OIL WELL SAFETY VALVE APPARATUS AND METHOD |
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| 申请号 | US14467823 | 申请日 | 2014-08-25 | 公开(公告)号 | US20150041147A1 | 公开(公告)日 | 2015-02-12 |
| 申请人 | Raymond C. Davis; | 发明人 | Raymond C. Davis; | ||||
| 摘要 | An oil well control device automatically shuts in a well responsive to the removal of a work string (or other removable structure—ball retarding structure) from the device. The device is placed in the well as a section of the well casing. The device provides a pair of bores, one that aligns with the well bore or well casing, the other being a branch flow line containing a ball structure that will close the well if the drill pipe or drill string is removed. While conducting normal well activity (e.g. drilling, work over or the like) the ball retarder (e.g. work string) prevents entry of the ball structure into the main flow channel. | ||||||
| 权利要求 | |||||||
| 说明书全文 | This is a non provisional patent application of U.S. Provisional Patent Application Ser. No. 61/356,905, filed Jun. 21, 2010, and U.S. Provisional Patent Application Ser. No. 61/361,204, filed Jul. 2, 2010. Priority of U.S. Provisional Patent Application Ser. No. 61/356,905, filed Jun. 21, 2010, and U.S. Provisional Patent Application Ser. No. 61/361,204, filed Jul. 2, 2010, each of which is incorporated herein by reference, is hereby claimed. Not applicable Not applicable 1. Field of the Invention The present invention relates to an oil well safety device that automatically shuts in or closes an oil well if the drill string is removed or responsive to removal of the drill string to a position above the safety device. 2. General Background of the Invention In the exploration of oil, wells are drilled many thousands of feet into the earth. Tremendous pressures can exist in formations where oil is located. Drillers use heavy fluids such as drilling mud to control well pressures and prevent a catastrophic blow out wherein oil and gas escape from the well bore. There are various control devices that hopefully close the well bore before a blow out can occur. Examples include blow out preventers, sub surface valves, sub surface safety valves and the like. Most such safety control devices require activation by personnel on a drilling structure. If these valve blow out preventers or valve structures cannot be actuated, blow out still occurs. The present invention provides an improved oil control device that automatically shuts in a well responsive to the removal of a drill string from the device. The device is thus placed in the well as a section of the well casing. The device provides a pair of bores, one that aligns with the well bore or well casing, the other being a branch flow line containing a ball structure that will close the well if the drill pipe or drill string is removed. While drilling, the drill string prevents entry of the ball structure into the main flow channel. The present invention thus provides an oil safety shut off method. As part of the method, there is provided a section of well casing having a well bore and the casing including a device having a first flow bore of a first diameter aligned generally with the well bore of the casing. In this fashion, flow through the casing also flows through the first flow bore with a first diameter. A second flow bore is provided that communicates with the first bore at two spaced apart positions to provide a lower flow entry from the first flow bore and an upper flow discharge into the first flow bore, the second flow bore having a diameter that is larger than the first diameter. There is an upper ball seat above the upper flow discharge. A lower ball seat is provided in the second flow bore in between the lower flow entry and the upper flow discharge. A ball valving member is contained in the second flow bore above the lower seat. The method disallows entry of the ball valving member into the first flow bore by placing a ball retarding member in the first flow bore. The ball retarding member can occupy a position within the first flow bore next to the upper flow discharge. A removal of the ball retarding member enables the ball valving member to form a seal with the upper ball seat, slowing the flow of fluids upwardly in the first flow bore. In one embodiment, the ball retarding member can be a work string. In one embodiment, the ball retarding member can be a drill string. In one embodiment, the ball retarding member can be a tube or tubing. In one embodiment, the ball retarding member can be a member that extends to a work deck, drill deck, platform, work vessel, or earth surface area. For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein: Oil well safety shut off apparatus is shown in A drill string, work string or other string 13 extends downwardly into the well bore 12 and through the first bore 23 of the device 10. Circulating mud 21 can be located in first bore 23. First bore 23 has a diameter dl designated by the numeral 19. Diameter 19 of first bore 23 and the diameter of the well bore (i.e. casing 11 internal diameter) can be equal (see A branch flow line 14 has a bore 15 with a diameter (d2) designated by the numeral 20 and larger than the diameter designated by the numeral 19. The branch flow line 14 communicates with the first bore 23 at two spaced apart positions, namely lower opening 24 and upper opening 25. A ball structure 17 is carried in branch flow line bore 15 in between openings 24, 25 as shown. There is a lower seat 16 that prevents downward movement of ball valving member 17. There is an upper seat 22 or seal ring that prevents upward movement of valving member 17 should work string (or other ball retarding member) be removed from bores 12, 23 to a position above opening 25 and seat 22. First bore 23 can have a guide 27. Guide 27 can be used to help track the ball structure 17 during its travel. During normal well activity, ball retarding structure or work string 13 prevents entry of ball 17 into bore 12 or 23 (see The following is a list of suitable parts and materials for the various elements of a preferred embodiment of the present invention. The foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims. |
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