Introduction to SACS: Structural Analysis for Offshore Engineering
Summary
TLDRThis script offers an in-depth exploration of offshore jacket structures, focusing on their design, components, and installation processes. It delves into the significance of main piles, skirt piles, and mud mats for stability, and discusses various jacket elements like diagonal braces, boat landings, and living quarters. The speaker also touches on specialized designs like tubular joints and the importance of API RP 2A in jacket construction. The script further covers transportation and installation methods, including Loadout, sea fastening, and launching, emphasizing the need for structural analysis at each stage to ensure safety and functionality.
Takeaways
- 🏗️ The main structural components of a jacket are the 'cords' or legs which support the load and are driven into the seabed for stability.
- 📍 'Skirt piles' are supplementary to the main piles, used to strengthen and consolidate the soil to increase its bearing capacity.
- 🛑 'Mud mats' are steel plates that provide temporary stability to the jacket during installation by distributing its weight over the disturbed seabed.
- 🔩 'Tubular joints' are specialized connections used in tubular structures of jackets, designed according to API RP 2A recommended practices.
- 📊 'Batter' is the angle at which jacket legs are inclined, which can be single or double, and is crucial for the structural integrity and load distribution.
- 🚀 'Launch runners' are beams that support the jacket during the launching process, where the jacket is moved from a barge into the water.
- 🚤 'Boat landing' is a platform on the jacket for the docking of supply or crew boats, designed to withstand the impact of these vessels.
- 🏢 'Cellar deck' is the lowest deck of a jacket, followed by the 'main deck' which serves as the primary functional area for operations.
- 🔧 'Conductors' and 'risers' are pipelines that transport fluids from the seabed to the topside and between platforms or to the shore, respectively.
- 🧱 'Piles' and 'pile sleeves' are foundational elements that anchor the jacket to the seabed, with grout used to secure the connection.
- 🔍 The design and operation of jackets involve various analyses, such as fabrication, loadout, transportation (C-fastening), launching, and pile driving, to ensure structural safety and functionality.
Q & A
What are the main piles in an offshore jacket structure called?
-The main piles in an offshore jacket structure are called 'cords'. They are driven through the jacket legs to support the structure.
What is the purpose of skirt piles in an offshore jacket?
-Skirt piles are used to strengthen the soil or consolidate it, providing the soil with more bearing capacity to support the load of the jacket.
Can you explain the role of mud mats in an offshore jacket structure?
-Mud mats are steel plates designed to ensure the jacket's stability on the seabed. They help prevent the jacket from floating away or moving by distributing the weight of the disturbed mud and the jacket itself.
What is a tubular joint in the context of offshore jacket structures?
-Tubular joints are specialized designs for connecting tubular structures in jackets, as per the API RP 2A code. They detail the weld thickness, shear stress, and punching shear values for the joints.
What is the difference between a single batter and a double batter in jacket design?
-A single batter refers to the jacket leg being at an angle in one direction, while a double batter means the leg is angled in two directions. The batter provides an inclination ratio, usually between 1:6 to 1:15.
What is the purpose of launch runners in jacket installation?
-Launch runners are large beams that support the jacket's weight during the launching process. They allow the jacket to be transported on a barge and then launched into the water with minimal support.
What is the function of boat landing on an offshore jacket structure?
-Boat landing is the area on the jacket structure where supply boats or crew boats can dock. It is designed to withstand the impact of boats and, in some cases, larger vessels during emergency situations.
What is a cellar deck in the context of an offshore jacket structure?
-The cellar deck is the lowest deck of an offshore jacket structure. It is typically followed by the main deck, which serves as the primary functional area for the topside operations.
What are conductors and risers in the context of offshore oil and gas extraction?
-Conductors are large lines that transport fluids from the seabed to the topside. Risers, on the other hand, are used to move fluids between platforms or from the topside to the seabed and vice versa.
What is the purpose of pile sleeves in the foundation of an offshore jacket?
