Boring or penetrating the earth – Boring with explosion in inaccessible hole
Reexamination Certificate
1999-02-23
2001-07-10
Neuder, William (Department: 3672)
Boring or penetrating the earth
Boring with explosion in inaccessible hole
C175S061000, C175S062000
Reexamination Certificate
active
06257353
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates to horizontal drilling into strata surrounding a well casing.
2. Description of the Related Art
Typically, oil and gas wells are vertically oriented structures going into the earth's strata to access oil and gas formations buried deep in the earth. In many cases, this vertical structure adequately taps into the petroleum formations. However, in most cases the petroleum is not stored in simple pools or caves that can be easily tapped. The petroleum is often in multiple pockets scattered at many levels and locations in an oil field. Often, various pockets of petroleum are positioned near existing wells but, because of the formation, the petroleum will not flow to the opening provided by the existing well. Digging a new vertical well to access these deposits is too expensive.
Various techniques have been developed to try to tap into nearby deposits to existing wells. Most of these techniques involve mechanical tools that must operate at some angle deep within a well. The goal is to provide a puncturing of the well casing and extension of the bore hole to a formation laterally positioned from an existing well. One technique for accomplishing this is provided by Bull et al., U.S. Pat. No. 3,958,649. Mechanisms such as that shown in Bull et al. use complex mechanical devices in harsh environments operating deep beneath the ground. Therefore, effective tools using these techniques are expensive to manufacture and difficult to use in the field.
There are a number of known methods for horizontally drilling into a formation surrounding an existing well. U.S. Pat. No. 4,640,362 to Schellstede teaches a method of penetrating a well casing and surrounding earth strata with the use of a punch member for cutting through the well casing. The punch member includes a retractable jet nozzle means for penetrating the surrounding earth's strata after the punch member has cut through the casing. An alternative technique is described in U.S. Pat. No. 5,413,184 to Landers. The latter patent describes a multi-step method that begins with the insertion of a flexible shaft having a ball cutter on an end thereof into upset tubing within a well casing. The upset tubing is provided with an elbow at its lower extremity for receiving the ball cutter therein. The ball cutter cuts a hole in the well casing and is then moved horizontally a given distance. The flexible shaft and ball cutter are then removed and a flexible tube having a nozzle blaster on the end thereof is then inserted into the upset tubing. A fluid of surfactant and water at high pressure is then pumped into the tube to cut an extension into the previously cut channel.
BRIEF SUMMARY OF THE INVENTION
It is an object of the present invention to provide an economical technique for horizontal drilling through existing well casings.
It is a further object of the present invention to provide a technique that allows for the positioning of lateral drilling at any point in the existing well.
These and other objects of the invention are provided in a novel horizontal drilling method. According to the invention, after removal of production equipment from the wellbore, a shoe having an elbow-shaped cavity therein is lowered to a selected point where it is desired to drill a lateral (i.e., a horizontal) extension) in the strata. An explosive charge is then placed at a given radial position and set off. The charge is preferably bullet-shaped to focus the explosive force in a direction that minimizes material backflow into the shoe, and the charge is preferably activated using a impact mechanism. Alternatively, the charge is set off electronically. The charge preferably has an ogive configuration to cause it to veer once it penetrates the well casing. An impact head or projectile, composed of a material that shatters, such as Tungsten Carbide, on the tip of the charge ensures penetration of the casing while avoiding the possibility of impeding subsequent lateral drilling steps.
After the casing is perforated, a nozzle is dropped down into the shoe via coiled tubing and a flexible tube used to drill the lateral. Preferably, the nozzle is rotated and outputs a high pressure fluid, e.g., water or a mixture of a surfactant and water. In an alternative embodiment, the well casing is perforated using a steel punch that is activated with the impact hammer via a slickline.
