chemin cladding for sh in wte-plant, steamside approx. 500°c chemin prewin general assembly at...

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CheMinCladding for SH in wte-plant, steamside approx. 500°C

PREWIN General Assembly at Porto, November 17th-18th 2005www.chemin.de

Thomas HerzogThomas Herzog

Cladding with Nickelalloys(Ni-Cr-Mo and Ni-Cr-Mo-W)

on Superheater Tubesin WTE-Plants

Tested on-site for approximately 8,000 h T(steam) approx. 500°C,T(fluegas) approx. 630°C

Clads on single tubes, performed as spiral welding on the lathe

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Test Installation

Tube no. of superheater

Internal sample no.

Supplier Product UNS-no. DIN-no.

not sampled no sample Krupp VDM Nicrofer

5621 hMoW

06022,

Alloy C22

2.4602

11 014 Böhler Thyssen UTP A 5020 Mo 06650, Alloy 50

2.4850

12 015 Special Metals Inconel 686CPT 06686, Alloy 686

2.4606

13 016 Thyssen Thermanit Nimo T -/-, Alloy 650*

-/-

15 017 Haynes

Hasteloy G30 06030, Alloy G30

2.4603

16 018 Thyssen Thermanit 625 06625, Alloy 625

2.4831

failed** no sample Krupp VDM Cronix 70K 06008,

Alloy 70K

2.4658

*: Nimo T is similar to Alloy 650, see next slide **: Tube rupture after 2,800 hours

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Mayor Interest: Effects of Molybdenum and Tungsten?

Alloy 50 UTP A 5020 MoAlloy „650“ Thermanit Nimo TAlloy 686 Inconel 686CPT

Nickel in balance

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Material Test Reports of the welded Alloys

Alloy C N Si Mn Cr Mo Ni Co Nb Ti Al Cu Fe W Others

Alloy 625 0.008 0.025 0.08 0.01 22.19 8.84 64.40 -/- 3.60 0.166 0.130 0.004 0.359 -/- 0.005

Alloy 50/650

0.005 0.111 0.09 0.380 19.55 11.55 51.60 0.750 0.24 0.010 -/- 0.11 --- 1.60 0.011

Alloy (650)

Nimo T

0.011 0.039 0.05 0.06 21.68 9.98 64.58 <0.03 <0.03 0.12 0.05 <0.03 0.72 2.58 -/-

Alloy 686 <0.010 -/- 0.02 0.22 20.41 16.26 58.52 -/- -/- 0.06 0.20 0.01 0.36 3.94 <0.50

Alloy G30 0.01 n.a. 0.18 1.11 29.00 5.16 Bal. 3.69 n.a. -/- -/- 1.96 14.81 2.90 0.94

Alloy C22 0.005 0.0210 0.050 -/- 22.50 13.650 58.13 0.01 0.01 0.010 0.210 0,02 2.13 2.8800 0.179

Alloy 70K 0.040 0.033 1.26 0.29 29.50 <0.01 68.40 0.01 <0.010 <0.010 0.160 0.02 0.10 n.a. 0.006

Bal.*

n.a. not analysed-/- not specified* Iron in balance, approx. 14 wt.-% as listed in the previous slide

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Fluegas Side Condition after 8,000 h Service (After Removal of Salt-Ash-Deposits)

Alloy 686 W.-Nr. 2.4606

Analysis: Cr 18 Mo 15 Ni 54 W 4 Fe 9

Alloy 625 W.-Nr. 2.4831

Analysis: Cr 21 Mo 8 Ni 62 W -/- Fe 4 Nb 4

Alloy G30 W.-Nr. 2.4603

Analysis: Cr 28 Mo 5 Ni 38 W 3 Fe 20 Nb 1

Alloy 50/650 W.-Nr. 2.4850


Alloy (650) Nimo T W.-Nr. -/-


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Steam Side Condition after 8,000 h Service Estimated Temperatures in the Deposits on the Flue Gas Side

inner oxide layer

outer oxide layer

carbon steel - 15Mo3

raisin / steam

approx. 40 µm (up to 50 µm)

Finding: steam side with approx. 40 µm inner oxide layer= degradation of approx. 0,03 to 0,04 mm per year of service

Calculation (based on 10 CrMo 9-10): approx. 550-560°C surface temperature at steam side

