inspection interval .

Q92: Given different data for calculation height (H).




QW-150 TENSION TESTS

QW-153 Acceptance Criteria — Tension TestsQW-153.1 Tensile Strength. Minimum values for procedure qualificatio

column heading “Minimum Specified Tensile, ksi” of table QW/QB-4

tension test, the specimen shall have a tensile strength that is not le(a) the minimum specified tensile strength of the base metal; or

(b) the minimum specified tensile strength of the weaker of the two, if ba

minimum tensile strengths are used; or

(c) the minimum specified tensile strength of the weld metal when the a

provides for the use of weld metal having lower room temperature st

metal;

(d) if the specimen breaks in the base metal outside of the weld or weldbe accepted as meeting the requirements, provided the strength is n

the minimum specified tensile strength of the base metal.

(e) the specified minimum tensile strength is for full thickness specimen

Aluminum Al clad materials (P-No. 21 through P-No. 23) less than 1 ⁄ Aluminum Al clad materials 1 ⁄ 2 in. (13 mm) and greater, the specifie

strength is for both full thickness specimens that include cladding an

the core.




QW-160 GUIDED-BEND TESTS

QW-163 Acceptance Criteria — Bend Tests

The weld and heat-affected zone of a transverse weld ben

be completely within the bent portion of the specimen afte

guided-bend specimens shall have no open discontinuity ffected zone exceeding 1 ⁄ 8 in. (3 mm), measured in any d

convex surface of the specimen after bending. Open disco

on the corners of the specimen during testing shall not be

there is definite evidence that they result from lack of fusio

or other internal discontinuities. For corrosion-resistant wno open discontinuity exceeding 1 ⁄ 16 in. (1.5 mm), measu

shall be permitted in the cladding, and no open discontinu

(3 mm) shall be permitted along the approximate weld inte




QW-170 NOTCH-TOUGHNESS TESTS

QW-171.2 Acceptance. The acceptance criteria shall be

that Section specifying impact requirements.

QW-190 OTHER TESTS AND EXAMINATIONSQW-191 Volumetric NDE

QW-191.1 Radiographic Examination

QW-191.1.2 Acceptance Criteria

QW-191.2 Ultrasonic ExaminationQW-191.2.3 Acceptance Criteria for Qualification

Test Welds.




Q92: Welder symbol is not required for which type of joint

CHAPTER 11 API 653 … easy … see question and refere

Q93: Given shell and bottom plate corrosion rate and ask

interval Since we know corrosion rate, calculate the corronot known the interval is 5 years

b) When the corrosion rate is known, the maximum interva

smaller of RCA/2N years (where RCA is the difference be

measured shell thickness and the minimum required thickis the shell corrosion rate in mils per year) or 15 years.

Q94: Meaning of RCA




Q95: Keyword in the exam is experiences with coatings a

BOOK




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Q96: Key word is to the maximum liquid level , not shell h

examination they mentioned tank height and liquid level a

one we have to consider for calculating thickness




Q97: Earthing ≤25Ω approximately

Q98: Internal corrosion of tank vapor space by (1) H2S (2)

combination of above.




Q98B: Carbon Steel (Unknown Specification) – thickness

20⁰F- safe for use




Q99: Need for Hydrotest .




Q100: New material

Q101: Thickness calculation and material allowable stress




Q102: The AI designate inspection hold point

Q103: Minimum dimension of replacement shell plate is 1is greater.




API653: 9.1.3 All repair work must be authorized by the a

or an engineer experienced in storage tank design, before

the work by a repair organization.

Authorization for alterations to storage tanks that comply wnot be given without prior consultation with, and approved

experienced in storage tank design.

The authorized inspector will designate inspection hold po

the repair or alteration sequence and minimum documentsubmitted upon job completion.

The authorized inspector may give prior general authoriza

routine repairs as long as the authorized inspector is sure

not require hydrostatic testing or do not require an engine




9.2.2 Minimum Dimensions of Replacement Shell Plat

9.2.2.1 The minimum dimension for a replacement shell p

times the thickness of the replacement plate, whichever is

replacement plate may be circular, oblong, square with ro

rectangular with rounded corners except when an entire sreplaced. See Figure 9.1 for typical details of acceptable r

plates.




Q104:

Q105:

Q106:




API650:

5.6 Shell Design

5.6.1 General

5.6.1.2 Unless otherwise agreed to by the Purchaser, the

have a minimum nominal width of 1800 mm (72 in.). Platewelded shall be properly squared.

API653:

9.2 Removal and Replacement of Shell Plate Material

9.2.2 Minimum Dimensions of Replacement Shell Plat

9.2.2.1 The minimum dimension for a replacement shell p

times the thickness of the replacement plate, whichever is

replacement plate may be circular, oblong, square with ro

rectangular with rounded corners except when an entire s

replaced. See Figure 9.1 for typical details of acceptable r

plates.




API653

9.3 Shell Repairs Using Lap-welded Patch Plates

9.3.1.7 The maximum vertical and horizontal dimension o

48 in. and 72 in., respectively. The minimum repair plate d

The repair plate shall be formed to the shell radius.




