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Standardization
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Applicable scope
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The fuel gas, water, the coal gas, air, heating, vapor and other ordinary fluid conduit uses steel pipe
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The petroleum＆gas industry transport uses steel pipe
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The petroleum＆gas industry transportation uses steel pipe
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Type
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Q195、Q215、Q235
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L175——L483
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A、B、X42～X70
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Size
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Body
Out
Diameter
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D＜508 ±0.75%D
D≥508 ±1.00%D
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D＜508 ±0.75%D
D≥508 ±1.00%D
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D＜508 ±0.75%D
508≤D≤914 -0.25%D～+0.75%D
D＞914 -3.20～+6.35
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Jet
Out
Diameter
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D＜508 ±0.75%D or ±2.5 (Minimum)
D≥508 +0.50%D or ±4.5 (Minimum)
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D≤273.1 -0.40～+1.59
D＞323.9 -0.79～+2.38
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D≤273.1... -0.40～+1.59
D＞273.1... -0.79～+2.38
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Deviation
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Wall Thickness
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<508
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±12.5%t
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-12.5%t～+15.0%t
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-12.5%t～+15.0%t
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≥508
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±10.0%t
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L175～L245 -10.0%t～+17.5%t
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≤B Grade -12.5%t～+17.5%t
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L290～L555 -8.0%t～+19.5%t
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≥X42 -8.0%t ～+19.5%t
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Ellipticity
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Within 100mm of Jet Out ±1%D
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Within the Jet scope of 101.6 which its D＞508,the maximum OD≤1%D of the gauge and the minimum OD≥1%D of the gauge
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Within the Jet scope of 101.6 which its D＞
508,the maximum OD≤1%D of the gauge and the minimum OD≥1%D of the gauge
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Bending
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≤0.2% of the total length
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≤0.2% of the total
length
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≤0.2% of the total
length
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Jet bevel
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Bevel angle 30°--35°
Shoulder 1.6±0.8
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Bevel angle 30°--35°
Shoulder 1.59±0.79
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Bevel angle 30°--35°
Shoulder 1.59±0.79
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Cuts slanting
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D＜813 , ≤1.6
D≥813 , ≤3.0
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＜1.59
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＜1.59
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Inlaying
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t≤12.7
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0.35t and ≤3.0
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≤1.59
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≤1.59
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t＞12.7
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0.25t
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Minimum between 0.1251 and 3.18
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Minimum between 0.1251 and 3.18
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Welded joint surplus height
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T≤13…＜3.2
t＞13 ＜4.8
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T≤12.7…＜3.18
t＞12.7 ＜4.76
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T≤12.7…＜3.18
t＞12.7 ＜4.76
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Chemical analysis
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Select a sample from each batch
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Select two samples from each batch
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Select two samples from each batch
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Stretch testing sample
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Select a welded joint from each testing lots
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Material: Select a sample from each batch
Spiral welded joint: Select a sample from each batch
Butt-welded joint: select a sample within 50
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Material: Select a sample from each batch
Spiral welded joint: Select a sample from each testing lotsButt-welded joint: select a sample within 50
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Oriented bend testing
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Not available
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Select a front-side bending sample and a reverse-side bending sample from each testing lots
Select a front-side bending sample and a reverse-side bending sample within 50 Butt-welded joints
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Select a front-side bending sample and a reverse-side bending sample from each testing lots
Select a front-side bending sample and a reverse -side bending sample within 50 Butt-welded joints
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Break toughness testing
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Not available
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Per the contracts, select
3 charpy impacts from each batch
When D≥508, select 2 drop hammer impacts from each batch
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Per the contracts, select
3 charpy impacts from each batch
When D≥508, select 2 drop hammer impacts from each batch
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NDT
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Implement UT or XT to the Repair welded joint, Butt-welded join and surround welded joint; inspect 20% of the spiral welded joint of the pipes; inspect 100% of the spiral welded seam which are the pipes used for flammable gas transportation
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Implement 100% UT or XT; implement XT to the butt-welded joint ,T- welded joint and 203mm of the jet
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Implement 100% UT or XT; implement XT to the butt-welded joint ,T-welded joint and 203mm of the jet
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D: Steel Pipe Average External Diameter ,mm T: Steel pipe normal wall thickness ,mm
[σ]: Hydrostatic pressure test stress, MPa
L: Length of single steel pipe P: Hydrostatic pressure test stress, MPa
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