LINER AUGMENTATION OF HORIZONTAL DRILLING

The field test of our liner augmentation of horizontal drilling* was successful. We did it in Mustang, OK with Davis Environmental Drilling. This is what we did:

1. Drilled a horizontal pilot hole with an exit.
2. Replaced the bit with a reamer, swivel and pig.
3. Followed the reamer/pig back through the hole with an everting water driven liner.
   

4. After exiting the hole, ran the liner out on the ground another hole length.
5. Inserted the end of the casing into the inverted liner, inverted the liner, pulling the casing and liner into the hole.
   

6. Pulled the liner off of the casing (via a trick), while peeling the liner from the hole.
   

Advantages:

1. The hole wall is continuously supported.
2. The drilling fluid is forced, with the cuttings, to flow out of the pilot hole.
3. The reamed hole has minimum drilling fluid invasion and no cuttings in the hole.
4. The casing and screen are not entrapped by hole caving.
5. The casing and screen see minimum tensile loads, since the liner carries the load. The friction is only of the liner on itself, and the casing can be of nearly neutral buoyancy for most materials.
6. An instrumented liner can be installed between the hole liner and the hole wall, after step 4 of the procedure, a la the "duet" method. This allows measurements of pore fluids before the casing is installed.
7. Trimmie pipes can be attached to the outside of the casing string for emplacement of a filter pack as needed.

  

  

  

  

  

  

Applications

• In unconsolidated sands and gravels where the mud can not control caving.
• In wells requiring the minimum mud invasion of the medium
• When it is desirable to use inexpensive or fragile screens or a fragile covering is desired on the screen
• When it is desirable to sample the medium pore fluids before installing the screen
• When it is desirable to have a clean hole free of mud and cuttings
• If it is desirable to use a smaller drill rig without the pulling capacity for a long casing
• When a smaller borehole is desirable for a given casing size

Recent Application for horizontal water sampling

We designed and installed a liner which was fully instrumented to pump pore water samples from 8 ports (5 ft. sampling intervals) in a long horizontal hole beneath a landfill. See LAHD FLUTe system for details on that installation. Our duet technique allows many different kinds of liners to be emplaced side-by-side in horizontal holes.

* FLUTe now has four patents on this horizontal technique.

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