DiscussionType of repair plate

1. New plate

Minimum dimension: 72” width2. Replacement plate

Minimum dimension 12” or 12t whichever greater

3. Patch welded plate

Maximum dimension 48” vertical x 72” horizontal, minim




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Q&A Practice 2 API 653 PREPARATORY

IMPORTANT CLOSED BOOK QUES






My Self Study NotesQQ自学群: API超级检验师 47610017


API 653 PREPARATORY

IMPORTANT CLOSED BOOK QUESTIONSA

No. QUESTION C

1 Definition of the Critical zone

3.10 critical zoneThe portion of the tank bottom or annular plate within 3 in. of the inside edge of the shell, measured radial

2 Definition of Change of Service A

3.7 change in service A change from previous operating conditions involving different properties of the stored product such as sdifferent service conditions of temperature and/or pressure.

3. Minimum thickness of corroded roof plate A4.2.1.2 Roof plates corroded to an average thickness of less than 0.09 in. in any 100 in.2 area or roof plateplate shall be repaired or replaced.

4. Limits of L A

L = 3.7√(Dt2), but not more than 40 in.

5. Definition of widely scattered pits A4.3.2.2 Widely scattered pits may be ignored provided that:a) no pit depth results in the remaining shell thickness being less than one-half the minimum acceptable

the corrosion allowance; andb) the sum of their dimensions along any vertical line does not exceed 2 in. in an 8-in. length (see Figure





6. Causes for shell distortion A

4.3.5 Distortions

4.3.5.1 Shell distortions include out-of-roundness, buckled areas, flat spots, and peaking joints.4.3.5.2 Shell distortions can be caused by many conditions such as foundation settlemenhigh wind, poor shell fabrication, or repair techniques, and so forth.4.3.5.3 Shell distortions shall be evaluated on an individual basis to determine if specific acceptable for continuing tank service and/or the extent of corrective action.

7. Cracks in the shall to bottom weld – what should be done A4.3.6 FlawsFlaws such as cracks or laminations shall be thoroughly examined and evaluated to deteand need for repair. If a repair is needed, a repair procedure shall be developed and impfor repairing scars such as arc strikes, gouges, or tears from temporary attachment weldcase-by-case basis. Cracks in the shell-to-bottom weld shall be removed.

Comments:Crack- No, NoOthers- must be evaluated on a case by case basis

8. What is the reason for the distortion of anchor bolts & excessive cracking of

concrete structures

A

4.5.3 Anchor Bolts

Distortion of anchor bolts and excessive cracking of the concrete structures in which theyindications of either serious foundation settlement or a tank overpressure uplift condition





9. Tanks fabricated from steels of unknown toughness, thickness less than ½” can

be operated at above what minimum shell metal temperature

A

5.3.5 Step 4—If a tank shell thickness is no greater than 0.5 in., the risk of failure due to provided that an evaluation for suitability of service in accordance with Section 4 has beenominal thickness for the thickest tank shell plate shall be used for this assessment.5.3.6 Step 5—No known tank failures due to brittle fracture have occurred at shell metal above. Similar assurance against brittle fracture can be gained by increasing the metal tetank contents.5.3.7 Step 6—Industry experience and laboratory tests have shown that a membrane strleast 7 ksi is required to cause failure due to brittle fracture.

10. Interval for routine In-service inspection A6.3.1 Routine In-service Inspections6.3.1.1 The external condition of the tank shall be monitored by close visual inspection frbasis. This inspection may be done by owner/operator personnel, and can be done by otinspectors as defined in 3.4. Personnel performing this inspection should be knowledgeaoperations, the tank, and the characteristics of the product stored.6.3.1.2 The interval of such inspections shall be consistent with conditions at the particulone month.

11. Who shall carry out External Inspection A6.3.2 External Inspection6.3.2.1 All tanks shall be given a visual external inspection by an authorized inspector. Tthe external inspection and must be conducted at least every five years or RCA/4 N yearsbetween the measured shell thickness and the minimum required thickness in mils, and in mils per year) whichever is less. Tanks may be in operation during this inspection.

12. Interval for External inspection A As above







4.4.1 GeneralTank bottom inspection strategies shall provide suitable data which, when used with the

will determine the tank bottom integrity necessary to prevent leakage of fluids that may cEach aspect of corrosion phenomena, and other potential leak or failure mechanism mus

Periodic assessment of tank bottom integrity shall be performed in addition to the internaThe assessment period shall be less than or equal to the appropriate internal inspection use of leak detection tests or monitoring systems (such as double bottoms or liners undedetection pipes) will satisfy the requirement for periodic assessment between internal ins

Excessive foundation settlement of storage tanks can affect the integrity of tank shells anmonitoring the settlement behavior of tanks is a recognized practice to assess the integr

Annex B for techniques for evaluating tank bottom settlement.

17. alternative Internal Inspec tion method A6.4.2.1.2 As an alternative to establishing the initial interval in accordance with Section 6initial internal inspection date and reassessment can be established using Risk Based Inper 6.4.2.2.2.These assessments may establish an initial inspection interval exceeding 10 years but stanks without a Release Prevention Barrier, or 30 years for tanks with a Release Preven

18. What is the bottom plate minimum thickness A

a) 0.10” Tank bottom/foundation design with no means for detection and containment of

b) 0.05” Tank bottom/foundation design with means to provide detection and containme

c) 0.05” Applied tank bottom reinforced lining, > 0.05 in. thick, in accordance with API 6





19. Construction records shall include the following information A

6.8.2 Construct ion Records

Construction records may include nameplate information, drawings, specifications, constand any results of material tests and analyses.

