Polyurethane components play a prominent role in horizontal drilling operations, both at the surface and in promoting the material stability of downhole operations.
You don’t hear as much about horizontal drilling as you do about hydraulic fracturing (also called “fracing” in the industry and “fracking” outside the industry). Let’s take a look at why this directional boring technique is playing such a huge role in the comeback of the modern oil and gas industry.
Horizontal directional drilling (HDD) was initially used in the 1930s to relieve wells under high pressure. The technique is still used for this purpose. Even with sophisticated blowout prevention technology, a crew may need to intersect a vertical well when high pressures threaten to compromise the well and force a shutdown. A horizontal “relief well” can lower pressure to safe levels or seal the well off permanently.
As we head into 2018, horizontal drilling has an even more critical application: increasing the productivity of gas wells, particularly in shale plays.
Reservoirs are like underground lakes. They may be miles and miles across, yet only a few feet deep. A vertical well, therefore, has a shallow “pay zone” (the part of the well that is extracting oil or gas). Since horizontal wells can traverse the full length of an oil and gas reservoir, the pay zone is much larger.
HDD also gives us access to underground and subsea reservoirs that would otherwise be impossible to reach. Traditional, vertical wells don’t work so great when the reservoirs are beneath populated areas or protected lands. Horizontal wells can tap those resources with minimal disruption to the land surface above them.
As stated, drilling horizontally can dramatically improve productivity because it can give crews a larger pay zone. A horizontal well can also do the work of several vertical wells. Since dozens of vertical wells may be required to map and drain a reservoir, operations can take up a lot of space. Crews must build access roads, drilling pads and ponds for each well. Horizontal wells can be grouped closer together, reducing the drilling footprint — as well as the labor and cost required to operate.
When operations are in hard-rock formations, HDD has yet another advantage over vertical drilling. Traditional wells are great in highly permeable rock, where less pressure is needed to push the oil or gas into the well.
In denser, low-permeability fields, however, a vertical well may be unable to exert the pressure necessary to drag in hydrocarbons. A horizontal well, on the other hand, can punch a hole through these impermeable formations and take us closer to the oil and gas.
Fracing and Horizontal Drilling
Horizontal directional drilling is often combined with hydraulic fracturing to make fantastic producers of formations that were unproductive when drilled vertically. A horizontal well is effective at delivering high-pressure fluid to pores of dense rock saturated with hydrocarbons. The Marcellus Shale of the Appalachian Basin and the Bakken Formation of North Dakota are terrific oil or natural gas producers that combine fracing and HDD.
We’ve listed quite a few benefits to horizontal wells. But what about the downsides? The first one that springs to mind is surveying costs. Since surveyors need to constantly ensure the well is on target, there’s a lot more surveying involved. HDD also requires additional technology to execute efficiently. Still, these other costs can be significantly outweighed by the increased productivity of the wells.
The Role of Polyurethane
Modern drilling processes continue to improve, and polyurethane parts play a role in this development. Oil and gas companies need durability and reliability from their tools. They need equipment that resists corrosion, pressure, abrasion, impact and heat. They need products that can be machined to meet strict specifications.
Polyurethane elastomers deliver all these characteristics and more. Mark Tool & Rubber can equip your operation for success. We also offer splash zone protection, anti-corrosive products, molded rubber tools, urethane rollers and more.