Thus, in accordance with a preferred embodiment of the present invention, a shaped explosive charge is placed within an upset tubing adjacent to a well casing to be perforated. Impact transferring means are positioned between the explosive charge and the vertical portion of the well above the shoe. An impact is made on the surface of the transfer means to cause an impact-type detonator to discharge, causing the explosive charge to detonate. The charge perforates the casing of the well. The shoe and the tubing above it are then cleared and a hydraulic drilling device is inserted into the shoe. The shoe guides the hydraulic drilling device into place and high pressure liquid is pumped through the hydraulic device that extends through the perforation in the well casing into the earth's strata.
Although use of a shaped explosive charge is preferred, in an alternative embodiment, the well casing is perforated using a steel punch that is activated via slickline with the impact hammer.
REFERENCES:
patent: Re. 33660 (1991-08-01), Jelsma
patent: 1367042 (1921-02-01), Granville
patent: 1485615 (1924-03-01), Jones
patent: 1733311 (1929-10-01), McNeill
patent: 2065436 (1936-12-01), Ervin
patent: 2251916 (1941-08-01), Cross
patent: 2271005 (1942-01-01), Grebe
patent: 2345816 (1944-04-01), Hays
patent: 2381929 (1945-08-01), Schlumberger
patent: 3191697 (1965-06-01), Haines
patent: 3262508 (1966-07-01), Price
patent: 3633686 (1972-01-01), Bennett
patent: 3838736 (1974-10-01), Driver
patent: 3840079 (1974-10-01), Williamson
patent: 3853185 (1974-12-01), Dahl et al.
patent: 3873156 (1975-03-01), Jacoby
patent: 3958649 (1976-05-01), Bull et al.
patent: 4168752 (1979-09-01), Sabol
patent: 4365676 (1982-12-01), Boyadjieff et al.
patent: 4368786 (1983-01-01), Cousins
patent: 4445574 (1984-05-01), Vann
patent: 4526242 (1985-07-01), Mathieii et al.
patent: 4527639 (1985-07-01), Dickinson, III et al.
patent: 4533182 (1985-08-01), Richards
patent: 4589499 (1986-05-01), Behrens
patent: 4601353 (1986-07-01), Schuh et al.
patent: 4640362 (1987-02-01), Schellstede
patent: 4763734 (1988-08-01), Dickinson et al.
patent: 4832143 (1989-05-01), Kaalstad et al.
patent: 4832552 (1989-05-01), Skelly
patent: 4836611 (1989-06-01), El-Saie
patent: 4848486 (1989-07-01), Bodine
patent: 4854400 (1989-08-01), Simpson
patent: 4890681 (1990-01-01), Skelly
patent: 5090496 (1992-02-01), Walker
patent: 5113953 (1992-05-01), Noble
patent: 5148880 (1992-09-01), Lee et al.
patent: 5165491 (1992-11-01), Wilson
patent: 5183111 (1993-02-01), Schellstede
patent: 5279366 (1994-01-01), Scholes
patent: 5392858 (1995-02-01), Peters et al.
patent: 5413184 (1995-05-01), Landers
patent: 5853056 (1998-12-01), Landers
patent: 5934390 (1999-08-01), Uthe
patent: 5944123 (1999-08-01), Johnson
A.W. Iyoho, D.A. Summers, Greg Galecki, U. of Missouri-Rolla, “Petroleum Applications of Emerging High-Pressure Waterjet Technology”1993, Society of Petroleum Engineers #26347.
David A. Summers, Richard L. Henry, “Water Jet Cutting of Sedimentary Rock” Society of Petroleum Engineers Jul. 28, 1971, copyright 1972 American Institute of Mining, Metallurgical and Petroleum Engineers, Inc.
S.E. Forman, G.A. Secor, “The Mechanics of Rock Failure due to Water Jet Impingement”, Jan. 22, 1973, copyright 1974 American Institute of Mining, Metallurgical and Petroleum Engineers, Inc.
Belew Barry
Belew David A.
Hughes & Luce, L.L.P.
Judson David H.
LTI Joint Venture
Neuder William
LandOfFree
Horizontal drilling method and apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Horizontal drilling method and apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Horizontal drilling method and apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2468203