20. New material for tank reconstruction shall comply to which standard A7.2 New Materials

All new materials used for repair, alterations, or reconstruction shall conform to the curre

21. Welding consumables shall conform to which spec ification A

7.4 Welding ConsumablesWelding consumables shall conform to the AWS classification that is applica

22. What are the minimum dimensions for a replacement shell A9.2.2 Minimum Dimensions of Replacement Shell Plate9.2.2.1 The minimum dimension for a replacement shell plate is 12 in. or 12 times the thplate, whichever is greater. The replacement plate may be circular, oblong, square with rrectangular with rounded corners except when an entire shell plate is replaced. See Figuacceptable replacement shell plates.

23. The corners of a repair plate shall be rounded to what minimum radius A

9.3.1.4 The shape of the repair plate may be circular, oblong, square, or rectangular. All to bottom joint, shall be rounded to a minimum radius of 2 in. The nozzle reinforcing plate5-8, are also acceptable.







29. The maximum allowed undercutting for horizontal joints of a reconstructed

tank is

A

API653: 10.4.2.5 The edges of all welds shall merge with the surface of the plate withoutpermissible weld undercut shall be in accordance with API 650, Section 7.2.1.4 and Sec

API650: 8.5.2 A weld shall be acceptable by visual examination if the inspection shows ta) There are no crater cracks, other surface cracks or arc strikes in or adjacent to the wb) Maximum permissible undercut is 0.4 mm (1/64 in.) in depth for vertical butt joints, ve

attachments, attachment welds for nozzles, manholes, flush-type openings, and the iFor horizontal butt joints, horizontally oriented permanent attachments, and annular-rpermissible undercut is 0.8 mm (1/32 in.) in depth.

c)

30. If the material spec ification for the steel from an existing tank is unknown or

obsolete, how do you qualify the welding procedure

A

11.1.2 Weldability of steel from existing tanks shall be verified. If the material specificatioexisting tank is unknown or obsolete, test coupons for the welding procedure qualificatioactual plate to be used.

31. At what intervals Welders identification shall be marked adj. to welds A11.2.2 The welder or welding operator’s identification mark shall be hand- or machine-staintervals not exceeding 3 ft along the completed welds. In lieu of stamping, a record maywelder or welding operator employed for each welded joint; these records shall be accesplate welds and flange-to-nozzle-neck welds do not require welder identification.





32. What alternative methods are used to inspec t the integrity of the welded

bottom joint

A

API653: 12.1.7 Bottoms12.1.7.1 Upon completion of welding on a tank bottom, the plates and the entire length oplates shall be examined visually for any potential defects and leaks. Particular attention sumps, dents, gouges, three-plate laps, bottom plate breakdowns, arc strikes, temporaryand welding lead arc burns. Visual examination acceptance and repair criteria are specifIn addition, all new welds, including the weld attaching a patch plate to the bottom, the aby welding, and the restoration of welds found with defects during an internal inspection the methods specified in API 650, Section 7.3.3. Leaking areas shall be repaired by grindrequired, and the repaired area shall be retested.

API650: 7.3.3 Examination and Testing of the Tank Bottom

Upon completion of welding of the tank bottom, the bottom welds and plates shall be exapotential defects and leaks. Particular attention shall apply to areas such as sumps, dentbottom plate breakdowns, arc strikes, temporary attachment removal areas, and weldingexamination acceptance and repair criteria are specified in 8.5.

In addition, all welds shall be tested by one of the following methods.

a) A vacuum-box test in accordance with 8.6.b) A tracer gas test in accordance with 8.6.11.c) After at least the lowest shell course has been attached to the bottom, water (to be sushall be pumped underneath the bottom. A head of 150 mm (6 in.) of liquid shall be main

dam to hold that depth around the edge of the bottom. The line containing water for testitemporarily by running it through a manhole to one or more temporary flange connectionthe line may be installed permanently in the subgrade beneath the tank. The method of igoverned by the nature of the subgrade. Reasonable care shall be taken to preserve thethe tank.





33. Areas of bottom plate repaired by welding in addition to MT/PT are any other

testing done.

A

12.1.7.3 In addition to the requirements in 12.1.7.1, areas of bottom plate repaired by wethe magnetic particle method or the liquid penetrant method. In addition, the repaired area vacuum box and solution or a tracer gas and detector.

34. The minimum diagnostic length of each radiograph is A12.2.1.7 The minimum diagnostic length of each radiograph shall be 6 in.

35. For penetration installed using insert plates , butt weld between the insert

plate & shell plate shall be radiographed to what extent

A

12.2.1.8 For penetrations installed using insert plates as described in 9.8.6, the complete

insert plate and the shell plate shall be fully radiographed.

36. Hydrostatic test of a reconstructed tank shall be held for how long time. A12.3.1 When Hydrostatic Testing is Required

A full hydrostatic test, held for 24 hours, shall be performed on the following.a) A reconstructed tank.b) Any tank that has undergone major repairs or major alterations (see Section 3) unlessapplicable combination of materials, design, and construction features.c) A tank where an engineering evaluation indicates the need for the hydrostatic test dueseverity of service. Examples of increased service severity are an increase in operating pproduct with a higher specific gravity), lowering the service temperature (see Figure 5.2)

been damaged.







