Oil is produced and extracted in a few countries, but consumed worldwide, right? The extraction of oil is not a straightforward process. It requires dedicated machines and structures to reach beneath the earth’s surface. For this purpose, specialized oil rigs are used. Interestingly, there are different types of oil rigs available to be used.
These oil rigs differ in many ways. Some of these oil rigs are suitable for use on land. In contrast, some offshore oil rigs drill and extract oil from the water surface. All the types of oil rigs operate differently, which makes them stand out. In this article, I will discuss all the major types of oil rigs. So, let’s get started.
What are Oil Rigs?
Before discussing oil rig types, I will help you understand what oil rigs are!
An oil rig is a dedicated structure that houses machinery and other components. The components of these oil rig drills reach beneath the earth’s surface, where oil is present. For drilling, these machines use drill bits that cut material as they go down. Once oil is found, it is extracted using dedicated steel pipes.
As you know, oil is present beneath the Earth’s surface. Therefore, drilling is an essential process for accessing this oil and extracting it. Oil rigs’ structures help drill into the earth, allowing us to extract oil from underground. Interestingly, the oil rigs can be used on both onshore and offshore surfaces. These rigs consist of different parts and components, which are as follows:
- Casing
- Drill Bit
- Mud Tanks
- Mud Pumps
- Shale Shaker
- Derrick (or Mast)
- Substructure or base
The derrick is the most important component of oil rigs. It is a tower that supports the whole drilling or oil extraction process. The drill bits on these oil rigs drill deep into the ground. These drill bits remove the different layers of earth that reach deeper, where oil reserves are present. During drilling, a specialized mud system is used to cool and clean the drill bits.
This mud also removes the cut rocks and other hard materials from the path. Once an oil reserve is found, the steel pipes are put into the drilled location. The purpose of these steel pipes (casing) is to provide stability to the drilled well. As a result, the well does not collapse. However, inside these steel pipes or casings, other tubes are placed. The purpose of these tubes is to flow the oil out of the well, which is then processed and refined.
Types of Oil Rigs
As I said above, there are two primary types of oil rigs. Their names are as follows:
- Onshore oil rigs
- Offshore oil rigs
Both of these oil rigs serve the same function: oil extraction. However, onshore oil rigs are located on land. They drill into the land, drilling down through different layers to reach the oil reservoir. The basic structure of these oil rigs remains on the land. These rigs are simple, easy to use, and cheaper.
On the other hand, offshore oil rigs are used to extract oil present underneath the seabed. This means these rigs are used in seas or oceans (deeper waters). The structure of these rigs remains submerged. They drill into the seabed and extract the oil. This extracted oil is then transferred to the storage compartment or vessels through tubi marini.
Their use is more challenging, and they are much more expensive than onshore oil rigs. Both of these oil rigs (onshore and offshore) have further subtypes. In the section below, I will explain the different types of oil rigs (both onshore & offshore).
1- Mobile Drilling Rigs
As the name suggests, these drilling rigs are movable. This means these rigs can be transported from one location to another. As a result, these oil rigs are ideal options for large companies handling multiple projects. They will be able to use these drilling rigs to extract oil efficiently from various locations.
These oil rigs are loaded onto large trucks or containers for transportation. It is worth noting that mobile drilling rigs are only used for onshore oil fields. However, these oil rigs are suitable for shallow oil reserves. The reason is that mobile drilling rigs are not powerful enough to extract oil from very deep oil reserves.
2- Fixed Platform Rigs
The fixed platform rigs are installed on the seabed to extract the oil. They have long legs that go deeper into the ocean. These legs provide stability to the whole structure in the ocean. Since these are fixed, they are generally installed in locations with higher oil reserves. These rigs operate at a single location and extract oil in bulk. Fixed platforms are more expensive and complex than mobile drilling rigs. Additionally, these offshore oil rigs are large and accommodate workers.
3- Hydraulic Drilling Rigs
In the past, oil rigs relied more on mechanical systems for their operations. However, these hydraulic drilling rigs are unique. How? They use a hydraulic system for their work. Hydraulic oil or fluid creates the pressure that powers the different components of these rigs. This pressure, created by the hydraulic fluid, makes the operation of these rigs more efficient. Many companies prefer these hydraulic-based drilling rigs primarily because of their cost-effectiveness. Interestingly, they work efficiently and are used only on onshore oil fields or wells.
4- Jackknife Rigs
Jackknife rigs are known for their portability and compact size. These oil rigs can be easily moved from one oil field to another. Interestingly, they have a foldable derrick (a tower platform). This means when this oil rig is operating at an oil field, the derrick or mast is extended. However, when relocating the rig, this derrick is folded for easier transportation. These oil rigs are generally used on onshore fields where oil reserves are not too deep. Oil companies consider jackknife rigs a solution for short-term oil extraction or drilling.
5- Jack-Up Rigs
Jack-up rigs are types of offshore oil rigs that can float on the water. Therefore, companies generally bring offshore oil fields into production by floating them. They have long legs, which help with their positioning and installation in the oil field. These legs sit down on the seabed while the other structures remain above the water. These legs provide support as jack-up rigs begin drilling and oil extraction. Generally, offshore oil rigs cannot be relocated, right? However, Jack-Up rigs can be moved from one offshore oil field to another using their floating features.
6- Semi-Submersible Rigs
Semi-submersible rigs are neither fully submerged nor floating on the surface. Instead, they are in between and are positioned using long anchors. These rigs have their lower parts submerged in the water body. This way, their lower part remains safe against harsh waves and tides. However, the upper parts, which contain many components, remain outside the water. It is not submerged, which gives these rigs the name “semi-submersible.” These rigs are useful when companies extract oil from deepwater. Drilling in deep water becomes easier with these semi-submersible oil rigs.
7- Floating Rigs
Floating oil rigs are among the most expensive types used in various offshore oil fields. These rigs keep floating during their operations. It is worth noting that these rigs are anchored in place. As a result, these rigs remain in a specific area and drill at the right location. These rigs can even drill and extract oil from very deep-water reserves.
Operating these floating rigs requires specialized skills. Why? The reason is that these rig structures are stationary through anchors and computerized systems. Operators must be skilled at handling these controls to keep the oil rig stationary. As the name indicates, these rigs can be relocated from one offshore oil field to another with ease.
8- Barge Rigs
Some oil reserves are in shallow water. The example can include lakes, swamps, rivers, and other bodies of water. In such cases, barge rigs are handy, as they can easily drill and extract oil from calm water. These rigs are called barges because their entire structure is built on a large flat platform.
As a result, these oil rigs are called barge rigs. Barge oil rigs are very sensitive to tides and waves. If exposed to waves, these oil rigs may not function properly. It is commonly used in calm or very shallow water, such as lakes or rivers. Moving the barge rigs is effortless from one oil field to another. Additionally, these oil rigs are less costly, which is a significant advantage.
Conclusione
Let’s end this – oil rigs are important for modern oil extraction companies. These machines drill and then securely extract raw oil. This raw oil is then processed and refined to produce various types of oils used in our daily lives. However, different types of oil rigs are used at different locations to extract oil.
Each of these oil rigs has its own unique pros and cons and specialties. Some rigs are ideal for onshore oil wells, while others are best suited for offshore oil reserves. In this article, I have explained eight common oil rigs. Some of these are used on land (onshore) while others are preferred for offshore oil extraction. You should understand each type of oil rig before choosing one for your custom project.