US 3217816 A
Description (OCR text may contain errors)
Nov. 16, 1965 BQYER METHOD OF REMOVING PIPE Original Filed Sept. 7, 1962 .N-Q-t h- \Q g |u INVENTOR Louis B. Boyer BY W W Ma ATTORNEYS United States Patent Ufifrce 3,217,816 Patented Nov. 16, 1965 3,217,816 METHOD OF REMOVING PIPE Louis B. Boyer, 9531 N. Green Court, Westrninister, Colo. Continuation of application Ser. No. 221,976, Sept. 7, 1962. This application Dec. 10, 1964, Ser. No. 419,274 3 Claims. (Cl. 175-57) This application is a continuation of my copending application, Serial No. 221,976, filed September 7, 1962, now abandoned.
This invention relates to a masonry drill and more in particular to a drill for removing pipe from a wall.
Heretofore it has been necessary to remove a large section of the wall to remove therefrom a pipe which has broken close to or flush with the wall surface. Attempts to drill in masonry from around the exterior surface of the pipe have not been satisfactory, because of the excessive chattering, which usually leads to the rupture of the pipe wall.
The tool described herein is a rotary tool and does not operate on the percussion principle employed in removing drill stems, as shown in the Sitton et a1. Patent No. 2,827,264; neither does it operate on the same principle as a core bit, such as used in drilling oil wells. Masonry drills, as shown in the Chapin Patent No. 2,856,157 and Tilden Patent No. 2,506,474 are not suitable for removing pipes from a masonry wall.
Very often in new construction, or in domestic installation a surface pipe will become broken at the point of entry to the wall and there will be no access to the waterproofing on the outside 'of the wall. It will therefore become desirable to remove this pipe from the only point of access.
It is an object of the present invention to provide a tool which will remove a pipe from a masonry wall.
It is a further object of this invention to provide a drilling bit which will not only remove a small section of the wall adjacent the pipe but remove a small amount of the surface of the pipe.
It is a still further object of this invention to provide a drilling bit that may be operated by a standard electric drill.
The various features of novelty which characterize the present invention are pointed out with particularity in the claims annexed to and forming a part of this specification. However, for a better understanding of the invention, and its advantages and specific objects in the use thereof, reference is made to the accompanying drawings and descriptive matter wherein is illustrated and described a preferred embodiment of the invention.
In the drawings:
FIGURE 1 is a schematic view of the invention, showing the drill bit and the wall.
FIGURE 2 is a side view, partially in section, showing the bit.
FIGURE 3 is an end view of the bit shown in FIG URE 1.
FIGURE 4 is a view, partially in section, showing the bit and the wall with the pipe in place.
A drill bit is composed of a barrel section 11 having teeth 12, 12, around the end circumference thereof and having a shank portion 13 on its opposite end.
The teeth may be made of hardened steel or of cemented carbide, and are fixed to the barrel section around the leading end thereof. These teeth may be set with a pitch or rake angle 9, shown in FIGURE 3 of 0 to 8 degrees to aid in their cutting action. The slank or trailing end portion 13 may be threaded or may be welded to the barrel portion 11 and has a stud 14 on the end thereof of such a diameter that it may be received by a standard electric drill. The inside diameter of the bit is smaller than the pipe by 10 to 20 mils, so that the interior cutting surface 15 of the teeth 12 remove the exterior surface of the pipe 16. This acts as a guide and prevents chattering of the tool when the exterior surface 17 and the end surface 18 of the teeth 12 come into contact with the masonry wall 19. This permits a smooth even cut of the tool through the wall and the removal of the pipe 16 therefrom when the wall has been breached.
In operation, the tool 10 is fixed to the electric drill 20 by means of the stud 14 being received in and held by the chuck 21. The drill is then brought into contact with the pipe 16, as shown in FIGURE 1. The interior surface of the drill teeth mill the pipe and the pipe acts as a guide for the drill bit, which when advanced along the pipe, as shown in FIG. 4 mills the wall 19 from around the pipe.
A drill bit for use on a three-fourth inch pipe is one and seven-sixteenth inches outside diameter and can vary from twelve to forty-eight inches in length. The inside diameter of the cutting teeth as pointed out above is slightly less than the outside diameter of the pipe so as to remove therefrom 10 to 20 mils of the pipe wall.
While in accordance with provisions of the statutes, there has been illustrated and described the best form of embodiment of this invention now known, it will be apparent to those skilled in the art that changes may be made in the form or size "of the apparatus disclosed without departing from the spirit of this invention as set forth in the appended claims and that in some cases certain features of the invention may be used to advantage without a corresponding use of other features.
What is claimed is:
1. A method of removing a pipe embedded in a masonary wall which comprises the steps of:
(a) contacting said wall with said pipe embedded therein, at the point at which said pipe is embedded in said wall, with a rotary drill bit having an axial bore and a plurality of elongated cutting teeth which extend substantially along the interior and exterior surfaces of said bit at the leading end thereof and which are rigidly attached to said leading end of said bit, said cutting teeth having an interior diameter of from 10 to 20 mils less than the outside diameter of said pipe, and an outside diameter greater than the outer diameter of said bit and an inner diameter less than the inner diameter of said bit, said cutting teeth having a pitch of 0 to 8 degrees, said bit being attached at the trailing end thereof to a rotary tool;
(b) moving said drill bit coaxially of said pipe so as the axial bore of said drill bit from the breach in bit using said pipe as a guide means for guiding the movement of said drill bit into said wall and coaxially of said pipe in such a manner as to remove from 10 to 20 mils of the exterior surface from such pipe during the drilling operation; and
(c) removing said drill bit with said pipe contained in the axial bore of said drill bit from the breach in said wall when said drilling operation has been completed.
2. A method as claimed in claim 1 wherein said cutting teeth are tool steel.
' 3. A method as claimed in claim 1 wherein said cutting teeth are cemented carbide.
4!- Kraus 175403 X Sheiburne 77-69 Tilden 175-403 X Phipps 175-403 Stcfies 175403 X Thatcher 175-94 CHARLES E. OCONNELL, Primary Examiner.