WebCPC CPC COOPERATIVE PATENT CLASSIFICATION

E21B　EARTH DRILLING, e.g. DEEP DRILLING (mining, quarrying E21C; making shafts, driving galleries or tunnels E21D); OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS

E21B 1/00 Percussion drilling (drives used in the borehole E21B 4/00; rotary drilling machines in general B23B)

E21B 1/02 ・Surface drives for percussion drilling

E21B 1/04 ・・Devices for reversing the movement of the rod or cable at the surface {not used, see E21B 1/02}

E21B 3/00 Rotary drilling (drives used in the borehole E21B 4/00; rotary drilling machines in general B23B)

E21B 3/02 ・Surface drives for rotary drilling

E21B 3/025 ・・with a to-and-fro rotation of the tool

E21B 3/03 ・・with an intermittent unidirectional rotation of the tool

E21B 3/035 ・・with slipping or elastic transmission

E21B 3/04 ・・Rotary tables {(portable drilling rigs with rotary tables E21B 7/021)}

E21B 3/045 ・・・{movably mounted on the drilling structure or platform (derricks adapted to be moved on their substructure E21B 15/003; specially adapted for underwater drilling, E21B 15/02)}

E21B 3/06 ・・・Adaptation of rotary draw works to drive rotary tables (connecting or disconnecting couplings or joints E21B 19/16; rope, cable, or chain winding mechanisms, capstans B66D)

E21B 4/00 Drives used in the borehole

E21B 4/003 ・{Bearing, sealing, lubricating details (for roller bits E21B 10/22; bearings in general F16C; sealing in general F16J; lubricating in general F16N)}

E21B 4/006 ・{Mechanical motion converting means, e.g. reduction gearings (E21B 4/10 takes precedence; gearings in general F16H)}

E21B 4/02 ・Fluid rotary type drives (hydraulic turbines for drilling wells F03B 13/02)

E21B 4/04 ・Electric drives (E21B 4/12 takes precedence)

E21B 4/06 ・Down-hole impacting means, e.g. hammers (percussion drill bits E21B 10/36; boring rams E21B 11/02; releasing-jars E21B 31/107)

E21B 4/08 ・・impact being obtained by gravity only, e.g. with lost-motion connection

E21B 4/10 ・・continuous unidirectional rotary motion of shaft or drilling pipe effecting consecutive impacts

E21B 4/12 ・・Electrically operated hammers

E21B 4/14 ・・Fluid operated hammers

E21B 4/145 ・・・{of the self propelled-type, e.g. with a reverse mode to retract the device from the hole}

E21B 4/16 ・Plural down-hole drives, e.g. for combined percussion and rotary drilling (E21B 4/10 takes precedence); Drives for multi-bit drilling units

E21B 4/18 ・Anchoring or feeding in the borehole

E21B 4/20 ・combined with surface drive (E21B 4/10 takes precedence)

E21B 6/00 Drives for combined percussion and rotary drilling (drives used in the borehole E21B 4/00)

E21B 6/02 ・the rotation being continuous

E21B 6/04 ・・Separate drives for percussion and rotation

E21B 6/06 ・the rotation being intermittent, e.g.obtained by ratchet device

E21B 6/08 ・・Separate drives for percussion and rotation

E21B 7/00 Special methods or apparatus for drilling

E21B 7/001 ・{Drilling a non circular hole (excavating trenches E02F 5/02; cutting machines for slitting E21C 25/00)}

E21B 7/002 ・{Drilling with diversely driven shafts extending into the borehole (simultaneously drilling and casing E21B 7/20; plural down-hole drives E21B 4/16; E21B 7/001 takes precedence)}

E21B 7/003 ・{Drilling with mechanical conveying means (bailers, e.g. baskets, buckets E21B 27/00; tunnelling E21D)}

E21B 7/005 ・・{with helical conveying means (E21B 7/201 takes precedence; augers E21B 10/44; drilling rods or pipes with helical structure E21B 17/22)}

E21B 7/006 ・・・{combined with a bucket-type container (bailers with helical conveying means E21B 27/04)}

E21B 7/007 ・{Drilling by use of explosives (underwater drilling using explosives E21B 7/1245; setting-tools actuated by explosives E21B 23/04, E21B 23/065; cutting or destroying objects in boreholes by explosives E21B 29/02; freeing objects using explosives

E21B 7/008 ・{Drilling ice or a formation covered by ice}

E21B 7/02 ・Portable drilling rigs, truck-or skid-mounted, with their own drive (portable drilling rigs for use on underwater floors E21B 7/124)

E21B 7/021 ・・{With a rotary table, i.e a fixed rotary drive for a relatively advancing tool (rotary tables E21B 3/04)}

E21B 7/022 ・・{Control of the drilling operation; Hydraulic or pneumatic means for activation or operation (control circuits for drilling masts E21B 15/045)}

E21B 7/023 ・・{the mast being foldable or telescopically retractable}

E21B 7/024 ・・{having means for adapting to inclined terrain; having means for stabilizing the vehicle while drilling}

E21B 7/025 ・・{Rock drills, i.e. jumbo drills}

E21B 7/026 ・・{having auxiliary platforms, e.g. for observation purposes}

E21B 7/027 ・・{Drills for drilling shallow holes, e.g. for taking soil samples or for drilling postholes}

E21B 7/028 ・・・{the drilling apparatus being detachable from the vehicle, e.g. hand portable drills}

E21B 7/04 ・Directional drilling (derricks or masts specially adapted therefor E21B 15/04)

E21B 7/043 ・・{for underwater installations}

E21B 7/046 ・・{horizontal drilling (drilling with mechanical conveying means E21B 7/003)}

E21B 7/06 ・・Deflecting the direction of boreholes {(directional window cutting E21B 29/06; deflecting the direction of fishing tools E21B 31/14)}

E21B 7/061 ・・・{the tool shaft advancing relative to a guide, e.g. a curved tube or a whipstock}

E21B 7/062 ・・・{the tool shaft rotating inside a non-rotating guide travelling with the shaft (E21B 7/067 and E21B 7/068 take precedence)}

E21B 7/064 ・・・{specially adapted drill bits therefor}

E21B 7/065 ・・・{using oriented fluid jets}

E21B 7/067 ・・・{with means for locking sections of a pipe or of a guide for a shaft in angular relation, e.g. adjustable bent sub}

E21B 7/068 ・・・{drilled by a down-hole drilling motor (down-hole drives per se E21B 4/00, E21B 7/067 takes precedence)}

E21B 7/10 ・・Correction of deflected boreholes

E21B 7/12 ・Underwater drilling (derricks or masts specially adapted therefor E21B 15/02; telescoping joints E21B 17/07; using heave compensators E21B 19/09)

E21B 7/122 ・・{with submersible vertically movable guide}

E21B 7/124 ・・with underwater tool drive prime mover, e.g. portable drilling rigs for use on underwater floors

E21B 7/1245 ・・・{using explosive means (Anchors driven in by explosive charges B63B 21/28)}

E21B 7/128 ・・from floating support with independent underwater anchored guide base {guide line systems E21B 33/035F}

E21B 7/132 ・・from underwater buoyant support

E21B 7/136 ・・from non-buoyant support (E21B 7/124 takes precedence)

E21B 7/14 ・Drilling by use of heat, e.g. flame drilling {(by use of explosives E21B 7/007)}

E21B 7/143 ・・{underwater}

E21B 7/146 ・・{Thermal lances}

E21B 7/15 ・・of electrically generated heat

E21B 7/16 ・Applying separate balls or pellets by the pressure of the drill, so-called shot-drilling

E21B 7/18 ・Drilling by liquid or gas jets, with or without entrained pellets (E21B 7/14 takes precedence; {obtaining a slurry of minerals E21B 43/29}; hydraulic monitors E21C 45/00)

E21B 7/185 ・・{underwater}

E21B 7/20 ・Driving or forcing casings or pipes into boreholes, e.g. sinking; Simultaneously drilling and casing boreholes (surface means for applying to-and-fro rotation movements to the casing E21B 3/025; {pushing means outside of the borehole E21B 19/08;} placing piles E02D 7/00; sinking shafts while moving the lining downwards E21D 1/08; {making galleries by forcing prefabricated elements through the ground E21D 9/005})

E21B 7/201 ・・{with helical conveying means (drilling with helical conveying means E21B 7/005; augers E21B 10/44; drilling rods or pipes with helical structure E21B 17/22)}

E21B 7/203 ・・・{using down-hole drives (down-hole drives per se E21B 4/00)}

E21B 7/205 ・・{without earth removal (E21B 7/30 takes precedence)}

E21B 7/206 ・・・{using down-hole drives (down-hole drives per se E21B 4/00)}

E21B 7/208 ・・{using down-hole drives (down-hole drives per se E21B 4/00; E21B 7/203 and E21B 7/206 take precedence)}

E21B 7/24 ・Drilling using vibrating or oscillating means, e.g. out-of-balance masses (percussion drilling E21B 1/00)