Estimation for temperature level in the deposits: - at material surface: approx. 580-600°C - at fluegas side: approx. 630-..?..°C

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Alloy G30 - Welding vs. Specification

Swarf Si Mn Cr Mo Ni Nb Ti Al Co Cu Fe W Total

017-3-1 0.1 1.0 26.6 4.3 37.5 0.5 --- 0.2 3.3 1.7 21.7 3.0 100.0 017-3-2 --- 1.1 27.9 4.8 37.9 0.7 --- 0.3 3.2 1.7 19.2 3.1 100.0 017-3-3 0.1 1.2 27.6 4.6 37.9 0.7 --- 0.2 3.4 1.7 19.7 2.8 100.0 017-3-4 0.1 1.2 27.6 4.8 38.3 0.9 --- 0.2 3.3 1.7 19.0 2.9 100.0 017-3-5 --- 1.2 27.2 4.5 37.7 0.8 --- 0.2 3.3 1.6 20.4 3.0 100.0 017-4-1 --- 1.1 27.1 4.3 38.6 0.5 --- 0.1 3.5 1.7 20.1 2.9 100.0 017-4-2 --- 1.2 27.2 4.5 38.0 0.6 --- 0.2 3.3 1.8 20.4 2.9 100.0 017-4-3 --- 1.1 28.1 4.5 38.5 0.6 --- 0.2 3.5 1.7 18.6 3.2 100.0 017-4-4 --- 1.2 28.4 4.9 38.6 0.7 --- 0.2 3.4 1.8 17.6 3.1 100.0 017-4-5 --- 1.0 27.0 4.4 37.7 0.6 --- 0.2 3.3 1.6 21.3 2.8 100.0

Min. 1.0 26.6 4.3 37.5 0.5 3.2 1.6 17.6 2.8 100.0 Mean 1.1 27.5 4.6 38.1 0.7 3.4 1.7 19.8 3.0 100.0 Max. 1.2 28.4 4.9 38.6 0.9 3.5 1.8 21.7 3.2 100.0

Specif. 0.2 1.1 29.0 5.2 Bal. -/- -/- -/- 3.7 2.0 14.8 2.9 Dilution 10.6 Legend: Mean: Meanvalue of analysis of the clad, approx. 1 - 1.5 mm above base material

Specif.: Specification of material test report for the filler metalDilution: Analysed on the fresh welded clad

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Alloy G30 - Corrosion Mechanisms

Saltmeltcorrosion

Width 0,7 mm

Saltmeltcorrosion

Width 0.7 mm

Saltmeltcorrosion

Width 0.7 mm

Alloy G30 W.-Nr. 2.4603


Saltmelts precisely attack along thethread-like overlap of the spiral welded bead

Morphology: one pit next to the other pit;each pit was formed by saltmeltcorrosion(degradation regardless the microtextures)

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Alloy 625 - Welding vs. Specification


018-3-1 0.1 --- 21.0 8.7 61.6 3.9 0.2 0.1 --- --- 4.2 0.2 100.0 018-3-2 0.1 --- 20.9 8.4 61.7 3.7 0.2 0.1 --- --- 4.7 0.2 100.0 018-3-3 0.1 --- 20.9 8.3 62.1 3.3 0.2 0.1 --- --- 4.7 0.3 100.0 018-3-4 0.1 --- 21.4 8.3 63.6 3.0 0.1 0.1 --- --- 3.2 0.2 100.0 018-3-5 0.1 --- 21.3 8.0 62.9 3.1 0.2 0.1 --- --- 4.3 --- 100.0 018-4-1 0.1 --- 21.3 8.8 62.3 4.3 0.2 0.1 --- --- 2.7 0.2 100.0 018-4-2 0.1 --- 21.1 8.2 62.7 3.4 0.1 0.1 --- --- 4.1 0.2 100.0 018-4-3 0.1 --- 21.1 8.3 62.3 3.1 0.1 0.1 --- --- 4.7 0.2 100.0 018-4-4 0.1 --- 21.5 8.3 63.3 3.4 0.2 0.1 --- --- 2.9 0.2 100.0 018-4-5 0.1 --- 20.9 8.5 61.8 3.8 0.2 0.1 --- --- 4.4 0.3 100.0