-Pile sleeves are used to guide the piles into the ground during the installation process. They ensure the piles are inserted at the correct angle and position for stability.
What is the significance of grout in the construction of an offshore jacket?
-Grout, a mixture of cement, sand, and water, is used to secure the piles in place by filling the spaces between the jacket and the piles, ensuring stability and a solid connection.
Outlines
🏗️ Jacket Structure and Pile Installation
This paragraph discusses the construction of offshore jacket structures, focusing on the main piles that are driven through the jacket legs, also known as cords. It explains the need for skirt piles to strengthen the soil and increase the bearing capacity, as well as the use of mud mats to ensure stability during installation. The paragraph also touches on the design of tubular joints according to API RP 2A, which is a recommended practice for offshore structures, especially those related to oil and gas.
🔨 Jacket Design Features and Terminology
The second paragraph delves into various aspects of jacket design, including batter angles for the legs, launch runners for transportation and installation, and boat landings for access. It describes different types of decks such as the cellar deck, main deck, and living quarters, and their specific functions. The paragraph also covers the role of diagonal braces, the importance of the jacket's angle known as 'batter,' and the various components like Derrick, cranes, and production equipment that are part of the jacket structure.
🚢 Offshore Operations and Equipment
This paragraph outlines the different types of equipment and operations involved in offshore oil and gas extraction. It explains the function of conductors and risers in transporting fluids from the seabed to the topside and vice versa. The paragraph also discusses clamps, grout, flooding lines, walkways, bridges, mud mats, and J-tubes, each serving a specific purpose in the stability, operation, and maintenance of the offshore platform. Additionally, it covers the importance of adhering to relevant codes and the various loads that need to be considered in jacket design.
🔍 Fabrication and Loadout Analysis
The focus of this paragraph is on the fabrication process of jacket structures, including the construction yard activities and the analysis required to ensure the jacket's safety during this phase. It discusses the rollover process, where the structure is turned 90 degrees for assembly. The paragraph also explains the different loadout methods used to transfer the jacket from the yard to a barge, such as lifted, skidded, and trailer rollout, and the importance of conducting loadout analysis to ensure the jacket can handle the loads during these operations.
⚓ Sea Fastening and Transportation Analysis
This paragraph discusses the sea fastening process, which is crucial for securing the jacket during transportation to prevent movement and potential damage. It covers the analysis needed for transportation, taking into account the six degrees of freedom of the barge and the forces acting on the jacket. The paragraph explains the use of different fastening methods like welded connections, stanchions, lashing, and the importance of hydrodynamics in analyzing the jacket's response to wave, wind, and current conditions during transportation.
🏗️ Jacket Installation and Upending Methods
The final paragraph covers the installation process of the jacket, including launching from a barge and the methods used to upend the jacket from a horizontal to a vertical position. It describes the use of towing, launching, and the two primary upending techniques: lifting and controlled flooding. The paragraph also touches on the importance of pile driving for securing the jacket legs and the installation of topside structures on top of the jacket.
Mindmap
Keywords
💡Jacket
💡Piles
💡Mud Mats
💡Tubular Joints
💡Diagonal Braces
💡Launch Runners
💡Boat Landing
💡Cellar Deck
💡Risers
💡Loadout
Highlights
Introduction to offshore jacket structures, including main piles or 'cords' and their role in supporting the jacket.
Explanation of the eight-leg jacket and its significance in offshore structural design.
The concept of skirt piles for strengthening soil and increasing bearing capacity.
Mud mats' role in bottom stability analysis and preventing the jacket from floating away.
Tubular joints' specialized design in accordance with API codes for offshore structures.
Diagonal braces' function in connecting jacket legs at an angle, known as 'batter'.
Different types of batter in jacket design: single and double batter with their respective ratios.
Launch runners' importance in the transportation and installation of jacket structures.
Boat landings' design considerations for withstanding the impact of supply boats and emergency vessels.