E21B 7/26 ・Drilling without earth removal, e.g. with self-propelled burrowing devices ({E21B 7/205 and}E21B 7/30 take precedence; down-hole drives E21B 4/00, {e.g. self-propelled fluid-operated hammers E21B 4/145})

E21B 7/265 ・・{Combined with earth removal}

E21B 7/28 ・Enlarging drilled holes, e.g. by counterboring (drill bits for enlarging the borehole E21B 10/26)

E21B 7/30 ・・without earth removal

E21B 10/00 Drill bits (specially adapted for deflecting the direction of boring E21B 7/064; with means for collecting substances E21B 27/00)

E21B 10/003 ・{with cutting edges facing in opposite axial directions}

E21B 10/006 ・{providing a cutting edge which is self-renewable during drilling}

E21B 10/02 ・Core bits (characterised by wear resisting parts E21B 10/46; obtaining undisturbed cores E21B 25/00)

E21B 10/04 ・・with core destroying means

E21B 10/06 ・・Roller core bits

E21B 10/08 ・Roller bits (roller core bits E21B 10/06; with leading portion E21B 10/26; characterised by wear resisting parts E21B 10/46)

E21B 10/083 ・・{with longitudinal axis, e.g. wobbling or nutating roller bit (longitudinal axis roller reamers E21B 10/30)}

E21B 10/086 ・・{with excentric movement}

E21B 10/10 ・・with roller axle supported at both ends (with disc-cutters E21B 10/12)

E21B 10/12 ・・with discs cutters

E21B 10/14 ・・combined with non-rolling cutters other than of leading-portion type

E21B 10/16 ・・characterised by tooth form or arrangement

E21B 10/18 ・・characterised by conduits or nozzles for drilling fluids (drilling fluid supply to the bearings E21B 10/23)

E21B 10/20 ・・characterised by detachable or adjustable parts, e.g. legs or axles (cross axle roller bits E21B 10/10)

E21B 10/22 ・・characterised by bearing, lubrication or sealing details

E21B 10/23 ・・・with drilling fluid supply to the bearings

E21B 10/24 ・・・characterised by lubricating details

E21B 10/246 ・・・・{with pumping means for feeding lubricant}

E21B 10/25 ・・・characterised by sealing details

E21B 10/26 ・Drill bits with leading portion, i.e. drill bits with a pilot cutter; Drill bits for enlarging the borehole, e.g. reamers (percussion drill bits with leading portion E21B 10/40; augers with leading portion E21B 10/44)

E21B 10/28 ・・with non-expansible roller cutters

E21B 10/30 ・・・Longitudinal axis roller reamers, e.g. reamer stabilisers

E21B 10/32 ・・with expansible cutting tools

E21B 10/322 ・・・{cutter shifted by fluid pressure (E21B 10/345 takes precedence)}

E21B 10/325 ・・・{the cutter being shifted by a spring mechanism}

E21B 10/327 ・・・{the cutter being pivoted about a longitudinal axis (E21B 10/34 takes precedence)}

E21B 10/34 ・・・of roller-cutter type

E21B 10/345 ・・・・{cutter shifted by fluid pressure}

E21B 10/36 ・Percussion drill bits (characterised by wear resisting parts E21B 10/46){with helical conveying portion E21B 10/445}

E21B 10/38 ・・characterised by conduits or nozzles for drilling fluids

E21B 10/40 ・・with leading portion

E21B 10/42 ・Rotary drag type drill bits with teeth, blades or like cutting elements, e.g. fork-type bits, fish tail bits (characterised by wear resisting parts E21B 10/54, by conduits or nozzles for drilling fluid E21B 10/60, by detachable or adjustable parts E21B 10/62)

E21B 10/43 ・・characterised by the arrangement of teeth or other cutting elements

E21B 10/44 ・Bits with helical conveying portion, e.g. screw type bits; Augers with leading portion or with detachable parts ({Rotary drag type drill bits E21B 10/42}; drilling rods with helical structure E21B 17/22)

E21B 10/445 ・・{percussion type, e.g. for masonry (percussion drill bits in general E21B 10/36)}

E21B 10/46 ・characterised by wear resisting parts, e.g. diamond inserts {(drill bits with self-renewable cutting edge E21B 10/006)}

E21B 10/48 ・・the bit being of core type {(saw cylinders having their cutting rim equipped with abrasive particles for drilling stone or glass B28D 1/041)}

E21B 10/485 ・・・{with inserts in form of chisels, blades or the like}

E21B 10/50 ・・the bit being of roller type

E21B 10/52 ・・・with chisel or button type inserts

E21B 10/54 ・・the bit being of the rotary drag type, e.g. fork-type bits

E21B 10/55 ・・・with preformed cutting elements {with blades having preformed cutting elements mounted on a distinct support, e.g. polycrystalline inserts}

E21B 10/56 ・・Button type inserts (E21B 10/52 takes precedence)

E21B 10/567 ・・・with preformed cutting elements mounted on a distinct support, e.g. polycrystalline inserts

E21B 10/5673 ・・・・{having a non planar or non circular cutting face (E21B 10/571 takes precedence)}

E21B 10/5676 ・・・・{having a cutting face with different segments, e.g. mosaic-type inserts}

E21B 10/573 ・・・・characterised by support details

E21B 10/5735 ・・・・・{Interface between the substrate and the cutting element}

E21B 10/58 ・・Chisel type inserts ({E21B 10/485,}E21B 10/52, E21B 10/54 take precedence)

E21B 10/60 ・characterised by conduits or nozzles for drilling fluids (for roller bits E21B 10/18; for percussion drill bits E21B 10/38; {mining picks with arrangement of fluid-spraying nozzles E21C 35/187})

E21B 10/602 ・・{the bit being a rotary drag type bit with blades}

E21B 10/605 ・・{the bit being a core-bit}

E21B 10/61 ・・characterised by the nozzle structure

E21B 10/62 ・characterised by parts, e.g. cutting elements, which are detachable or adjustable (E21B 10/64 takes precedence; for roller bits E21B 10/20; {for rotary drag type drill bits E21B 10/42}; for augers E21B 10/44)

E21B 10/627 ・・with plural detachable cutting elements

E21B 10/633 ・・・independently detachable

E21B 10/64 ・characterised by the whole or part thereof being insertable into or removable from the borehole without withdrawing the drilling pipe (retrievable core receivers E21B 25/02)

E21B 10/66 ・・the cutting element movable through the drilling pipe and laterally shiftable

E21B 11/00 Other drilling tools {(boring grabs E21B 27/00)}

E21B 11/005 ・{Hand operated drilling tools}

E21B 11/02 ・Boring rams (percussion drives used in the borehole E21B 4/06; percussion drill bits E21B 10/36)

E21B 11/06 ・with driven cutting chains or similarly driven tools

E21B 12/00 Accessories for drilling tools {(connecting and disconnecting drill bit and drilling pipe E21B 19/18; sharpening stone drill bits B24B 3/33)}

E21B 12/02 ・Wear indicators

E21B 12/04 ・Drill bit protectors

E21B 12/06 ・Mechanical cleaning devices

E21B 15/00 Derricks; Masts; {Other supports (drill rigs with movable understructures E21B 7/02)}

E21B 15/003 ・{adapted to be moved on their substructure, e.g. with skidding means; adapted to drill a plurality of wells (slant-hole rigs E21B 15/04)}

E21B 15/006 ・{Means for anchoring the drilling machine to the ground}

E21B 15/02 ・specially adapted for underwater drilling (E21B 15/04 takes precedence; floating drilling platforms B63B 35/44; drilling platforms on legs E02B 17/00; {with skidding means E21B 15/003})

E21B 15/04 ・specially adapted for directional drilling, e.g. slant hole rigs {(with skidding means E21B 15/003)}

E21B 15/045 ・・{Hydraulic, pneumatic or electric circuits for their positioning}

E21B 17/00 Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; {Cables}; Casings; Tubings (rod couplings in general F16D; tubes or tube couplings in general F16L)

E21B 17/003 ・{with electrically conducting or insulating means (E21B 17/028 and E21B 17/023 take precedence)}

E21B 17/006 ・{Accessories for drilling pipes, e.g. cleaners (wear protectors E21B 17/10; handling drilling pipes E21B 19/00; thread protectors B65D 59/00)}

E21B 17/01 ・Risers ({connections between riser sectionsE21B 17/085; supporting a riser from a drilling or production platformE21B 19/004}; riser connectors{on well heads}E21B 33/038)

E21B 17/012 ・・{with buoyancy elements (E21B 17/015 takes precedence)}

E21B 17/015 ・・{Non-vertical risers, e.g. articulated or catenary-type}

E21B 17/017 ・・{Bend restrictors for limiting stress on risers}

E21B 17/02 ・Couplings; joints {Expandable couplings or joints E21B 43/106}

E21B 17/021 ・・{Devices for subsurface connecting or disconnecting by rotation (connecting or disconnecting pipe couplings or joints E21B 19/16; fishing tools for frozen rods, casings, ropes, bits or the like E21B 31/00)}

