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
  • E21B4/00—Drives for drilling, used in the borehole
• • 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
  • E21B4/00—Drives for drilling, used in the borehole
  • E21B4/02—Fluid rotary type drives
• • 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
  • E21B4/00—Drives for drilling, used in the borehole
  • E21B4/20—Drives for drilling, used in the borehole combined with surface drive
• • 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
  • E21B44/005—Below-ground automatic control systems
• • 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
  • E21B7/28—Enlarging drilled holes, e.g. by counterboring

Definitions

• the object of the invention is an oil, gas or geothermal drilling rig, comprising a central tool and a coaxial drill bit, in which the central tool is driven by the rotor of a downhole motor powered by drilling mud. and in which the drill bit is driven from the surface by the rods of a drilling train belonging to a rotary system, these same rods subjecting the apparatus to an axial force.
• a device meeting this definition in such an apparatus, the combined action of the two tools aims to use the energy contained in the mud to increase the overall energy of the drilling, which becomes necessary to keep a sufficient speed of advance when the diameter of the well becomes large .
• Another possible advantage of this organization is to allow the central tool to rotate at a higher angular speed than the drill bit, and thus to achieve more uniform linear cutting speeds over the major part of the diameter of the drilled well.
• the drilling rig securely fastens the base of the drill bit and the stator of the downhole motor.
• the power distribution is optimal in the only case where the drilled ground and the cutting conditions imposed on the two tools are such that the feed speeds which would be taken by each of them would be identical if they acted separately . Any deviation from this ideal situation manifests itself in a poor instantaneous distribution of power and a problematic realization of the expected benefits.
• the drilling device which is the subject of the invention comprises a prismatic connection so as to allow the relative translation of the two tools along their common axis.
• any means comprising an elasticity, which we will call spring, is interposed between the stator of the downhole motor and the base of the drill bit so that the stator forces this spring when the central tool tends to fall behind the drill bit in their respective advance movements.
• the stator of the downhole motor and the base of the drill bit have shapes delimiting between them an orifice whose section is a function of their relative positions, allowing the deviation of a variable part of the flow of mud, which thus avoids the intake port of the bottom engine.
• the drilling rig modifies the deflection orifice so as to increase the flow admitted into the motor when the relative axial displacement of the stator is in the direction in which it tends to constrain the spring and vice versa.
• a freewheel can be interposed between the base of the central tool and the drill bit.
• This freewheel is obviously of a type which makes it powerless to oppose the relative axial displacement of the two tools and it is mounted so as to lock when the absolute rotation speed of the central tool tends to become lower than that of the drill bit.
• FIG. 1 to 3 of the accompanying drawing describe by way of example an embodiment of the drilling rig, object of the invention, in which are present all the provisions listed above.
• Figure 1 shows an axial section of
• Figure 2 shows, on an enlarged scale, a partial section II-II of Figure 1 (the engine being viewed from above without being cut).
• FIG. 3 is a part, on an enlarged scale, of the axial neck presented in FIG. 1.
• the device Between the stator 4 of the downhole motor and the base 5 of the drill bit, the device comprises a prismatic connection 450.
• the base is here in two parts assembled by the conical thread 51.
• the prismatic connection 450 is here produced by a groove comprising four teeth 40 on the stator, engaged between teeth 50 belonging to the base 5 of the drill bit.
• the spring 5 working in compression bears, in 570, on the base of the drill bit and, in 416, on four projections 41 of the stator 4, the head surfaces of these projections forming, in 451, a complementary cylindrical guide of the stator in the base of the drill bit.
• the projections 41 of the stator 4 have, on the other hand, bearing faces 452 which may constitute, with bearing faces 532 on the projections 53 of the base 5 of the drill bit, a stop enabling the device to be extracted from the well without lose part of it.
• the flow of mud which has passed through the orifice 7 circulates in the annular space 453 between the base 5 of the drill bit and the stator 4 of the downhole motor, crosses the orifices 52 which constitute restrictors, then crosses the drill bit and reaches the well by holes 20 formed in the body of the drill bit.
• the drilling rig also comprises a free roller wheel (211) interposed between the surface 21 of the bore of the base of the drill bit 2 and a bearing surface of the base 11 of 1 Outi 1 cent al 1.
• This freewheel is mounted so that it locks when the absolute rotation speed of the central tool tends to fall below that of the drill bit.

Landscapes

• Engineering & Computer Science (AREA)
• Life Sciences & Earth Sciences (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)
• Mechanical Engineering (AREA)
• Earth Drilling (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=9412030

Family Applications (1)

Country Status (8)

Families Citing this family (26)

Family Cites Families (12)

• 1991
  • 1991-04-12 FR FR9104824A patent/FR2675197B1/fr not_active Expired - Fee Related
• 1992
  • 1992-04-03 RU RU9293058191A patent/RU2062861C1/ru active
  • 1992-04-03 WO PCT/EP1992/000771 patent/WO1992018740A1/fr active IP Right Grant
  • 1992-04-03 CA CA002104010A patent/CA2104010C/fr not_active Expired - Fee Related
  • 1992-04-03 DE DE69206792T patent/DE69206792T2/de not_active Expired - Fee Related
  • 1992-04-03 EP EP92907586A patent/EP0578690B1/de not_active Expired - Lifetime
• 1993
  • 1993-10-11 NO NO933660A patent/NO305406B1/no not_active IP Right Cessation
  • 1993-12-10 US US08/129,170 patent/US5343964A/en not_active Expired - Fee Related

Non-Patent Citations (1)

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