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EDITORIAL
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A D V A N C E D M A T E R I A L S & P R O C E S S E S | N O V E M B E R / D E C E M B E R 2 0 1 5
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iTSSe
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FEA U E ARTICLE
3. Thermal spray application
•
Inspection: Wire purity and diameter, current,
voltage, air pressure (<100 psi), DFT, adhesion bond
strength, certified applicator
•
Intervals between blasting and sealer application is
important
•
DFT (dry film thickness) of the TSA is achieved with
cross spray application with roughly 75-100
μ
m in
single spray coat
•
Maintain recommended spray width and gun distance
•
Bond strength shall average 1800-2000 psi
•
Sealer coat of Al-silicone application (theoretical
coverage of >38
μ
m)
•
Visual
General inspection and panel coating procedures are
shown in the images on the previous page. Figure 2 shows
surface profile measurement after blasting according to
ASTM D4417. As per the customer’s specification, the sur-
face profile should be more than 65
μ
m. However, the actu-
al profile was maintained on the higher side (75-90
μ
m) to
obtain better adhesion values. Figure 3 shows preparation
of the test panel (comparator) for adhesion, DFT, finish, and
porosity test (ASTM E2109), which was mandatory for every
applicator for qualification.
Look for Part II of this article in the February 2016 issue
of
iTSSe.
iTSSe
For more information:
Deepashri D. Nage is deputy general
manager, L&T Hydrocarbon Engineering Ltd., R&D Building,
Powai Campus, Gate No. 1, Saki Vihar Road, Powai, Mumbai
- 400 072 (India), +91 22 6705 2780,
deepashri_nage@lntenc. com, www.lntenc.com.
References
1. P. Ault, TheUse of Coatings for Corrosion Control onOffshore
Oil Structures,
Protect. Coatings Europe,
Vol 11(4), p 42-46, 2006.
2. I. Gedzevicius and A.V. Valiulis, Analysis of Wire Arc Spraying
Process Variables on Coatings Properties, Proceedings of the
12th International Scientific Conference Achievements in Me-
chanical and Materials Engineering, AMME, Gliwice-Zakopane,
Poland, 2003.
3. J. Bland, Corrosion Testing of Flame-Sprayed Coated Steel—A
19-Year Report, Miami, FL: AmericanWelding Society, 1974.
4. R.L. Alumbaugh and A.F. Curry, Protective Coatings for Steel
Pilings: Additional Data on Harbor Exposure of 10-ft Simu-
lated Piling, Report CEL-TR-7115, U.S. Navy Civil Engineering
Laboratory, Port Hueneme, CA, March 1978.
5. AWS C2.23M/C2.23:2003, NACE No. 12, SSPC-CS 23.00,
Specification for the Application of Thermal Spray Coatings
(Metalizing) of Aluminum, Zinc and Their Alloys and Compos-
ites for the Corrosion Protection of Steel.
Automated & Robotic Blasting Systems 800-228-7894 Toll-Free, U.S. & Canada E-mail: ampinfo@guyson.com guyson.com WHERE QUALITY COMES TO THE SURFACE 4 Surface prep for coatings 4 Metallurgical shot peening 4 Nondestructive blast cleaningGuyson_AMP_halfpg_4c.indd 1
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