US 1660714 A
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Description (OCR text may contain errors)
Feb; 28; 1928.
R. A. LINCOLN ROTARY DRILLING APPARATUS Fil ed 'Aug'. 5. 1926 awe/ nto? R. z 'ncal/z Patented Feb. 28, 1928.
.'UNITED STATES OFFICE.
ROBERT A..LINCOLN, OF TONKAWA, OKLAHOMA, ASSIGNOR OF ONE-HALF TO AMERI- CAN IRON & MACHINE WORKS, INC., OF OKLAHOMA CITY, OKLAHOMA, A CORPORA- TION OF OKLAHOMA.
This invention relates to rotary drilling apparatus and more particularly to the man.- ner of constructing the drilling pipe for operating the drills of rotary drilling apparatus.
An im ortant object of the invention is to provi e in. rotary drilling apparatus a drill pipe permittingcirculation of the fluid in the usual manner, while at the same time maintainin a predetermined buoyancy, float-ing or ten ing to float the drill pipe, so that the operation of withdrawing or inserting the drill pipe is materially facilitated and'the pressure which is applied to the drill may be more closely regulated.
The invention relates more specifically to the construction of certain sections of the drill pipe to provide an air space which is constantly maintained during the operation of the drill and which accordingly provides a predetermined buoyancy, tending to support the drill. It will be obvious that with a structure of this character and by the insertion of a predetermined number of Ion ths of the especially constructed pipe, the weight of the pipe and drill being known and the depth of flu id within the hole being likewise known, the degree of pressure applied to the drill can be accurately determined.
vIn the accompanying drawings, wherein for the purpose of illustration a pr ferred embodiment of my invention is disclosed and wherein 2-.- Figure 1 is a vertical sectional view through a well embodying a drilling tube constructed in accordance withmy invention" Figure '2 is aiTenlarged vertical sectional view through one of the buoyant sectionsof the drill tubing;
Figure 3 is a section on the line 3-3 of Figure 2.
Referring now more particularly to the .drawings, the numeral 10 indicates-a rotary well drill and 11 the drill pipe thereof. This drill pipe is constructed in a plurality of sections, of which certain sections 12 are ordinary and the remaini sections, indicated at 13, are 'constructe in accordance with my invention. Each section 13 consists of an ordinary section of pipe within which is inserted. a section of pipe having a'smaller "diameter and indicated at 14. In addition to being of smaller diameter, the
ROTARY DRILLING APPARATUS.
Application-filed August 5, 1926. Serial No. 127,319.
pipe 14 is preferably of less length than the outer pipe section. At its upper end, this smaller pipe section is formed with a funnel.
dicated at 16. At its lower ehd, the smaller pipe is flared, as at 17, so that the perimeter of the largerportion of this flared section closely approaches the inner wall of the outer pipe, except through spaced extensions or lugs 17*, so that spaces 18 are left therebetween. The walls of the flare are further provided with openings 19. Sections of this type, when inserted within a'well, trap air in the chamber 20 formed between the inner and outer pipes and this trapped air tends to buoyantly support the pipe.
It will, of course, be obvious that the flare 17 could be omitted, if *so desired, but if this isdone, the lower end of the pipe 14 being unsupported would render the construction very fragile, which is, of course, an undesirable feature when the rough handling to which such pipes are subjected is taken into consideration. The flare 17, therefore, provides a support for maintaining the lower end of the pipe 14 in properly spaced relation to the walls of the drill p pe while the openings 18 and 19 provide a means for preventing collection of fluid within the space 20. While fluid 'will enter the space 20 in small quantities, as the device is lowered into the fluid of the well, it will, of course, be obvious that when the drill pipe is withdrawn, the fluid will drain therefrom and accordingly will not tend to corrode or destroy the inner pipe. If desired, the ends of the extensions or lugs 17 may be welded or otherwise secured to the pipe.
\ While 'I have above consistently referred to the device as a drill pipe, it Wlll, of course,
in the formation of well casings and the heavy pumping pressures will very probably wear through along its wall at some point during the operation. By making the chamber open-ended, the buoyancy is effected only by the lost air trapping space and whenthe pipe is withdrawn above the level of the water within the well, the section will immediately drain out any containedwater, so that'no extra weight need be lifted.
Since the construction hereinbefore set forth is capable of a certain range of change and modification without materially departing from the spirit of the invention, I do not limit myself to such s ecific structure except as hereinafter claime I claim 1. A floating drill pipe section comprising inner and outer tubes, the inner tube having an external diameter considerably less than the internal diameter of the outer tube whereby a "space is provided-therebetween, the upper end of the inner. tube being enlarged to engage the outer tube and secured andsealed thereto, the lower end of the in ner tube being flared and having the larger portions thereof extendin in close proximity to the inner face of the, wall of the outer tube, said flared portion of the inner tube being perforated. 2. A floating drill pipe section comprising inner and outer tubes, the inner tube having an external diameter considerably less than the internal diameter of the outer tube whereby a space is provided therebesignature.
inner tube beouter tube and the lower end tween, the upper end of the ing. enlarged to engage the secured and sealed thereto,
of the inner tube being flared and having the larger portions thereof extending in close proximity to the inner face of the wall of the outer tube, said larger portions of the lower end of the inner tube having ex-. tensions engaging the wall of the pipe.
lower end of the inner tube having exten- V sions engaging the wall of the pipe, said extensions being secured to the pipe.
4:. A floating drill pipe section comprising inner and outer tubes, the inner tube havin thin the internal diameter of the outer tube whereby a space is provided therebetween, the u per end of theinner tube being enlarge to engage the outer tube and secured and sealed thereto, the bore of the inner tube being in communication with the space between the tubes at the lower end of such space. I
In testimony whereof I hereunto afiix my ROBERT A. LINCOLN.
an external diameter considerably less