12.5.1 When Settlement Survey is Required A settlement survey shall be conducted for all existing tanks that undergo a hydrostatic t

have a documented service history of acceptable settlement values, and no settlement ithe hydrotest.

12.5.2 Initial Settlement SurveyWhen a settlement survey is required in accordance with 12.5.1, the tank settlement shathe tank empty, using an even number of elevation measurement points, N , uniformly discircumference. An initial settlement survey, prior to the first hydrostatic test, provides bassettlement evaluation. In the absence of this initial survey, the tank shall be assumed to

The minimum number of elevation points shall be as indicated by the following equation: N = D/ 10

where D is the tank diameter, in feet (ft). N is the minimum required number of settlement measurement points, but no less than erounded to the next higher even whole number. The maximum spacing between settlembe 32 ft.

39. Internal Bottom settlement formula AB.3.3 Internal Bottom Settlements or BulgesMeasure the bulge or depression. The permissible bulge or depression is given by the foBB = 0.37R

whereBB is maximum height of bulge or depth of local depression, in inches;R is radius of inscribed circle in bulged area or local depression, in feet.





40. What is the NDT Inspector Qualification requirement for carrying out UT during

tank repair?

A

API650: U.4 Personnel Qualif ications and Training U.4.1 Personnel Qualif ications—evaluating UT examinations shall be qualified and certified in accordance with their emplSNT-TC-IA or CP-189 shall be used as a guideline. Only Level-II or Level-III personnel sexaminations, analyze the data, or interpret the results.

41 UT procedure shall follow which Code/Standard A Annex T (informative) NDE Requirements Summary

Definitions: MT =Magnetic Particle Examination Pen Oil =Penetrating Oil Test PT =Liquid Penetrant Examination RT=Radiographic Testing VB =Vacuum-Box Testing VE =Visual Examination

Acceptance Standards: MT: ASME Section VIII, Appendix 6 (Paragraphs 6-3, 6-4, 6-5) PT: ASME Section VIII, Appendix 8, (Paragraphs 8-3, 8-4, 8-5) RT: ASME Section VIII, Paragraph UW-51(b) Tracer Gas: API Std 650, Section 8.6.11.b UT: For welds examined by UT in lieu of RT, acceptance standards are in Annex U.6

for the requirements of 7.3.2.1, the acceptance standard is as agreed upon by the M VB: API Std 650, Section 8.6.9 VE: API Std 650, Section 8.5.2





Examiner Qualifications: MT:API Std 650, Section 8.2.3

PT:API Std 650, Section 8.4.3 RT:ASNT SNT-TC-1A Level II or III. Level-I personnel may be used under the superv

with a written procedure in accordance with ASME Section V, Article 2. Tracer Gas: None UT:For welds examined by UT in lieu of RT, the inspector must be ASNT-TC-1A or C

per API Std 650 Annex U.4.1. For UT when RT is used for the requirements of 7.3.2.1, t ASNT-TC-1A Level II or Level III. A Level I may be used with restrictions, see API St VE: API Std 650, Section 8.5.1 VB: API Std 650, Section 8.6.4

Procedure Requirements: MT: ASME Section V, Article 7 PT: ASME Section V, Article 6 RT: A procedure is not required. However, the examination method must comply wit Acceptance standards shall be in accordance with ASME Section VIII, Paragraph UW UT: For shell welds examined by UT in lieu of RT, ASME, Section V, Article 4 and AP

welds when RT is used for the requirements of 7.3.2.1, ASME Section V. VB: API Std 650, Sections 8.6.2, 8.6.5, 8.6.6, 8.6.7, and 8.6.8 VE: None Tracer Gas: API Std 650, Section 8.6.11.a




Q&A Practice 3 API 653 PREPARATORY

IMPORTANT OPEN BOOK QUESTIO






My Self Study NotesQQ自群: API超级检验 47610017


API 653 PREPARATORYIMPORTANT OPEN BOOK QUESTIONS

No. QUESTION

1 Calculate the t min. welded tank shell

a) When determining the minimum acceptable thickness for an entire shell course, t min is calculated as foll

b) When determining the minimum acceptable thickness for any other portions of a shell course (such as alocation of interest), t min is calculated as follows:

Where:t min is the minimum acceptable thickness, in inches for each course as calculated from the above equation;

however,t min

shall not be less than 0.1 in. for any tank course; D is the nominal diameter of tank, in feet (ft); H is the height from the bottom of the shell course under consideration to the maximum liquid level whenevaluating an entire shell course, in feet (ft); oris the height from the bottom of the length L (see 4.3.2.1) from the lowest point of the bottom of L of thelocally thinned area to the maximum liquid level, in feet (ft); oris the height from the lowest point within any location of interest to the maximum liquid level, in feet (ft);G is the highest specific gravity of the contents;





S is the maximum allowable stress in pound force per square inch (lbf/in.2); use the smaller of 0.80Y or 0.4use the smaller of 0.88Y or 0.472T for all other courses. Allowable shell stresses are shown Table 4.1 for mprevious editions of API 12C and API 650;

NOTE for reconstructed tanks, S shall be in accordance with the current applicable standard;Y is the specified minimum yield strength of the plate; use 30,000 lbf/in.2 if not known;T is the smaller of the specified minimum tensile strength of the plate or 80,000 lbf/in.2; use 55,000 lbf/in.2 E is the original joint efficiency for the tank. Use Table 4.2 if original E is unknown. E = 1.0 when evalucorroded plate, when away from welds or joints by at least the greater of 1 in. or twice the plate thickness.

