TY  - JOUR
AU  - Arsić, Miodrag
AU  - Bošnjak, Srđan
AU  - Sedmak, Simon
AU  - Vistać, Brane
AU  - Savić, Zoran
PY  - 2019
UR  - http://rims.institutims.rs/handle/123456789/361
AB  - During the revitalization of the hydroelectric generating station A4 at the hydro power plant 'Djerdap 1', all of its parts are subjected to non-destructive testing. Cracks are detected in cast part of generator rotor hub, in the flange area toward the turbine shaft. Cracks were 10-500 mm long (determined by magnetic particle tests) and 60-100 mm deep (ultrasonic tests). The generator rotor hub is made of cast steel 25L, in accordance with the standard 977-75. The welding/surface welding repair technology in the detected crack zones of the cast part of generator rotor hub includes a large number of details, due to the structural solution and generator rotor function in service. It was also necessary to provide the carefully undertaken activities in order to enable safe operation and continuous use of the rotor hub. Failing to notice, underestimation or incorrect perception of important details could cause significant problems in hydroelectric generating station operation. The paper, due to specifics of reparation technology, contains arranged preparatory activities for the procedure apart from the welding/surface welding technology. It is of importance to mention a huge amount of money savings, The manufacture of a new generator rotor would cost over 4 million EUR (generator mass is over 300 tonnes), not taking into account the time needed for its making (6-12 months), which is directly related to the amount of energy a hydroelectric generating station can produce during that period. This technology of repair welding is also applicable for other components and structures of the turbine and the hydromechanical equipment subjected to various causes of damage during exploitation.
PB  - Institut za ispitivanje materijala, Beograd
T2  - Structural Integrity and Life
T1  - Repair of cracks detected in cast components of vertical Kaplan turbine rotor hub
EP  - 250
IS  - 3
SP  - 243
VL  - 19
UR  - https://hdl.handle.net/21.15107/rcub_rims_361
ER  - 

@article{
author = "Arsić, Miodrag and Bošnjak, Srđan and Sedmak, Simon and Vistać, Brane and Savić, Zoran",
year = "2019",
abstract = "During the revitalization of the hydroelectric generating station A4 at the hydro power plant 'Djerdap 1', all of its parts are subjected to non-destructive testing. Cracks are detected in cast part of generator rotor hub, in the flange area toward the turbine shaft. Cracks were 10-500 mm long (determined by magnetic particle tests) and 60-100 mm deep (ultrasonic tests). The generator rotor hub is made of cast steel 25L, in accordance with the standard 977-75. The welding/surface welding repair technology in the detected crack zones of the cast part of generator rotor hub includes a large number of details, due to the structural solution and generator rotor function in service. It was also necessary to provide the carefully undertaken activities in order to enable safe operation and continuous use of the rotor hub. Failing to notice, underestimation or incorrect perception of important details could cause significant problems in hydroelectric generating station operation. The paper, due to specifics of reparation technology, contains arranged preparatory activities for the procedure apart from the welding/surface welding technology. It is of importance to mention a huge amount of money savings, The manufacture of a new generator rotor would cost over 4 million EUR (generator mass is over 300 tonnes), not taking into account the time needed for its making (6-12 months), which is directly related to the amount of energy a hydroelectric generating station can produce during that period. This technology of repair welding is also applicable for other components and structures of the turbine and the hydromechanical equipment subjected to various causes of damage during exploitation.",
publisher = "Institut za ispitivanje materijala, Beograd",
journal = "Structural Integrity and Life",
title = "Repair of cracks detected in cast components of vertical Kaplan turbine rotor hub",
pages = "250-243",
number = "3",
volume = "19",
url = "https://hdl.handle.net/21.15107/rcub_rims_361"
}

Arsić, M., Bošnjak, S., Sedmak, S., Vistać, B.,& Savić, Z.. (2019). Repair of cracks detected in cast components of vertical Kaplan turbine rotor hub. in Structural Integrity and Life
Institut za ispitivanje materijala, Beograd., 19(3), 243-250.
https://hdl.handle.net/21.15107/rcub_rims_361

Arsić M, Bošnjak S, Sedmak S, Vistać B, Savić Z. Repair of cracks detected in cast components of vertical Kaplan turbine rotor hub. in Structural Integrity and Life. 2019;19(3):243-250.
https://hdl.handle.net/21.15107/rcub_rims_361 .