Deck structures in jackets, including cellar deck, main deck, and their respective functions.
The necessity of living quarters and helidecks in standalone offshore platforms.
Differentiation between conductors and risers in fluid transportation from seabed to topside.
Use of clamps, grout, and flooding lines in maintaining the stability and position of risers.
J-tubes' role in housing control cables and power lines within the jacket structure.
Overview of the jacket design process following API RP 2A recommended practice.
Importance of fabrication analysis for ensuring the jacket's structural integrity during construction.
Loadout methods for transferring jacket structures from land to barge, including lifted, skidded, and trailer rollout.
Sea fastening analysis for securing the jacket during transportation and mitigating motion forces.
Launching methods for placing the jacket into the water, including crane lifting and controlled flooding.
Pile driving techniques for securing the jacket legs into the seabed.
Final notes on focusing on jacket-specific terminologies and operations unique to offshore structural engineering.
Transcripts
[Music]
foreign
structure the main piles are driven
right through the jacket legs or in
other words they are called cords so the
main legs of the jacket will be called
the uh cards so these are your main
links and so these main legs are called
your cords okay and this is a uh one two
three four five six seven eight this is
an eight leg jacket and uh so eight
quart jacket or an eight card jacket so
the piles will be driven right through
the legs that is the main pile so in
some conditions some soil conditions the
main piles might not be enough to the
soil might not be enough to support the
bearing capacity or the bearing load of
the jacket so in that case in order to
strengthen the jacket we need sorry to
strengthen the soil we might need to
give a couple of skirt bikes so that is
what skirt piles are given skirt piles
are given in order to strengthen the
soil or to consolidate the soil so that
more uh the soil itself will have more
of a bearing capacity uh to take the
load of the jacket so that is the skirt
piles which is given in the bottom okay
so that is the main pile and the skirt
pile so next one is the mud mats so what
happens with mudmans is usually mud mats
is basically a steel plate uh which is
given uh in in some sort of uh
Dimensions or in uh any in some in some
design design in such a way that it is
designed on the basis of something
called an on bottom stability analysis
so on bottom stability analysis is the
jacket is installed on the location at
location it is installed and before we
do the first pile driving the jacket has
to stay in location or has to stay at
location it should not be able to float
away and go or it should not be able to
float and should not be able to move so
in order for it not to move what we do
with mud mats it's a it's a steel plate
which the moment you touch the seabed a
lot of mud is Disturbed there and this
mud will be disturbed and once the
jacket is sitting on the seabed the mud
will come and rest on top of the mud map
so what happens is more weight from the
soil itself is sitting on the mud mat
and the mud mat is being supported by
the jacket so the weight of the mud
itself will be will be holding the
jacket in place along with the steel
plates okay so
basic steel plate which is having a lot
of weight and there is mud on top of it
also so that it will still change
position that
it's like a flat plate fully flat yeah
just a flat plate yes okay yeah sure
which is reinforced or which will be
connected to the jacket braces at the
bottom level okay so that is the mud
bath okay then we have skirt pre-sleeves
so these free sleeves are just for the
skirt pile we have uh sleeves through
which the uh skirt bite will be
introduced to the ground so there are
some sleeves through which because this
is a lot this is all at an angle
there'll be some sleeves from the top
and the pile will be inserted through
the sleeves so that will it will be at
the right correct angle to the soil okay
that is the skirt pile sleeves uh then
tubular joints so tubular joints is a
specific is a specialized design for
jackets especially so usually the code
that we use for jacket design is
something called API code so are you
familiar with API API yes yeah no sir
I'm not sure okay API is American
petroleum Institute so all uh offshore
codes basically most of these offshore
structure that offshore structures uh
especially related to oiling gas are
coming under the purview of API codes so
here we are going to be following API RP
be recommended practice to a that is the
code which we are using for and that is
used for official structures okay so
rp2a and within that is a specific
design called tubular design so this
tubular design is specific because in
jackets you will be mostly using tubular
structures so all the tubular structures
when they are when there is a joint
between tubular we usually have key
