Premium connections and oil drilling technology has come a long way from the traditional vertical wells of the late 19th and early 20th century. There are several different types of oil wells in use today that provide increased oil production and can access oil in places traditional wells were never able to reach. Here is an explanation of three modern oil drilling methods.
Directional oil wells are wells that feature bores that can dig at an angle away from the well. These wells have revolutionized the oil drilling industry because of their many advantages over vertical wells. Directional wells can reach oil reservoirs that are buried under areas where a vertical drill cannot be installed, such as cities or parks. These wells can be erected miles away from the target reservoir, eliminating the negative effects that a well would have on the community if it was closer to a city.
Directional wells can search for and tap oil reservoirs within a 360-degree radius that is miles across. This greatly reduces the density of wells that is required to draw the same amount of oil from a particular location. This smaller surface footprint reduces the impact that the oil wells has on the environment without reducing productivity. Additionally, directional wells have a much higher pay zone than vertical wells because their bores can run along the length of a horizontal reservoir in the rock, instead of boring below them as a vertical well would do.
Injection wells are a class of oil wells that use additive techniques to stimulate oil production. Water or gas is pumped through the bores of the well to increase pressure within the reservoir. The increased pressure will then force the oil back up through the bores. There are several different gases and fluids that injection wells can use to stimulate oil production, such as carbon dioxide, superheated steam, or hazardous and non-hazardous waste materials.
The most common type of injection wells is the water injection well. These wells use several different water sources for their operation, including seawater that is pumped in from offshore, river water, or brine that is produced as a natural byproduct of the drilling process. Water that is used in water injection drilling is first passed through sand filters to remove impurities, and is then deoxygenated in a deoxygenation tower to prevent corrosion inside the well. The water then passes through high-pressure pumps that send it down the bores of the well. Because water and oil are immiscible, the oil is naturally pushed up through the bores while the water replaces it in the reservoir.
Building offshore wells comes with many challenges that are not present in onshore wells, and for this reason they are much more expensive. The drill pipe of an offshore well must be able to pass through the water column before reaching the seafloor, so it must be strong enough to handle the intense pressure and tidal forces of the deep ocean.
Most offshore platforms are located just off the continental shelf in relatively shallow water, although it is also possible to construct mobile offshore drilling units that can drill in the middle of the ocean. These wells are anchored to the continental shelf with a drilling platform that rests on the surface of the ocean. To connect the underwater drilling site to the platform, a steel box is cemented into a hole on the ocean floor and the bores of the well are run through the box. These rigs are permanent and stable, and are typically only built above large, productive reservoirs due to their high cost to build.
Modern oil drilling methods have greatly improved the productivity, safety, and affordability of oil drilling, and these methods will continue to improve to support the multi-billion dollar global oil industry.