E21B 17/023 ・・{Arrangements for connecting cables or wirelines to downhole devices}

E21B 17/025 ・・・{Side entry subs}

E21B 17/026 ・・・{Arrangements for fixing cables or wirelines to the outside of downhole devices (protectors and centralisers for cables and control lines E21B 17/10D)}

E21B 17/028 ・・{Electrical or electro-magnetic connections}

E21B 17/03 ・・between drilling rod or pipe and drill motor, e.g. between drilling rod and hammer

E21B 17/04 ・・between rod {or the like} and bit or between rod and rod {or the like}

E21B 17/042 ・・・threaded {(readily releasing joints E21B 17/06)}

E21B 17/0423 ・・・・{with plural threaded sections, e.g. with two-step threads}

E21B 17/0426 ・・・・{with a threaded cylindrical portion, e.g. for percussion rods}

E21B 17/043 ・・・・with locking means

E21B 17/046 ・・・with ribs, pins or jaws, and complementary grooves or the like, e.g. bayonet catches

E21B 17/05 ・・・Swivel joints

E21B 17/06 ・・・Releasing-joints, e.g. safety joints

E21B 17/07 ・・・Telescoping joints for varying drill string lengths; Shock absorbers (heave compensators in the derrick E21B 19/09; releasing-jars E21B 31/107; {shock-absorbers in general F16F})

E21B 17/073 ・・・・{with axial rotation}

E21B 17/076 ・・・・{between rod or pipe and drill bit}

E21B 17/08 ・・Casing joints

E21B 17/085 ・・・{Riser connections (connectors for wellhead E21B 33/038)}

E21B 17/10 ・Wear protectors; Centralising devices, {e.g. stabilisers}(drives used in the borehole with anchoring means E21B 4/18; guiding or centralising devices outside the borehole E21B 19/24)

E21B 17/1007 ・・{for the internal surface of a pipe, e.g. wear bushings for underwater well-heads}

E21B 17/1014 ・・{Flexible or expansible centering means, e.g. with pistons pressing against the wall of the well (E21B 17/1042 takes precedence)}

E21B 17/1021 ・・・{with articulated arms or arcuate springs (measuring the diameter E21B 47/08)}

E21B 17/1028 ・・・・{with arcuate springs only, e.g. baskets with outwardly bowed strips for cementing operations}

E21B 17/1035 ・・{for plural rods, pipes or lines, e.g. for control lines}

E21B 17/1042 ・・{Elastomer protector or centering means}

E21B 17/105 ・・・{split type}

E21B 17/1057 ・・{Centralising devices with rollers or with a relatively rotating sleeve (E21B 17/1014 takes precedence)}

E21B 17/1064 ・・・{Pipes or rods with a relatively rotating sleeve}

E21B 17/1071 ・・{specially adapted for pump rods, e.g. sucker rods}

E21B 17/1078 ・・{Stabilisers or centralisers for casing, tubing or drill pipes (devices for off-center positioning E21B 17/10; E21B 17/1007 to E21B 17/1064 take precedence)}

E21B 17/1085 ・・{Wear protectors; Blast joints; Hard facing (wear protection included in centralising devices, see relevant subgroups)}

E21B 17/1092 ・・{Gauge section of drill bits}

E21B 17/12 ・・Devices for placing or drawing out wear protectors

E21B 17/14 ・Casing shoes {for the protection of the bottom of the casing}

E21B 17/16 ・Drill collars

E21B 17/18 ・Pipes provided with plural fluid passages ({E21B 17/203 takes precedence;} circulation of drilling fluid by means of such pipes E21B 21/12; {general F16L 39/00})

E21B 17/20 ・Flexible or articulated drilling pipes, {e.g. flexible or articulated rods, pipes or cables (risers E21B 17/01; swivel joints E21B 17/05)}

E21B 17/203 ・・{with plural fluid passages}

E21B 17/206 ・・{with conductors, e.g. electrical, optical (hoses with electrically conducting means in general F16L 11/127)}

E21B 17/22 ・Rods or pipes with helical structure (drill bits with helical conveying portion E21B 10/44)

E21B 19/00 Handling rods, casings, tubes or the like outside the borehole, e.g. in the derrick (surface drives E21B 1/02, E21B 3/02)

E21B 19/002 ・{specially adapted for underwater drilling (E21B 19/09, E21B 19/143 take precedence; risers with buoyancy elements E21B 17/012, E21B 17/015)}

E21B 19/004 ・・{supporting a riser from a drilling or production platform}

E21B 19/006 ・・・{including heave compensators}

E21B 19/008 ・{Winding units, specially adapted for drilling operations (capstans, winches B66D; cathead actuated pipe wrenches or spinners E21B 19/162)}

E21B 19/02 ・Rod or cable suspensions (load-engaging elements for hoisting or lowering purposes in general B66C 1/00; Crown blocks or pulley blocks B66D; cable guides B66D 1/36)

E21B 19/04 ・・Hooks

E21B 19/06 ・・Elevators, i.e. rod or tube gripping devices

E21B 19/07 ・・・Slip-type elevators (slips E21B 19/10)

E21B 19/08 ・Apparatus for feeding the rods or cables (E21B 19/22 takes precedence; automatic feed E21B 44/02; hoisting drums B66D); Apparatus for increasing or decreasing the pressure on the drilling tool; Apparatus for counterbalancing the weight of the rods

E21B 19/081 ・・Screw-and-nut feed mechanisms

E21B 19/083 ・・Cam, rack or like feed mechanisms

E21B 19/084 ・・with flexible drawing means, e.g. cables

E21B 19/086 ・・with a fluid-actuated cylinder (E21B 19/084, E21B 19/087, E21B 19/09 take precedence)

E21B 19/087 ・・by means of a swinging arm

E21B 19/089 ・・with a spring or an additional weight

E21B 19/09 ・・specially adapted for drilling underwater formations from a floating support using heave compensators supporting the drill string (drilling-pipe telescoping joints E21B 17/07; {heave compensators for supporting a riser E21B 19/006})

E21B 19/10 ・Slips; Spiders; {Catching devices (rotary tables with master bushing or kelly bushing E21B 3/04; slip-type elevators E21B 19/07; casing heads with slips E21B 33/0422)}

E21B 19/12 ・Rope clamps (rope clamps in general F16G 11/00){rod, casings or tube clamps not secured to elevators}

E21B 19/14 ・Racks, ramps, troughs or bins, for holding the lengths of rod singly or connected; Handling between storage place and borehole (E21B 19/20, E21B 19/22 take precedence; {storing elongated articles in general B65G 1/0442})

E21B 19/143 ・・{specially adapted for underwater drilling}

E21B 19/146 ・・{Carousel systems, i.e. rotating rack systems}

E21B 19/15 ・・Racking of rods in horizontal position; Handling between horizontal and vertical position

E21B 19/155 ・・・{Handling between horizontal and vertical position}

E21B 19/16 ・Connecting or disconnecting pipe couplings or joints (E21B 19/20 takes precedence; Pipe wrenches or the like B25B)

E21B 19/161 ・・{using a wrench or a spinner adapted to engage a circular section of pipe (E21B 19/168 takes precedence)}

E21B 19/162 ・・・{cathead actuated}

E21B 19/163 ・・・{piston-cylinder actuated}

E21B 19/164 ・・・{motor actuated (E21B 19/162 and E21B 19/163 take precedence)}

E21B 19/165 ・・{Control or monitoring arrangements therefor}

E21B 19/166 ・・・{Arrangements of torque limiters or torque indicators}

E21B 19/167 ・・{using a wrench adapted to engage a non circular section of pipe, e.g. a section with flats or splines}

E21B 19/168 ・・{using a spinner with rollers or a belt adapted to engage a well pipe}

E21B 19/18 ・Connecting or disconnecting drill bit and drilling pipe

E21B 19/20 ・Combined feeding from rack and connecting, e.g. automatically

E21B 19/22 ・Handling reeled pipe or rod units, e.g. flexible drilling pipes {(lifting or hauling appliances using two or more cooperating endless chains B66D 3/003)}

E21B 19/24 ・Guiding or centralising devices for drilling rods or pipes

E21B 21/00 Methods or apparatus for flushing boreholes, e.g. by use of exhaust air from motor (freeing objects stuck in boreholes by flushing E21B 31/03; well drilling compositions C09K 8/02)

E21B 21/001 ・{specially adapted for underwater drilling}

E21B 21/002 ・{Down-hole drilling fluid separation systems (containers comprising collecting means with a strainer E21B 27/005; subsoil filtering E21B 43/02; down-hole production separators E21B 43/38)}

E21B 21/003 ・{Means for stopping loss of drilling fluid (plastering the borehole wall E21B 33/138)}

E21B 21/01 ・Arrangements for handling drilling fluids or cuttings outside the borehole, e.g. mud boxes ({swivel joints in hose-lines E21B 21/02;} arrangements for treating drilling fluids E21B 21/06; {waste disposal systems E21B 41/005})

