seam welded tube & pipe
TRANSCRIPT
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John Shingledecker, Ph.D.Sr. Technical Executive
Gen 3 CSP Summit 2021August 25, 2021 (Virtual)
Seam Welded Tube & PipeTrack A: High-Temperature Nickel-Based Alloys
Projects:DE-EE0008367, DE-EE0009378
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What effects cost?
Product Form Selection§ Based on desired sizes§ Differences in product form costs are driven by:
– Processing time– Energy intensity– Overall process yield
Seamless Tube
0.25 0.5 1 2 3 4 5 0.25 0.5 1 2 3 4 50.025 0.0250.05 0.05
0.075 0.0750.1 0.1
0.15 0.150.2 0.20.3 0.30.5 0.5
0.75 0.751 1
1.25 1.25
Welded Tube Welded Tube
0.25 0.5 1 2 3 4 5 0.25 0.5 1 2 3 4 50.01 0.010.025 0.0250.05 0.050.075 0.0750.1 0.10.15 0.150.2 0.20.25 0.25
Welded + 30% Re-drawn Tube Welded + 30% Re-drawn Tube
0.25 0.5 1 2 3 4 5 0.25 0.5 1 2 3 4 50.175 0.01750.035 0.0350.053 0.0530.07 0.070.105 0.1050.14 0.140.18 0.18
Welded Pipe Welded Pipe
5 10 15 20 25 30 5 10 15 20 25 300.25 0.250.5 0.5
0.75 0.751 1
1.25 1.251.5 1.5
Seamless Pipe Seamless Pipe
5 10 15 20 25 30 5 10 15 20 25 300.5 0.51 12 23 34 4
Red: Sizes not possible or unlikely to be possible with current processes for these alloys
Green: Possible tube size
Outer Diameter (in) Outer Diameter (in)
Wal
l Thi
ckne
ss
(in)
Wal
l Thi
ckne
ss
(in)
Yellow: Sizes requiring addition research for cost estimation purposes or possible but not demonstrated for similar alloys
Wal
l Thi
ckne
ss (i
n)
Wal
l Thi
ckne
ss (i
n)
Outer Diameter (in) Outer Diameter (in)
Wal
l Thi
ckne
ss
(in)
Wal
l Thi
ckne
ss
(in)
Outer Diameter (in) Outer Diameter (in)
Wal
l Thi
ckne
ss (i
n)
Wal
l Thi
ckne
ss (i
n)
Outer Diameter (in) Outer Diameter (in)
N06230 740H
Outer Diameter (in) Outer Diameter (in)
Wal
l Thi
ckne
ss (i
n)
Wal
l Thi
ckne
ss (i
n)
40
60
80
100
300
500
550 600 650 700 750 800
1100 1200 1300 1400
6
8
10
30
50
70
Stre
ss (M
Pa)
Average Temperature for Rupture in 100,000 hours (oC)
9-12Cr Creep-Strength Enhanced Ferritic Steels (Gr. 91, 92, 122)
Nickel-BasedAlloys
Std. 617CCA617
Inconel 740
Haynes 230
Advanced Austenitic Alloys (Super 304H, 347HFG, NF709, etc.)
Haynes 282
Average Temperature for Rupture in 100,000 hours (oF)
Stre
ss (k
si)
Materials Selection§ Higher tensile and creep strength = higher allowable
stresses§ Higher allowable stresses decrease wall thickness = reduced
cost/lb & improved cyclic capability§ *Note: alloy composition has a significant effect on cost (but
for this study, the nickel-based alloys all have similar cost)
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Putting it together: Techno-Economics
Tubing scenarios
1. Gen 2 CSP Baseline: 1200F, 2” OD2. Gen 3 Molten Salt Baseline: Conceptual design in ANL 20/03 – 1391F, 1.575 OD
3. Gen 3 Molten Salt Alternative: Scenario 1 scaled to Gen 3: 1350F, 2” OD
4. Gen 3 Gas Pathway Receiver: Current design of 1346F, 0.375” OD5. Gen 3 Generic 1” tube: Intermediate between Scenario 3 and 4: 1400F, 1” OD
6. Generic Heavy-wall tubing for sCO2: 1305F at high pressure and 3” ODPiping Scenarios
1. Gen 3 Gas Pathway Piping: 1346F, 28.2” OD
2. Gen 3 Gas Pathway Multi-Pipe Estimate: Modified Scenario 1: 1346F, 9” OD3. Gen 3 Headers: 1300F, 12” OD (lower stress application)
4. sCO2 Piping: higher stress for Scenario 3: 1300F, 14” OD
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1 2 3 4 5 6
740H
Cos
t/ft
Ratio
to S
eam
less
N0
6230
Tubing Scenario
SeamlessWeldedWelded+ Redrawn20% Reduction40% Reduction
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1 2 3 4 5 6
740H
Cos
t/ft
Ratio
to W
elde
d N0
6230
Tubing Scenario
SeamlessWeldedWelded+ Redrawn20% Reduction40% Reduction
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1 2 3 4
740H
Cos
t/ft
Ratio
to S
eam
less
N0
6230
Piping Scenario
SeamlessWelded (0.70 WSRF)Welded (0.95 WSRF this work)20% Reduction40% Reduction
Techno-economic study§ Baseline N06230§ 10 typical/anticipated Gen 2/3 product forms§ 740H reduces cost by >20% § 740H welded products can reduce costs by
>40%– For very small diameters and thin tubes, welded
production is the only cost-effective route
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Project Activities: Inconel® Alloy 740H®High-Temperature Testing & Analysis§ Relevant testing product forms (welded structures)§ New testing capabilities (multiaxial)
Manufacturing Development§ Supply chain engagement
Plate Welded Tube
Re-drawn tube
Coil
Seam-welded pipeInduction Bending
Low Cycle Fatigue of Tubes
Segment for creep testing at SIA Lab
