Repair Welding Methodology for the Glasses of the Kaplan Turbine Runner at the Hydro Power Plant Djerdap 1

Vertical Kaplan turbines, manufactured in Russia and with nominal power of 200 MW, have been installed in 6 hydroelectric generating units at hydro power plant Djerdap 1. Hydroelectric generating sets have been designed for the service life of 40 years due to structural solutions and limited possibilities of performing periodic inspections and state analyses.During the rehabilitation of the hydroelectric generating sets, non-destructive tests were performed on all components and structures in order to complete state analysis. In this paper the damages and methodology of repair welding for damaged glasses, which are the integral part of the kinematic system of runner blades, are presented.

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Repair of Damages that Occurred on the Welded Joints at the Body of Guide Vane Apparatus Vanes of the Vertical Kaplan Turbine

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1153.1 ◽

2019 ◽

Vol 1153 ◽

pp. 1-6

Author(s):

Miodrag Arsić ◽

Srđan M. Bošnjak ◽

Vencislav Grabulov ◽

Mladen Mladenović ◽

Zoran Savić

Keyword(s):

Power Plant ◽

Welded Joints ◽

Guide Vane ◽

Cast Steel ◽

Experimental Tests ◽

The Body ◽

Root Penetration ◽

Hydro Power ◽

Kaplan Turbine ◽

Non Destructive

Vertical Kaplan turbines, with nominal power of 178 MW and manufactured in Russia, have been installed in 6 hydroelectric generating units of hydro power plant ’Djerdap 1’. Experimental tests were carried out by non-destructive methods in order to determine the turbine condition during the rehabilitation of the hydro power plant. Lack of root penetration was detected in V40 welded joints between upper and lower sleeves and bodies of guide vane apparatus vanes. Height of the lack of root penetration was in the range between 5 and 15 mm, while the allowable height of the lack of root penetration is 3 mm, according to the technical conditions. The upper sleeves were made of cast steel 25L (in accordance with GOST 977), while lower sleeves were made of steel forging St 25 (in accordance with standards GOST 1050 for chemical composition and GOST 8479 for forgings).Methodology for the repair of non-penetrated welded joints between the sleeves and body of the guide vane apparatus vane was composed taking into account the results of ultrasonic testing. By repair methodology it is necessary to, due to the structural solution and service function of guide vane apparatus vanes, specify a large number of details, consider them carefully and carry them out in order to improve safety, because if some of them get overlooked, underestimated or incorrectly perceived, significant problems in turbine operation may occur.This methodology refers solely to the repair of damaged welded joints between sleeves and bodies of guide vane apparatus vanes.

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Integrity and life estimation of turbine runner cover in a hydro power plant

Frattura ed Integrità Strutturale ◽

10.3221/igf-esis.36.07 ◽

2016 ◽

Vol 10 (36) ◽

pp. 63-68 ◽

Cited By ~ 1

Author(s):

A. Sedmak ◽

S. Bosnjak ◽

M. Arsic ◽

S.A. Sedmak ◽

Z. Savic

Keyword(s):

Power Plant ◽

Hydro Power ◽

Life Estimation ◽

Turbine Runner

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MODELING AND STUDY OF HYDROELECTRIC GENERATING SETS OF SMALL HYDRO POWER PLANTS WITH FREQUENCY-CONTROLLED PERMANENT MAGNET SYNCHRONOUS GENERATORS

ENERGETIKA Proceedings of CIS higher education institutions and power engineering associations ◽

10.21122/1029-7448-2016-59-2-106-121 ◽

2016 ◽

Vol 59 (2) ◽

pp. 106-121

Author(s):

R. I. Mustafayev ◽

L. G. Gasanova ◽

M. M. Musayev

Keyword(s):

Permanent Magnet ◽

Power Plants ◽

Synchronous Generators ◽

Hydro Power ◽

Permanent Magnet Synchronous Generators ◽

Generating Sets ◽

Hydro Power Plants ◽

Hydroelectric Generating Sets

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Human reliability in non-destructive inspections of nuclear power plant components: modeling and analysis

Brazilian Journal of Radiation Sciences ◽

10.15392/bjrs.v7i2b.368 ◽

2019 ◽

Vol 7 (2B) ◽

Author(s):

Vanderley Vasconcelos ◽

Wellington Antonio Soares ◽

Raissa Oliveira Marques ◽

Silvério Ferreira Silva Jr ◽

Amanda Laureano Raso

Keyword(s):

Power Plant ◽

Nuclear Power Plant ◽

Human Factors ◽

Nuclear Power ◽

Power Plants ◽

Failure Modes ◽

Cooling System ◽

Human Reliability ◽

Non Destructive ◽

Plant Components

Non-destructive inspection (NDI) is one of the key elements in ensuring quality of engineering systems and their safe use. This inspection is a very complex task, during which the inspectors have to rely on their sensory, perceptual, cognitive, and motor skills. It requires high vigilance once it is often carried out on large components, over a long period of time, and in hostile environments and restriction of workplace. A successful NDI requires careful planning, choice of appropriate NDI methods and inspection procedures, as well as qualified and trained inspection personnel. A failure of NDI to detect critical defects in safety-related components of nuclear power plants, for instance, may lead to catastrophic consequences for workers, public and environment. Therefore, ensuring that NDI is reliable and capable of detecting all critical defects is of utmost importance. Despite increased use of automation in NDI, human inspectors, and thus human factors, still play an important role in NDI reliability. Human reliability is the probability of humans conducting specific tasks with satisfactory performance. Many techniques are suitable for modeling and analyzing human reliability in NDI of nuclear power plant components, such as FMEA (Failure Modes and Effects Analysis) and THERP (Technique for Human Error Rate Prediction). An example by using qualitative and quantitative assessesments with these two techniques to improve typical NDI of pipe segments of a core cooling system of a nuclear power plant, through acting on human factors issues, is presented.

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