E21B 21/012 ・・{using exhaust air from the drilling motor for blowing off the dust at the borehole entrance}

E21B 21/015 ・・Means engaging the bore entrance, e.g. hoods for collecting dust

E21B 21/02 ・Swivel joints in hose-lines {(hose connections in general F16L 31/00, F16L 33/00)}

E21B 21/06 ・Arrangements for treating drilling fluids outside the borehole (treating steps per se, see the relevant subclasses)

E21B 21/062 ・・{by mixing components}

E21B 21/063 ・・{by separating components}

E21B 21/065 ・・・{Separating solids from drilling fluids}

E21B 21/066 ・・・・{with further treatment of the solids, e.g. for disposal}

E21B 21/067 ・・・{Separating gases from drilling fluids}

E21B 21/068 ・・{using chemical treatment}

E21B 21/07 ・・for treating dust-laden gaseous fluids

E21B 21/08 ・Controlling or monitoring pressure or flow of drilling fluid, e.g. automatic filling of boreholes, automatic control of bottom pressure (valve arrangements therefor E21B 21/10)

E21B 21/10 ・Valve arrangements in drilling fluid circulation systems (valves in general F16K)

E21B 21/103 ・・{Down-hole by-pass valve arrangements, i.e. between the inside of the drill string and the annulus}

E21B 21/106 ・・{Valve arrangements outside the borehole, e.g. kelly valves}

E21B 21/12 ・using drilling pipes with plural fluid passages, e.g. closed circulation systems (pipes with plural fluid passages E21B 17/18)

E21B 21/14 ・using liquids and gases, e.g. foams

E21B 21/16 ・using gaseous fluids (E21B 21/14 takes precedence; arrangements for handling drilling fluids outside the borehole E21B 21/01; arrangements for treating drilling fluids E21B 21/06)

E21B 21/18 ・Preventing exhaust air from the drill motor from blowing-off towards the working face

E21B 23/00 Apparatus for displacing, setting, locking, releasing, or removing tools, packers or the like in the boreholes or wells (setting of casings, screens or liners E21B 43/10)

E21B 23/002 ・{Tool diverters, e.g. for through-the-flow line tool systems or for wire-line tools (E21B 23/03 takes precedence; for drilling E21B 7/06)}

E21B 23/004 ・{Indexing systems for guiding relative movement between telescoping parts of downhole tools}

E21B 23/006 ・・{"J-slot" systems, i.e. lug and slot indexing mechanisms}

E21B 23/01 ・for anchoring the tools or the like (E21B 23/02 to E21B 23/06 take precedence; anchoring of drives in the borehole E21B 4/18; {packers E21B 33/12})

E21B 23/02 ・for locking the tools or the like in landing nipples or in recesses between adjacent sections of tubing (E21B 23/03 to E21B 23/06 take precedence)

E21B 23/03 ・for setting the tools into, or removing the tools from, laterally offset landing nipples or pockets

E21B 23/04 ・operated by fluid means, e.g. actuated by explosion (E21B 23/06, E21B 23/08 take precedence)

E21B 23/06 ・for setting packers

E21B 23/065 ・・{setting tool actuated by explosion or gas generating means}

E21B 23/08 ・Introducing or running tools by fluid pressure, e.g. through-the-flow-line tool systems ({tool diverters E21B 23/002}; special provisions on heads therefor E21B 33/068; cementing plugs E21B 33/16; scrapers operated by fluid pressure E21B 37/04)

E21B 23/10 ・・Tools specially adapted therefor

E21B 23/14 ・for displacing a cable or cable-operated tool, e.g. for logging or perforating operations in deviated wells ({side entry sub E21B 17/02D; control line protectors E21B 17/1035}; by fluid pressure E21B 23/08; provision on well heads for introducing or removing cable-operated tools E21B 33/072, E21B 33/076)

E21B 25/00 Apparatus for obtaining or removing undisturbed cores, e.g. core barrels, core extractors (core bits E21B 10/02; using explosives or projectiles in boreholes E21B 49/04; side-wall sampling or coring E21B 49/06)

E21B 25/005 ・{Above ground means for handling the core, e.g. for extracting the core from the core barrel}

E21B 25/02 ・the core receiver being insertable into, or removable from, the borehole without withdrawing the drilling pipe (retrievable drill bits E21B 10/64)

E21B 25/04 ・・the core receiver having a core forming cutting edge or element, e.g punch type core barrels

E21B 25/06 ・the core receiver having a flexible liner or inflatable retaining means

E21B 25/08 ・Coating, freezing, consolidating cores (E21B 25/06 takes precedence); Recovering uncontaminated cores or cores at formation pressure

E21B 25/10 ・Formed core retaining or severing means (E21B 25/06, E21B 25/08 take precedence)

E21B 25/12 ・・of the sliding wedge type

E21B 25/14 ・・mounted on pivot transverse to core axis

E21B 25/16 ・for obtaining oriented cores

E21B 25/18 ・the core receiver being specially adapted for operation under water

E21B 27/00 Containers for collecting or depositing substances in boreholes or wells, e.g. bailers, {baskets or buckets} for collecting mud or sand; Drill bits with means for collecting substances, e.g. valve drill bits

E21B 27/005 ・{Collecting means with a strainer}

E21B 27/02 ・Dump bailers, i.e. containers for depositing substances, e.g. cement or acids

E21B 27/04 ・where the collecting or depositing means including helical conveying means {drilling with helical conveying means combined with bucket-type container E21B 7/006}

E21B 28/00 Vibration generating arrangements for boreholes or wells, e.g. for stimulating production (for drilling E21B 7/24; {for fishing for or freeing objects E21B 31/005}; for transmitting measuring-signals E21B 47/14; for geophysical measurements G01V 1/02)

E21B 29/00 Cutting or destroying pipes, packers, plugs, or wire lines, located in boreholes or wells, e.g. cutting of damaged pipes, of windows(perforatorsE21B 43/11); Deforming of pipes in boreholes or wells; Reconditioning of well casings while in the ground{(by enlarging drilled holes or counterboringE21B 7/28)}

E21B 29/002 ・{Cutting, e.g. milling, a pipe with a cutter rotating along the circumference of the pipe}

E21B 29/005 ・・{with a radially-expansible cutter rotating inside the pipe, e.g. for cutting an annular window}

E21B 29/007 ・・{with a radially-retracting cutter rotating outside the pipe}

E21B 29/02 ・by explosives or by thermal or chemical means ({freeing stuck objects by explosives E21B 31/002}; destroying objects in boreholes or wells by explosives E21B 31/16)

E21B 29/04 ・Cutting of wire lines or the like (E21B 29/02 takes precedence)

E21B 29/06 ・Cutting windows, e.g. directional window cutters for whipstock operations ({E21B 29/005 and}E21B 29/08 take precedence {(whipstocks E21B 7/061)})

E21B 29/08 ・Cutting or deforming pipes to control fluid flow (shear type blow-out preventers E21B 33/063)

E21B 29/10 ・Reconditioning of well casings, e.g. straightening

E21B 29/12 ・specially adapted for underwater installations (E21B 29/08 takes precedence)

E21B 31/00 Fishing for or freeing objects in boreholes or wells ({using junk baskets or the like E21B 27/00}; provisions on well heads for introducing or removing objects E21B 33/068; Locating or determining the position of objects in boreholes or wells E21B 47/09)

E21B 31/002 ・{Destroying the objects to be fished, e.g. by explosive means (cutting by explosives E21B 29/02)}

E21B 31/005 ・{using vibrating or oscillating means (vibration generating arrangements for boreholes or wells E21B 28/00)}

E21B 31/007 ・{fishing tools with means for attaching comprising fusing or sticking}

E21B 31/03 ・Freeing by flushing; {Controlling differential pipe sticking}

E21B 31/06 ・using magnetic means

E21B 31/107 ・using impact means for releasing stuck parts, e.g. jars (telescoping joints E21B 17/07)

E21B 31/1075 ・・{using explosives}

E21B 31/113 ・・hydraulically-operated

E21B 31/1135 ・・・{Jars with a hydraulic impedance mecanism, i.e. a restriction, for initially delaying escape of a restraining fluid}

E21B 31/12 ・Grappling tools, e.g. tongs or grabs

E21B 31/125 ・・{specially adapted for parted wire line or ropes}

E21B 31/14 ・・with means deflecting the direction of the tool, e.g. by use of knuckle joints (apparatus for deflecting the boring E21B 7/06)

E21B 31/16 ・・combined with cutting or destroying means (cutting or destroying means per se E21B 29/00)

E21B 31/18 ・・gripping externally, e.g. overshot

E21B 31/20 ・・gripping internally, e.g. fishing spears

E21B 33/00 Sealing or packing boreholes or wells

E21B 33/02 ・Surface sealing or packing

E21B 33/03 ・・Well heads; Setting-up thereof (valve arrangements therefor E21B 34/02)

E21B 33/035 ・・・specially adapted for underwater installations (E21B 33/043, E21B 33/064, E21B 33/076 take precedence)

