api 579-2_13.1 rev1

1 LaminationAPI 579-1 Fitness-For-Service AssessmentPage1

Plant ID:Meren PPEquipment Number: ABC-1234Equipment: Test SeparatorEquipment Type:Pressure VesselDate: 25th March 2015

1Introduction

The following Level 1 and Level 2, Fitness-For-Service assessment was carried out in accordance with: API 579-1 Part 13, for pressurized components with laminations, excluding HIC or SOHIC damage.

Review of the process operating conditions indicate that the vessel is not operating in the creep range, that is, the design temperature is less than the temperature limit specified in API 579-1, Part 4, Table 4.1. and that the vessel has sufficient material toughness for design conditions.

The vessel which was constructed to ASME VIII, Div. 1 rules, is not in cyclic service and the shell is a Type 'A' Component as defined in API-579-1, Part 4, paragraph 4.2.5.

2Summary

Both the Level 1 and Level 2 assessment criteria are not satisfied as the the lamination is in close proximity to a major structural discontinuity (a structural support); see STEP 6, part 4 of this assessment for details. As per Appendix 1 and API 579-1, 13.2.5.2, a Level 3 Fitness-For-Service assessment for laminations shall be performed.

3Contents

Page1Introduction12Summary13Contents14Nomenclature25Vessel Data36Level 1 and 2 Assesment per API 579-1, Part 1337Figure 1 - Typical Lamination78Figure 2 - Weld Joint Spacing and Multiple Laminations89Figure 3 - 910Figure 4 -1011Test Separator Pictures1112Appendix 1 - Overview of the FFS Assessment Procedure12

API 579-1 Fitness-For-Service AssessmentPage2


4Nomenclature

2adepth of through-wall embedded crack associated with a laminationclamination dimensions in the circumferental direction2clength of through-wall embedded crack associated with a laminationCTPcritical thickness pathtest separator centre line at the 6 o'clock positionDshell inside diameterEweld joint efficiencyFCAfuture corrosion allowanceFFSFitness-For-ServiceHIChydrogen inducted crackingIRVisions integrity reportLhlamination heightLmsdspacing to the nearest major structural discontinuityLslamination-to-lamination spacingLwspacing to nearest weld jointLOSSamount of uniform metal loss at the time of the assessment.MAWPmaximum allowable working pressureMAWPCmaximum allowable working pressure based on circumferential stressPinternal design pressurePAUTphased array ultrasonic testing Rinside radius corrected for LOSS and FCA as applicableRATrope access teamslamination dimension in the longitudinal directionSallowable stressSOHICstress-orientated hydrogen induced crackingtcminaverage measured wall thickness of the component based on the circumferential CTP determined at thetime of the inspection.tccorroded wall thickness, allowing for future corrosion losstminminimum required wall thickness of the component (see API 579-1, Annex A, paragraph A.2)tCminminimum required thickness of a conical or cylindrical shell based on the stresses in the circumferentialor hoop direction (see API 579-1, Annex A, paragraph A.2)tLminminimum required thickness of a conical or cylindrical shell based on the stresses in the longitudinaldirection (see API 579-1, Annex A, paragraph A.2)tmmminimum measured thickness determined at the time of the inspectiontnomnominal or furnished thickness of the component adjusted for mill undertollerance as applicabletrduniform thickness away from the local metal loss location established by thickness measurements at thetime of the assessment.UTultrasonic testing



5Vessel Data

Material:SA-516 Grade 70, Year 1967Allowable Stress In Tension (S):17500psiDesign Pressure (P):500psig @ 100 FInside Diameter (D):34inInside Radius (R):17.125in(with metal loss and FCA applied)Corrosion Allowance (FCA):0.125inWeld Joint Efficiency (E):0.85Nominal Thickness (tnom):1.000inUniform Thickness Away From Local Metal Loss (trd):1.006inLOSS:0.00intcmin:0.586in(A.12)

6Perform a Level 1 and 2 Assesment per API 579-1, Part 13.

a)STEP 1 Determine if there is any surface bulging on either the inside or the outside surface of the component at the location of the lamination. If there is surface bulging, then evaluate the lamination the lamination as a blister using the Level 1 Assessment method in API 579-1 Part 7.