2 What is the maximum allowable stress for bottom & second course

3. To change the service of the tank to above 200°F what requirements are to be met 4.2.4.3 Operation at Elevated Temperature

All requirements of API 650, Annex M, shall be considered before changing the service of a tank to operat





4. What is the maximum allowable stress for reconstructed tank

NOTE 6 The allowable stresses for reconstructed tanks are tabulated in API 650, Table 58.4 of this standard.

5. What is the maximum allowable stress for revited tank

4.3.4.1 The minimum acceptable thickness for riveted tank shells shall be calculated usinexcept that the following allowable stress criteria and joint efficiencies shall be used:S is 21,000 lbf/in.2;E is 1.0 for shell plate 6 in. or more away from rivets. See Table 4.3 for joint efficiencierivets.

6. Annular bottom plate thickness (Sp. Gr. < 1.0)

Table 4.5—Annular Bottom Plate Thicknesses (in.) (Product Specific Gravity < 1.0)







9. What are the material specifications for structural materials

7.3 Original Materials for Reconstructed Tanks7.3.1 Shell and Bot tom Plates Welded to the Shell

7.3.1.1 All shell plate materials and bottom plates welded to the shell shall be identified. original contract drawings, API nameplates, or other suitable documentation do not requMaterial not identified shall be tested and identified by the requirements as outlined in 7.3determination shall be made as to suitability of the material for intended service.

7.3.1.2 Each individual plate for which adequate identification does not exist shall be suband mechanical tests as required in ASTM A6 and ASTM A370 including Charpy V-notchthe requirements of API 650, Section 4.2.9, Section 4.2.10, Section 4.2.11, and Table 4-4direction of rolling is not definitely known, two tension specimens shall be taken at right acorner of each plate, and one of those test specimens must meet the specification requir

7.3.1.3 For known materials, all shell plates and bottom plates welded to the shell shall mchemistry and mechanical properties of material specified for the application with regard metal temperature given in API 650, Figure 4-1a or Figure 4-1b.





10. Shell design for a rec onstructed tank, with materials whose allowable stresses are not giv

in Table 3-2 of API 650, what a llowable stresses are to be taken

8.4 Shell Design

8.4.1 Thickness to be used for each shell course when checking tank design shall be baswithin 180 days prior to relocation. (See 4.3.2 for measuring procedure, number, and locthicknesses.)8.4.2 The maximum design liquid level for product shall be determined by calculating thefor each shell course based on the specific gravity of the product, the actual thickness mcourse, the allowable stress for the material in each course, and the design method to be

The allowable stress for the material shall be determined using API 650, Table 5-2a or T

For material not listed in Table 5-2a or Table 5-2b, an allowable stress value of the lessetensile strength shall be used.

8.4.3 The maximum liquid level for hydrostatic test shall be determined by using the actueach shell course, the allowable stress for the material in each course, and the design m

The allowable stress for the material shall be determined using API 650, Table 5-2a or T

For material not listed in Table 5-2a or Table 5-2b, an allowable stress value of the lessetensile strength shall be used.





11. After the valve has been installed on the flange at what pressure the pressure test shall b

performed

9.14.5.3 After the reinforcing plate has been welded to the shell and NDE performed, the

tested by the procedure described in API 650, Section 7.3.4. After the valve has been inspressure test at least 1.5 times the hydrostatic head shall be performed on the nozzle prmachine, which shall be bolted to the valve. The required pressure for the pressure test computed by the following equation:

where H 2 is the height of tank shell in inches (in.);G is the specific gravity of product stored, as specified by purchaser. The specific gravity

γw is the density of water in pound force for cubic inch (lbf/in.3).

12. In tank reconstruction, new vertical joints in adjacent shell courses shall be offset by wha

minimum distance

10.4.2 Welding10.4.2.1 Provisions shall be made during the reconstruction of a tank to ensure that weldFigure 9.1 are maintained. New vertical joints in adjacent shell courses, made in accordabe aligned but shall be offset from each other a minimum distance of 5t , where t is the plcourse at the point of the offset.

13. During tank reconstruction / repair what is the maximum allowed undercutting for vertica

joints

10.4.2.5 The edges of all welds shall merge with the surface of the plate without a sharp weld undercut shall be in accordance with API 650, Section 7.2.1.4 and Section 8.5.1 b).





14. What is the maximum reinforcement allowed for horizontal joint of ¾” plate

Table 10.1—Maximum Thicknesses on New Welds





15. In completed horizontal butt joints, the upper plate shall not project beyond the lower p

by how much

10.4.4 Shells

10.4.4.1 Plates to be joined by butt welding shall be matched accurately and retained in Misalignment in completed vertical joints over 5/8-in. thick shall not exceed 10 % of the pmaximum of 1/8 in. Misalignment in joints 5/8-in. thick or less shall not exceed 1/16 in. Vcompleted before the lower horizontal weld is made.