joints or k joints or Y joints pky
joints so there is a specific design for
tky joints and uh what is the weld
thickness or what is the shear stress or
what is the punching Shear that can be
allowed all these kind of values are
mentioned in API code so depending on
that so we have to designate all these
joints as a tubular joint and the and
there will be specific design that will
be done for all these tubular joints so
that is the tubular then we have
diagonal braces so the diagonal brace is
your normal brace between connecting two
members you have a brace uh battered
like jacket okay so this jacket's legs
or cords are supposed to be at an angle
and that angle angle is called a banner
so in offshore terms you will call those
angle a batter and there are two types
of batter there is a single batter and
there is a double back so single batter
means when the jacket like is is at an
angle to One Direction to maybe an X
direction or a y direction that is
called a single batter and if the oh
yeah yeah b a double t e r yeah and if
the jacket leg is at an angle to both
the directions then it's called a double
banded clip okay so and uh the angle the
this this inclination is provided uh in
in some sort of a ratio that ratio is
usually going to be one is to eight
sorry one is to six two one is to
Fifteen it will be in between that and
whether it is a double batter or a
single batter usually you'll have one is
to six so one is to Fifteen that will be
the usual ratio of the batter and it's
just 16 to sorry one is two one is two
one is two six two one is to Fifteen one
five okay so uh that is better then then
we have something called launch Runners
so launch Runner is something which is
related to the operation smart which is
related to transportation and
installation of a jacket so uh when we
actually do an installation job we have
different methodologies for instantly
installing a jacket so we will after
this we'll cover the operations for pni
part Transportation installation and
when we cover that we'll be going
through the different methodologies for
installation of jackets in that one of
the installation methods is called
launching it is exactly what it sounds
like you will be carrying this barge
sorry this jacket on a barge and from
the jacket from the bar you will just
launch it into the water okay and when
you do launch the support has to be
provided very minimal support has to be
provided so what we do on the jacket is
we'll just provide two beams two huge
Runners which will be just supported by
the barge and all the weight of the
jacket will be supported on these two
Runners that Runner is called a launch
Runner so we can see that details when
we cover up when pni operations we can
see the detail of that uh next is going
to be boat landing so boat landing is
basically wherever uh these jacket
structures are there up to MSL or the
mean sea level and the top side is above
that so the whenever you have a supply
boat or a crew boat which comes in they
come to the boat landing and they can
enter the jacket from the boat landing
there will be stairs to the top side so
that is where we have boat landing and
the boat landing will be designed for
taking the impact of a crew boat or a
supply boat so it will be moved to the
boat landing and in specific cases or in
in certain uh immediate requirements in
emergency situations there might be the
requirement of any other bigger ship or
a ship coming or a bigger vessel coming
and Mooring to the jacket itself and in
that case the boat landing has to be
able to take the impact of such a vessel
a dynamic impact of such a vessel also
on those jacket so the boat landing will
be designed for all these kind of loads
okay so on the okay so moving on to the
deck there are some more uh terms in the
jacket which as we go ahead we'll look
into that uh going into the deck we have
something called Cellar deck so seller
deck is going to be the most bottom most
deck and that is called a Cellar deck uh
on top of that you will have a main deck
which is going to be the main functional
deck of the top side so all these top
sides are going to be designed or are
going to be uh named because of a
certain requirement so usually we have
process platforms we have Wellhead
platforms we have a flare platform or
accommodation platform so depending on
what is the requirement that whatever is
that requirement usually happens on the
main deck so that is the main uh main
deck is used for that then you have
living quarters if it's a standalone
jacket and or a standalone platform in
which you do not have any other
complexes nearby complexes means any
other main process platforms or any
other accommodation platform nearby you
might need to have a living quarters on
board so in that case your top set will
have a living quarters and a heli deck
or a heliport oily a copter
Transportation uh then you have Derrick
Derek is usually used in a drilling
platform if you have a drilling jacket
then uh you will have to use a direct
