Horizontal Drills personnel offers a quick review of horizontal and directional (remember the wells do not have to be horizontal or straight) well installation methodology. There are two types of horizontal well configurations. The first is a double-ended well, installed similar to a utility bore. They design their bore or well path, drill down to depth, across the screen section, then back up to the ground surface on the other end of the well. The screen and casing are pulled back to the rig in tension. Using this method, extremely long wells can be completed. The longest horizontal environmental well is over 2,850 feet long, the longest utility bore is over 12,000 feet. This type of well construction is often referred to as a continuous or entry to exit well.
While continuous wells are the norm, many sites do not have enough room to exit the ground surface due to obstructions or real estate issue (the responsible party does not own the land at the exit point). In that case they install what the industry terms a blind well ... a well that terminates under the ground surface and does not exit.
Blind wells can be somewhat tricky to complete. First they have to drill the borehole, then, while the drilling fluid maintains hole stability, the drill pipe and bit are pulled from the hole. With the borehole held open by the drilling fluid, we then push the well materials into the open borehole. Obviously this type of installation is more difficult than a continuous well for several reasons ...good read.
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Managed & Built by I2M Consulting, LLC | © 2010-
Managed & Built by I2M Consulting, LLC | © 2010-