10.4.4.2 In completed horizontal butt joints, the upper plate shall not project beyond the fpoint by more than 20 % of the thickness of the upper plate, with a maximum projection oprojection of 1/16 in. is acceptable for upper plates less than 5/16-in. thick.

10.4.4.3 For horizontal and vertical joints in tank shell courses constructed of material ovthe thickness of the thicker plate at the joint), multi-pass weld procedures are required, w

thick permitted. A minimum preheat of 200 °F is required of these welds.16. Calculation of Internal Bottom settlement or bulges

B.3.3 Internal Bottom Settlements or BulgesMeasure the bulge or depression. The permissible bulge or depression is given by the fo BB = 0.37 Rwhere BB is maximum height of bulge or depth of local depression, in inches; R is radius of inscribed circle in bulged area or local depression, in feet.Figure B.10 is a graphical representation of this equation.

17. Problem on edge settlement

Tanks with larger edge settlements are to be repaired, or have detailed analysis of bottoJunction Welds in tanks with settlement greater than or equal 75 % of Bew, and larger thwith magnetic particle or liquid penetrant methods





18. For welding A516 Gr 70 materials what electrode classification shall be used

7.2.1.11 Low-hydrogen electrodes shall be used for all manual metal-arc weld

courses, including the attachment of the first shell course to bottom or annular pl

a) Where the plates are thicker than 12.5 mm (1/2 in.) (based on the thickness of

joined) and made of material from Groups I–III.

b) For all thicknesses when the plates are made of material from Groups IV, IVA,




Reading4POINTS TO RECALL












1. API 653 is code used for inspection, repair, and altera

aboveground storage tanks which are placed in Serv

basic construction code for making New Tanks.

2. API 650 and API 653 are used for aboveground storaatmospheric pressure (maximum 2.5 psi above atmostemperatures not exceeding 90ºC. (200ºF)

3. Design metal temperature of tank is assumed to be 8º

lowest one day mean temperature of tank site.

4. Where necessary, as per Fig. 2-1 (API 650), the tank

checked against brittle failure by conducting impact te

criteria shall be as per Table 2-4.




Table 4.5b—Minimum Impact Test Requirements for P

(See Note)




5. If average value of 3 specimen is < specified average

reject.

But if average value of 3 specimen ≥ SAV and,

Value of one specimen is < SAV but ≥ 2/3 SAV — ac

Value of one specimen is < SAV and also < 2/3 SAV —

Value of two specimen is < SAV — retest

On retest for b and c all three specimen≥

SAV — acc




6. The required thickness of shell plates for tanks up to 6

diameter shall be greater of td or tt:

Where:D = Tank Diameter m (ft)

H = Height shell course from top liquid level in m (ft)

G = Specific Gravity of liquid to be stored

Sd / St = Allowable stress for design and hydrostatic condition

C.A. = Corrosion allowance in mm (in)






10. All nozzles, manholes and other openings shall have

thickness, reinforcement plates and weld sizes as per

of API 650.

11. Radiography inspection is required for all shell butt weplate butt welds and insert plates for manhole and noz

10. For shell plates the number of radiographs required d

the plate thickness is up to 10 mm (3/8), or above 10

– 1”) or above 25 mm (1”). (Fig. 6-1 of API 650).




13.Radiography is also required on: 100% length of butt w

plate to shell, and Annular bottom plate radial joints (1 spo

welds if double butt welded and 1 spot on 50% of radial wwith backing strip.)








According to API 653, “Repairs” means any work necessa

restore the safe operating conditions (as per original desig

means any work that changes the dimensions and/or conf(changing original safe operating conditions).

“ Authorized inspection agency” is any one of the follow API tank inspector):

An owner operator

Subcontractor to owner operator

Inspection organization of jurisdictionInspection organization of insurance company

“ Break-over point” means area of tank bottom where se

“ Change of service” means change in fluid stored and h

specific gravity or corrosivity or different temperature or pr




“ Critical zone” means portion of tank bottom within 3 inc

and measured radically inwards.

“ Repair organization” means any of the following who c

alterations according to API 653.• Owner-user

• Subcontractor to owner-user

• Subcontractor authorized or approved by jurisdiction

Tank roof plates which are so corroded that there are throaverage thickness is less than 0.09 inch in any 100 sq

plates must be repaired or replaced, i.e., tank cannot b

continue operation.




• If tank service is to be changed resulting in increase of

operation above 90º C (200º F), then requirements of

M must be fulfilled respectively. If service changes low

material must be suitable as per impact test requireme

Tank shell evaluation: 5 step method.

• Widely scattered pits can be ignored if:

1. No pit depth results in shell thickness being less th

thk – excluding C. A.

2. Sum of pit dimensions along any vertical line doesinches in a total length of 8”.




• Minimum thickness for bottom plates is given by:

• Anular plates (product sp. gr. < 1.0): Table 4-3 (AP

• (Product sp. gr. ≥ 1.0): Table 3-1 (API 650)

• Other bottom plates: Table 6-1 (API 653)

Min. thickness in “critical zone” is smaller of:(but not less t

Half of original bottom thickness in critical zone, and

Half of tmin for first shell course.