usually nowadays we don't have a direct
on top of platforms because there is
rigs are available now drilling rigs are
available so usually we'll have drilling
rigs coming and doing the drilling not
on top sides then you have crane so so
deck crane is used for lifting supplies
from the supply vessel or for any
maintenance works on top side they need
to clean the engine head or to move a
valve from one position to another
position all these things they'll be
using the crane for that so your crane
is going to be designed for a huge
moment the moment means your supply and
your supply crane will your supply
vessel might be coming with uh two or
two to five tons of cargo and your train
has to lift it from the sea level up to
the top and maybe even from heli deck
your supply will be coming from the hell
index so it has to carry something from
the heli deck to the living quarters or
to the supply store or something like
that you will use your uh then you have
your other production equipments and
other all modules whichever your general
loads or your miscellaneous loads will
be on top of the top side so this is an
overall overall overview of the top side
and the jacket yeah yeah okay so in
jacket basically you have jacket legs uh
you have braces
joints which we just discussed and
launch Runners and trust us okay then
you have Scott files okay all other
points are all together is called
hypertenances so all your boat landing
is an opportunist uh conductors you have
conductors so conductors are the actual
flow lines or your actual lines which
will be transporting or which will be
conducting the oil or gas whatever is
your fluid from the ground to power from
the seabed to the uh top side okay so
conductor is the one which is going deep
into the seabed and it will usually be
very uh small lines or sorry usually be
big lines which will be conducting or
which will be transporting the fluid and
this will be normally your gas or your
your crude or your oil or whatever is
the fluid then you have bracing and
guides uh then you have Rises so Riser
is used for transporting or conduct or
moving your fluid from one platform to
another or one platform to a pipeline it
is used to conduct the fluid from the
top side to the ground or to the seabed
and so if you have to carry or if you
have to move this oil or gas whatever
you have uh now drilled out if you want
to move this to the onshore or you want
to move this to another platform you
need to
bring it out to bring it out you have to
go down to seabed again you have to take
it to the mud line so the that pipe
which takes it to the mud line is called
a riser and that Riser is going to be
connected to your pipeline and then this
pipeline is going to go to the next
platform and from that pipeline again
there's going to be another Riser which
will help it to go up to the top side
again so that is the use of horizon
um so whatever we are extracting from
the seabed it goes down again through
the Riser correct I mean whatever
happens in the top side happens it the
top side might be used for some sort of
a processing if it is being processed it
will be processed if it is not being
processed either way it has to be
transported somewhere so whether it is
processed or unprocessed it has to be
transported so that Transportation
happens through Riser so that's the
difference between a conductor conductor
is actually transporting it from the
seabed to the top side uh while the
Riser is doing it from the top side to
the mud line or from the mud line to the
top side either way uh then we have
clamps so clamps are used to keep the
risers in position uh grout grout is
your basic civil grout itself it's a
mixture of cement and sand and water and
flooding lines flooding lines are used
for your TNA operations when you need to
do control buoyancy of the jacket you
will be using flooding lines walkways
walkways are used for uh connection
between within the platform itself there
will be walkways for walking around and
even between connections between two
platforms bridges are will be connected
between two platforms mud mats as I
explained already mud mats are for
stability on bottom stability and then
you have J tubes which are similar to
Rices the difference being in Rices you
actually have fluid flowing through it
in J tubes you have cables or umbilicals
the cables which will be controlling the
valves or your electric power lines or
power cables and
umbilicals will be used for your valves
or for your uh plate connections or your
PSP connections all those kind of
connections we'll be using J tubes okay
okay then you have in the foundations
you will be using piles uh pile sleeves
and the grout routing is the uh
connection between the as I said the
file is inserted through the jacket
length or through the jacket cord and
the pile is connected between each other
using that that analyst between them is
connected or is grout and it is
connected with the grouting so that is
that is why we use grout there so for a
