DIRECTIONAL DRILLING SERVICES
This section describes the reasons for requiring directional drilling, commonly known as HDD (Horizontal Directional Drilling). It includes the types of drilling routes used and the tools and techniques used in drilling these wells.
Most directional drillers are given a blue-outlined path of a wellbore to follow, which is determined in advance of the drill operation by engineers and geologists.
Using advanced software programs, engineers can generate 3D models of an oil reservoir to identify an optimal well site and optimal entry points to conduct the directional drill.
DIRECTIONAL DRILLING USE CASES
Directional drilling is widely used for placing pipelines under ground and rivers and has even been used by telecom companies for installing fibre-optic cables.
This way of installing conduit has several benefits, including fewer interruptions of business operations, fewer disruptions to transportation, and fewer rehabilitations to the property.
Directional drilling can also be used to avoid damaging wetlands, streams, and river crossings.
An experienced directional drilling team can guide and direct directional drilling bits up, down, right, left, and combinations of each of these degrees to bore a desired horizontal boring path.
Modern directional drilling techniques have improved directional drilling, using drill bits that can flex to better fit off-vertical angles.
HOW DIRECTIONAL DRILLING WORKS
We now have directional drill machines that can move a drill bit to an entirely different orientation than a conventional 180deg starting downhole.
Once a sensor verifies the bit is pointed the correct way, the drill string starts turning again.
The drills rotational velocity, as well as the drill string's weight and stiffness, can also be used to affect the direction.
Before drilling begins, crews plan their bore route in advance, taking care to avoid obstacles, such as other subterranean utilities.
Each pipe obstruction and situation is unique; therefore, prior to an HDD contractor being allowed to release its boring machinery; an evaluation must be made of the areas to the sides of the obstructions in order to determine the feasibility of the bore's exit and entrance points.
Pipe layout areas and drawback areas behind the access points of the bore will also be identified, in order to provide space to operate the HDD contractor.
Drilling vertically through the saline dome increases the likelihood of well problems, such as clogging, loss of circulation, and erosion.
It is generally challenging to drill vertical wells through a steeply inclined fracture plane in order to access an underlying hydrocarbon-bearing formation.
Until modern downhole engines and drilling tools that can measure hole inclination and azimuth, directional drilling and horizontal drilling were far slower than vertical drilling because of the need to periodically stop and perform labor-intensive surveys, as well as slower drilling progress (lower rate of penetration).
Counter-experience also gave the first Directional Drillers (dD) principles for BHA designs and drilling practices which helped to move the tilted hole closer to vertical.
This might have meant requiring an entirely new set of equipment, while the new well may need to be drilled again slightly off-center.