Arsić, Miodrag, Bošnjak, Srđan, Sedmak, Simon, Vistać, Brane, Savić, Zoran, "Repair of cracks detected in cast components of vertical Kaplan turbine rotor hub" in Structural Integrity and Life, 19, no. 3 (2019):243-250,
https://hdl.handle.net/21.15107/rcub_rims_361 .

TY  - JOUR
AU  - Međo, Bojan
AU  - Arsić, Miodrag
AU  - Rakin, M.
AU  - Sedmak, Simon
AU  - Savić, Zoran
PY  - 2018
UR  - http://rims.institutims.rs/handle/123456789/343
AB  - Vital components of the beam that enable conjoint operation of two bridge cranes are braces and threaded spindle. The beam connects two bridge cranes with overall lifting capacity of 500 t (2 × 250 t) and enables their simultaneous conjoint operation during the rehabilitation or major overhaul of hydroelectric generating set equipment at the hydro power plant ‘'Djerdap 2’. Two braces are being installed instead of two hooks when this situation occurs. The threaded spindle is loaded with 500 t (5 MN), while braces are loaded with 250 t (2.5 MN) each. Integrity of structures is a relatively new scientific and engineering discipline which in a broader sense comprises condition analysis, behaviour diagnostics, service life evaluation and rehabilitation of structures, which means that beside the usual situation in which it is necessary to evaluate the integrity of a structure when a flaw is detected by means of non-destructive tests, this discipline also comprises stress condition analysis for the crackless structure, most often through the use of finite element method. This is the way to obtain precise and detailed distribution of displacements, deformations and stresses, which enables determination of weak spots on the structure, even before crack initiation. Non-destructive tests are performed in order to analyse the current condition of braces and the threaded spindle. On the basis of performed analytical calculations it is determined that the integrity is not threatened, although some internal non-homogeneities are detected by ultrasonic testing.
PB  - Institut za ispitivanje materijala, Beograd
T2  - Structural Integrity and Life
T1  - Integrity assessment of vital beam components that enable conjoint operation of two bridge cranes
EP  - 59
IS  - 1
SP  - 53
VL  - 18
UR  - https://hdl.handle.net/21.15107/rcub_technorep_3791
ER  - 

@article{
author = "Međo, Bojan and Arsić, Miodrag and Rakin, M. and Sedmak, Simon and Savić, Zoran",
year = "2018",
abstract = "Vital components of the beam that enable conjoint operation of two bridge cranes are braces and threaded spindle. The beam connects two bridge cranes with overall lifting capacity of 500 t (2 × 250 t) and enables their simultaneous conjoint operation during the rehabilitation or major overhaul of hydroelectric generating set equipment at the hydro power plant ‘'Djerdap 2’. Two braces are being installed instead of two hooks when this situation occurs. The threaded spindle is loaded with 500 t (5 MN), while braces are loaded with 250 t (2.5 MN) each. Integrity of structures is a relatively new scientific and engineering discipline which in a broader sense comprises condition analysis, behaviour diagnostics, service life evaluation and rehabilitation of structures, which means that beside the usual situation in which it is necessary to evaluate the integrity of a structure when a flaw is detected by means of non-destructive tests, this discipline also comprises stress condition analysis for the crackless structure, most often through the use of finite element method. This is the way to obtain precise and detailed distribution of displacements, deformations and stresses, which enables determination of weak spots on the structure, even before crack initiation. Non-destructive tests are performed in order to analyse the current condition of braces and the threaded spindle. On the basis of performed analytical calculations it is determined that the integrity is not threatened, although some internal non-homogeneities are detected by ultrasonic testing.",
publisher = "Institut za ispitivanje materijala, Beograd",
journal = "Structural Integrity and Life",
title = "Integrity assessment of vital beam components that enable conjoint operation of two bridge cranes",
pages = "59-53",
number = "1",
volume = "18",
url = "https://hdl.handle.net/21.15107/rcub_technorep_3791"
}

Međo, B., Arsić, M., Rakin, M., Sedmak, S.,& Savić, Z.. (2018). Integrity assessment of vital beam components that enable conjoint operation of two bridge cranes. in Structural Integrity and Life
Institut za ispitivanje materijala, Beograd., 18(1), 53-59.
https://hdl.handle.net/21.15107/rcub_technorep_3791

Međo B, Arsić M, Rakin M, Sedmak S, Savić Z. Integrity assessment of vital beam components that enable conjoint operation of two bridge cranes. in Structural Integrity and Life. 2018;18(1):53-59.
https://hdl.handle.net/21.15107/rcub_technorep_3791 .