design of a jacket what we do is
basically we have to the relevant codes
are rpn2a this is what we're going to be
using okay so I'm not going into the
same principles of it because we are not
going to design the jacket as such one
more this I wanted to show you is the
offshore operations yeah so now with the
what all offshore operations are being
included in this so basically you have
when you do your jacket design or your
top side design you have different loads
that you need to consider or there are
different cases that you will be
considering so out of them the first
case is going to be your fabrication
case so in fabrication what happens and
why do you consider fabrication load
case so fabrication it is the
construction of a structure carried out
in the fabrication yard it includes
process such as cutting rolling uh
pressing fitting welding stress living
Etc so this is basically your
fabrication so what is happening in your
fabrication is this this is how your
jacket is being fabricated so basically
you have a structure which is being
constructed on the ground and once this
row is constructed on the ground you
have the other two rows also on the
sides these two rows are also
constructed on this on the side of the
main row and once this construction is
done you have to bring them together and
bringing them together is a process
called rollover so rollover means you
will turn the Row 90 degrees it can be
kept on top of the bottom row and you
will weld all this together okay so that
is called uh fabrication so what happens
in fabrication is what the reason of uh
why we are doing an eye so we need to do
an analysis here so what is the
fabrication or a yard analysis or a
fabrication analysis means uh in this
jacket structure you can see this is uh
right now the position is horizontal it
is not vertical so most of the jackets
are built like this unless it's a very
small jacket most of the jackets are
built like this so and you you can
understand that the final jacket
position is supposed to be vertical and
the load is supposed to be transferred
vertically but you can see in this
position the lacket is going to be
horizontal and the load you can see is
being transferred only on certain points
only on the location where the joints
are there so uh and the load of the
jacket or the weight of the jacket has
to be taken by these four three or four
points so to make sure that the jacket
is safe or is can be constructed in such
a way it is able to carry the load even
in this position we have to do an
analysis and make sure that the jacket
is capable or that leg or that joint is
capable of taking the load of the jacket
okay so we because talking about not
very we are talking about huge loads
here so even the smallest jackets might
be around thousand five hundred thousand
two hundred so these thousand two
hundred ton jackets should be able to
take its own weight and during the
transportation during the installation
during all this time it is going to be
in a horizontal position and the loads
are going to be distributed only in two
or three points so do during all this
time all the stresses should be taken by
the jacket without any damage so that
the final position also there is not
going to be any issue so that is the
point of doing a fabrication analysis
okay uh next is this usually these
jackets are being uh constructed or
fabricated on the uh on on something
called a keysight or a keyboard uh or on
on a yard which is very close to the to
water so the the process of transferring
this from land to the to a barge or to a
vessel is called Loadout yeah so what
happens during Loadout so there are
different forms of Loadout for uh for a
structure for top side and for a jacket
so for a jacket you have these three
kinds one is going to be lifted one is
going to be skated and one is going to
be trailer rollout so lifted Loadout
means you will just use a crane and you
can just lift it and move it onto the
bunch in the case of a very small
structure or a very small jacket because
usually even for cranes you have two
types of cranes you have offshore Crane
and an on onshore crane so usually the
yard itself most of the time you will
not have an offshore crane available you
will only have an onshore grain so the
limit or the capacity of that yard is to
do a lifted Loadout is going to be very
limited usually if the jacket structures
are very small uh is less than 500 tons
you can do some sort of lifted Loadout
or even if it's a thousand tons maybe
you can use two or three cranes and then
do the uh Loadout lifted Loadout but
usually more than that you will not be
able to use any sort of lifting because
you need an offshore crane to do the
lifting and and usually you cannot use a
offshore lift on the yard side so they
will be using some other form of Loadout
so that's a drawback of using doing a
lifted Loadout and so the other format
is going to be to do skid loader so it's
a Steeler Loadout is when you are using
a combination of skid ways or skid shoes