E21B 33/0355 ・・・・{Control systems, e.g. hydraulic, pneumatic, electric, acoustic, for submerged well heads}

E21B 33/037 ・・・・Protective housing therefor

E21B 33/0375 ・・・・・{Corrosion protection means (in general C23F)}

E21B 33/038 ・・・・Connectors used on well heads, e.g. for connecting blow-out preventer and riser (connecting a production flow-line to an underwater well head E21B 43/013)

E21B 33/0385 ・・・・・{electrical connectors (underwater electrical connections in general H01R 13/523)}

E21B 33/04 ・・・Casing heads; Suspending casings or tubings in well heads (setting of casings in wells E21B 43/10)

E21B 33/0407 ・・・・{with a suspended electrical cable}

E21B 33/0415 ・・・・{rotating or floating support for tubing or casing hanger}

E21B 33/0422 ・・・・{a suspended tubing or casing being gripped by a slip or an internally serrated member (slips in rotary table E21B 19/10)}

E21B 33/043 ・・・・specially adapted for underwater well heads ({E21B 33/0407,}E21B 33/047 take precedence)

E21B 33/047 ・・・・for plural tubing strings

E21B 33/05 ・・・・Cementing-heads, e.g. having provision for introducing cementing plugs

E21B 33/06 ・・・Blow-out preventers, {i.e. apparatus closing around a drill pipe, e.g. annular blow-out preventers (rotating blow-out preventers E21B 33/085; valves E21B 34/00)}

E21B 33/061 ・・・・{Ram-type blow-out preventers, e.g. with pivoting rams}

E21B 33/062 ・・・・・{with sliding rams}

E21B 33/063 ・・・・・・{for shearing drill pipes (cutting of wireline E21B 29/04; cutting pipes E21B 29/08)}

E21B 33/064 ・・・・specially adapted for underwater well heads (connectors therefor E21B 33/038; {control systems for submerged well-heads E21B 33/0355})

E21B 33/068 ・・・having provision for introducing objects or fluids into, or removing objects from, wells (cementing heads E21B 33/05; {wipers, oil savers E21B 33/08})

E21B 33/072 ・・・・for cable-operated tools (E21B 33/076 takes precedence)

E21B 33/076 ・・・・specially adapted for underwater installations

E21B 33/08 ・・Wipers; Oil savers

E21B 33/085 ・・・{Rotatable packing means, e.g. rotating blow-out preventers}

E21B 33/10 ・in the borehole {sealing the junction between main bore and laterals E21B 41/0042}

E21B 33/12 ・・Packers; Plugs ({locking packers or plugs in landing nipples E21B 23/02}; used for cementing E21B 33/134, E21B 33/16)

E21B 33/1204 ・・・{permanent; drillable}

E21B 33/1208 ・・・{characterised by the construction of the sealing or packing means (E21B 33/1277 takes precedence)}

E21B 33/1212 ・・・・{including a metal-to-metal seal element}

E21B 33/1216 ・・・・{Anti-extrusion means, e.g. means to prevent cold flow of rubber packing}

E21B 33/122 ・・・Multiple string packers

E21B 33/124 ・・・Units with longitudinally-spaced plugs for isolating the intermediate space

E21B 33/1243 ・・・・{with inflatable sleeves}

E21B 33/1246 ・・・・・{inflated by down-hole pumping means operated by a pipe string}

E21B 33/126 ・・・with fluid-pressure-operated elastic cup or skirt (E21B 33/122, E21B 33/124 take precedence)

E21B 33/1265 ・・・・{with mechanical slips}

E21B 33/127 ・・・with inflatable sleeve (E21B 33/122, E21B 33/124 take precedence)

E21B 33/1272 ・・・・{inflated by down-hole pumping means operated by a pipe string}

E21B 33/1275 ・・・・{inflated by down-hole pumping means operated by a down-hole drive}

E21B 33/1277 ・・・・{characterised by the construction or fixation of the sleeve}

E21B 33/128 ・・・with a member expanded radially by axial pressure (E21B 33/122, , {E21B 33/129} take precedence; {characterised by the construction of the sealing means E21B 33/1208})

E21B 33/1285 ・・・・{by fluid pressure}

E21B 33/129 ・・・with mechanical slips for hooking into the casing (E21B 33/122, E21B 33/124 take precedence)

E21B 33/1291 ・・・・{anchor set by wedge or cam in combination with frictional effect, using so-called drag-blocks (E21B 33/1295 takes precedence)}

E21B 33/1292 ・・・・・{with means for anchoring against downward and upward movement}

E21B 33/1293 ・・・・{with means for anchoring against downward and upward movement (E21B 33/1291, E21B 33/1295 take precedence)}

E21B 33/1294 ・・・・{characterised by a valve, e.g. a by-pass valve}

E21B 33/1295 ・・・・actuated by fluid pressure

E21B 33/12955 ・・・・・{using drag blocks frictionally engaging the inner wall of the well}

E21B 33/13 ・・Methods or devices for cementing, for plugging holes, crevices, or the like (dump bailers E21B 27/02; {methods or apparatus for grouting offshore structures E02B 17/0008} chemical compositions therefor C09K 8/00)

E21B 33/134 ・・・Bridging plugs {(packers E21B 33/12)}

E21B 33/136 ・・・Baskets, e.g. of umbrella type

E21B 33/138 ・・・Plastering the borehole wall; Injecting into the formations {(packers E21B 33/12; consolidation of loose sand or the like round the wells without excessively decreasing the permeability thereof E21B 43/02B, compositions therefor C09K 8/56)}

E21B 33/14 ・・・for cementing casings into boreholes {(using special cement compositions E21B 33/13B; control of cementation quality or level E21B 47/0005)}

E21B 33/143 ・・・・{for underwater installations}

E21B 33/146 ・・・・{Stage cementing, i.e. discharging cement from casing at different levels}

E21B 33/16 ・・・・using plugs for isolating cement charge; Plugs therefor {(spacer compositions E21B 33/13B5; stage cementing E21B 33/146)}

E21B 34/00 Valve arrangements for boreholes or wells (in drilling fluid circulation systems E21B 21/10; {tool diverters E21B 23/002;} blow-out preventers E21B 33/06; oil flow regulating apparatus E21B 43/12; valves in general F16K)

E21B 34/02 ・in well heads

E21B 34/04 ・・in underwater well heads

E21B 34/045 ・・・{adapted to be lowered on a tubular string into position within a blow-out preventer stack, e.g. so-called test trees}

E21B 34/06 ・in wells

E21B 34/063 ・・{Valve or closure with destructible element, e.g. frangible disc (E21B 34/103 takes precedence)}

E21B 34/066 ・・{electrically actuated}

E21B 34/08 ・・responsive to flow or pressure of the fluid obtained (E21B 34/10 takes precedence)

E21B 34/085 ・・・{with time-delay systems, e.g. hydraulic impedance mechanisms}

E21B 34/10 ・・operated by control fluid supplied from above ground ({by a dropped ball or piston E21B 34/14;} above-ground control means E21B 34/16)

E21B 34/101 ・・・{with means for equalizing fluid pressure above and below the valve}

E21B 34/102 ・・・{with means for locking the closing element inopen or closed position (E21B 34/105 and E21B 34/108 take precedence)}

E21B 34/103 ・・・・{with a shear pin}

E21B 34/105 ・・・{retrievable, e.g. wire line retrievable, i.e. with an element which can be landed into a landing-nipple provided with a passage for control fluid}

E21B 34/106 ・・・・{the retrievable element being a secondary control fluid actuated valve landed into the bore of a first inoperative control fluid actuated valve}

E21B 34/107 ・・・・{the retrievable element being an operating or controlling means retrievable separately from the closure member, e.g. pilot valve landed into a side pocket (E21B 34/106 takes precedence)}

E21B 34/108 ・・・{with time delay systems, e.g. hydraulic impedance mechanisms}

E21B 34/12 ・・operated by movement of casings or tubings

E21B 34/125 ・・・{with time delay systems, e.g. hydraulic impedance mechanisms}

E21B 34/14 ・・operated by movement of tools, e.g. sleeve valves operated by pistons or wire line tools {(E21B 34/066 takes precedence)}

E21B 34/16 ・Above-ground control means therefor {(control systems for submerged well heads E21B 33/0355)}

E21B 35/00 Methods or apparatus for preventing or extinguishing fires (cutting or deforming pipes to control fluid flow E21B 29/08; controlling flow of fluid to or in wells E21B 43/12; fire fighting in general A62C, A62D)

E21B 36/00 Heating, cooling, insulating arrangements for boreholes or wells, e.g. for use in permafrost zones (drilling by use of heat E21B 7/14; secondary recovery methods using heat E21B 43/24)

