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
  • E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
• • 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
  • E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
  • E21B17/02—Couplings; joints
  • E21B17/04—Couplings; joints between rod or the like and bit or between rod and rod or the like
  • E21B17/042—Threaded
• • 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
  • E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
  • E21B17/16—Drill collars

Definitions

• This invention pertains to drill string components such as used in the oil, gas, water and mining industry, and especially to components thereof employing the use of a fishing neck at the pin end thereof to retain fishability, the employment thereof in a pin up direction also enhancing the bending strength ratio (BSR) of the drill string and dimensionally permitting the use of larger, stronger connections.
• BSR bending strength ratio
• D Outside diameter of pin and box
• d Inside diameter of bore
• b Thread root diameter of box threads at the end of pin
• R Thread root diameter of pin threads
• the bending strength ratio does not depend on the outside diameter or the inside diameter of the body of the tool members, but only with respect to the respective dimensions at the box and pin, or the dimensions at the connection ends of the members.
• the grapple When picking up the fish, the grapple is contracted by the tapers in the bowl, thus engaging the teeth more as the pull is increased.
• the overshot fishing tool can be released by jarring down to disengage the taper on the grapple from the taper in the bowl, then slowly rotating the overshot to the right while pulling up.
• Washover is the process that is begun by the running into the hole of several joints of flush joint casing with an inside diameter slightly larger than the fish and an outside diameter less than the diameter of the hole. Washover pipe is then run into the hole on the drill pipe and the fish is milled over, also cutting and washing the formation away from the fish in an attempt to free the fish so it can be retrieved with an overshot fishing tool, as described above.
• the BSR increases as the pin inside diameter increases while the BSR decreases quite rapidly as the box outside diameter decreases.
• Another feature of the invention permits the use of a larger, stronger connection with an acceptable BSR; for example, NC 40/4" F.H., 51 ⁇ 4" O.D. x 21 ⁇ 2" I.D., with a BSR of 2.30:1 and over 30% increase in torsional strength.
• a structure in a drill string component is provided so as to maintain a high bending strength ratio in the drill string connections for situations when relatively small hole sizes made it necessary in the prior art to run small drill string components with a low BSR.
• a "drill collar” and a “drill pipe” are generic names for a length or joint of a tubular product intended for inclusion in a drill string of such products.
• Normal lengths of drill pipe as well as these special lengths are all referred to generically as drill collars and drill pipe.
• Such lengths of pipe are also referred to as "rotary subs”.
• the drill string component disclosed herein is designed to be included in the drill string with its pin end up.
• the body portion of the component joins the box portion at one end and the pin portion at the other.
• the box portion has either the same outside diameter as the body portion or a larger outside diameter than the body portion.
• the box portion has a larger outside diameter than the body portion.
• the pin section has a larger diameter than the body portion but the pin section is smaller than the outside diameter of the box portion.
• the pin section includes a so-called "fishing neck" adjacent the pin, which means that its outside diameter is smaller than the outside diameter of the box portion.
• Figure 1 is a longitudinal sectional view of a preferred embodiment of a pair of interconnected drill collars in accordance with the present invention
• Figure 1A is a longitudinal sectional view of an alternative embodiment of a drill collar in accordance with the present invention.
• Figure 1B is a longitudinal sectional view of a preferred embodiment of a drill pipe in accordance with the present invention.
• Figure 1C is a longitudinal sectional view of a stabilizer in accordance with the present invention.
• a drill collar comprises three portions or sections, namely, a body section 12, which runs the majority of the length of the overall drill collar 10, a box section 14 and a pin section having a pin end 16.
• the box section is the female part of the connection and the pin section is the male part of the connection.
• the pin section is pointed up in hole 18.
• a fishing neck 20 Located below pin end 16 is a fishing neck 20.
• body section 12 Located below fishing neck 20 is body section 12.
• the shoulder of the pin at outside bevel diameter 22 has to be adequate to carry the torsional load applied to the connection.
• This shoulder width is initially machined at a bevel diameter of 4-37/64", 4-49/64", and 4-61/64", respectively, for corresponding with 4-3/4 O.D., 5" O.D., and 5-1/4" O.D. box dimensions.
• the pin strength does not change due to a change in its outside diameter as long as an adequate shoulder width is maintained.
• the box and pin sections are both relatively short in length compared with the body section.
• the body section is usually on the order of 28 feet in length and the end sections are usually on the order of 18"-24" in length.
• the section of the drill collar shown in the drawing referred to as fishing neck 20 is normally a minimum of 18" in length.
• the entire body section 12A may be of the same outside diameter of the fishing neck 20A.
• the BSR applies to the rotary shouldered connection or the threads connecting the drill string components, with the outside diameter of the box primarily controlling the bending strength ratio.
• the outside diameter of the pin section and the outside diameter of the body can be reduced without reducing the bending strength ratio.
• the larger outside diameter of the box section needs to be only a few inches in length, i.e., sufficient in length to strengthen the box threaded connection. A sufficient length to allow the box connection to be reworked several times is normally used.
• the body section diameter is the same as or less than the diameter of the pin section, as shown in the case of body section 12B of drill pipe 10B of Figure 1B, the body section can be washed over without milling off any steel. Or, the structure described above and shown in the figure 1 can be left alone and at a larger dimension than if the box end were up, to provide weight and stiffness.
• the reduced pin section allows the fishing overshot to engage the fish, as discussed above.

Landscapes

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

Priority Applications (9)

Applications Claiming Priority (2)

Publications (1)

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ID=25426738

Family Applications (1)

Country Status (19)

Cited By (13)

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Citations (5)

Family Cites Families (7)

• 1986
  • 1986-09-19 US US06/909,164 patent/US4760889A/en not_active Expired - Lifetime
  • 1986-12-11 IN IN904/CAL/86A patent/IN168972B/en unknown
• 1987
  • 1987-08-31 CA CA000545707A patent/CA1256094A/en not_active Expired
  • 1987-09-02 DE DE3790534A patent/DE3790534C2/de not_active Expired - Fee Related
  • 1987-09-02 KR KR1019880700554A patent/KR930004021B1/ko not_active IP Right Cessation
  • 1987-09-02 WO PCT/US1987/002195 patent/WO1988002056A1/en active IP Right Grant
  • 1987-09-02 HU HU874778A patent/HU206757B/hu not_active IP Right Cessation
  • 1987-09-02 EP EP87906137A patent/EP0324756B1/en not_active Expired - Lifetime
  • 1987-09-02 AT AT0905587A patent/AT394089B/de not_active IP Right Cessation
  • 1987-09-02 JP JP62505558A patent/JPH01501406A/ja active Granted
  • 1987-09-02 BR BR8707821A patent/BR8707821A/pt not_active IP Right Cessation
  • 1987-09-02 AU AU79664/87A patent/AU590183B2/en not_active Ceased
  • 1987-09-02 NL NL8720473A patent/NL192346C/nl not_active IP Right Cessation
  • 1987-09-02 DE DE873790534T patent/DE3790534T1/de active Pending
  • 1987-09-14 CN CN87106383A patent/CN1009122B/zh not_active Expired
• 1988
  • 1988-05-18 DK DK271888A patent/DK168165B1/da not_active IP Right Cessation
  • 1988-05-18 NO NO882176A patent/NO174218C/no not_active IP Right Cessation
• 1989
  • 1989-02-24 RU SU894613558A patent/RU1836535C/ru active
  • 1989-03-07 GB GB8905125A patent/GB2219022B/en not_active Expired - Lifetime
• 1992
  • 1992-07-30 SG SG777/92A patent/SG77792G/en unknown

Patent Citations (5)

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