This relates to drilling wells in deep water and particularly to equipment for improving the safety of workers on offshore drilling platforms. As used herein, an offshore platform includes any device for drilling in water.
Drilling in deep water can be a reasonably dangerous activity. When systems fail, workers can be exposed to the risk of fire and explosion.
In the Macondo disaster in the Gulf of Mexico, conventional systems failed. The workers on the platform were then tethered to the well and when the well exploded, many were injured and killed.
Some embodiments are described with respect to the following figures:
In accordance with some embodiments, a tool is provided to implement a severable connection, between riser pipe and a well, for use in emergency situations. Particularly in cases like the Macondo well disaster, where blow-out preventers and shear devices fail, it would be desirable to enable the drilling platform to be separated from the wellhead for the safety of the workers. Otherwise, the workers are effectively tied to the dangerous wellhead, under situations when blow-out preventers and other safety devices have already failed.
In some embodiments, the severing system may be operated completely independently of those hydraulic and electrical systems responsible for operating shear devices and blow-out preventers, which under the circumstances contemplated here, may have failed. Then, because the connection between the riser and the wellhead and the connection between the mux lines and the wellhead may be severed, from a remote location, it is possible to separate the drilling platform from a wellhead. This disconnection allows the drilling platform to move away from the wellhead, possibly reducing injuries and loss of life in some cases.
In
Particularly, kill and choke line mini-connectors 14 connect the lower portion of the kill and choke flexible lines 12 to the upper portion 16. The connectors 14 may be any kind of independently un-lockable connector that is synchronized to disconnect when main connector 18 disconnects. When the main connector 18 is disconnected, the mini-connectors unlock and disconnect at the same time as the main connector, allowing the upper and lower sections to disconnect together.
In some embodiments, the wellhead connector 18 may be an 18-¾″ wellhead connector. The lower part or stub 24 of the device then is left in place connected to the LMRP 10 as shown in
Thus, as shown in
Then, referring to
Thus in
A three cavity blow-out preventer including cavities 34a, 34b, and 34c controls the passage of petroleum product through the center bore of the capping device 30 that communicates with the passage within the stub 24. The passage continues it's upwardly through the running tool 31. A frame 32 surrounds a blow-out preventer 4. Each blow-out preventer cavity includes an internal blind shear RAM 44 remotely controlled by bottle 36 in one embodiment. The hydraulic controls for the shear RAMS are entirely independent of any controls on the wellhead.
Thus, once the capping device 30 is sealed in place, the flow of petroleum product can be shut off by remotely operating the blind RAMs (not shown) within the blow-out preventers 34 to terminate the flow.
Thus, in some embodiments, the sequence is to first independently and remotely unlock the 18-¾″ wellhead connector 18. Then the flexible lines 12 may be unlocked using the quick disconnect 14 including disconnects for kill and choke lines in some embodiments. Next, there may be an attempt to release the emergency disconnect 28 for the mux cables. Finally the device 20, which may be considered a lower marine riser package (LMRP), may be removed as shown in
The overlying offshore platform picks up the capping device 30, that may be contained within an onboard backup conventional lower marine riser package or LMRP connected to a redundant mux cable. Then the capping device is run onto the drill pipe stub 24 and locked on to the open flowing top (using a remote operated vehicle or acoustic techniques), as shown in
Thereafter, the onboard LMRP may be used to drill a relief well. In one embodiment, a new drilling operation may be conducted through the capping device.
Thus in some embodiments it is possible to disconnect the riser above the blow-out preventer. While this may result in the free flow of petroleum products, it may preserve life and reduce injuries to workers on the platform. By using independently operated actuators, it is possible to remove the device 20 even when other protection systems have failed. This removal may be done using remotely operated vehicles, separate cables, an acoustic system or charged nitrogen bottles to activate a relief connection.
References throughout this specification to “one embodiment” or “an embodiment” mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one implementation encompassed within the present invention. Thus, appearances of the phrase “one embodiment” or “in an embodiment” are not necessarily referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be instituted in other suitable forms other than the particular embodiment illustrated and all such forms may be encompassed within the claims of the present application.
While the present invention has been described with respect to a limited number of embodiments, those skilled in the art will appreciate numerous modifications and variations therefrom. It is intended that the appended claims cover all such modifications and variations as fall within the true spirit and scope of this present invention.
Number | Name | Date | Kind |
---|---|---|---|
3688840 | Curington et al. | Sep 1972 | A |
3913668 | Todd et al. | Oct 1975 | A |
4461354 | Buras et al. | Jul 1984 | A |
5676209 | Reynolds | Oct 1997 | A |
7578349 | Sundararajan et al. | Aug 2009 | B2 |
8434558 | Swanson et al. | May 2013 | B2 |
8714263 | Sundararajan et al. | May 2014 | B2 |
8720580 | Lugo | May 2014 | B1 |
20110247827 | Humphreys | Oct 2011 | A1 |
20110284237 | Baugh | Nov 2011 | A1 |
20120048566 | Coppedge et al. | Mar 2012 | A1 |
20120067589 | Fenton | Mar 2012 | A1 |
20120085543 | Redden et al. | Apr 2012 | A1 |
20130020086 | Anderson et al. | Jan 2013 | A1 |
20130032351 | Smith | Feb 2013 | A1 |
20130140035 | Smith et al. | Jun 2013 | A1 |
20130299177 | Lyle | Nov 2013 | A1 |
Number | Date | Country |
---|---|---|
2012099841 | Jul 2012 | WO |
2012140178 | Oct 2012 | WO |
2012142274 | Oct 2012 | WO |
Entry |
---|
International Search Report and Written Opinion dated Jun. 10, 2015 issued in PCT/1B2013003132 (14 pages). |
Wells, K., “BP Macondo MC 252 well capping operations: sealing cap installation presentations,” dated Jul. 7, 2010, Retrieved from the Internet: http://www.bpcom/en/global/corporate.gulf-of-mexico-restoration/deepwater-horizon-accident-and-response/containing-the-leak.html dated Jul. 7, 2010 (55 pages). |
Number | Date | Country | |
---|---|---|---|
20140144646 A1 | May 2014 | US |