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S. Papaefthymiou
and/or hydrogen-induced cracking (HIC) in the pipeline steel leading to its premature
failure accompanied by great environmental and financial risks.
Microstructure and metallurgical characteristics of the applied pipeline steel and
the weld are of paramount importance for the structural integrity of the pipeline under
extreme conditions. Furthermore, pipeline steels nowadays operate in deep/ultradeep seas and arctic environments. These operational conditions dictate the limits
for modern pipelines and for the utilized pipeline steel grades. Thus, in addition to
the seismic, the geological, and the all kind of strength and strain operational conditions, including all kind of operations for laying out the pipeline in the seabed (from
shallow to deep-sea waters), the extreme service conditions need to be addressed in
the pipeline design. Low temperature operations on deep/ultra-deep-sea and arctic
environments that represent extreme environments and bring the current steel compositions to their limits have urged the material development to higher toughness steel
grades. Apart from the necessity for excellent weldability, the high cleanliness and
the high strength-elongation combinations with targeted microstructures are now in
focus. Today, pipeline manufacturers need to take also the unknown into consideration. Pipeline design, steel and manufacturing requirements, the possible transport of
more corrosive mediums, and the service in even extremer environments urge steel
and pipeline manufacturers to continuous improvements through research with the
aim to match these technological and service aspects.
According to U.S. Energy Information Administration [1], the main source of
energy will still be fossil fuels. It is expected that the consumption of petroleum
will be decreased from 32% (estimated at 2018) to 27% up until 2050 while gas
consumption is expected to double until 2035. The energy security which relies
on reliable and affordable access to energy sources was greatly supported by the
construction of thousands of kilometers long pipelines. In 2006, the total length of
high pressure pipelines was estimated to be 3,500,000 km worldwide from which 64%
is used for gas transportation while 19 and 17% for the transportation of petroleum
and crude oil.
12.2 Matching Tomorrow Challenges Today
12.2.1 Extreme Conditions
Modern pipelines operate under specific environments and transport mediums that
are considered extreme conditions. These relate operational and welding conditions
and the properties of the transported medium.
• Operational conditions:
Deep and ultra-deep-sea that demand higher strength steel grades to be used
reeling operation for laying out the pipeline into the seabed that demand high
strain corrosion and erosion environment that limits the phases present into the
steel’s microstructure.
S. Papaefthymiou
and/or hydrogen-induced cracking (HIC) in the pipeline steel leading to its premature
failure accompanied by great environmental and financial risks.
Microstructure and metallurgical characteristics of the applied pipeline steel and
the weld are of paramount importance for the structural integrity of the pipeline under
extreme conditions. Furthermore, pipeline steels nowadays operate in deep/ultradeep seas and arctic environments. These operational conditions dictate the limits
for modern pipelines and for the utilized pipeline steel grades. Thus, in addition to
the seismic, the geological, and the all kind of strength and strain operational conditions, including all kind of operations for laying out the pipeline in the seabed (from
shallow to deep-sea waters), the extreme service conditions need to be addressed in
the pipeline design. Low temperature operations on deep/ultra-deep-sea and arctic
environments that represent extreme environments and bring the current steel compositions to their limits have urged the material development to higher toughness steel
grades. Apart from the necessity for excellent weldability, the high cleanliness and
the high strength-elongation combinations with targeted microstructures are now in
focus. Today, pipeline manufacturers need to take also the unknown into consideration. Pipeline design, steel and manufacturing requirements, the possible transport of
more corrosive mediums, and the service in even extremer environments urge steel
and pipeline manufacturers to continuous improvements through research with the
aim to match these technological and service aspects.
According to U.S. Energy Information Administration [1], the main source of
energy will still be fossil fuels. It is expected that the consumption of petroleum
will be decreased from 32% (estimated at 2018) to 27% up until 2050 while gas
consumption is expected to double until 2035. The energy security which relies
on reliable and affordable access to energy sources was greatly supported by the
construction of thousands of kilometers long pipelines. In 2006, the total length of
high pressure pipelines was estimated to be 3,500,000 km worldwide from which 64%
is used for gas transportation while 19 and 17% for the transportation of petroleum
and crude oil.
12.2 Matching Tomorrow Challenges Today
12.2.1 Extreme Conditions
Modern pipelines operate under specific environments and transport mediums that
are considered extreme conditions. These relate operational and welding conditions
and the properties of the transported medium.
• Operational conditions:
Deep and ultra-deep-sea that demand higher strength steel grades to be used
reeling operation for laying out the pipeline into the seabed that demand high
strain corrosion and erosion environment that limits the phases present into the
steel’s microstructure.