Creep samples for EPRI Lab
Sample blank locations for tensile and fatigue
Ring Segment reserved for NDE
0-22”
22-44”
44-48”
Weld
Pressurized creep testingCross-weld creep
Post-test characterization
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Successful Welded Tube Production: Inconel® Alloy 740H®
§ Two successful trials:– Passed flattening tests– Passed NDE (eddy current)
§ Yield and Tensile Strength – After aging, all tubes met ASME minimum
criteria§ Tensile Ductility (Elongation)
– All materials exceed ASME Min Requirement
§ Pressurized room temperature burst test à failures outside of weld
§ Demonstrated re-drawn tube (2” tube re-drawn to 1” – met tensile requirements)
Coil Weight kg (lbs) Coil Thickness mm(in) Coil Width mm(in) Produced Tube Diameter mm(in)
ASTM Grain Size
Trial 1 112 (247) 1.65 (0.065) 76.7 (3.02) 25.4 (1) 7.5Trial 2 230 (508) 1.65 (0.065) 157 (6.19) 50.8 (2) 7.5
For more information see: J. Shingledecker, et al. “Materials Improvements for Improved Economy of High-Temperature Components in Future Gen 3 CSP Systems.” Proceedings to SolarPACES2018. October 2-5, 2018. Casablanca, Morocco. AIP Conference Proceedings
2126, 020004 (2019); https://doi.org/10.1063/1.5117512Weld Seam
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Successful Fabrication Activities with Welded Tubes
Autogenous welding (EPRI/SMC) – 1 to 2”
Diameter welded and redrawn tubing
Tube Bending (courtesy of TebunusTube Bending/John
Cockerill) – 2” Diameter Welded
Tubing
Solar Receiver Test Article (Courtesy of Brayton Energy) – 3/8” Diameter Welded+Redrawn
740H
1
2
3
4
5
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High-Temperature Performance of Welded Tubes§ Pressurized creep test program to
evaluate long-term performance of welded tubes and develop stress allowables– Longest test durations >4,000 hrs– 740H shows a strength debit with failures
at weld seam– 740H Re-drawn tube performance
approaching base metal strength – N06230 welded tube also shows a
strength reduction § Note: greater than is currently
approved with ASME’s standard tube efficiency factor
§ Currently engaging ASME with plans to incorporate this information into the code with new stress allowables in 2022
10
100
1000
20000 22000 24000 26000 28000
Stre
ss (M
Pa)
LMP (C=19.392)
Welded 1"Welded 2"Welded - OngoingWelded+Redrawn 1"Welded_Redrawn - OngoingSeamless TubeN06230 Welded
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Welded Pipe: World’s First 740H Seam-Welded Pipe§ Start with 48 in x 240 in x
0.75 in annealed plate§ Form 14 in OD Pipe§ GTA weld (740H filler, 8
passes)§ Solution anneal (1107°C)§ Radiography showed
acceptable level of porosity, no cracks or LOF
§ UST per ASTM E 213 showed no rejectable indications
20 ft long welded pipe (Swepco)
0.75” (19mm)
Pipe segment received by EPRI
0 5 10 15 20 25 30 35 40 450
5
10
15
20
X-Distance (mm)Y-
Dis
tanc
e (m
m)
17
3
10.5
0 5 10 15 20 25 30 35 40 45320
340
360
380
400
Har
dnes
s (H
V)
Cap Center Root
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High-Temperature Performance of Seam-Welded Pipe
§ Standard and large sample testing has now exceeded 10,000 hours§ Short-term tests also conducted on base metal and cross-welds from the induction
pipe bend§ WSRFs >0.90 for all test and appear to be trending towards unity at long-times (open
symbols are samples in-test)
Segment for creep testing at SIA Lab
Creep samples for EPRI Lab
Sample blank locations for tensile and fatigue
Ring Segment reserved for NDE
0-22”
22-44”
44-48”
Weld
HAZ/FL – 100X Weld Metal – 100x
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Ongoing research to enable reliability in Gen 3 CSP§ Example: GTI/Optimus STEP Program sCO2 (700C+) fired
heater– ~3% of tube-to-tube butt welds exhibited cracking
after PWHT§ Failure analysis confirmed Stress Relaxation
Cracking (SRxC) mechanism§ Methods for field NDE developed
– No cracking in tube-to-header, end plates, drains, etc.
§ New DOE Study SRxC (EPRI, Lehigh, Special Metals)– Assess root cause from examples of 740H cracking– Gleeble studies to evaluate fabrication variables– Transfer learnings into a specification document
First large-scale application of 740H welding (>1,600 welds) including a range of weld
geometries and thicknesses
Denuded Zones Axial Cracks near ID fusion line in Pipe Transition
R13, W4, #4
Intergranular, initiation at weld toe
Image to the rightID
ODIsolated cavities ahead of crack tip
R13, W4, #4
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