Methodology for Reparation of Damaged Sleeves and Welded Shield Sections of Guide Vanes at Hydropower Plant DJERDAP 1

Abstract:

Normal 0 false false false MicrosoftInternetExplorer4 Vertical Kaplan turbines, manufactured in Russia and with nominal power of 200 MW, have been installed in 6 hydroelectric generating units at ’Djerdap 1’. During the refurbishment of hydropower plant experimental non-destructive tests were performed in order to determine the state of turbine components. During the course of testing damage was detected at sleeves and welded shields of guide vanes, which occurred as a consequence of turbine shaft vibrations. 1782 mm long guide vane sleeves were made of cast steel 25L (GOST standard), 260 mm long sleeve was made of forged steel St 25 (GOST standard), while welded shields of guide vanes were made of austenitic steel 08X18H10T (GOST standard). Results of experimental tests and methodology for reparation of damaged surfaces of sleeves and welded shields of guide vanes are presented in this paper. It was necessary, due to the structural solution used for the design of guide vanes and their function during service, to define a large number of details, carefully reconsider them and carry out all activities with extreme care in order to enable the safe operation and continuous use of vanes through the use of reparation methodology for welding/surface welding of sleeves and welded shields. Overlooking, underestimation or incorrect perception of important details could cause significant problems during turbine operation. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;}

• Periodical: Advanced Materials Research (Volume 1029)
• Pages: 8-13
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1029.8
• Online since: September 2014
• Authors: Miodrag Arsić*, Brane Vistać, Srđan M. Bošnjak, Vencislav Grabulov, Zoran Savić
• Keywords: Damage Reparation, Integrity Evaluation, Strength Calculation, Supply Tank, Tests

References

[1] Documents of the manufacturer of the upper ring of vertical Kaplan turbine runner guide vane apparatus of hydroelectric generating set A6. LMZ, Sankt Peterburg, 1973.

[2] EN 970, Non-destructive examination of fusion welds - Visual examination, European Committee for Standardization, 2003.

[3] EN 571-1, Non destructive testing- Penetrant testing - Part 1: General principles, European Committee for Standardization, 2005.

[4] EN 1714, Non destructive testing of welded joints. Ultrasonic testing of welded joints, European Committee for Standardization, 2003.

DOI: 10.3403/2685547

[5] ISO 5817, Welding - Fusion-welded joints in steel, nickel, titanium and their alloys (beam welding excluded) - Quality levels for imperfections, International Institute of Welding, 2003.

DOI: 10.3403/30408358

[6] ГOСT 977, Steel Castings. General specifications, Russian Standard. 1988.

[7] ГOСT 1050, Rolled steel, calibrated, with special surface finish of quality carbon structural steel. General specifications. Russian Standard. 1988.

[8] ГОСТ 5632, High-alloy steel corrosion-resistant, heat-resistant and heat-resistant. Russian Standard. 1972.

[9] ГОСТ 8479, Forgings of structural carbon and alloy steel. General specifications. Russian Standard. 1970.

[10] ГОСТ 7350, Steel thick corrosion-resistant, heat and heat resistant. Specifications. Russian Standard. 1977.

[11] М. Arsić аnd B. Vistać, Repair technology - Guide Vane, Report nr. TZ 421114-10026-1D, Institute for Materials Testing, 2011, Belgrade.

[12] M. Arsić and B. Vistać, Repair technology - Guide Vane Sleeves, Report nr. TZ 421114-10027-1, Institute for Materials Testing, 2012, Belgrade.

[13] ЭА - 395/9, Ea electrodes for welding structures, including a charge of high strength alloy steel, welding electrodes LEZ, Russia.

[14] OK 67. 70 , Acid rutile electrode givin an over alloyed weld metal, "ESAB", Sweden.

[15] B. Vistać and M. Arsić, Technology for welding of shield at guide vanes, Report nr. TZ 421114-009-1, Institute for Materials Testing, 2013, Belgrade.