RT Acceptance Criteria
April 11, 2017 | Author: Andry Rimanov | Category: N/A
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RADIOGRAPHIC TESTING COMPARATIVE ACCEPTANCE CRITERIA (UNACCEPTABLE WHEN) LEGENDS: IP: Incomplete Penetration IF: Incomplete Fusion IC: Internal Concavity EI: Elongated Indication RI: Rounded Indication BT: Burn Through ESI: Elongated Slag Inclusion IFD: Incomplete Fussion due to Cold Lap ISI: Isolated Slag Inclusion HB: Hollow Bead EU: External Undercut IU: Internal Undercut AI: Aligned Indication LOF: Lack of Fusion LI: Linear Indication NA: Not Applicable ICP: Inadequate Cross Penetration T/t : Nominal wall thickness of the thinner of two component joined by a butt weld . TW: Thick. of weld excluding any reinforcement. TWI: Thick. of weld including weld reinforcement ASME SEC. VIII (2008a) / API 650 (2007) ASME B31.3 (2008) API 1104 (2005) / ANSI B31.8 / B31.4 ANSI B31.1 (2001) REF. CODE PIPELINE
DEFECTS CRACKS Shallow Crater / Star
Other then shallow or star = Zero
PRESS. VESSEL & STORAGE TANKS
PRESS. VESSELS
UW - 51 (b)
UW- 52 (SPOT)
Zero
Zero
Zero
Zero
PLANT PIPING
POWER PIPING
(APPLICABLE FOR GIRTH & MITTER GROOVE)
NORMAL
SEVERE
CATEGORY D
HIGH PRESSURE
Zero
Zero
Zero
Zero
Zero
Zero
> 1/32" (1 mm) & 0.2Tw
Zero
Zero
Zero
> 5/32" (4 mm) length
IP Depth
NA
Length without HI LOW
Each indication >1" (25mm) /Aggregate length >1" in continuous 12" OR exceeds 8% of weld length in any weld < 12" (300mm) in length
Cummulative Length Length due to HI LOW Inadd. Cross Penetration
> 1/5" (38mm) in 6" weld
IF Open to surface Length
> 1/5" (38mm) in 6" weld
Each indication >2" (50 mm) /Aggregate length 3" in conctinuous 12" (300 mm) Length of Individual > 2" (50 mm), Aggregate Length > 2' in any continuous 12" (300 mm) Zero
Zero
Zero
Zero
Zero
Length of each indication > 1" (25 mm)
Wall thk.(mm) 1" per 12" weld / 8% of weld length in any weld < 12" (300 mm) in length
Aggregate Due to COLD LAP Aggregate length
IC Depth (Suck Up)
BT Size & Density
Zero > 1 mm & > 0.2 TW
Length of Each indication > 2" (50 mm),
Height 1/16" (1.5 mm) 1/8" (3 mm) 3/32" (4 mm)
Aggregate length > 2" in 12" (300 mm) contimuous length / > 8% of weld length Density exceed base metal: Refer to Burn Through for accetance
NA
NA
When there is an abrupt change in denstiy
For Pipe O.D > 2.375 " (60.3 mm)
NA
NA
Zero
Size > 1/4" (6 mm) max. dimension
Total joint thickness, including weld reinforcement, < Tw
Zero
Zero
Zero
Zero
and if the longest indication seperated by less than 3L, L is the length of Longest indication . Max length of indication > 19 mm. AI shorter then 6 mm is acc for any plate
Densaity > base metal / dimension > thinner wall thick joined & density in any portion exceeds rhen thinnest adjacent parent material.
Except when the distance b/w successive imperfection > 6L, where L is the longest imperfection in the group
Density > base metal : aggregate length of separate BTs > 1/2"per 12" (300 mm) weld or total weld For Pipe O.D < 2.375" (60.3 mm)
Except when the distance b/w successive imperfection > 6L, where L is the longest imperfection in the group
Density > Base metal and 1/4" (6 mm) max. dimension
If the longet indication's considered are separate by at least 3L. The ma. Length of unacceptable indication's shall be > 3/4". Any such indication longer then 1/4" shall be unacceptable for any plate thickness.