Međo, Bojan, Arsić, Miodrag, Rakin, M., Sedmak, Simon, Savić, Zoran, "Integrity assessment of vital beam components that enable conjoint operation of two bridge cranes" in Structural Integrity and Life, 18, no. 1 (2018):53-59,
https://hdl.handle.net/21.15107/rcub_technorep_3791 .

TY  - JOUR
AU  - Arsić, Miodrag
AU  - Malešević, Zoranka
AU  - Mladenović, Mladen
AU  - Savić, Zoran
AU  - Bošković, Goran
PY  - 2017
UR  - http://rims.institutims.rs/handle/123456789/313
AB  - Hidroelektrana Pirot, koja je izgrađena 1990 godine, je akumulaciona elektrana derivacionog tipa, koja se sastoji od dva nadzemna vertikalna agregata sa Francis turbinama nominalne snage 41,5 MW, proizvedene u Češkoj Republici, tunela i ukopanog cevovoda ukupne dužine 2030 m i prečnika od Ø 3000 mm do Ø 3500 mm. Cevovod debljine lima 22 mm je izrađen od čelika kvaliteta S275J2G3 (stara oznaka Č.0462). Maksimalni pritisak u njemu ispred turbinskog zatvarača je 2,5 MP. Cevovod je projektovan i izgrađen bez ankernih blokova na prelomima, što pretstavlja retkost u svetu. Na cevovodu se u kontinuitetu od završetka izgradnje i puštanja u rad sprovode geodetska merenja kada je cevovod prazan i neopterećen hidrostatickim pritiskom i kada je cevovod pun. Pregledom i analizom dobijenih podataka o pomeranjima duz trase cevovoda utvrđeno je da od 2003-2004 godine postoje znatno veće razlike u pomeranjima za pun i prazan cevovod, nego u prethodnom periodu. Te razlike se prvenstveno odnose na tangencijalna pomeranja za temena oznake 6, 7 i 8, koja se u odnosu na period do 2002 godine kreću od 3 mm za teme 8 do 5 mm za teme 6. Pored geodetskih merenja u kontinuitetu se, sa unutrašnje strane cevovoda, sprovode i merenja promena horizontalnih i vertikalnih prečnika. Iz tih podataka se moze videti da u periodu 2003-2004 godine postoji i značajan trend povečanja horizontalnih, kao i manje izraženo smanjenje vertikalnih prečnika. U radu je izvršena analiza trenutnog stanja i ocena integriteta cevovoda kao celine na osnovu rezultata ispitivanja vitalnog sučeonog zavarenog spoja metodama bez razaranja u zoni preloma na stacionaži - dužini cevovoda 1+263 m (vizuelno ispitivanje, ispitivanje magnetnim česticama, ispitivanje penetrantima, ispitivanje ultrazvukom, radiografsko ispitivanje, metalografsko ispitivanje metodom replika).
AB  - Hydro power plant Pirot, which was built in 1990, is an accumulation-derivative power plant, which consists of 2 above-ground vertical hydroelectric generating sets that contain Francis turbines with nominal power of 41,5 MW, manufactured in Czech Republic, a tunnel and a sunken pipeline with overall length of 2.030 m and diameter that ranges from 3.000 to 3.500 m. Pipes have been made of S275J2G3 steel. Pipe wall is 22 mm thick. Maximum pressure of 2.5 MPa occurs in front of the turbine cover. Pipeline has been designed and built without anchor blocks at curvatures, which is a rarity elsewhere. Geodetic measurements have been conducted permanently from the day the assembly was finished and pipeline was put into service, both when pipeline is empty and unloaded by hydrostatic pressure and when it is full. Analysis of obtained data regarding the movements along the pipeline route showed that from year 2003 there are significantly higher differences in movements comparing the situations when the pipeline is full and when it is empty in comparison with the previous period. Those differences primarily refer to tangential movements of vertices marked with numbers 6, 7 and 8, which, compared to the period until year 2002, are in the range from 3 mm for vertex 8 to 5 mm for vertex 6. Apart from geodetic measurements, the measurement of pipe diameter in 2 directions is also being carried out permanently. Those data show that from year 2003 the diameter in horizontal direction started to increase significantly, while at the same time the diameter in vertical direction started to decrease less significantly. This paper contains the analysis of current state and integrity evaluation of the pipeline as a whole on the basis of results of non-destructive tests performed on the vital butt-welded joint in the curvature area at chainage 1+263 m (visual testing, magnetic particle testing, penetrant testing, ultrasonic testing, radiographic testing, metallographic replication testing.
PB  - Institut IMK "14. oktobar", Kruševac
T2  - IMK-14 - Istraživanje i razvoj
T1  - Analiza trenutnog stanja i ocena integriteta cevovoda na hidroelektrani Pirot
T1  - Analysis of current state and integrity evaluation of the pipeline at hydro power plant 'Pirot'
EP  - 14
IS  - 1
SP  - 9
VL  - 23
DO  - 10.5937/IMK1701009A
ER  - 

