TY  - CONF
AU  - Gligorijević, Bojan R.
AU  - Katavić, Boris T.
AU  - Alil, Ana
AU  - Jegdić, Bore V.
AU  - Ristić, Marko
AU  - Prokolab, Milan
PY  - 2011
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6107
AB  - As-received floating-head heat exchanger bolts were broken (BB) and deposite-coated. The aim was to estimate
a cause of their failure. The new bolts of the same material were used as a reference material (reference bolt –
RB). After visual and radiographic examination, their chemical composition, structure and room-temperature
mechanical properties were determined and compared. Comparison was made with the values set by standard,
as well. Afterwards, fractography was performed on fractured surfaces of tensile specimens and originally
(during exploitation) BBs to try to get an impression about bolts failure mechanism. Qualitative analysis of
deposite was employed in order to confirm was there any possible influence of surroundings during their failure
in terms of corrosion-assisted cracking. Chemical composition of RB and BB materials was analyzed by use of
spectrophotometry and structure properties with light optical microscope (LOM). Fractured surfaces of tensile
specimens and of BBs, as well as deposite chemistry, were analyzed by use of Scanning Electron Microscopy
with Energy Dispersive System (SEM-EDS). BBs had an approximately three times higher sulphur content and
lesser manganese content, lower ductility and higher strength values comparing to those of the RBs. Generally,
fracture surfaces of both, RB and BB tensile specimens have a similar rosette-like macro-appearance. The only
difference is that the radial marks in the case of the RBs are rougher. The surface has a more fibrous area and
shear lip presence. Fracture mode can be characterized as dimple rupture and micromechanism as microvoid
coalescence. In the case of BB tensile specimens, the mixed presence of dimples and cleavage facets was
noticed. The macrofractography of originally broken surfaces shows a rough and complex topography of
fracture surfaces indicating on a possibility that bolts failure has been a result of complex loading conditions.
Presence of sulphur- and chlorine-containing particles on the fracture surfaces of BBs and in deposite reveals a
possibility that failure was environmentally-assisted.
PB  - Timisoara, Romania
C3  - Proceedings of the 9th International Conference “Structural integrity of welded structures”
T1  - Analysis of floating-head heat exchanger bolts failure
EP  - 9
SP  - 1
UR  - https://hdl.handle.net/21.15107/rcub_technorep_6107
ER  - 

@conference{
author = "Gligorijević, Bojan R. and Katavić, Boris T. and Alil, Ana and Jegdić, Bore V. and Ristić, Marko and Prokolab, Milan",
year = "2011",
abstract = "As-received floating-head heat exchanger bolts were broken (BB) and deposite-coated. The aim was to estimate
a cause of their failure. The new bolts of the same material were used as a reference material (reference bolt –
RB). After visual and radiographic examination, their chemical composition, structure and room-temperature
mechanical properties were determined and compared. Comparison was made with the values set by standard,
as well. Afterwards, fractography was performed on fractured surfaces of tensile specimens and originally
(during exploitation) BBs to try to get an impression about bolts failure mechanism. Qualitative analysis of
deposite was employed in order to confirm was there any possible influence of surroundings during their failure
in terms of corrosion-assisted cracking. Chemical composition of RB and BB materials was analyzed by use of
spectrophotometry and structure properties with light optical microscope (LOM). Fractured surfaces of tensile
specimens and of BBs, as well as deposite chemistry, were analyzed by use of Scanning Electron Microscopy
with Energy Dispersive System (SEM-EDS). BBs had an approximately three times higher sulphur content and
lesser manganese content, lower ductility and higher strength values comparing to those of the RBs. Generally,
fracture surfaces of both, RB and BB tensile specimens have a similar rosette-like macro-appearance. The only
difference is that the radial marks in the case of the RBs are rougher. The surface has a more fibrous area and
shear lip presence. Fracture mode can be characterized as dimple rupture and micromechanism as microvoid
coalescence. In the case of BB tensile specimens, the mixed presence of dimples and cleavage facets was
noticed. The macrofractography of originally broken surfaces shows a rough and complex topography of
fracture surfaces indicating on a possibility that bolts failure has been a result of complex loading conditions.
Presence of sulphur- and chlorine-containing particles on the fracture surfaces of BBs and in deposite reveals a
possibility that failure was environmentally-assisted.",
publisher = "Timisoara, Romania",
journal = "Proceedings of the 9th International Conference “Structural integrity of welded structures”",
title = "Analysis of floating-head heat exchanger bolts failure",
pages = "9-1",
url = "https://hdl.handle.net/21.15107/rcub_technorep_6107"
}

Gligorijević, B. R., Katavić, B. T., Alil, A., Jegdić, B. V., Ristić, M.,& Prokolab, M.. (2011). Analysis of floating-head heat exchanger bolts failure. in Proceedings of the 9th International Conference “Structural integrity of welded structures”
Timisoara, Romania., 1-9.
https://hdl.handle.net/21.15107/rcub_technorep_6107

Gligorijević BR, Katavić BT, Alil A, Jegdić BV, Ristić M, Prokolab M. Analysis of floating-head heat exchanger bolts failure. in Proceedings of the 9th International Conference “Structural integrity of welded structures”. 2011;:1-9.
https://hdl.handle.net/21.15107/rcub_technorep_6107 .

Gligorijević, Bojan R., Katavić, Boris T., Alil, Ana, Jegdić, Bore V., Ristić, Marko, Prokolab, Milan, "Analysis of floating-head heat exchanger bolts failure" in Proceedings of the 9th International Conference “Structural integrity of welded structures” (2011):1-9,
https://hdl.handle.net/21.15107/rcub_technorep_6107 .