Density > base metal and dimension > thinner wall thick. Desity of BTs > base metal
UNDERCUTTING
Aggregate length of EU & IU combinnation
Zero
Zero
Zero
> 2" ( 50mm) per 12" weld or > 1/6 of weld length
Depth ACCUMULATION OF IMPERFECTIONS
> 1/32" (1 mm) & Tw/4
NA
> 1 .5 mm &TW/4 OR 1 mm)
AOI (excluding IP due to HI-low & UC) > 2" (50 mm) in any continuous 12" (300) OR aggregate length exceeds 8% of weld length
ALIGNED INDICATIONS
Prepared By: Zaheer Ahmed Sajid
NA
If the sum of the longest Any group of AI which have dimensions of all such aggregate length > t in a indication > T in a length of length of 12t 6T
Any group of AI which have aggregate length > t in a length of 12t
Date: 10.09.2010
NA
NA
NA
NA
sheet 1 of 3
1. Rounded Indications: Indications with a maximum length of three times the width or less on the radiographed are defined as R. I., the indication may be circular, elliptical, conical or irregular in shape and may have tails. When evaluating the size of an indication, the tail shall be included. The indication may be from any imperfection in the weld, such as porosity, slag or tungston. 2. Aligned Indications: A sequence of four or more rounded indications shall be considered to be aligned when they touch a line parallel to the length of the weld drawn through the centre of the two outer rounded indications. 3. Linear Indications: crack, Incomplete Fusion, Incomplete Penetration, elongated Slag Inclusion 4. Elongated Indications: Length of indications greater then 3 times the width Fluid service: a general term concerning the application of a piping system, considering the combination of fluid properties, operating conditions, & other factors which establish the basis for design of the piping system. Category D Fluid Service: a fluid service in which all the following apply: (1) the fluid handled is nonflammable , nontoxic, and not damaging to human tissues.
(2) the
Category M Fluid Service: a fluid service in which the potential for personnel exposure is judged to be significant and in which a single exposure to a very small quantity of a toxic fluid, caused by leakage, can produce serious irreversible harm to persons on breathing or bodily contact, even when prompt restorative measures are taken. High Pressure fluid Service: a fluid service for which the owner specifies the use of chapter IX ( is considered herein to be pressure in excess of that allowed by the ASME B16.5 PN 420 (Class 2500) rating for the specific design temperature & material group. However , there are no specified pressure limitations for the application of these rules. Normal Fluid Service: a fluid service not subject to rules for Category D, Category M, or High Pressure Fluid Service. Severe Service: APPENDIX 4 (a) Image Density , Density within the image of the indication may vary & is not a criterion for acceptance or rejection (b) Relevant Indication: , ref. table 4.1, FOR 1/10 t for t less than 1/8 (3 mm), 1/6 t for t 3 mm to 6 mm, 1/32 t for t greater then 6 mm to 50 mm & 1/16 t for t greater then 50 mm. (c ) Maximum Size of RI : 1/4 t or 4 mm, except Isolated Indications seperated from others by 25 mm or moremay be 6 mm. For t greater then 50 mm is 10 mm. (d) Aligned RI : the sum is less than t in a length of 12t, Fig 4-1, Spacing and Length of group shall be as per Fig 4-2 (e) Spacing : distance between adjacent RIs is not a factor. (f) RI Charts : Fig 4-3 through 4-8 (g) Weld Thickness less then 3mm thk: Max. 12 no. of RI in 150 mm length of weld.
.
(h) Clustered Indications : 4 times as for random indications. Cluster Length exceeds the lesser of 1" (25mm) or 2t. Where more than one cluster is pesent, the sum of the lengths of the clusters shall not exceed 25mm in 150mm weld length. Rounded Indication Chart (APPENDIX 4, TABLE 4-1) Acceptance Standard for Radiographically determined Rounded Indications in welds Maximum size of acceptable
Thickness (t)
Rounded Indication
Random
Maximum size of Non Relevant Indication
Isolated
inches
mm
inches
mm
inches
mm
inches
Less than 1/8
3.17
1/4t
6.35t
1/3t
8.5t
1/10t
2.5t
Less than 1/8
3.17
0.031
0.792
0.042
1
0.015
0.39
Less than 3/16
4.76
0.047
1.19
0.063
1.6
0.015
0.39
Less than 1/4
6.35
0.063
1.58
0.083
2.1
0.015
0.39
Less than 5/16
7.93
0.078
1.98
0.104
2.64
0.031
0.79
Less than 3/8
9.52
0.091
2.38
0.125
3.175
0.031
0.79
Less than 7/16
11.11
0.109
2.77
0.146
3.7
0.031
0.79
Less than 1/2
12.7
0.125
3.77
0.168
4.3
0.031
0.79
Less than 9/16
19.05
0.142
4.76
0.188
4.8
0.031
0.79
Less than 5/8
15.87
0.156
3.96
0.21
5.3
0.031
0.79
Less than 11/16
17.46
0.156
3.96
0.23
5.8
0.031
0.79
3/4 to 2, inclus. over 2
19.05 50.8
0.156 0.156
3.96 3.96
0.25 0.375
6.35 9.5
0.031 0.063
0.79 1.6
(Table T - 232.2) Wire IQI
TABLE T - 276 for the selection of Penetrameters (SOURCE SIDE)
A
B
C
D
zaheer ahmed sajid
Essential Wire
Essential Dia of Wire
mm
No.