@article{
author = "Arsić, Miodrag and Malešević, Zoranka and Mladenović, Mladen and Savić, Zoran and Bošković, Goran",
year = "2017",
abstract = "Hidroelektrana Pirot, koja je izgrađena 1990 godine, je akumulaciona elektrana derivacionog tipa, koja se sastoji od dva nadzemna vertikalna agregata sa Francis turbinama nominalne snage 41,5 MW, proizvedene u Češkoj Republici, tunela i ukopanog cevovoda ukupne dužine 2030 m i prečnika od Ø 3000 mm do Ø 3500 mm. Cevovod debljine lima 22 mm je izrađen od čelika kvaliteta S275J2G3 (stara oznaka Č.0462). Maksimalni pritisak u njemu ispred turbinskog zatvarača je 2,5 MP. Cevovod je projektovan i izgrađen bez ankernih blokova na prelomima, što pretstavlja retkost u svetu. Na cevovodu se u kontinuitetu od završetka izgradnje i puštanja u rad sprovode geodetska merenja kada je cevovod prazan i neopterećen hidrostatickim pritiskom i kada je cevovod pun. Pregledom i analizom dobijenih podataka o pomeranjima duz trase cevovoda utvrđeno je da od 2003-2004 godine postoje znatno veće razlike u pomeranjima za pun i prazan cevovod, nego u prethodnom periodu. Te razlike se prvenstveno odnose na tangencijalna pomeranja za temena oznake 6, 7 i 8, koja se u odnosu na period do 2002 godine kreću od 3 mm za teme 8 do 5 mm za teme 6. Pored geodetskih merenja u kontinuitetu se, sa unutrašnje strane cevovoda, sprovode i merenja promena horizontalnih i vertikalnih prečnika. Iz tih podataka se moze videti da u periodu 2003-2004 godine postoji i značajan trend povečanja horizontalnih, kao i manje izraženo smanjenje vertikalnih prečnika. U radu je izvršena analiza trenutnog stanja i ocena integriteta cevovoda kao celine na osnovu rezultata ispitivanja vitalnog sučeonog zavarenog spoja metodama bez razaranja u zoni preloma na stacionaži - dužini cevovoda 1+263 m (vizuelno ispitivanje, ispitivanje magnetnim česticama, ispitivanje penetrantima, ispitivanje ultrazvukom, radiografsko ispitivanje, metalografsko ispitivanje metodom replika)., Hydro power plant Pirot, which was built in 1990, is an accumulation-derivative power plant, which consists of 2 above-ground vertical hydroelectric generating sets that contain Francis turbines with nominal power of 41,5 MW, manufactured in Czech Republic, a tunnel and a sunken pipeline with overall length of 2.030 m and diameter that ranges from 3.000 to 3.500 m. Pipes have been made of S275J2G3 steel. Pipe wall is 22 mm thick. Maximum pressure of 2.5 MPa occurs in front of the turbine cover. Pipeline has been designed and built without anchor blocks at curvatures, which is a rarity elsewhere. Geodetic measurements have been conducted permanently from the day the assembly was finished and pipeline was put into service, both when pipeline is empty and unloaded by hydrostatic pressure and when it is full. Analysis of obtained data regarding the movements along the pipeline route showed that from year 2003 there are significantly higher differences in movements comparing the situations when the pipeline is full and when it is empty in comparison with the previous period. Those differences primarily refer to tangential movements of vertices marked with numbers 6, 7 and 8, which, compared to the period until year 2002, are in the range from 3 mm for vertex 8 to 5 mm for vertex 6. Apart from geodetic measurements, the measurement of pipe diameter in 2 directions is also being carried out permanently. Those data show that from year 2003 the diameter in horizontal direction started to increase significantly, while at the same time the diameter in vertical direction started to decrease less significantly. This paper contains the analysis of current state and integrity evaluation of the pipeline as a whole on the basis of results of non-destructive tests performed on the vital butt-welded joint in the curvature area at chainage 1+263 m (visual testing, magnetic particle testing, penetrant testing, ultrasonic testing, radiographic testing, metallographic replication testing.",
publisher = "Institut IMK "14. oktobar", Kruševac",
journal = "IMK-14 - Istraživanje i razvoj",
title = "Analiza trenutnog stanja i ocena integriteta cevovoda na hidroelektrani Pirot, Analysis of current state and integrity evaluation of the pipeline at hydro power plant 'Pirot'",
pages = "14-9",
number = "1",
volume = "23",
doi = "10.5937/IMK1701009A"
}