Min. 20.9 8.0 61.6 3.0 0.1 2.7 100.0 Mean 21.1 8.4 62.4 3.5 0.2 4.0 0.2 100.0 Max. 21.5 8.8 63.6 4.3 0.2 4.7 0.3 100.0

Specif. 0.1 <0.1 22.2 8.8 64.4 3.6 0.2 0.1 -/- <0.1 0.4 -/- Dilution 3.2 Legend: Mean: Meanvalue of analysis of the clad, approx. 1 - 1.5 mm above base material


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Alloy 625 - Corrosion Mechanisms

SaltmeltcorrosionSaltmeltcorrosion, cracking

Width 0,7 mm

Saltmeltcorrosion

Width 0,7 mm

Alloy 625 W.-Nr. 2.4831


Width 0,75 mm

Each pit was formed by Saltmeltcorrosion

Dominated by saltmeltcorrosion (regardless microtextures),plus some evidence for corrosion along the dendrites

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Alloy 50/ 650 - Welding vs. Specification


014-3-1 0.1 0.4 18.9 12.4 48.2 0.5 --- 0.2 0.6 --- 17.2 1.5 100.0 014-3-2 --- 0.3 18.8 11.5 49.2 0.4 --- 0.2 0.7 0.2 17.1 1.5 100.0 014-3-3 0.1 0.4 18.4 11.1 49.6 0.4 --- 0.2 0.6 0.4 17.4 1.5 100.0 014-3-4 0.1 0.5 18.9 11.4 50.3 0.4 --- 0.2 0.8 --- 15.8 1.6 100.0 014-3-5 --- 0.4 18.9 10.8 50.5 0.3 --- 0.2 0.7 0.1 16.4 1.7 100.0 014-4-1 0.1 0.5 19.3 12.4 49.4 0.4 --- 0.2 0.7 0.2 15.3 1.5 100.0 014-4-2 0.1 0.4 18.8 11.5 49.9 0.3 --- 0.2 0.7 0.1 16.5 1.5 100.0 014-4-3 0.1 0.4 18.7 11.3 49.9 0.3 --- 0.2 0.7 --- 16.9 1.6 100.0 014-4-4 --- 0.3 18.3 10.4 51.1 0.4 --- 0.2 0.8 0.2 16.6 1.6 100.0 014-4-5 0.1 0.4 18.3 11.2 47.8 0.3 --- 0.2 0.7 0.2 19.3 1.6 100.0

Min. 0.3 18.3 10.4 47.8 0.3 0.6 15.3 1.5 100.0 Mean 0.4 18.7 11.4 49.6 0.4 0.7 0.2 16.8 1.6 100.0 Max. 0.5 19.3 12.4 51.1 0.5 0.8 0.4 19.3 1.7 100.0

Specif. 0.1 0.4 19.6 11.6 51.6 0.2 <0.1 -/- 0.8 0.1 -/- 1.6 Dilution 9.5

?!

Legend: Mean: Meanvalue of analysis of the clad, approx. 1 - 1.5 mm above base materialSpecif.: Specification of material test report for the filler metalDilution: Analysed on the fresh welded clad

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Alloy 50/ 650 - Corrosion Mechanisms

Gaseous

attack

SaltmeltSaltmeltcorrosion

Width 0.7 mm

Saltmeltcorrosion

Width 0.7 mm

Alloy 50/650 W.-Nr. 2.4850

Analyse: Cr 19 Mo 11 Ni 50 W 2 Fe 17

Width 1 mm

Each pit was formed by Saltmeltcorrosion

Some evidence for corrosion along the dendrites

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Alloy (650) Nimo T - Welding vs. Specification


016-3-1 --- 0.1 20.3 9.4 60.3 --- 0.1 0.1 --- --- 7.0 2.6 100.0 016-3-2 --- --- 20.5 9.3 62.7 --- 0.1 0.1 --- --- 4.3 3.0 100.0 016-3-3 --- 0.1 20.6 8.9 63.2 --- 0.1 0.1 --- --- 4.3 2.7 100.0 016-3-4 --- --- 20.6 8.9 63.5 --- --- 0.1 --- --- 4.0 2.9 100.0 016-3-5 --- --- 20.1 9.2 60.7 --- 0.2 0.1 --- --- 6.8 2.9 100.0 016-4-1 --- 0.1 21.1 10.4 61.2 --- 0.1 0.1 --- --- 4.2 2.7 100.0 016-4-2 --- --- 20.3 10.6 57.4 --- 0.1 0.1 --- --- 8.9 2.6 100.0 016-4-3 --- --- 20.4 8.9 62.9 --- 0.1 0.1 --- --- 4.6 3.0 100.0 016-4-4 --- 0.1 20.4 9.0 62.6 --- 0.1 0.1 --- --- 4.9 2.8 100.0 016-4-5 --- 0.1 20.2 9.0 62.3 --- 0.1 --- --- --- 5.5 2.8 100.0

