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ILLED WEIG F TE

ING TR H

CONC RE

12 JUNE, 2010 - PROPOSED WELL CAPPING TOOL by: @FairDealDaveNH twitter

STEEL SUPPORT BRACES TO TIE PLUG TO CONCRETE WEIGHT RING

CUT AWAY TOP VIEW TAPERED STEEL PLUG WITH HOLLOWED OUT CENTER

NEW BOP & MAIN VALVE ASSEMBLY

SIDE VIEW CONCRETE WEIGHT RING

OCEAN FLOOR

C A S I N G

D R I L L P I P E

C A S I N G

OCEAN FLOOR


12 June, 2010 - PROPOSED WELL CAPPING TOOL - @FairDealDaveNH

It should be first noted that the proposed well capping tool requires removal of the existing valve structure. I realize this would only be a last ditch effort if the current valving and capping means were to fail or a more permanent capping means was required if the relief wells fail. However, competent engineers will realized that there are aspects of the proposed hydraulic side seals that could be applied to the current mitigation structure if the riser that has been left in place above the BOP is of sufficient length. My proposal is as follows: This would only be used if just about everything else failed as it would require removing all of the valving on the well at present. It allows for the possibility that the drill pipe will not fall away once cut off. It is not anticipated that this would cap the well just catch all of the oil and gas until relief wells do their job or not. Therefore, the concrete weight ring does not have to be of a sufficient weight to hold back the full pressure of the reservoir. The brown areas are the flow paths for the oil and gas to get to the surface for collection or burning. The purple center plug is made of machinable steel bar stock. The surfaces in contact with the flow could be hardened or coated to prevent erosion. The center is drilled out to accept the drill pipe if it is present after cuttng. Down near the tapered end a through hole is drilled to allow for oil and gas in the annular ring to get into the center through hole up around the drill pipe and travel up through the new valve structure to the surface for collection or burning. The green on the sides are hydraulically activated urethane side seals. What I have not shown is that these are actually inset into machined areas of the center plug and the hydraulic fluid enters through channels machined into the plug as well. Also not shown but obvious are the hydraulic control lines to the surface to actuate the side seals and valves. To provide of a better “bite” into the wall of the casing thin barbed hardened steel bands could be added around the outside of the urethane seals. These thin bands would be “barb pierced” from both sides to create 100‘s of upward pointing barbs. These barbs would “bite” into both the urethane and the casing and the upward pressure of the well would actually lock them in tighter. The top seal is maintained by the


12 June, 2010 - PROPOSED WELL CAPPING TOOL - @FairDealDaveNH

weight of the concrete ring although some other type of clamp could be devised for the securing to the outside of the well casing. The capping tool would be lowered down to a point just above the current structure. When ready the current valving would be removed by cutting or unbolting. This would necessarily allow for full uncontrolled flow of gas and oil so time is critical. Once the way is clear the new capping tool would be lowered into place. The ROV’s would guide the tapered end into the riser and the final guidance is then provided by the taper itself. Before the process is started the LMRP valves would be opened to the sea so that there would be no appreciable back pressure in the well bore as the gas and oil will be directed initially to the sea water pressure only. This also means that the cement weight ring only needs to be of sufficient weight to overcome the delta P of the initial gas and oil plus whatever back pressure delta P is caused by closing the sea outlet valve when the tool is set into its production configuration. Once the capping tool is fully inserted the hydraulic pressure is applied to the side seals. Once sides are sealed into the riser the sea valve can slowly be closed directing the gas and oil to the surface through the new BOP valve and riser. The BOP valve may not be necessary or usable since full well pressure would most likely break the side seals or the casing anyway. An added feature of this device is that it could be easily tested in either shallow or deep water. A new “test well” could be drilled in the sea floor with a riser configuration matching the current one but only down say 50 feet. The test well would have the ability to have oil (or the like) & gas (compressed air or the like) pumped into the test well from the bottom to simulate the current conditions. The capping tool could then be inserted just as if this were the leaking well and the procedure could be repeated as often as necessary until all variables had been accounted for. This would increase the probability of first time success on the leaking well. I’m sure Oil, Naval and NASA engineers could finalize the design of the device. They could then perform all computer modeling and build and test the device. I feel it would be worth building a device like this in parallel with the current mitigation means as a possible backup in case the current valving structure is compromised for some reason or the relief wells are not immediately successful.


12 June, 2010 - PROPOSED WELL CAPPING TOOL - @FairDealDaveNH

Thank you for your time, consideration and most importantly your critiques. @FairDealDaveNH twitter

Proposed Well Capping Tool  

Possible capping/collection tool for the leaking oil well in the Gulf of Mexico

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