Arsić, M., Malešević, Z., Mladenović, M., Savić, Z.,& Bošković, G.. (2017). Analiza trenutnog stanja i ocena integriteta cevovoda na hidroelektrani Pirot. in IMK-14 - Istraživanje i razvoj
Institut IMK "14. oktobar", Kruševac., 23(1), 9-14.
https://doi.org/10.5937/IMK1701009A

Arsić M, Malešević Z, Mladenović M, Savić Z, Bošković G. Analiza trenutnog stanja i ocena integriteta cevovoda na hidroelektrani Pirot. in IMK-14 - Istraživanje i razvoj. 2017;23(1):9-14.
doi:10.5937/IMK1701009A .

Arsić, Miodrag, Malešević, Zoranka, Mladenović, Mladen, Savić, Zoran, Bošković, Goran, "Analiza trenutnog stanja i ocena integriteta cevovoda na hidroelektrani Pirot" in IMK-14 - Istraživanje i razvoj, 23, no. 1 (2017):9-14,
https://doi.org/10.5937/IMK1701009A . .

TY  - JOUR
AU  - Dimić, Ivana
AU  - Arsić, Miodrag
AU  - Međo, Bojan
AU  - Stefanović, Ana
AU  - Grabulov, Vencislav
AU  - Rakin, Marko
PY  - 2013
UR  - http://rims.institutims.rs/handle/123456789/202
AB  - Since local defects reduce the load-carrying capacity and deformation ability of a piping system, an analysis is undertaken to quantify the influence of weld defects on integrity of the pipe elbows subjected to internal pressure. Incompletely filled groove is examined, because this type of defect was previously detected by ultrasonic measurement on the inner surface of the pipeline from a hydro-power plant. Three-dimensional finite element analysis is conducted using Abaqus software package. The influence of weld defect geometry (its depth, length and location) on the elbow integrity is determined. Additionally, decrease of load carrying capacity is determined for the case when a crack has initiated at the bottom of the defect. The influence of finite element type (hexahedral or tetrahedral) is examined.
PB  - Faculty of Mechanical Engineering in Slavonski Brod, Faculty of Electrical Engineering in Osijek, Faculty of Civil Engineering in Osijek
T2  - Tehnički vjesnik
T1  - Effect of welded joint imperfection on the integrity of pipe elbows subjected to internal pressure
EP  - 290
IS  - 2
SP  - 285
VL  - 20
UR  - https://hdl.handle.net/21.15107/rcub_technorep_2515
ER  - 