• Tanks designed prior to API 650 (7th edition, 1980) mabrittle failure as per Fig. 5.2.

• Tanks are not likely to fail in brittle failure if thickness i

or shell temperature is not less than 60º F or stress lev

7,000 psi.




Day 3




Inspection Frequency (External) shall not exceed followin

• Routine-in Service inspection every one month.

• External inspection (visual by authorized inspector): Loremaining life (RCA/4N) or 5 years.

• Ultrasonic thickness inspection (external) of shell.when corrosion rate is not known — maximum 5 years

when corrosion rate is known — lower of :

half remaining life (RCA/2N) or 15 years

Inspection Frequency (Internal) shall not exceed:• Based on MRT calculations, as per “Or” calculated but

years (25/30 yrs)

• If corrosion rates are not known: Actual bottom thickne

determined not later than 10 years. (could be inservice




• Alternative to point no. 2 above for internal inspection

altered based on RBI. The RBI basis shall be reviewed

exceeding 10 years by authorized inspector and tank e

• If there is access to tank bottom to determine bottom t

such inspection may be used in lieu of internal inspect

Inspection records include:

• Permanent Records (Tank construction data)

• Inspection history (Progressive Records)

• Repair/alteration history (Repair/alteration records)




New materials for repair/alteration/ reconstruction: All plat

shell and the bottom plates welded to shell shall be identif

Thickness of shell plates to be used for checking the tank

within 180 days before relocation.

The strength values Sd and St for reconstructed tank sha

allowable stress as per table 3-2 of API 650.

The replacement shell plate thickness≥

thickness of the sreplacement is proposed and dimensions and spacing sha

9-1.






All shell plate defects like the cracks, gauges, tears, widel

corroded areas shall be evaluated case by case as per ch

New reinforcements can be added to existing unreinforce

9-3a and 9-3b.

Repairs within critical zone of the bottom require additiona

“Tombstone” type patch and additional PT or MPI testing

examination of patch welds, and weld shall be made by m

If impact test was not done on original tank material, the h

limited to NPS 4 (max).

Toe-to-toe minimum spacing between hot tap and adjace√(RT)

where R= tank shell radius in inches T is shell plate thickn




Day 4




For tank relocation, the bottom, shell or roof may be cut in

existing tank so that the pieces are suitable for transporta

For dismantling the tank the bottom may be cut 12” away weld, if entire bottom plates are to be used.

Alternatively cut the bottom and shell at 1/2” from toe of sand discard the weld portion.

For rest of the bottom, de-seaming of welds or cutting 2” a

be done.

Shell plates ≤ ½” thk may be dismantled by cutting throug

removing HAZ. If shell plate thk > ½”, discard welds + HA Alternatively, shell plates may be cut 6” away from existin




NDT for Repair / Alteration:

PT / MT: For all fillet welds and fill-up (weld-build up) durin

alteration

Radiography:

New welds during repair or alteration between the plates sNew to new plates — same as API 650

New to old plates or old to old plates. Additional examinat

1 spot for each 50 feet for horizontal weld

1 spot on each vertical weld

1 radiograph on each T-jointRepair of old butt-welds — entire length of repair

A full hydrostatic test (held for 24 hours) is required on ma

major alterations which include:

Installation of nozzles larger than NPS 12 below liquid lev




Repair / Replacement of more than 12” length of vertical w

radial weld in anular plates

Any repair / replacement on shell to bottom weld

Jacking of tank shell

Exemption for hydrotest is possible only if owner / operatoengineer give the exemption in writing.

Hydrostatic test of reconstructed tank is compulsory.

Out of plumbness for reconstructed tank is 1/100 of the ta

maximum 5 inches.

For tank settlement survey, the number of elevation meastank diameter D ft. is given by: N=D/10, but minimum 8.

Permitted internal settlement (for bulge or depression) is g

B = 0.37 R

Where B = Max. height of bulge or depth of settlement (in

And R = Radius of largest inscribing circle (feet)




Based on Fig. B-10, and B-11 maximum allowable edge s

out depending on settled area being approximately paralle

to shell.

As per API RP 575, the grounding connection inspection s

external visual inspection. Total resistance from tank to soexceed approximately 25 ohms.

Ultrasonic thickness measurements as a minimum must b

one TML on each shell course. TMLs also shall be establ

uncoated portion of shell for floating roof tanks.

For internal inspection of tank bottoms, a preliminary randscanning survey is carried out in X pattern across the tank

circumference. If significant corrosion is detected, entire b

scanned.

For internal inspection of shell, the major areas of focus sspace, liquid-vapour interface and the bottom area.




Leak testing of shell may be done hydrostatically or by us

vacuum box test.

Leak testing of bottom may be done by:

Using vacuum box test

By construction of clay dam around tank and filling under (observe seepage inside)

Apply seal to tank outer perimeter and introduce compres

bottom, check welds by applying soap solution or by obse

filling inside of tank by water for 6” height

By injecting inert gas with tracer gas under the tank and uto detect leakage

Hammer test is never carried out on cast iron parts.

Corrosion rate curves are helpful as an important record o

of tank in past and anticipated remaining life in future.




