What is a drilling platform? Types of drilling platforms

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

Mining is carried out with the help of special engineering structures - drilling platforms. They provide the necessary conditions for development to take place. The drilling platform can be equipped at different depths - it depends on how deep the oil and gas fields lie.

Drilling on land

Oil occurs not only on land, but also in the continental plume, which is surrounded by water. That is why some installations are equipped with special elements, thanks to which they stay on the water. Such a drilling platform is a monolithic structure that acts as a support for the rest of the elements. Installation of the structure is carried out in several stages:

• first, a test well is drilled, which is necessary to determine the location of the field; if there is a prospect of developing a specific zone, then further work is carried out;
• preparing a platform for a drilling rig: for this, the surrounding area is leveled as much as possible;
• the foundation is being poured, especially if the tower is heavy;
• on a prepared basis, a drilling tower and its other elements are assembled.

Methodsdeposit identification

Drilling platforms are the main structures on the basis of which oil and gas development is carried out both on land and on water. Construction of drilling platforms is carried out only after the presence of oil and gas in a particular region is determined. To do this, a well is drilled using various methods: rotary, rotary, turbine, volumetric, screw and many others.

The most common is the rotary method: when it is used, a rotating bit is driven into the rock. The popularity of this technology is due to the ability of drilling to withstand significant loads for a long time.

Platform loads

The drilling platform can be very different in design, but it must be built competently, primarily taking into account safety indicators. If they are not taken care of, the consequences can be severe. For example, due to incorrect calculations, the installation may simply collapse, which will lead not only to financial losses, but also to the death of people. All loads that act on installations are:

• Constant: they mean the forces acting throughout the operation of the platform. This is the weight of the structures themselves above the installation, and the resistance of water, if we are talking about offshore platforms.
• Temporary: such loads act on the structure under certain conditions. Only during the start of the installation is there a strong vibration.

Different types of drilling platforms have been developed in our country. To date, on8 stationary production systems operate in the Russian pipeline.

Surface platforms

Oil can occur not only on land, but also under water. To extract it in such conditions, drilling platforms are used, which are placed on floating structures. In this case, pontoons, self-propelled barges are used as floating facilities - this depends on the specific features of oil development. Offshore drilling platforms have certain design features, so they can float on the water. Depending on the depth of the oil or gas field, different drilling rigs are used.

About 30% of oil is extracted from offshore fields, so wells are increasingly being built on water. Most often this is done in shallow water by fixing piles and installing platforms, towers, and the necessary equipment on them. Floating platforms are used to drill wells in deep water areas. In some cases, dry drilling of water wells is performed, which is advisable for shallow openings up to 80 m.

Floating platform

Floating platforms are installed at a depth of 2-150 m and can be used in different conditions. Such structures can be compact in size and work in small rivers, or they can be installed in the open sea. A floating drilling platform is an advantageous structure, since even with a small size, it can pump out a large volume of oil or gas. And this makes it possible to save on transport costs. Such a platform isat sea for a few days, then returns to base to empty the tanks.

Fixed platform

Stationary offshore drilling platform is a structure that consists of a topside and a supporting base. It is fixed in the ground. The design features of such systems are different, so the following types of stationary installations are distinguished:

• gravitational: the stability of these structures is ensured by the own weight of the structure and the weight of the received ballast;
• piling: they gain stability due to piles driven into the ground;
• mast: the stability of these structures is provided by guys or the required amount of buoyancy.

Depending on the depth at which oil and gas are being developed, all stationary platforms are divided into several types:

• deepwater on columns: the base of such installations is in contact with the bottom of the water area, and columns are used as supports;
• shallow-water platforms on columns: they have the same structure as deep-water systems;
• construction island: such a platform stands on a metal base;
• monopod is a shallow water platform on one support, made in the form of a tower and has vertical or inclined walls.

It is fixed platforms that account for the main production capacities, as they are more economically profitable and easier to install and operate. In a simplified version, such installations havesteel frame base, which acts as a supporting structure. But it is necessary to use stationary platforms taking into account the static nature and depth of water in the drilling area.

Installations in which the base is made of reinforced concrete are laid on the bottom. They do not need additional fasteners. Such systems are used in shallow water fields.

Drilling barge

Exploratory drilling offshore is carried out by means of mobile rigs of the following types: jack-ups, semi-submersibles, drilling ships and barges. Barges are used in shallow water fields, and there are several types of barges that can operate at very different depths: from 4 m to 5000 m.

The barge-shaped drilling platform is used in the initial stages of field development when it is necessary to drill wells in shallow water or protected areas. Such installations are used in the mouths of rivers, lakes, swamps, canals at a depth of 2-5 m. Most of these barges are not self-propelled, so they cannot be used to work on the high seas.

The drilling barge has three main components: an underwater submersible pontoon that is installed on the bottom, a surface platform with a working deck, and a structure that connects these two parts.

Climbing platform

Jack-up drilling platforms are similar to drilling barges, but the former are more modernized and improved. They rise on jack-masts that rest on the bottom.

Structurally, such installations consist of 3-5 supports with shoes, whichare lowered and pressed into the bottom for the duration of drilling operations. Such structures can be anchored, but supports are a safer mode of operation, since the hull of the installation does not touch the surface of the water. The self-elevating floating platform can operate at depths up to 150 m.

This type of installation rises above the surface of the sea thanks to columns that rest on the ground. The upper deck of the pontoon is the place where the necessary technological equipment is mounted. All self-elevating systems differ in the shape of the pontoon, the number of support columns, the shape of their section and design features. In most cases, the pontoon has a triangular, rectangular shape. The number of columns is 3-4, but in early projects the systems were created on 8 columns. The derrick itself is either located on the upper deck or extends aft.

Drilling ship

These rigs are self-propelled and do not need to be towed to the job site. Such systems are designed specifically for installation at shallow depths, so they are not stable. Drilling ships are used in oil and gas exploration at a depth of 200-3000 m and deeper. A drilling rig is placed on such a vessel, and drilling is carried out directly through the technological hole in the deck itself.

At the same time, the vessel is equipped with all the necessary equipment so that it can be operated in all weather conditions. The anchor system allows you to ensure the proper level of stability on the water. The produced oil after purification is stored in special tanks in the hull, and then reloaded into cargo tankers.

Semi-submersible

Semi-submersible oil drilling platform is one of the popular offshore drilling rigs as it can operate at depths of over 1500m. Floating structures can submerge to considerable depths. The installation is complemented by vertical and inclined braces and columns, which ensure the stability of the entire structure.

The upper body of such systems is the living quarters, which are equipped with the latest technology and have the necessary supplies. The popularity of semi-submersible installations is explained by a variety of architectural solutions. They depend on the number of pontoons.

Semi-submersible installations have 3 types of draft: drilling, storm water mode and transition. The buoyancy of the system is provided by supports, which also allow the installation to maintain a vertical position. It should be noted that work on drilling platforms in Russia is highly paid, but for this you need to have not only the appropriate education, but also extensive work experience.

Conclusions

Thus, the drilling platform is a modernized system of various types, which can drill wells at different depths. The structures are widely used in the oil and gas industry. Each installation is assigned a specific task, so they differ in design features, functionality, processing volume, and transportation.resources.