@article{
author = "Dimić, Ivana and Arsić, Miodrag and Međo, Bojan and Stefanović, Ana and Grabulov, Vencislav and Rakin, Marko",
year = "2013",
abstract = "Since local defects reduce the load-carrying capacity and deformation ability of a piping system, an analysis is undertaken to quantify the influence of weld defects on integrity of the pipe elbows subjected to internal pressure. Incompletely filled groove is examined, because this type of defect was previously detected by ultrasonic measurement on the inner surface of the pipeline from a hydro-power plant. Three-dimensional finite element analysis is conducted using Abaqus software package. The influence of weld defect geometry (its depth, length and location) on the elbow integrity is determined. Additionally, decrease of load carrying capacity is determined for the case when a crack has initiated at the bottom of the defect. The influence of finite element type (hexahedral or tetrahedral) is examined.",
publisher = "Faculty of Mechanical Engineering in Slavonski Brod, Faculty of Electrical Engineering in Osijek, Faculty of Civil Engineering in Osijek",
journal = "Tehnički vjesnik",
title = "Effect of welded joint imperfection on the integrity of pipe elbows subjected to internal pressure",
pages = "290-285",
number = "2",
volume = "20",
url = "https://hdl.handle.net/21.15107/rcub_technorep_2515"
}

Dimić, I., Arsić, M., Međo, B., Stefanović, A., Grabulov, V.,& Rakin, M.. (2013). Effect of welded joint imperfection on the integrity of pipe elbows subjected to internal pressure. in Tehnički vjesnik
Faculty of Mechanical Engineering in Slavonski Brod, Faculty of Electrical Engineering in Osijek, Faculty of Civil Engineering in Osijek., 20(2), 285-290.
https://hdl.handle.net/21.15107/rcub_technorep_2515

Dimić I, Arsić M, Međo B, Stefanović A, Grabulov V, Rakin M. Effect of welded joint imperfection on the integrity of pipe elbows subjected to internal pressure. in Tehnički vjesnik. 2013;20(2):285-290.
https://hdl.handle.net/21.15107/rcub_technorep_2515 .

Dimić, Ivana, Arsić, Miodrag, Međo, Bojan, Stefanović, Ana, Grabulov, Vencislav, Rakin, Marko, "Effect of welded joint imperfection on the integrity of pipe elbows subjected to internal pressure" in Tehnički vjesnik, 20, no. 2 (2013):285-290,
https://hdl.handle.net/21.15107/rcub_technorep_2515 .

TY  - CONF
AU  - Arsić, Miodrag
AU  - Odanović, Zoran
AU  - Bošnjak, Srđan
AU  - Mladenović, Mladen
AU  - Savić, Zoran
PY  - 2013
UR  - http://rims.institutims.rs/handle/123456789/209
AB  - During the refurbishment of the hydroelectric generating set A6 on HPP "Djerdap 1", for the state analysis and assessment of the level and causes of degradation of the structure of the vertical Kaplan turbine runner guide vane apparatus non-destructive tests and inspections, as well as destructive tests of base material and welded joints, have been carried out after 40 years of service. Results of non-destructive tests performed on welded joints are presented in this paper (magnetic particle and ultrasonic inspection), as well as results of destructive tests of the base material and welded joints (testing of tensile properties, impact testing, metallographic analyses of the structure). A large number of crack type line indications were detected by magnetic particle inspections, while the occurrence of partial penetration in roots of welded joints was detected by ultrasonic inspections, as well as lamellar tearing of the base material. Tensile properties of tested samples taken in longitudinal and transverse direction fulfilled the requirements of the standard with certain deviations, which does not stand for samples taken in z-direction with significantly lower values of contraction of the cross-section than minimum prescribed values, which proves that base material is not resistant to the occurrence of lamellar cracks. Metallographic tests performed on specimens taken from the base material in longitudinal and transverse direction showed that the microstructure is stripe-shaped and ferrite-pearlite with non-metallic inclusions of oxide, sulphide, silicate and aluminate type, while metallographic tests performed on specimens taken from welded joints showed that their microstructure is stripe-shaped and ferrite-pearlite with non-metallic inclusions of oxide type. A large number of micro- and macro-cracks were detected in the microstructure as well. Experimental tests enabled the determination of the causes of occurrence of lamellar tearing in base material and crack type defects in welded joints, while analytical calculation that refers to the stress state enabled integrity of welded structure of the upper ring of the turbine runner guide vane apparatus.
PB  - Trans Tech Publications Ltd, Durnten-Zurich
C3  - Structural Integrity of Welded Structures
T1  - State Analysis and Integrity of Welded Structures of the Upper Ring of the Turbine Runner Guide Vane Apparatus of Hydroelectric Generating Set A6 on Hydro Power Plant Djerdap 1
EP  - +
SP  - 7
VL  - 814
DO  - 10.4028/www.scientific.net/AMR.814.7
ER  - 

