Classifications

• • E—FIXED CONSTRUCTIONS
  • E21—EARTH OR ROCK DRILLING; MINING
  • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
  • E21B7/00—Special methods or apparatus for drilling
  • E21B7/04—Directional drilling
• • E—FIXED CONSTRUCTIONS
  • E21—EARTH OR ROCK DRILLING; MINING
  • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
  • E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
  • E21B43/02—Subsoil filtering
  • E21B43/10—Setting of casings, screens, liners or the like in wells
• • E—FIXED CONSTRUCTIONS
  • E21—EARTH OR ROCK DRILLING; MINING
  • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
  • E21B44/00—Automatic control systems specially adapted for drilling operations, i.e. self-operating systems which function to carry out or modify a drilling operation without intervention of a human operator, e.g. computer-controlled drilling systems; Systems specially adapted for monitoring a plurality of drilling variables or conditions

Definitions

• the present invention relates to an improved method for the drilling of oil wells which allows the positioning of lining columns, operating with an almost constant clearance for the whole of the desired well depth and which substantially consists in effecting the drilling, guaranteeing the elimi- nation of any geometrical curvature and irregularities of the hole, whether it be vertical or deviated.
• lining operations of the hole are effected which comprise the positioning of appropriate casings at pre-established intervals in relation to the depth reached and characteristics of the formations penetrated.
• the clearance between casing and hole can vary from values of about 6-7 inches (15-16 cm) for the surface and/or intermediate phases, to values of almost an inch for the deeper phases (for example: 26" hole for 20" conductor pipe, 17 1/2" hole for 13 3/8", 12 1/4" hole for 9 5/8" casing, 8 1/2" hole for 7" casing) .
• the drilling method according to the present invention allows, with the same diameter of the production column, the dimensions of the upper well part (surface and intermediate columns) to be re- symbolized. This enables a significant reduction in the consumption of materials (mud, cement and steel) and consequently the production of waste products.
• This technique also avoids the necessity of producing holes with a diameter which is too large with respect to the diameter of the columns to be lowered, which generally implies the possibility of effecting holes with a smaller diameter compared to the conventional technique. All of this positively influences the advancement rate of the bit there- fore allowing the production times of the holes to be reduced, with a consequent decrease in the costs.
• the technique according to the present invention also enables a significant reduction in the operating costs, as the verticality and/or regular curvature of the well facilitates all workover and well intervention operations.
• This method comprises a drilling and pipe- laying technique which allows the positioning of the lining columns operating with an almost con- stant clearance with values of more or less 1.5 inches (3-4 cm) for the whole well depth (from the top to the bottom) , or in any case for the whole of the desired well depth.
• a reduced clearance allows, with the same number of columns and final diameter of the production casing, the dimensions of the upper part of the well to be greatly reduced.
• An object of the present invention therefore relates to an improved method for the drilling of oil wells and for the contemporaneous positioning of appropriate casings, characterized in that the clearance is kept almost constant for the whole of the desired well depth, consisting in drilling the well section of interest, maintaining a high degree of hole regularity by the use of automatic verti- cality and/or curvature control equipment.
• the method according to the following invention comprises effecting the drilling phase according to the following procedures: automatic control of the verticality and/or curvature of the well; use of bits equipped with adequate distribu- tors and roller reamers, in order to guarantee hole regularity and calibration; use of drilling mud with chemical and rheological characteristics which are such as to minimize any possible problems of hole in- stability; constant control of all the drilling parameters in order to maintain a curvature (BUR/DO) of 0.7 degrees every 30 , with a maximum slope of 1.5 degrees in the vertical sections.
• SDD Straight Hole Drilling Device
• This device contrary to the conventional systems, automatically effects a continuous correction of the verticality and is based on a retro-activated control which ensures the absolute verticality of holes, even in formations which have a strong ten- dency to cause the bit trajectory to deviate from the vertical.
• the pipe-laying procedure is effected as follows. After producing a perfectly vertical and well calibrated hole the lining columns can be lowered into the well. In order to facilitate the passage of the casing into the hole calibrated with a re-zad clearance, the following precautions should be observed:
• curvature should be planned in relation to the flexibility of the casings to be used.
• Figure 1 compares the conventional pipe-laying program with the "Lean” program.
• the data in said figure were obtained in the Monte Enoc 9 well ef- fected in the Field of Val D'Agri in Basilicata. It is evident how with the "Lean” solution, starting from a lower diameter of the surface and intermediate columns, a production column is obtained with the same diameter as that produced with the conven- tional solution.
• Figure 2 describes a further two examples of Lean pipe-laying, which can provide a valid alternative to the previous scheme, above all in contingency situations.
• Figure 3 schematically represents a comparison between the hole sections.

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• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Geology (AREA)
• Mining & Mineral Resources (AREA)
• Physics & Mathematics (AREA)
• Environmental & Geological Engineering (AREA)
• Fluid Mechanics (AREA)
• General Life Sciences & Earth Sciences (AREA)
• Geochemistry & Mineralogy (AREA)
• Earth Drilling (AREA)
• Steroid Compounds (AREA)

Priority Applications (7)

Applications Claiming Priority (2)

Publications (1)

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ID=11443623

Family Applications (1)

Country Status (13)

Cited By (2)

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Citations (4)

Family Cites Families (2)

• 2000
  • 2000-01-05 IT IT2000MI000007A patent/IT1316157B1/it active
  • 2000-12-28 BR BR0016888-2A patent/BR0016888A/pt not_active Application Discontinuation
  • 2000-12-28 AU AU33676/01A patent/AU3367601A/en not_active Abandoned
  • 2000-12-28 WO PCT/EP2000/013370 patent/WO2001053655A1/en not_active Application Discontinuation
  • 2000-12-28 CA CA002396282A patent/CA2396282A1/en not_active Abandoned
  • 2000-12-28 CN CN00818206.XA patent/CN1420958A/zh active Pending
  • 2000-12-28 OA OA1200200205A patent/OA12135A/en unknown
  • 2000-12-28 EP EP00991655A patent/EP1244866A1/en not_active Withdrawn
  • 2000-12-28 EA EA200200605A patent/EA200200605A1/ru unknown
  • 2000-12-28 US US10/168,526 patent/US20020189864A1/en not_active Abandoned
  • 2000-12-28 MX MXPA02006734A patent/MXPA02006734A/es unknown
• 2002
  • 2002-06-28 NO NO20023169A patent/NO20023169L/no not_active Application Discontinuation
  • 2002-07-01 MA MA26717A patent/MA25880A1/fr unknown

Patent Citations (4)

Non-Patent Citations (4)

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