Day 5




WPS gives parameters to be used in production job, and

ranges qualified by the PQR test.

Essential variables (EV), if changed require new procedur

essential variables (NEV) may be changed without new pqualification.

Bend test crack shall not exceed 1/8” in any direction for f

or side bend.

Supplementary essential variables (SEV) are considered

is impact strength requirement. Otherwise they are “non-e

Tensile test for procedure qualification is passed if failure

Weld metal at strength>= Base metal SMTS or

Base metal at strength>= 95% of base metal SMTS.




P-numbers represent parent metal groupings of similar co

properties, i.e., similar strength and ductility.

F-numbers give similar usability aspects of filler material.

A-numbers give similar chem. comp. In “As welded” cond

For performance, 1G is flat, 2G is horizontal, 3G is vertica

overhead position. Pipe 5G qualifies 1G, 3G and 4G,

but pipe 6G qualifies all positions.

Welders who have not welded for more than 6 months on

qualification will expire for that process.

In Galvanic corrosion, current flows from anode to cathod

will lose metal and cathode will gain. If we make the “comprotected” cathodic with respect to surrounding, it will not be protected.




As soil resistivity goes up, soil is less corrosive and vice-v

Soil resistivity < 500 ohm-cm is highly corrosive,

10,000 ohm-cm, is least corrosive.) Ref. Table 1-API 65

Cathodic protection methods: Galvanic and impressed cuGalvanic current: Easy to install, cheap, easy to maintain,(Not suitable for large structure)

Impressed current: Expensive, but more effective, suitable

Requires constant monitoring.

CP system survey intervals:

Impressed current:

Rectifier (power source) — Max. 2 months

Other components — Max. 1 year

Galvanic System (sacrificial anode system): Annually

CP survey records should be maintained normally for 5 ye






API651: 11.4.7

Records sufficient to demonstrate the need for corrosi

should be retained as long as the facility involved rema

Records related to the effectiveness of cathodic protecretained for a period of five years unless a shorter per

allowed by regulation.




Day 6




GENERAL:

ASME Sec. V is NDT procedure/methods code and is app

referenced by the relevant construction code. The extent oacceptance standards is given in relevant construction co

NDT equipment and their calibration shall be as per ASM

Examiner is NDT person in employment of fabricator or re

Inspector means Authorized Inspector who finally accepts

FOR RT:Satisfactory radiograph shall meet requirements of densit

hole for hole type and designated wire for wire type).

Backscatter:

Light image of B on dark background - Unacceptable

Density Limitations:

Min 1.8 for X Ray / 2.0 for G-RayMax 4.0 for X / G Ray

Density Variation = -15 % to + 30%

Double wall viewing (DWDI) - Up to 3.5” outside diamete




Penetrameter Selection: Table T-276. Thickness includes

But not backing. (?)

Penetrameter shall be normally placed on source side. If n

be placed on film side with lead letter “F”.

T276.2

(a) Welds With Reinforcements. The thickness on which t

the nominal single-wall thickness plus the estimated weld

to exceed the maximum permitted by the referencing Codrings or strips shall not be considered as part of the thickn

The actual measurement of the weld reinforcement is not




FOR PT:

Control of Contaminants: Sulphur (for Nickel alloys) shall

residue. Chlorine + Fluorine (for S.S. and Titanium) shall residue.

Temp. shall be between 10oC to 52oC, for standard procePenetrants are colour (visible) type and fluorescent type.

water washable

post emulsifying

solvent removable

Thus, total 6 categories of penetrant are available.

Emulsifier is applied after applying penetrant and required

completed.

Lipopholic emulsifier is applied without pre-rinsing.

Hydropholic emulsifier is applied after pre-rinsing.

For dwell time for penetrant and developer refer Table T-6 After applying developer, interpretation shall be done with

All penetrant materials should be from same manufacture




FOR MT:

Prod Technique:

Use direct (rectified) current for magnetization

Prod spacing 3” to 8”

Useful for surface and sub-surface defects.

Yoke Technique:

Use D.C. or A.C. or permanent magnet

Suitable for surface defects only.

Calibration:

Equipment Ammeter to be calibrated once a year compar

Ammeter, take 3 readings. Deviation shall not exceed ±10

Lifting Power of Yokes

AC shall have lifting power of at least 4.5 kg (10 lbs.)

DC shall have lifting power of at least 18.1 kg (40 lbs.)Minimum two examinations on each area, the second is p




SE-797 UT MEASUREMENT:

Pulse-echo method can be adopted up to 200°F

Apparatus: 3 types

CRT read out

CRT + direct read outDirect thickness read out

Search Units: 3 types

- Straight beam contact type

Delay line type (delay block to minimize dead zone)

Dual element type. There are two crystals set ata small range. Low roof angle used for higher

range and higher angle for low range.




High thickness measurement:

Use of multiple echoes is made. (i.e., for thickness betwee

60mm, use 10mm calibration block then 5th back echo w

6th will be 60mm. Set the 5th echo to zero and 6th at the s

screen is calibrated to 50-60mm.

While taking measurement for high temperature condition

1% per 55°C (100°F) results. Hence temperature correctio

CRT read out is recommended on corroded and rough su
















Good Luck!



Documents

Understanding API ICP653 Reading 11-Worksheet-7