or Runners and they are propelled by
jacks or winches so what happens in this
case is you usually have a main beam or
a very huge Runner which is going to be
going from your onshore to the barge
which is connected to the onshore and to
the barge and you will skip it on top of
this uh beam so you will just put your
structure on top of the beam and you
just keep pulling it onto the box so in
that case you will have to use some sort
of a friction
your friction coefficient has to be very
low so that your skidding does not
damage your jacket and uh you you need a
proper winch or you need a proper uh
pulling or a pushing mechanism in which
this can be the structure can be pushed
or pulled onto the jacket sorry onto the
batch okay okay so that is your skidded
Loadout now uh trailer Loadout means you
will be using spmts spmts means self
propelled modular fans trailers
okay those are your small uh trailers
which have a number of wheels and axles
and these are the structures which you
see in this huge Refinery structure or
wind farms which are being transported
so instead of using this beam you will
load your jacket or your structure onto
these trailers so these are a couple of
you will use maybe four or five trailers
and the load will be distributed in such
a way that all these trailers will be
able to take the loads properly safely
and you will drive this spmt directly
onto the bunch and you will carry this
along with the barge okay so this is the
uh Loadout using the trailers
top sides will top sites be on the this
thing right now on the jacket right now
no no no that will be
yes everything to do with the top side
will be separate okay they will only be
meshed together made it together
offshore
so now why are we talking about Loadout
because in Loadout what happens is uh
usually same the first of all the
position is going to be horizontal so
you have a the jacket horizontally you
have to check on top of that what
happens is when you do a lifting you
have to check for lifting loads so
lifting loads means your crane your
jacket is being supported on certain pad
eyes or on trunnions
which are going to be your load points
or where there is going to be stress
concentration going to happen so if you
have a Loadout or a lifting with Just
Four Points the whole weight of the
jacket is being going to concentrate on
those four points so you have to make
sure your jacket is safe there if it's a
lifter if it's a lifting Loadout if it's
a skidded Loadout you have a beam and
you as we mentioned before you have only
two process two launch processes or two
Runners so the whole load of the jacket
is going to be on the two Runners and
you have to make sure that the two
Runners are able to take the whole load
of the jacket so that is another Loadout
analysis uh for trailer again the same
thing you have the load distribution
happening in two or three points only
and for these two or three points uh you
have to make sure that the load is being
able to carry properly also your Loadout
your spmt should be able to carry the
loads should be able to there's an axle
limit or an axle capacity for the spmts
and they should be able to sustain that
loads also yeah so this is our uh
skidded load you can see how the student
Loadout is going to happen then we have
sea fastening so C fastening is once you
have this structure loaded onto your
barge you need to see fasten it for the
transportation so this is your
transportation analysis or your
c-fasting analysis so what happens
during transportation is that your barge
will be having uh six degree of Freedom
so they have six degree of roll sorry
six degree of motions so you have your
uh
roll pitch and your and you have your uh
XYZ direction also so uh for all these
six directions you need to make sure
that your barge sorry your jacket is not
being uh is not moved first of all and
second is when you do restrict the
Motions it should not be there should
not be a defect or there should not be
any deflections or any any damage to the
jacket during your restrictions so for
that we are using we do a c fasting
analysis to make sure sure the forces
are okay so there are different types of
fastening you can use welded connections
so usually we'll be doing welded
connections most of the time when you
have pipes or big pipes that you're
going to transport for pipelines Etc you
will be using stanchions and lashing so
lashing will be used when you have uh
pipes and or you have small structures
which you don't need to have huge welded
connections or something like that then
you will be using lashing for pipes
usually you'll use tangents and welded
connections are used for top sides and
jackets huge structures okay so this is
your uh see fastening
so transportation is going to be
including off to find out your sea
fastening forces or to get your uh
motion forces whatever as a motion
forces you need to do this so to get
your analysis so here we have to play
around with hydrodynamics uh depending
on the shape of your structure depends
