4. Mobile Drilling Platform
Mobile drilling platform is being used in the exploratory drilling, to drill
and to find out if there’s oil and then move on to the next site.
Mostly, the oil company didn’t have the mobile drilling platforms. Since
it is more cost effective to hire expertise and equipment needed than to
keep it under their roof.
The expertise in here refers to the drilling contractor and the service
company like Transocean, Schlumberger, Pride, Frontier, and Sea-Drill.
There are 5 varieties of mobile drilling platforms: drilling barge, jack
up, semi-submersible rig, submersible rig, and drill ships.
5. Drilling Barge
Mostly used in the swamps or coastlines, the drilling
barge has a specification of work about less than 7
meter of water depth.
6. Jack up drilling rig
Jack up oil rigs are limited to shallow water drilling
(typically < 300 feet). A jack up typically has 3 or 4
long legs (up to 350 feet high), each leg is jacked
down to the sea floor until they support the weight of
the entire unit lifting it out of the water. When all
safety checks are complete, and the unit is found
secured, the unit will switch to drilling mode and
begin drilling the well.
(featured video)
7. Submersible Drilling Rig
This drilling platform combines some of the
properties of drilling barges and jack ups. Only in this
case, the production facilities are elevated on stilts
hundreds of feet above pontoon like barges. After
reaching the drill site. The crew floods the barges
with water. The barges sink until they rest on the sea
or lake floor, while the platform remains elevated
above the water on stilts. Like jack-up, this platform
is limited to shallow waters.
8. Semi-Submersibles drilling rig
This unit is called as semi-submersible because once
this unit is over the proposed well drilling
location, they flood their huge ballast tank with the
sea water and partially submerge below surface of the
water.
Semi-submersible will work for 300-2000 ft ocean
depth.
Semi-submersible has the advantage of being very
stable in rough environments, but limited by the
amount of equipment and supplies they are able to
store on board.
9. more with Semi-Submersibles
There are 2 ways on how semi-submersible able maintain its position
over a proposed well, using the anchors and the dynamic positioning
system (DP system).
10. Anchor method
Anchor method is considered as a traditional method of keeping a semi-
submersible on location. Up to 12 anchors are run out away from the unit
and set on ocean floor. The tension in the anchor chain or cable is
increased by using a large winch.
11. Dynamic Positioning System
With a DP system, the semi-submersible uses position information from
GPS system and radio beacons on the ocean floor to constantly monitor
its position. If the DP computer detects that the oil rig is drifting off
location (either caused by the wind, waves, or current), huge thrusters
underneath the rig will apply thrust to push it back over the well.
12. Drill ship
Over the last 15 years, drills hips have been built to
meet the growing demand for highly capable ultra-
deepwater drilling rigs.
Today’s generation of deepwater drill ships use the
DP system for maintaining its position.
Drill ship is capable of working for extended periods
without the need for constant resupplying (larger
storage capacity than semi-submersible).
Other benefit of drill ship is their speed and
maneuverability, drill ship can secure their operation
and sail out of harms way like hurricane.
16. About Offshore Engineers
Offshore oil and gas engineers play a critical role in all facets of offshore operations.
Their skills are used in designing and constructing platform and subsea
structures, drilling equipment, well head operations, subsea pipelines, production and
transportation operations.
Offshore engineers can branch out into many specialties including: drilling and
completions, robotics, marine corrosion, consulting and project
management, pipelines, process control and systems, intervention and tooling, quality
control and inspection, flow assurance, and subsea processes.
Chemical engineering degrees are typically required in process engineers or corrosion
engineers.
17. The working conditions
Offshore oil and gas engineers work in both onshore and offshore locations. While
onshore, they perform their work in an office setting. Trips by helicopter to offshore
platforms and or vessels can occur frequently, so be prepared by it. Accommodation
and meals are provided, workers maybe exposed to inclement weather and potentially
hazardous conditions; however safety protocols are strictly adhered to in order to avoid
any risk. Periods of stay out at sea will vary depending on the project assignment.
18. Some criteria needed in becoming an
offshore engineer
It takes a very unique person set to be able to survive and thrive in the offshore
world, this are some criteria mentioned in careersinoilandgas.com
• Good at math, sciences, and technology
• Consider yourself at a great team-player, able to easily build personal and
professional relationships.
• Have the stamina and enthusiasm to work on ships, platforms, and other unique
offshore work environments.
• Can handle traveling for long periods.
• Comfortable working 24/7 in a relatively isolated environment, with harsh weather
conditions.
• Think a career as an offshore engineer is exciting.
19. SKC : OFFSHORE OPERATION
part 2
ARIF FAJAR UTOMO
L2C008118
Semarang, April 20th 2012