E21B 36/001 ・{Cooling arrangements}

E21B 36/003 ・{Insulating arrangements}

E21B 36/005 ・{Heater surrounding production tube}

E21B 36/006 ・{Combined heating and pumping means}

E21B 36/008 ・{using chemical heat generating means}

E21B 36/02 ・using burners

E21B 36/025 ・・{the burners being above ground or outside the bore hole}

E21B 36/04 ・using electrical heaters

E21B 37/00 Methods or apparatus for cleaning boreholes or wells (E21B 21/00 takes precedence; {bailers E21B 27/00;} cleaning pipes in general B08B 9/02)

E21B 37/02 ・Scrapers specially adapted therefor

E21B 37/04 ・・operated by fluid pressure, e.g. free-piston scrapers (operating other tools by fluid pressure E21B 23/08)

E21B 37/045 ・・・{Free-piston scrapers}

E21B 37/06 ・using chemical means for preventing, limiting {or eliminating} the deposition of paraffins or like substances (chemical compositions therefor C09K 8/52)

E21B 37/08 ・cleaning in situ of down-hole filters, screens, {e.g. casing perforations,} or gravel packs (E21B 37/06 takes precedence)

E21B 37/10 ・Well swabs {(pistons in general F16J)}

E21B 40/00 Tubing catchers, automatically arresting the fall of oil-well tubing {(preventing small objects from falling into the borehole E21B 41/0021)}

E21B 41/00 Equipment or details not covered by groups E21B 15/00 to E21B 40/00

E21B 41/0007 ・{for underwater installations (E21B 41/005, E21B 41/04, E21B 41/06, E21B 41/08, E21B 41/10 take precedence)}

E21B 41/0014 ・・{Underwater well locating or reentry systems}

E21B 41/0021 ・{Safety devices, e.g. for preventing small objects from falling into the borehole}

E21B 41/0035 ・{Apparatus or methods for multilateral well technology, e.g. for the completion of or workover on wells with one or more lateral branches (whipstocks E21B 7/061; tool diverters E21B 23/002; cutting casing windows E21B 29/06; specific well pattern E21B 43/30)}

E21B 41/0042 ・・{characterised by sealing the junction between a lateral and a main bore}

E21B 41/005 ・{Waste disposal systems (treatment of drilling fluid outside the borehole E21B 21/06; collecting oil or the like from a submerged leakage E21B 43/0122)}

E21B 41/0057 ・・{Disposal of a fluid by injection into a subterranean formation}

E21B 41/0064 ・・・{Carbon dioxide sequestration (storing fluids in porous layers B65G 5/005)}

E21B 41/0071 ・・{Adaptation of flares, e.g. arrangements of flares in offshore installations (flares of waste gases or noxious gases F23G 7/08)}

E21B 41/0078 ・{Nozzles used in boreholes (drilling by liquid or gas jets E21B 7/18; drill bits with nozzles E21B 10/60; perforators using direct fluid action E21B 43/114; obtaining a slurry of minerals using nozzles E21B 43/29; nozzles in general B05B)}

E21B 41/0085 ・{Adaptations of electric power generating means for use in boreholes (generation of electric power per se H02)}

E21B 41/0092 ・{Methods relating to program engineering, design or optimisation}

E21B 41/02 ・in situ inhibition of corrosion in boreholes or wells (dump bailers E21B 27/02; chemical compositions therefor C09K 8/54; inhibiting corrosion in general C23F)

E21B 41/04 ・Manipulators for underwater operations, e.g. temporarily connected to well heads (manipulators in general B25J)

E21B 41/06 ・Work chambers for underwater operations, e.g. temporarily connected to well heads (in general B63C 11/00)

E21B 41/08 ・Underwater guide bases, e.g. drilling templates; Levelling therefor

E21B 41/10 ・Guide posts, e.g. releasable; Attaching guide lines to underwater guide bases

E21B 43/00 Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells (applicable only to water E03B; obtaining oil-bearing deposits or soluble or meltable materials by mining techniques E21C 41/00; pumps F04)

E21B 43/003 ・{Vibrating earth formations (vibration generating arrangements for boreholes or wells E21B 28/00)}

E21B 43/006 ・{Production of coal-bed methane (E21B 43/243 takes precedence; methods or devices for drawing-off gases for safety purposes in mines E21F 7/00)}

E21B 43/01 ・specially adapted for obtaining from underwater installations (underwater well heads E21B 33/035)

E21B 43/0107 ・・{Connecting of flow lines to offshore structures (E21B 43/013 takes precedence)}

E21B 43/0122 ・・{Collecting oil or the like from a submerged leakage (cleaning or keeping clear the surface of open water from oil or the like E02B 15/04)}

E21B 43/013 ・・connecting a production flow line to an underwater well head

E21B 43/0135 ・・・{using a pulling cable}

E21B 43/017 ・・Production satellite stations, i.e. underwater installations comprising a plurality of satellite well heads connected to a central station (underwater separating arrangements E21B 43/36)

E21B 43/02 ・Subsoil filtering (E21B 43/11TAKES precedence, chemical compositions for consolidating loose sand or the like around wells C09K 8/56)

E21B 43/025 ・・{Consolidation of loose sand or the like round the wells without excessively decreasing the permeability thereof (sealing borehole walls E21B 33/138)}

E21B 43/04 ・・Gravelling of wells

E21B 43/045 ・・・{Crossover tools}

E21B 43/08 ・・Screens or liners {(expandable screens or liners E21B 43/108; obtaining drinking water; filters E03B 3/18)}

E21B 43/082 ・・・{Screens comprising porous materials, e.g. prepacked screens}

E21B 43/084 ・・・{Screens comprising woven materials, e.g. mesh or cloth}

E21B 43/086 ・・・{Screens with preformed openings, e.g. slotted liners (comprising porous materials E21B 43/082)}

E21B 43/088 ・・・{Wire screens (comprising porous materials E21B 43/082; comprising woven materials E21B 43/084)}

E21B 43/10 ・・Setting of casings, screens, liners {or the like} in wells (driving or forcing casings into boreholes, simultaneously drilling and casing boreholes E21B 7/20; setting of tools, packers or the like E21B 23/00; suspending casings in well heads E21B 33/04)

E21B 43/101 ・・・{for underwater installations}

E21B 43/103 ・・・{of expandable casings, screens, liners, or the like}

E21B 43/105 ・・・・{Expanding tools specially adapted therefor}

E21B 43/106 ・・・・{Couplings or joints therefor}

E21B 43/108 ・・・・{Expandable screens or liners}

E21B 43/11 ・Perforators; Permeators

E21B 43/112 ・・Perforators with extendable perforating members, e.g actuated by fluid means

E21B 43/114 ・・Perforators using direct fluid action {on the wall to be perforated}, e.g. abrasive jets

E21B 43/116 ・・Gun or shaped charge perforators {(projectiles with shaped or hollow charge F42B 12/10)}

E21B 43/117 ・・・Shaped charge perforators (E21B 43/118 takes precedence)

E21B 43/118 ・・・characterised by lowering in vertical position and subsequent tilting to operating position

E21B 43/1185 ・・・Ignition systems

E21B 43/11852 ・・・・{hydraulically actuated}

E21B 43/11855 ・・・・{mechanically actuated, e.g. by movement of a wireline or a drop-bar (E21B 43/11852 takes precedence)}

E21B 43/11857 ・・・・{firing indication systems}

E21B 43/119 ・・Details, e.g. for locating perforating place or direction

E21B 43/1195 ・・・{Replacement of drilling mud; decrease of undesirable shock waves}

E21B 43/12 ・Methods or apparatus for controlling the flow of the obtained fluid to or in wells (E21B 43/25 takes precedence; valve arrangements E21B 34/00)

E21B 43/121 ・・{Lifting well fluids (survey of down-hole pump systems E21B 47/0007)}

E21B 43/122 ・・・{Gas lift}

E21B 43/123 ・・・・{Gas lift valves}

E21B 43/124 ・・・{Adaptation of jet-pump systems}

E21B 43/126 ・・・{Adaptations of down-hole pump systems powered by drives outside the borehole, e.g. by a rotary or oscillating drive (powered by fluid E21B 43/129)}

E21B 43/127 ・・・・{Adaptations of walking-beam pump systems}

E21B 43/128 ・・・{Adaptation of pump systems with down-hole electric drives}

E21B 43/129 ・・・{Adaptations of down-hole pump systems powered by fluid supplied from outside the borehole (gas-lift E21B 43/122; jet pumps E21B 43/124)}

E21B 43/14 ・Obtaining from a multiple-zone well

E21B 43/16 ・Enhanced recovery methods for obtaining hydrocarbons (fracturing E21B 43/26; obtaining slurry E21B 43/29; reclamation of contaminated soil in situ B09C; {chemical compositions therefor C09K 8/58})

E21B 43/162 ・・{Injecting fluid from longitudinally spaced locations in injection well}

E21B 43/164 ・・{Injecting C02 or carbonated water (in combination with organic material C09K 8/594)}

E21B 43/166 ・・{Injecting a gaseous medium; Injecting a gaseous medium and a liquid medium (CO2 injection E21B 43/164; steam injection E21B 43/24)}