@conference{
author = "Arsić, Miodrag and Odanović, Zoran and Bošnjak, Srđan and Mladenović, Mladen and Savić, Zoran",
year = "2013",
abstract = "During the refurbishment of the hydroelectric generating set A6 on HPP "Djerdap 1", for the state analysis and assessment of the level and causes of degradation of the structure of the vertical Kaplan turbine runner guide vane apparatus non-destructive tests and inspections, as well as destructive tests of base material and welded joints, have been carried out after 40 years of service. Results of non-destructive tests performed on welded joints are presented in this paper (magnetic particle and ultrasonic inspection), as well as results of destructive tests of the base material and welded joints (testing of tensile properties, impact testing, metallographic analyses of the structure). A large number of crack type line indications were detected by magnetic particle inspections, while the occurrence of partial penetration in roots of welded joints was detected by ultrasonic inspections, as well as lamellar tearing of the base material. Tensile properties of tested samples taken in longitudinal and transverse direction fulfilled the requirements of the standard with certain deviations, which does not stand for samples taken in z-direction with significantly lower values of contraction of the cross-section than minimum prescribed values, which proves that base material is not resistant to the occurrence of lamellar cracks. Metallographic tests performed on specimens taken from the base material in longitudinal and transverse direction showed that the microstructure is stripe-shaped and ferrite-pearlite with non-metallic inclusions of oxide, sulphide, silicate and aluminate type, while metallographic tests performed on specimens taken from welded joints showed that their microstructure is stripe-shaped and ferrite-pearlite with non-metallic inclusions of oxide type. A large number of micro- and macro-cracks were detected in the microstructure as well. Experimental tests enabled the determination of the causes of occurrence of lamellar tearing in base material and crack type defects in welded joints, while analytical calculation that refers to the stress state enabled integrity of welded structure of the upper ring of the turbine runner guide vane apparatus.",
publisher = "Trans Tech Publications Ltd, Durnten-Zurich",
journal = "Structural Integrity of Welded Structures",
title = "State Analysis and Integrity of Welded Structures of the Upper Ring of the Turbine Runner Guide Vane Apparatus of Hydroelectric Generating Set A6 on Hydro Power Plant Djerdap 1",
pages = "+-7",
volume = "814",
doi = "10.4028/www.scientific.net/AMR.814.7"
}

Arsić, M., Odanović, Z., Bošnjak, S., Mladenović, M.,& Savić, Z.. (2013). State Analysis and Integrity of Welded Structures of the Upper Ring of the Turbine Runner Guide Vane Apparatus of Hydroelectric Generating Set A6 on Hydro Power Plant Djerdap 1. in Structural Integrity of Welded Structures
Trans Tech Publications Ltd, Durnten-Zurich., 814, 7-+.
https://doi.org/10.4028/www.scientific.net/AMR.814.7

Arsić M, Odanović Z, Bošnjak S, Mladenović M, Savić Z. State Analysis and Integrity of Welded Structures of the Upper Ring of the Turbine Runner Guide Vane Apparatus of Hydroelectric Generating Set A6 on Hydro Power Plant Djerdap 1. in Structural Integrity of Welded Structures. 2013;814:7-+.
doi:10.4028/www.scientific.net/AMR.814.7 .

Arsić, Miodrag, Odanović, Zoran, Bošnjak, Srđan, Mladenović, Mladen, Savić, Zoran, "State Analysis and Integrity of Welded Structures of the Upper Ring of the Turbine Runner Guide Vane Apparatus of Hydroelectric Generating Set A6 on Hydro Power Plant Djerdap 1" in Structural Integrity of Welded Structures, 814 (2013):7-+,
https://doi.org/10.4028/www.scientific.net/AMR.814.7 . .