sorry shape of your vessel uh depending
on the wave conditions depending on wind
wave current how your structure is going
to respond to the different motions is
where you will run the analysis here and
find out throwing off the structure from
your application here to destination
after proper C first so this is how your
transportation is going to happen this
is a launch barge and this is going to
be launched into the jacket so this is
the transportation of a eight leg Jacket
using a launch barge Towing is going to
be the process of moving a non okay this
is nothing to do with it this is just a
how do you know I use usually you have
Towing once you do install or once you
put the jacket into water you will do
Towing but that is not a very uh serious
analysis or anything you just need to
know the toe capacity of the bullet pull
of the uh towing machine that's a small
very small uh analysis run or
calculation to get the analysis uh
Towing ball article of the towing
launching so launching is the final step
of Transportation of a barge it is not
necessarily the the final step because
there are different jackets depending on
different jackets and different
methodologies you have either launching
or lifting you can do the objective is
to put the jacket in the water that is
the objective so you can either lift it
in four point lifting and you can put it
into water or you can directly launch it
into into water in this method if it's a
top side you will lift it you will pick
it up and keep it on top of the jacket
or it's a float over process that you
will have when you do a top site so
these are the methods which you can use
for installing or putting the jacket
into the water and once the jacket is in
water you have something called appendix
go into now this is the process where
you will be operating the jacket where
the jacket is made is gone from
horizontal to Vertical right so you can
do appending by two methods one is going
to be lifting and one is going to be
controlled flooding so lifting means you
can lift it you can use a crane and you
can hold on to the jacket and you can
just lift it and the jacket will come up
right because you'll be lifting it only
from the top side of from the top in
that case it will automatically lift it
will become appended the second case is
by control flooding in which you don't
use a crane but you use flood lines and
you will you will do control flooding of
the jacket the leg will be controlled
will be flooded by controlling the
valves and that is where the flood lines
come into picture and you will start
flooding the bottom legs and as the
water fills up that portion will go down
because of the weight and it will
upright itself and then due to the
weight the jacket will come and see
about the C bed so that is another way
of water
water line times as we for at the for
the step one is that the compartments
are filled at the bottom of the jacket
so that the jacket can be operated and
then once it is upright we have to fill
at the water line tank so that the
weight is increased and the jacket goes
and sits on the seat yeah so this is uh
a friendly Crane and the other one is
not shown here but we will be doing that
in sex to see that we can see it inside
how it is done after that there is pile
driving but this is nothing to do with
our analysis This Is How We Do the pile
driving the jacket leg is going the pile
is going through the leg and the pile
driver is used to uh drive it through
this is a top side installation you will
just lift the jacket and go install this
is the right directly kept on top of the
jacket legs yeah so that's pretty much
it for uh an overview of the idea so
hope you you got some some idea on the
terminology and how it works and all
that yeah I prefer that you you
concentrate more on the jacket portion
because the top side is going to be like
any other structure but jacket portion
will be a little bit more of a uh
terminologies and terms coming up the
operations all this will be different
for
a jacket
so that's the next point I wanted to
know because uh I'm not sure what you
have been told or what where so what is
the expectation of what we are going to
be covering here uh we are basically
going to go through the sex my objective
is going to be to make you understand
sex software we are not going to go into
in-depth of analysis questions or
structural design we are not doing
offshore structural uh design portion we
are more concentrating on this on
software itself so uh anything related
to snack software I can cover and I can
sort it out for you uh because anything
more than that would be more into design
portion which is the actual design of
jackets and actual design of uh top
sides and all that so that portion
actually we're not going to be covering
uh so I'm not sure what they have told
you about it so I just wanted to clarify
is that and uh we will be taking I I
expect to take about uh every five days
of two hour classes that is what
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