E21B 43/168 ・・・{Injecting a gaseous medium}

E21B 43/17 ・・Interconnecting two or more wells by fracturing or otherwise attacking the formation ({E21B 43/2405,}E21B 43/247 take precedence)

E21B 43/18 ・・Repressuring or vacuum methods

E21B 43/20 ・・Displacing by water

E21B 43/24 ・・using heat, e.g. steam injection (heating, cooling or insulating wells E21B 36/00){(in combination with organic material E21B 43/22D)}

E21B 43/2401 ・・・{by means of electricity}

E21B 43/2403 ・・・{by means of nuclear energy (nuclear reactors G21)}

E21B 43/2405 ・・・{in association with fracturing or crevice forming processes (E21B 43/247 takes precedence)}

E21B 43/2406 ・・・{Steam assisted gravity drainage (SAGD)}

E21B 43/2408 ・・・・{SAGD in combination with other methods}

E21B 43/241 ・・・combined with solution mining of non-hydrocarbon minerals, e.g. solvent pyrolysis of oil shale

E21B 43/243 ・・・Combustion in situ

E21B 43/247 ・・・・in association with fracturing processes {or crevice forming processes}

E21B 43/248 ・・・・・using explosives

E21B 43/25 ・Methods for stimulating production (dump bailers E21B 27/02; vibration generating arrangements E21B 28/00; by vibrating earth formations E21B 43/00C] chemical compositions therefor C09K 8/60)

E21B 43/255 ・・{including the injection of a gaseous medium as treatment fluid into the formation}

E21B 43/26 ・・by forming crevices or fractures {(chemical compositions therefor C09K 8/62)}

E21B 43/261 ・・・{Separate steps of (1) cementing, plugging or consolidating and (2) fracturing or attacking the formation}

E21B 43/263 ・・・using explosives {(Combustion in situ using explosives E21B 43/248)}

E21B 43/2635 ・・・・{by means of nuclear energy (peaceful applications of nuclear explosive devices in generalG21J 3/00)}

E21B 43/267 ・・・reinforcing fractures by propping {(chemical compositions therefor C09K 8/80)}

E21B 43/28 ・Dissolving minerals other than hydrocarbons, e.g. by an alkaline or acid leaching agent (E21B 43/241 takes precedence; {using steerable or laterally extendable nozzles E21B 43/292})

E21B 43/281 ・・{using heat (heating, cooling or insulating wells E21B 36/00)}

E21B 43/283 ・・{in association with a fracturing process}

E21B 43/285 ・Melting minerals, e.g. sulfur (E21B 43/24 takes precedence; heating, cooling or insulating arrangements for wells E21B 36/00)

E21B 43/29 ・Obtaining a slurry of minerals, e.g. by using nozzles

E21B 43/292 ・・{using steerable or laterally extendable nozzles}

E21B 43/295 ・Gasification of minerals, e.g. for producing mixtures of combustible gases (E21B 43/243 takes precedence)

E21B 43/30 ・Specific pattern of wells, e.g. optimizing the spacing of wells (production satellite stations E21B 43/017)

E21B 43/305 ・・{comprising at least one inclined or horizontal well}

E21B 43/32 ・Preventing gas- or water- coning phenoma, i.e. the formation of a conical column of gas or water around wells

E21B 43/34 ・Arrangements for separating materials produced by the well (separating apparatus per se, see the relevant subclasses)

E21B 43/36 ・・Underwater separating arrangements (E21B 43/38 takes precedence)

E21B 43/38 ・・in the well

E21B 43/385 ・・・{by reinjecting the separated materials into an earth formation in the same well}

E21B 43/40 ・・Separation associated with re-injection of separated materials {(E21B 43/385 takes precedence)}

E21B 44/00 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 (for non-automatic drilling control, see the operation controlled; automatic feeding from rack and connecting of drilling pipes E21B 19/20; controlling pressure or flow of drilling fluid E21B 21/08; control systems in general G05); Systems specially adapted for monitoring a plurality of drilling variables or conditions (means for transmitting measuring-signals from the well to the surface E21B 47/12)

E21B 44/005 ・{Below-ground automatic control systems}

E21B 44/02 ・Automatic control of the tool feed ({E21B 44/005}, E21B 44/10 take precedence)

E21B 44/04 ・・in response to the torque of the drive; {Measuring drilling torque (E21B 44/06 takes precedence; measuring stresses in a well bore pipe E21B 47/0006)}

E21B 44/06 ・・in response to the flow or pressure of the motive fluid of the drive

E21B 44/08 ・・in response to the amplitude of the movement of the percussion tool, e.g. jump or recoil

E21B 44/10 ・Arrangements for automatic stopping when the tool is lifted from the working face {informative reference: arrangements for automatic stopping for portable percussive tools B25D 9/265}

E21B 45/00 Measuring the drilling time or rate of penetration

E21B 47/00 Survey of boreholes or wells (monitoring pressure or flow of drilling fluid E21B 21/08; geophysical logging G01V)

E21B 47/0001 ・{for underwater installations}

E21B 47/0002 ・{Survey of boreholes or wells by visual inspection (photographing internal surfaces, e.g. of pipes G03B 37/005, E21B57/A7B8; closed circuit television systems H04N 7/18)}

E21B 47/0003 ・{Determining well or borehole volumes (determining depth E21B 47/04, diameter E21B 47/08; measuring volumes in general G01F)}

E21B 47/0005 ・{control of cementation quality or level (measuring temperature E21B 47/065)}

E21B 47/0006 ・{Measuring stresses in a well bore pipe string or casing (for locating stuck pipe E21B 47/09)}

E21B 47/0007 ・{Survey of down-hole pump systems}

E21B 47/0008 ・・{Survey of walking-beam pump systems, e.g. for the detection of so called

E21B 47/01 ・Devices for supporting measuring instruments on a drill pipe, rod or wireline (setting or locking tools in boreholes or wells E21B 23/00); {(flexible centering means per se E21B 17/1014)} Protecting measuring instruments in boreholes against heat, shock, pressure or the like

E21B 47/011 ・・{Protecting measuring instruments (cooling or insulating arrangements for boreholes or wells E21B 36/00)}

E21B 47/02 ・Determining slope or direction (clinometers or direction meters G01C)

E21B 47/022 ・・of the borehole, {e.g. using geomagnetism}

E21B 47/02208 ・・・{using seismic or acoustic means}

E21B 47/02216 ・・・{using at least one source of electromagnetic energy and at least one detector therefor}

E21B 47/02224 ・・・・{at least one of the sources or one of the detectors being located above ground}

E21B 47/02232 ・・・{using a pendulum}

E21B 47/024 ・・of devices in the borehole (E21B 47/022 takes precedence)

E21B 47/026 ・・of penetrated ground layers (apparatus for obtaining oriented cores E21B 25/16; formation testing E21B 49/00)

E21B 47/04 ・Measuring depth or liquid level (measuring liquid level in general){and telerecorders for level of liquids}G01F; {measuring depth in general G01B 7/26}

E21B 47/042 ・・{Measuring or locating liquid level (E21B 47/044 takes precedence)}

E21B 47/044 ・・{using radioactive markers}

E21B 47/06 ・Measuring temperature or pressure (measuring temperature in general G01K; measuring pressure in general G01L){telerecorders for pressure G01L; telerecorders for temperature G01K}

E21B 47/065 ・・{Measuring temperature}

E21B 47/08 ・Measuring the diameter (measuring diameter in general G01B)

E21B 47/082 ・・{using radiant means, e.g. acoustic, radioactive, electromagnetic}

E21B 47/09 ・Locating or determining the position of objects in boreholes or wells, {e.g. the position of an extending arm}; Identifying the free or blocked portions of pipes (measuring depth E21B 47/04; measuring diameter E21B 47/08)

E21B 47/0905 ・・{by detecting magnetic anomalies (investigating materials by investigating magnetic variables G01N 27/72)}

E21B 47/091 ・・{by detecting an acoustic anomaly, e.g. a mud-pressure pulse}

E21B 47/0915 ・・{using impression packers, e.g. to detect recesses or perforations}

E21B 47/10 ・Locating fluid leaks, intrusions or movements {using impression packers E21B 47/0915; flow measurement in general G01F; examining density and leaking in general G01M}

E21B 47/1005 ・・{using thermal measurements (measurement temperature E21B 47/065)}

E21B 47/101 ・・{using acoustic energy}

E21B 47/1015 ・・{using tracers: using radioactivity}

E21B 47/102 ・・{using electrical indications: using light radiations}

E21B 47/1025 ・・{Detecting leaks, e.g. of tubing, by pressure testing (investigating fluid-tightness of structures by using fluid or vacuum G01M 3/02)}

E21B 47/12 ・Means for transmitting measuring-signals {or control signals} from the well to the surface {or from the surface to the well}, e.g. for logging while drilling (remote signalling in general G08)

E21B 47/121 ・・{using earth as an electrical conductor (E21B 47/122 takes precedence; in generalH04B 13/02 ; electric prospectingG01V 3/00)}

