Menu
Search
Filters
Close
Menu

02384 LONG TERM TESTING OF PROTECTIVE COATINGS AND WELD OVERLAYS IN A SUPERCRITICAL BOILER, RETROFITTED WITH LOW NOx BURNERS

Picture for 02384 LONG TERM TESTING OF PROTECTIVE COATINGS...
Available for download
Product Number: 51300-02384-SG
ISBN: 02384 2002 CP
Author: W.T. Bakker, J.L. Blough, S.C. Kung, T.L. Banfield, and P. Cunningham
$0.00
$20.00
$20.00
From 1994-1999 several protective coatings and weld overlays were evaluated in Hatfield's Ferry #2 boiler. This boiler is a universal pressure, once through, supercritical boiler rated at 550 MWe. It burns eastern bituminous coals with a sulfur content of about 2.2%. Prior to the tests the boiler was retrofitted with a low NOx cell burner system (LNCB). During the first round of the testing mainly thermal spray coatings were tested, as expected corrosion rates were relatively low (<25 mils (0.62 mm)/yr). This expectation was based on laboratory corrosion testing as well as results from field testing in the first boiler retrofitted with a low NOx cell burner system. However, corrosion rates were found to be at least 2-3 times higher than expected and the thermal spray coating provided inadequate protection. Thus a second panel containing weld overlays, and diffusion coatings in addition to the most promising thermal spray coatings was installed and tested for 2.5 yrs. Evaluation of the coatings and weld overlays confirmed that the durability of the thermal spray and diffusion coatings was generally inadequate in the most corrosive areas. Further testing is needed to confirm their suitability for less corrosive areas, although some promising results were obtained. The durability of weld overlays depended greatly on their chemical composition, but all showed measurable wear. Weld overlays with a Cr content less than 20% generally corroded quite rapidly. Weld overlays with Cr content above 20% had generally low corrosion rates. The best performing materials had projected life expectancies 2-3 times greater than that of the poorest performing material. Keywords: Fireside corrosion, sulfidation, thermal spray coatings, weld overlays, low alloy steels, boiler deposits, iron sulfide.
From 1994-1999 several protective coatings and weld overlays were evaluated in Hatfield's Ferry #2 boiler. This boiler is a universal pressure, once through, supercritical boiler rated at 550 MWe. It burns eastern bituminous coals with a sulfur content of about 2.2%. Prior to the tests the boiler was retrofitted with a low NOx cell burner system (LNCB). During the first round of the testing mainly thermal spray coatings were tested, as expected corrosion rates were relatively low (<25 mils (0.62 mm)/yr). This expectation was based on laboratory corrosion testing as well as results from field testing in the first boiler retrofitted with a low NOx cell burner system. However, corrosion rates were found to be at least 2-3 times higher than expected and the thermal spray coating provided inadequate protection. Thus a second panel containing weld overlays, and diffusion coatings in addition to the most promising thermal spray coatings was installed and tested for 2.5 yrs. Evaluation of the coatings and weld overlays confirmed that the durability of the thermal spray and diffusion coatings was generally inadequate in the most corrosive areas. Further testing is needed to confirm their suitability for less corrosive areas, although some promising results were obtained. The durability of weld overlays depended greatly on their chemical composition, but all showed measurable wear. Weld overlays with a Cr content less than 20% generally corroded quite rapidly. Weld overlays with Cr content above 20% had generally low corrosion rates. The best performing materials had projected life expectancies 2-3 times greater than that of the poorest performing material. Keywords: Fireside corrosion, sulfidation, thermal spray coatings, weld overlays, low alloy steels, boiler deposits, iron sulfide.
PRICE BREAKS - The more you buy, the more you save
Quantity
1+
5+
Price
$20.00
$20.00
Product tags
Also Purchased
Picture for 06458 UNDER-DEPOSIT CORROSION MECHANISMS IN
Available for download

06458 UNDER-DEPOSIT CORROSION MECHANISMS IN BOILERS

Product Number: 51300-06458-SG
ISBN: 06458 2006 CP
Author: A.G. Howell
$20.00

Under-deposit corrosion is a common mode of failure in boiler tubes. Mechanisms include phosphate attack, caustic gouging, hydrogen damage, and wall thinning due to metal loss. Many aspects of these mechanisms and their mitigation are well-understood, while certain specific details remain uncertain or subject to controversy.

 
Picture for 04517 An Experience with Detection and Assessment
Available for download

04517 An Experience with Detection and Assessment of SAC in a Recovery Boiler

Product Number: 51300-04517-SG
ISBN: 04517 2004 CP
Author: Steven J. Pawel, Adam W. Willoughby, and Hu F. Longmire, Oak Ridge National Laboratory; Preet Mohind
$20.00
Picture for Environmental Assisted Cracking (EAC) of Steel Pressure Vessel In Boiler Water Service: Case Histori
Available for download

51315-5431-Environmental Assisted Cracking (EAC) of Steel Pressure Vessel In Boiler Water Service: Case Histories Damage Mechanism Considerations, Design, and Fabrication

Product Number: 51315-5431-SG
ISBN: 5431 2015 CP
Author: Marco De Marco
Publication Date: 2015
$20.00
Categories
Industry
Recently viewed
Popular tags
View all

Association for Materials Protection and Performance

© AMPP All Rights Reserved.
Membership Terms of Content Use
Contact Customer Support