mm
Designation
Thk. (mm)
Nomianal Single-Wall Material Thickness Range
Designation & dia., in. ASTM
mm
Dia (No.)
Inches
Hole -Type
0.0032
(1)
Upto 0.25, incl.
Upto 6.4, incl.
5
0.2
12
0.32
0.004 0.005
(2) (3)
Over 0.25 through 0.375
Over 6.4 through 9.5
6
0.25
15
0.38
Over 0.375 through 0.50
Over 9.5 through 12.7
7
0.33
17
0.44
0.0063
(4)
Over 0.50 through 0.75
Over 12.7 through 19.0
8
0.41
20
0.51
0.008
(5)
Over 0.75 through 1.00
Over 19.0 through 25.4
9
0.51
25
0.64
0.01
(6)
Over 1.00 through 1.5
Over 25.4 through 38.1
10
0.64
30
0.76
0.013
(7)
Over 1.5 through 2.00
Over 38.1 through 50.8
11
0.81
35
0.89
0.016
(8)
Over 2.00 through 2.5
Over 50.8 through 63.5
12
1.02
40
1.02
0.02
(9)
Over 2.5 through 4.0
Over 63.5 through 101.6
13
1.27
50
1.27
0.025
(10)
Over 4.0 through 6.0
Over 101.6 through 152.4
14
1.6
60
1.52
0.032
(11)
Over 6.0 through 8.0
Over 152.4through 203.2
16
2.54
80
2.03
0.04
(12)
Over 8.0 through 10.0
Over 203.4 through 254.0
17
3.2
100
2.54
0.05
(13)
Over 10.0 through 12.0
Over 254.0 through 304.8
18
4.06
120
3.05
0.063
(14)
Over 12.0 through 16.0
Over 304.8 through 406.4
20
6.35
160
4.06
0.08
(15)
Over 16.0 through 20.0
Over 406.4 through 508.0
21
8.13
200
5.08
0.1
(16)
0.126
(17)
0.16
(18)
0.2
(19)
0.25
(20)
0.32
(21)
Sept 2010
Sensitivity S=V.W/T x 100
REF. CODE
API 1104 / ANSI B31.8 / B31.4 PIPELINE
DEFECTS SLAG/TUNGSTON INCLUSION / EI
UW - 51 (b)
UW- 52 (SPOT)
ANSI B31.3 (2008)
POWER PIPING
PLANT PIPING (APPLICABLE FOR GIRTH & MITTER GROOVE)
NORMAL
SEVERE
> of ISI 1/8" (3 mm) More then 4 ISIs with max. width 1/8" (3 mm) per 12" weld
ESI / ISI aggregate length
> 8% of weld length For Pipe O.D < 2.375" (60.3 mm)
EI length >: (a) 1/4" (6 mm) for t upto 3/4" (19 mm) (b) 1/3t for t from 3/4" (19 mm) to 2 1/4" (57 mm) (C) 3/4" for t over 21/4"
Slag inclusion or cavities are unacceptable . If the length of any such indication > 2/3t
Length > 3 x thinnest wall thickness joined (wagon tracks: width > 0.8 mm is considered as separate indications) ESI > 1/16" (1.6 mm) OR Width of ISIs > 1/2 of thinnest wall joined and aggregate Length > 2 x thinnest wall
ESI/ISI aggeregate length
EI length : 1/4" (6 mm) for t upto 3/4" (19 mm) inclusive , Individual length > 2 Tw 1/3t for t from 3/4" (19 mm) to Individual width > (3 mm) & 2 1/4" (57 mm) inclusive, 3/4" Tw/2 (19 mm) for t over 2 1/4" (57 Cummulative length > 4Tw in mm) any 6" (150 mm) weld length where t is the thk. Of the thinner portion of weld
Individual length > Tw/3 Individual width > 3/32" (2.5 mm) & Tw/3 Cummulative length > Tw in any 12" Tw weld length
> 8% of weld length
POROSITY / RI
Finish Pass / Surface Hollow Bead
NA See BPV Sec. VIII, DIV. 1 Appendix 4
Individual > 1/8" (3 mm), > 25% of thinest wall thk. & Distribution of Scattered as per Fig 19 or 20 Diameter of cluster & aggregate Length in any continous 12" > 1/2" (13 mm) Individual & Aggregate length > 1/2" (13 mm)per 12" weld Length of each indication > 1/2" (13 mm) aggeregate length > 2" per 12" weld / > 8% of weld