Does the inspection report indicate surface bulging on either the inside or outside surface of thecomponent at the location of the lamination:

Lamination 1:No

(b)STEP 2 - Determine the information in paragraph 13.3.3.1:

Table1: Size, Location and Spacing for Laminations

Data required for Level 1 and Level 2 AssessmentLamination Identification1234Dimensions s (1) (3)12.023inDimensions c (1) (3)13.809inLamination Height Lh (1)0.018inEdge-to-Edge Spacing to the nearest lamination Ls (2)100.0in (4)Minimum Measured Thickness tmin (1)0.473inSpacing to the Nearest Weld Joint Lw (2) (3)39.0inSpacing to the Nearest Structural Discontinuity Lmsd (2) (3)5.992inSurface Bulging PresentNoThrough-Wall Cracking (Yes/No)NoInternal Metal Loss at Lamination Location0.0inAre there two or more laminations at different depthsNoTotal :1Are both laminations on the same planeN/ANotes:1. See Figure 13. See Figure 42. See Figure 24. Arbitrarily large value as only one lamination was found in the area inspectedAPI 579-1 Fitness-For-Service AssessmentPage4


(c)STEP 3 If there are two or more laminations on the same plane, there is no indication of through thickness cracking, and the spacing does not satisfy Equation (13.1), then the laminations shall be combined into a single larger lamination in the assessment. If there are two or more laminations at different depths in the wall thickness of the component and the spacing does not satisfy Equation (13.1), then the group of laminations shall be evaluated as equivalent HIC damage using the Level 1 Assessment method in Part 7. In applying this criterion, the spacing shall be measured parallel to the wall thickness. Applying Equation (13.1):

Ls > 2tc

2tc = 2(trd - FCA)=1.762inLs = 100.0in(arbitrarily large value as only one lamination found in the area inspected)Is Ls > 2tc ?YES

Equation (13.1) is satisfied.

Are there two or more laminations on the same plane:NOIs there any indication of through wall thickness cracking:NO

(d)STEP 4 If Equation (13.2) is satisfied, proceed to STEP 5; otherwise, evaluate the through-thickness component of the lamination as a crack-like flaw using the Level 1 Assessment method in Part 9. In this evaluation, the crack depth shall be equal to 2a = Lh and the crack length shall be equal to:

2c = max[s,c]

Applying Equation (13.2):Lh max[s,c]

1)Lamination 10.09max[s,c] = 1.243in Lh =0.018in0.0181.243in

Equation (13.2) is satisfied for lamination 1.

(e)STEP 5 Determine the wall thickness to be used in the assessment using Equation (13.3) or Equation (13.4), as applicable. Applying Equation (13.3):

tc = tnom - LOSS - FCA

tc = tnom - LOSS - FCA =0.875in

Equation (13.4) may also be applied:tc = trd - FCA =0.881in



(f)STEP 6 If all of the following conditions are satisfied, proceed to STEP 7; otherwise, the lamination is not acceptable per the Level 1 Assessment procedure.

1)The inspection report indicates no evidence of through-thickness cracking.

2)The lamination is not surface breaking in accordance with Equation (13.5):tmm 0.10tc

i)Lamination 10.10 tc = 0.0881intmm = 0.473in0.4730.0881in


3)The distance between any edge of the lamination and the nearest weld seam satisfies Equation(13.6):Lw max[2tc, 1.0 in]

2tc =1.762infrom Equation (13.1)

i)Lamination 1Lw =39.0inmax[2tc, 1.0 in] = 1.76in39.01.76in


4)The distance from any edge of the lamination to the nearest major structural discontinuity satisfiesEquation (13.7):Lmsd 1.8 (Dtc)

1.8 (Dtc) =9.85in

i)Lamination 1Lmsd =5.992in5.992 2tc

2tc = 2(trd - FCA)=0.875in

Ls = 11.0in

Is Ls > 2tcYES

Equation (13.1) is satisfied

Are there two or more laminations on the same plane:YESAre there two or more laminations at different depths:NOIs there any indication of through wall thickness cracking:NO

(d)STEP 4 If Equation (13.2) is satisfied, proceed to STEP 5; otherwise, evaluate the through-thickness component of the lamination as a crack-like flaw using the Level 1 Assessment method in Part 9. In this evaluation, the crack depth shall be equal to 2a = Lh and the crack length shall be equal to:

2c = max[s,c].

