Methods and apparatus for cementing drill strings in place for one pass drilling and completion of oil and gas wells

• US 7,108,084 B2
• Filed: 12/24/2003
• Issued: 09/19/2006
• Est. Priority Date: 10/14/1994
• Status: Expired due to Fees

• Current Assignee: Weatherford/Lamb Incorporated (Weatherford International PLC)
• Original Assignee: Weatherford/Lamb Incorporated (Weatherford International PLC)
• Inventors: Vail, William Banning III
• Primary Examiner(s): Tsay, Frank
• Application Number:
  US10/746,711
• Publication Number:
  US 20040140128A1
• Time in Patent Office: 1,000 Days
• Field of Search: 175/318, 175/317, 175/402, 175/107, 166/54, 166/386, 166/192, 166/1
• US Class Current: 175/57
• CPC Class Codes: E21B 10/64 characterised by the whole or part thereof being insertable into or removable from the borehole without withdrawing the drilling pipe
• CPC Class Codes: E21B 21/10 Valve arrangements in drilling-fluid circulation systems
• CPC Class Codes: E21B 23/00 Apparatus for displacing, setting, locking, releasing or removing tools, packers or the like in boreholes or wells setting of casings, screens or liners E21B43/10
• CPC Class Codes: E21B 23/001 Self-propelling systems or apparatus, e.g. for moving tools within the horizontal portion of a borehole
• CPC Class Codes: E21B 33/14 for cementing casings into boreholes
• CPC Class Codes: E21B 33/16 using plugs for isolating cement charge; Plugs therefor stage cementing E21B33/146; spacer compositions C09K8/424
• CPC Class Codes: E21B 7/065 using oriented fluid jets
• CPC Class Codes: E21B 7/20 Driving or forcing casings or pipes into boreholes, e.g. sinking; Simultaneously drilling and casing boreholes

Abstract

The steel drill string attached to a drilling bit during typical rotary drilling operations used to drill oil and gas wells is used for a second purpose as the casing that is cemented in place during typical oil and gas well completions. Methods of operation are described that provide for the efficient installation of a cemented steel cased well wherein the drill string and the drill bit are cemented into place during one single drilling pass down into the earth. Apparatus is described having a portion of a drilling assembly that is selectively removable from the wellbore without removing the casing. A one-way cement valve is installed near the drill bit of the drill string that allows the cement to set up efficiently under ambient hydrostatic conditions while the drill string and drill bit are cemented into place during one single drilling pass into the earth.

Claims

1. An apparatus for drilling a wellbore, comprising:

a drill string having a casing portion for lining the wellbore;

a drilling assembly operatively connected to the drill string and having an earth removal member, a portion of the drilling assembly being selectively removable from the wellbore without removing the casing portion; and

a latching float collar valve which, following removal of the portion of the drilling assembly from the wellbore, is pumped from the surface of the earth through the drill string with drilling mud so as to seat the latching float collar valve above the earth removal member.

2. A method of making a cased wellbore, comprising:

assembling a lower segment of a drill string comprising in sequence from top to bottom a first hollow segment of drill casing, a drilling assembly having a selectively removable portion and a rotary drill bit, the rotary drill bit having at least one mud passage for passing drilling mud from the interior of the drill string to the outside of the drill string;

rotary drilling the well into the earth to a predetermined depth with the drill string by attaching successive lengths of drill casing to the lower segment of the drill string and by circulating mud from the interior of the drill string to the outside of the drill string during rotary drilling so as to produce a wellbore;

retrieving the selectively removable portion of the drilling assembly from the wellbore;

pumping a latching float collar valve down the interior of the drill string with drilling mud until it seats into place within the drilling assembly;

pumping a bottom wiper plug down the interior of the drill string with cement until the bottom wiper plug seats on the upper portion of the latching float collar valve so as to clean the mud from the interior of the drill string;

pumping cement into the wellbore by forcing the cement through a portion of the bottom wiper plug and through at least one mud passage of the drill bit into the wellbore;

pumping a top wiper plug down the interior of the drill string with water until the top wiper plug seats on an upper portion of the bottom wiper plug thereby cleaning the interior of the drill string and forcing additional cement into the wellbore through at least one mud passage of the drill bit; and

allowing the cement to cure, thereby cementing into place the drill string and the drilling assembly and the drill bit to make a cased well.

3. The method of claim 2, further comprising measuring geophysical parameters.

4. The method of claim 2, further comprising curing the cement under ambient hydrostatic conditions.

5. The method of claim 4, further comprising releasing pressure on the interior of the drill string after the top wiper plug seats on the bottom wiper plug.

6. The method of claim 2, further comprising providing one or more stabilizers to the drill string.

7. The method of claim 2, wherein drilling the well comprises directional drilling.

8. The method of claim 7, further comprising surveying the wellbore to determine angle and direction.

9. Rotary drilling apparatus to drill a borehole into the earth, comprising:

a hollow drill string possessing a drilling assembly having a selectively removable portion and a rotary drill bit, the rotary drill bit having at least one mud passage for passing the drilling mud from within the hollow drill string to the borehole,

a source of drilling mud,

a source of cement, and

at least one latching float collar valve whereby, after the total depth of the borehole is reached, and after retrieving the removable portion from the wellbore the latching float collar valve is pumped with the drilling mud into place above the rotary drill bit to install the latching float collar within the hollow drill string above the rotary drill bit that is used to cement the drill string and rotary drill bit into the earth during one pass into the formation of the drill string to make a steel cased well.

10. A method of drilling a well from the surface of the earth and cementing a drill string into place within a wellbore to make a cased well during one pass into formation using an apparatus comprising at least a hollow drill string possessing a drilling assembly having a selectively removable potion and a rotary drill bit, the drill bit having at least one mud passage to convey drilling mud from the interior of the drill string to the wellbore, a source of drilling mud, a source of cement, and at least one latching float collar valve assembly, comprising at least the following steps:

after the total depth of the wellbore is reached, retrieving the retrievable portion from the wellbore;

thereafter pumping the latching float collar valve from the surface of the earth through the hollow drill string with drilling mud so as to seat the latching float collar valve above the drill bit; and

thereafter pumping cement through the seated latching float collar valve to cement the drill string and rotary drill bit into place within the wellbore.