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Another Makeshift Bridge Plug self-anchors to the Drill Stem

The premise of this is to have a lower resistance as the device is pushed down the well on the drill stem, then with a rotating motion, increase the surface area of the blockage.  The pressure on each blockage plate will create a torque on each section of pipe over the drill stem, which will anchor the assembly to the drill stem.  Steel wedges can be driven between the pipe sections and the drill stem to reinforce anchoring.

The “lower resistance” is a function of having 7 blockage plates in the “shadow” of the first.  Approximately one eighth of the final blocking surface area faces down the well.

There are simple mechanisms that will lock these in alignment with each other for the insertion, and then allow full rotation so all eight block the flow.

Dual fins behind each plate are required. The drawing shows one for simplicity’s sake.

The load experienced is spread across all eight pieces and in eight sections of the drill stem.

If you don’t think this will anchor to the drill stem, go to a gym, and put  a flat-surfaced 25 pound Olympic weight on an Olympic bar, and try to pull it off using one hand on one edge.  The torque and the square angle (90 degree) and the diameter prevent it.

Click on the image to enlarge it.

Push assemblies into place with a pipe over drill stem, rotate to fully deploy and reduce crude flow rate

The challenge will be getting this on the drill stem with 60,000 barrels a day of oil coming out of the top of the well.   This can be overcome by diverting the oil away from the center of the remaining riser pipe with temporary inverse-cone-shaped steel sections.

A clean cut with the diamond band saw is now possible since the weight of the bent riser pipe is no longer a factor.  Evidently the people directing the cut never took a chainsaw to a large tree… of course it was going to bind the way they cut it!

I have a feeling this is all just wasted yelling in the wind of a hurricane, but I had to get this out.  That we all seem to be forced to wait for the holy-crap-hail-mary-long-odds directionally drilled relief well is driving me insane.

These are a couple of quick drawings of the drill-stem attached flow reducing mechanism I discussed on Grist.org.  Successively larger versions would be sent down well to reduce the flow for an eventual top kill.

The force experienced by these drill stem attachments will manageable by the components as they are not subjected to the full force of the flow since each attachment is only meant to restrict the flow partially.

The force is equal to the pressure times the surface area of the attachment.  These can be estimated to ensure the cam axis shafts and assembly won’t shear or disintegrate.

The cams can plate steel cut by a laser (very easily… I know a shop) and built up by lamination, bolting and /or welding together as many layers as required to attain required thickness.

The following is the front view.. or the view from the bottom of the well looking up the drill stem shaft. Since I’m currently handicapped by only having Visio to draw, it’s all square. It could be a cylindrical assembly. It would be August before I finished drawing it…. Regardless, the first of a few of these pushed deep into the well will be the smallest, followed by successively larger ones to block more and more of the diameter of the casing, reducing flow enough for a successful top kill.

This is extremely simple. It can be made quickly, and unless the drill stem has protrusions I don’t know about, can be implemented quickly.

1. Cut a slot in the riser pipe with circular saw
2. Slowly insert steel plate to gradually block most of the bore, slowing crude flow rate, gradually building backpressure.
3. With flow rate throttled down, do a successful top kill

Minor modification of a grapple like one below could attach an apparatus that could insert a steel plate into the riser pipe. The grapple is needed to anchor the operation.

Adapt a grapple like one of these Dymax units to include plate insertion device

Thanks to Dymax Inc for posting the pic.

Additional grapples can and should be fixed to riser pipe and chained to weights on ocean floor to provide anchoring support for when pressure builds in the riser pipe so the riser and BOP don’t get pulled off the well casing pipes.

With a steady and slow decrease of diameter, the pressure will build…

With a decrease in flow rate, all the drilling mud will not get “washed” out.

Since I wrote yesterday, it’s become obvious they have the necessary sawblade at the bottom of the Gulf. Now it is stuck… This may be a good thing for now.

The leak can be greatly reduced by the simplest action…
1. cut slot in riser pipe.
2. insert steel plate, greatly reducing diameter of pipe open to the ocean.
3. The velocity of escaping crude will be greatly diminished.
4. NOW do the Top Kill. With the flow reduced, the injected mud and junk has a chance to form a solid blockage.

I’ll update with a diagram on how to reinforce a steel plate flow restrictor.