Min. 20.1 8.9 57.4 4.0 2.6 100.0 Mean 20.4 9.4 61.7 5.5 2.8 100.0 Max. 21.1 10.6 63.5 8.9 3.0 100.0

Specif. <0.1 <0.1 21.7 10.0 64.6 <0.1 0.1 0.1 <0.1 <0.1 0.7 2.6 Dilution 2.8 Legend: Mean: Meanvalue of analysis of the clad, approx. 1 - 1.5 mm above base material


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Alloy (650) Nimo T - Corrosion Mechanisms

Gaseous attack

Width 0.7 mm

Saltmeltcorrosion

Width 0.7 mm

Saltmeltcorrosion

Width 0.7 mm



Saltmeltcorrosion and selective corrosion of dendrites;Indication for liquid and gaseous attack,

...but in which order?

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Alloy 686 - Welding vs. Specification


015-3-1 --- 0.2 18.8 14.6 55.4 0.2 --- 0.2 --- --- 6.8 3.8 100.0 015-3-2 --- 0.2 19.1 15.2 56.0 0.1 --- 0.2 --- --- 5.5 3.6 100.0 015-3-3 --- 0.3 18.6 13.9 54.4 0.2 --- 0.2 --- --- 8.8 3.6 100.0 015-3-4 --- 0.2 18.7 14.7 55.1 --- 0.1 0.2 --- --- 7.2 3.7 100.0 015-3-5 --- 0.3 18.5 13.6 56.2 0.1 0.1 0.2 --- --- 7.2 3.8 100.0 015-4-1 --- 0.3 18.8 15.6 53.9 0.1 --- 0.2 --- --- 7.6 3.5 100.0 015-4-2 --- 0.3 18.0 14.9 51.6 0.1 --- 0.2 --- --- 11.4 3.5 100.0 015-4-3 --- 0.3 17.7 16.7 49.3 0.2 --- 0.2 --- --- 11.9 3.6 100.0 015-4-4 --- 0.3 18.4 14.5 54.0 0.2 --- 0.2 --- --- 8.7 3.7 100.0 015-4-5 --- 0.3 17.8 13.6 53.2 0.4 --- 0.2 --- --- 11.1 3.4 100.0

Min. 17.7 13.6 49.3 5.5 3.4 100.0 Mean 0.3 18.4 14.7 53.9 0.2 8.6 3.6 100.0 Max. 19.1 16.7 56.2 0.4 11.9 3.8 100.0

Specif. <0.1 0.2 20.4 16.3 58.5 -/- <0.1 0.2 -/- <0.1 0.4 3.9 Dilution 3.6 Legend: Mean: Meanvalue of analysis of the clad, approx. 1 - 1.5 mm above base material


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Gaseous attack, cracking

Width 0.7 mm

Gasous attack

Width 0.7 mm

Occasional saltmeltcorrosion

Width 0.7 mm

Alloy 686 - Corrosion Mechanisms

Alloy 686 W.-Nr. 2.4606


Saltmeltcorrosion and selective corrosion of dendrites;Indication for liquid and gaseous attack,

...but in which order?

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Preliminary Result

Alloy 686 W.-Nr. 2.4606


Alloy 625 W.-Nr. 2.4831


Alloy G30 W.-Nr. 2.4603


Alloy 50/650 W.-Nr. 2.4850




- severely degraded in 1 year, but unbroken surface- not welded best = „degree of freedom“ for welder

destroyed by saltmeltcorrosion / high iron content

the standard material (welded best) does not work at temperatures approx. >550°C; destroyed by saltmeltcorrosion

... 6 wt.-% Molybdenum less than alloy 686

saltmeltcorrosionand gaseous attack; analysis in progress; repeat the testtogether with Alloy C22

chemin cladding for sh in wte-plant, steamside approx. 500°c chemin prewin general assembly at...

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