E21B 47/122 ・・{by electromagnetic energy, e.g. radio frequency (in general H04B magnetic propspecting G01V 3/00)}

E21B 47/123 ・・・{using light waves (optical transmission in general H04B 10/00; light guides, e.g. optical fibres G02B 6/00)}

E21B 47/124 ・・{Storing data down-hole, e.g. in a memory or on a record carrier (recording in connection with measuring in general G01D; information storage in general G11)}

E21B 47/14 ・・using acoustic waves

E21B 47/16 ・・・through the drill string or casing, {e.g. by torsional acoustic waves}

E21B 47/18 ・・・through the well fluid, {e.g. mud pressure pulse telemetry}

E21B 47/182 ・・・・{by continuous mud waves with modulation of the waves}

E21B 47/185 ・・・・{by negative mud pulses using a pressure relieve valve between drill pipe and annulus}

E21B 47/187 ・・・・{by positive mud pulses using a flow restricting valve within the drill pipe}

E21B 49/00 Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells (sampling in general G01N 1/00)

E21B 49/001 ・{specially adapted for underwater installations}

E21B 49/003 ・{by analysing drilling variables or conditions (E21B 49/005 takes precedence; Systems specially adapted for monitoring a plurality of drilling variables or conditions E21B 44/00)}

E21B 49/005 ・{Testing the nature of borehole walls or the formation by using drilling mud or cutting data (investigating chemical or physical properties of materials per se G01N)}

E21B 49/006 ・{Measuring wall stresses in the borehole (investigation of mechanical properties of foundation soil E02D 1/022)}

E21B 49/008 ・{by injection test; by analysing pressure variations in an injection or production test, e.g. for estimating the skin factor (measuring pressure E21B 47/06; obtaining fluid samples or testing fluids E21B 49/08)}

E21B 49/02 ・by mechanically taking samples of the soil (apparatus for obtaining undisturbed cores E21B 25/00; investigation of foundation soil in situ E02D 1/00)

E21B 49/025 ・・{of underwater soil, e.g. with grab devices (underwater coring E21B 25/18)}

E21B 49/04 ・・using explosives in boreholes; using projectiles penetrating the wall {drilling by use of explosives E21B 7/007; gun or shaped charge perforators E21B 43/116}

E21B 49/06 ・・with side-wall drilling tools {pressing} or scrapers

E21B 49/08 ・Obtaining fluid samples or testing fluids, in boreholes or wells {(packers E21B 33/12; valves E21B 34/00; analysing pressure variations in an injection or production test E21B 49/008)}

E21B 49/081 ・・{with down-hole means for trapping a fluid sample (E21B 49/10 takes precedence)}

E21B 49/082 ・・・{Wire-line fluid samplers (E21B 49/083 takes precedence)}

E21B 49/083 ・・・{Samplers adapted to be lowered into or retrieved from a landing nipple, e.g. for testing a well without removing the drill string}

E21B 49/084 ・・{with means for conveying samples through pipe to surface}

E21B 49/086 ・・{Withdrawing samples at the surface}

E21B 49/087 ・・{Well testing, e.g. testing for reservoir productivity or formation parameters}

E21B 49/088 ・・・{combined with sampling}

E21B 49/10 ・・using side-wall fluid samplers or testers

E21B 2003/00 Rotary drilling (drives used in the borehole E21B 4/00; rotary drilling machines in general B23B)

E21B 2003/02 ・Surface drives for rotary drilling

E21B 2003/05 ・・with a to-and-fro rotation of the drill pipe or casing

E21B 2010/00 Drill bits (specially adapted for deflecting the direction of boring E21B 7/064; with means for collecting substances E21B 27/00)

E21B 2010/08 ・Roller bits (roller core bits E21B 10/06; with leading portion E21B 10/26; characterised by wear resisting parts E21B 10/46)

E21B 2010/22 ・・characterised by bearing, lubrication or sealing details

E21B 2010/225 ・・・sealing details

E21B 2010/24 ・・・characterised by lubricating details

E21B 2010/243 ・・・・with drilling fluid supply to the bearing

E21B 2010/42 ・Rotary drag type drill bits with teeth, blades or like cutting elements, e.g. fork-type bits, fish tail bits (characterised by wear resisting parts E21B 10/54, by conduits or nozzles for drilling fluid E21B 10/60, by detachable or adjustable parts E21B 10/62)

E21B 2010/425 ・・characterised by teeth or cutter arrangement

E21B 2010/46 ・characterised by wear resisting parts, e.g. diamond inserts {(drill bits with self-renewable cutting edge E21B 10/006)}

E21B 2010/54 ・・the bit being of the rotary drag type, e.g. fork-type bits

E21B 2010/545 ・・・with blades having performed cutting elements mounted on a distinct support, e.g. polycrystalline inserts

E21B 2010/56 ・・Button type inserts (E21B 10/52 takes precedence)

E21B 2010/561 ・・・Inserts with performed cutting elements mounted on a distinct support, e.g. polycrystalline inserts

E21B 2010/562 ・・・・having a non planar or non circular cutting face

E21B 2010/563 ・・・・having a cutting face with different segments, e.g. mosaic-type inserts

E21B 2010/564 ・・・・characterised by support details

E21B 2010/565 ・・・・・Interface between the substrate and the cutting element

E21B 2010/566 ・・・・with chip breaking arrangements

E21B 2010/60 ・characterised by conduits or nozzles for drilling fluids (for roller bits E21B 10/18; for percussion drill bits E21B 10/38; {mining picks with arrangement of fluid-spraying nozzles E21C 35/187})

E21B 2010/607 ・・characterised by the nozzle structure

E21B 2010/62 ・characterised by parts, e.g. cutting elements, which are detachable or adjustable (E21B 10/64 takes precedence; for roller bits E21B 10/20; {for rotary drag type drill bits E21B 10/42}; for augers E21B 10/44)

E21B 2010/622 ・・with plural separable cutter elements

E21B 2010/624 ・・・independently attachable

E21B 2021/00 Methods or apparatus for flushing boreholes, e.g. by use of exhaust air from motor (freeing objects stuck in boreholes by flushing E21B 31/03; well drilling compositions C09K 8/02)

E21B 2021/005 ・using gaseous fluids

E21B 2021/006 ・Underbalanced techniques, i.e. where borehole fluid pressure is below formation pressure

E21B 2021/007 ・Arrangements for handling drilling fluids or cuttings outside the borehole, e.g. mud boxes

E21B 2021/008 ・・Means engaging the bore entrance, e.g. hoods for collecting dust

E21B 2021/06 ・Arrangements for treating drilling fluids outside the borehole (treating steps per se, see the relevant subclasses)

E21B 2021/061 ・・for treating dust-loaded gaseous fluids

E21B 2023/00 Apparatus for displacing, setting, locking, releasing, or removing tools, packers or the like in the boreholes or wells (setting of casings, screens or liners E21B 43/10)

E21B 2023/008 ・Self propelling system or apparatus, e.g. for moving tools within the horizontal portion of a borehole

E21B 2033/00 Sealing or packing boreholes or wells

E21B 2033/005 ・Sealings characterised by their shape

E21B 2033/10 ・in the borehole {sealing the junction between main bore and laterals E21B 41/0042}

E21B 2033/105 ・・characterised by sealing the junction between a lateral and a main bore

E21B 2034/00 Valve arrangements for boreholes or wells (in drilling fluid circulation systems E21B 21/10; {tool diverters E21B 23/002;} blow-out preventers E21B 33/06; oil flow regulating apparatus E21B 43/12; valves in general F16K)

E21B 2034/002 ・Ball valves

E21B 2034/005 ・Flapper valves

E21B 2034/007 ・Sleeve valves

E21B 2041/00 Equipment or details not covered by groups E21B 15/00 to E21B 40/00

E21B 2041/0028 ・Fuzzy logic, artificial intelligence, neural networks, or the like

E21B 2043/00 Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells (applicable only to water E03B; obtaining oil-bearing deposits or soluble or meltable materials by mining techniques E21C 41/00; pumps F04)

E21B 2043/01 ・specially adapted for obtaining from underwater installations (underwater well heads E21B 33/035)

E21B 2043/0115 ・・Drilling for or production of natural gas hydrate reservoirs; Drilling through or monitoring of formations containing gas hydrates

E21B 2043/12 ・Methods or apparatus for controlling the flow of the obtained fluid to or in wells (E21B 43/25 takes precedence; valve arrangements E21B 34/00)

E21B 2043/121 ・・{Lifting well fluids (survey of down-hole pump systems E21B 47/0007)}

E21B 2043/125 ・・・Adaptation of walking-beam pump systems

E21B 2049/00 Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells (sampling in general G01N 1/00)

E21B 2049/08 ・Obtaining fluid samples or testing fluids, in boreholes or wells {(packers E21B 33/12; valves E21B 34/00; analysing pressure variations in an injection or production test E21B 49/008)}

E21B 2049/085 ・・Determining specific physical fluid parameters