Applying Equation (13.2):Lh max[s,c]

1)Lamination 10.09max[s,c] = 0.405in Lh =0.125in0.1250.405inEquation (13.2) is satisfied for lamination 1

2)Lamination 20.09max[s,c] = 0.585in Lh =0.100in0.1000.585inEquation (13.2) is satisfied for lamination 2

API 579-1 Fitness-For Service AssessmentPage4

Plant IDA PlantEquipment Number: ABC-1234Equipment: Test SeparatorEquipment Type:VesselDate: 17th March 2015

(e)STEP 5 Determine the wall thickness to be used in the assessment using Equation (13.3) or Equation (13.4), as applicable. Applying Equation (13.3):

tc = tnom - LOSS - FCA

tc = tnom - LOSS - FCA =0.4375in

(f)STEP 6 If all of the following conditions are satisfied, proceed to STEP 7; otherwise, the lamination is not acceptable per the Level 1 Assessment procedure.

1)There is no indication of through-thickness cracking.Inspection report indicates no evidence of through-thickness cracking.

2)The lamination is not surface breaking in accordance with Equation (13.5):tmm 0.10tc

i)Lamination 10.10 tc = 0.04375intmm = 0.325in0.3250.04375inEquation (13.5) is satisfied for lamination 1.

ii)Lamination 20.10 tc = 0.04375intmm = 0.325in0.3250.04375inEquation (13.5) is satisfied for lamination 2.

3)The distance between any edge of the lamination and the nearest weld seam satisfies Equation(13.6):Lw max[2tc, 1.0 in]2tc =0.875infrom Equation (13.1)

i)Lamination 1Lw =10.0inmax[2tc, 1.0 in] = 1.0in10.01.0inEquation (13.6) is satisfied for lamination 1.

ii)Lamination 2Lw =25.5inmax[2tc, 1.0 in] = 1.0in25.51.0inEquation (13.6) is satisfied for lamination 2.



4)The distance from any edge of the lamination to the nearest major structural discontinuity satisfiesEquation (13.7):Lmsd 1.8 (Dtc)1.8 (Dtc) =13.04in

i)Lamination 1Lmsd =42.0in42.013.04inEquation (13.7) is satisfied for lamination 1.

ii)Lamination 2Lmsd =28.0in28.013.04inEquation (13.7) is satisfied for lamination 2.

5)If the lamination is in hydrogen charging service, then the planar dimensions of the laminationsatisfy Equations (13.8) and (13.9):s 0.6 (Dtc)c 0.6 (Dtc)

Review of process operating conditions indicates the vessel is not in hydrogen service.

(g)STEP 7 Determine the MAWP for the component (see Annex A, paragraph A.2) using the thickness from STEP 5. The component with the lamination is acceptable for operation at this calculated MAWP.

MAWP.In calculating the component MAWP, P 0.385SE and tcmin 0.5R (Longitudinal Joints), andsupplimental loads are negligible, so Equation (A.10) pertains.

Lamination 1Lamination 2S =17500S =17500psiE =1E =1tc = 0.4375tc = 0.4375inR =60.0625R =60.0625in

Using the maximum value or R above for Lamination 1 and Lamination 2, R =60.0625in

126.9167012018psig











Lamination Plan ViewSection A-ACross Section of LaminationFigure 1 - Typical Laminationa) Planar View of Laminations Close to a Weld Seam and to Other Laminationsa) Cross Sectional View of Laminations Close to a Weld Seam and to Other LaminationsFigure 2 - Weld Joint Spacing and Multiple Laminations

api 579-2_13.1 rev1

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