RI inexcess of that shown as acceptable in appendix 4 of ASME section VIII code
RI are not a factor in the acceptability of weld not required to be fully radiographed
individual HB > 1/4" (6mm) length & < 2" (50 mm) separation
In excess of that shown in appendix A-250 of section I of ASME BPV. Any group of indication in the line that have length > t in a length of 12t except where the distance b/w the sucessive indication exceed 6L. L is the length of longest indication in group
Size & distrib. Internal Surface or exposed
SURFACE FINISH
NA
Individual length > Tw/4 & > 4mm Individual width > (2.5 mm) & Tw/4 Cummulative length > Tw in any 12" Tw weld length
> of ESI 1/16" (1.6 mm) > 1/2" (13 mm) per 12" weld
Width of ISI
Cluster
HIGH PRESSURE
> 2" (50 mm) per 12" weld
ISI aggregate length
Individual / scattered size
CATEGORY D
ESI > 2" (wagon tracks: width > 0.8 mm is considered as separate indications)
Width of ESI
Width
PRESS. VESSEL
ANSI B31.1 (2001)
For Pipe O.D > 2.375" (60.3 mm)
ESI aggregate length
ESI
ASME SEC. VIII (2008a) / API 650 (2007) PRESS. VESSEL & STORAGE TANKS
Zero
for Tw 1/4" (6mm) Limit is Same as for Appendix 4 For TW > 1.5 x Appendix 4
See table 4.1 Appendix 4
Zero Reinf. Below then the out side of pipe
NA
NA
NA
NA
Roughness: > 500 min Ra per ASME B46.1
Reinf. Above then the out side surface of pipe by more then 1/16" (1.59 mm)
NA
> 12.5 ,u m R
Surface Porosity of Exposed Slag Inclusion = Zero
width of reinf. >1/8" (3.17 mm) then the original groove NA
REINFORCEMENT Or internal protrusion Height
PIPE OR FITTING DISCONTINUTIES WELDER TEST
NA
NA
for Tw in
(mm)
< 1/4" (6)
Arc Burns, Long Seam discontinuties & other discont. Detected by RT shall be reported to client
NA
NA
NA
Date: 10.09.2010
(mm) (1.5)
Limit is twice then Normal / Severe
Wall thk.(mm) Height 1/4" (6) , 1/2", < 2" (51)
>1/2" (13) , 2" (51)
>1" (25)
> 1/16"
(5)
NA
Crack, IP, BT etc. AS PER ASME SEC. IX, 2007 (a) Linear Indication : (1) Crack, IP, IF (2) ESI inclusion length > 1/8" (3 mm) for t upto 3/8" (10 mm), 1/3t for t > 3/8 < 2 1/4", 3/4" (19 mm) for t > 2 1/4" (57 EU > 1/32" (0.79 mm) deep or 12.5% of W.T. which mm) (3) Group of slag inclusion in line that have aggregate length > t in a length of 12t. except when 2 Indications ever is smaller & 2" in any contins. 12" length of weld seperated by 6L, where L is the Longest Inperfection in group
Prepared By: Zaheer Ahmed Sajid
height in > 1/16"
NA
NA
1/8" (3) 3/32" (4)
NA
AS PER ASME SEC. IX, 2007 (b) Rounded Indication: (1) > 20% of t or 3 mm which ever is smaller (2) TW < 1/8' (3 mm), no. of rounded indications > 12 in a 150 mm (6") length (3) TW > 1/8" refer Appendix I RI less than 0.8 mm Max. dia not to be consider in RT acceptance.
sheet 2 of 3
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