US2007666A - Water-tight telescopic kelly - Google Patents

Description

July 9, 1935. E. A. SMITH WATER-TIGHT TE LESCOPIC KELLY Filed Oct. 14, 1933 5 Sheets-Sheet l INVENTOR YM ATTORNEYS- E. A. SMITH 2,

WATER-TIGHT TELESCOPIG KELLY Filed Oct. 14, 1933 3 Sheets-Sheet 2 July 9, 1935.

F IG. 2.

Jufly 9, 1935. E. A. SMITH WATER-TIGHT TELESCOPIC KELLY s Shets-Sheet 5 Filed Oct. 14, 1933 WKM INVENTOR a/w. 4 ATTORNEYS Patented July 9, 1935 WATER-TIGHT TELESCOPE} KELLY Edward A. Smith, Chatham,-NJJ., assignor, by mesne assignments, to CaissonOontracting Company, New York, N. Yea corporation of Delaware i Application. Qctober 14, 1933, Serial No. 693,532 4 Claims. (GL255-e-19) This invention pertains to ing holes in the ground. l

In the use of apparatus of the kind shown-in Powell Patent N 0. 1,654,600 or in Hart'and Schroeapparatus f or drillnish'fluid to the cutting tool, and it has been customary to supply the fluid, usually water,

through the hollow drill shaft. The shaft heretofore used has usually comprised an upper seclo tion in the form of a hollow drill stem splined to slide vertically through the drive gear, or rotary, and a lower section consisting of lengths of steel pipe bolted end to end with flanged watertight joints. h

The operation of drilling a hole with a drill shaft of the above kind is substantially asfollows:

,1.' Bolt the drill to flange at bottom of drill stem. V

2. Drill hole drillstem; r V

3. Pull up drill stem and drill by means of a hoisting cable until the flange at bottom of drill stem is above the rotary. r

4..Su pport the drill by suitable clamps, turn oil, the water, unbolt the drill stem and lay it aside. r v

5. Pick up the first length of drill pipe and bolt one end of it to the drill. v p

f V 6. Pick up the first length of drill pipe, together with'the drill, release clamps, lower drill pipe and drill until upper flange of drill pipe is just above the rotary and hold it there with clamps. I

7. Pick up the drill stem and bolt it to the top' 3; of the first length of drill pipe. Y

I 8., Pick up the drill stem, the first length of drill pipe and the drill as a unit, release the clamps,

lower the above drill pipeassembly'and drill into the hole, turn on the water and continue drilling. 9. Drill an additional depth depending on the length of the first section of drill pipe. a

10. Pull the assembly up again, add a second length of drill pipe by the sameprocess as outlined above for the, first length lower the drill 45 and the drill pipe assembly into the hole again and resume drilling.

It will be noted that each time thehole is deepened by the length of a section of drill pipe it becomes necessary to go'through a decidedly 0 time-consuming operation to add additional drill pipe before drilling can be continued to greater depth.-

But the time lost in the actual operations in- 20 to depth'permitted by length of volved in adding the drillpipe as described above 55 isnot the wholestory. While the drill is inoperder Patent No. 1,931,845 it is necessary to fur any necessary repairs. :removing the drill and lowering it again into the hole requires so much time that the superintendation, the water, fed under pressure to the drill, circulates upwardly through the mud above the drill, thereby agitating the mud and keeping the solid matter in suspension. In going through the operations described above to increase the lengthbf the drill shaft, it is necessary to With,- draw the drill from the hole and shut off the water 'circulation, thus stopping the agitation of the mud laden fluid. Then so much time is consumed in the operation of lengthening the drill shaft that by the time the drill is again lowered into the hole, much of the coarse material has settled to the bottom" of the hole underneath the drill. It follows that after each section of drill pipe has been added, it is usually necessary to re-drill a considerable distance in order to get thedrill' down to the level to which it had previously penetrated. f

After the hole has been drilled to the required depth it becomes necessary to unbolt and remove the drill pipe, section by section, in order to bring the drill back to the surface of the ground. It is found in'a'ctual practice that about half of the total time used in drilling a hole in the above manner ,is consumed in adding and removing the drill pipe sections as described above.

In' addition to the actual time consumed in adding orremoving sections of drill stem, there is another serious disadvantage in the use of drill shafts'of the above type. It often happens that the drilling operation may progress normally for some time and then slow up. This change in drilling speed may be due to a change in the character of I the ground, in which case nothing can be done about it. On the other hand, it may be due to broken teeth on the drill or to a'plu'gg'ed passage or other difficulties with the drill barrel. At such a time'it would'be very desirable'to be able to bring the drill or drill barrel to the surface of the ground ior inspection and for making However, the process of ent on the job will usually take a chance on the "bit or drill being in poor condition rather thanface a' certain loss of time involved in bringing it to the surface for inspection, with the result that drilling or coring may proceed at a much slower rate than necessary. Furthermore, the hole may :on occasion be drilled under-size due to the fact that some of the teeth on the drill have broken off. An under-sized hole must, in many cases, be

jre-drilled'beforethe casing can be inserted. V

An object of the present invention is to over} come the above'shortcomings by providing a drill load to the bit. In the case of the telescopic,

kelly heretofore used with rotary excavating buckets, the entire weight of the kelly is available for feedload while the bucketis operating near the surface of the ground. As the depth of the hole increases, the sections of kelly areone' by one supported by the rotary so that when the bucket approaches the maximum depth, the feedload is reduced to the weight of the bucket,

plus the weight of the lowest section of the kelly.

One method of overcoming this shortcoming of the ordinary telescopic 'kelly' is by locking the kelly sections together as disclosed in Smith Patent No. 1,895,901. The present invention utilizes both the pressure and weight of the fluid within the kelly to exert a downward pressure or feedload on the drill.

Further and other objects and advantages will be apparent from thefspecification and claims, and from the accompanying drawings which illustrate what is now considered the preferred embodiment of the invention. e

Fig. 1 is a diagrammatic showingof the apparatus with a Powell type drill and three kelly sections fully extended, the upper section having moved partially through the rotary.

Figs. 2 and 2A taken together showian enlarged cross-section of the kelly fully telescoped,

Fig. 3 is a cross-section on line3-3 of Fig. 2A.

Referring to Fig. 1, ID designates a drill of'the Powell type having a hollow hub l2, and flange l4 by which it is bolted to flange I 6 at the bottom of lower kelly section [8. Kelly'section l8 telescopes into section 20 above it, which in turn telescopes into the upper and outer section 22. I

The upper section-22' is driven by rotary 24 through splines 26 on the outside of section 22. Internal keys 28 at the bottom'of section 22 drive section 20 through splines'30 on section 20. In like manner section 20 drives section I8 through keys 32 and splines 34 (Fig. 3) To simplify the drawings, splines 30 and 34 are not shown in Figs. 2 and 2A. f f f Water is supplied to the interior of the kelly by hose 36 through swivel 38 fasten the top of upper kelly section 22.

Cable 40 passes downwardly into the kelly through stufiing box 42, its lower end being connected to the bottom of the innermost and lowest kelly section l8' through swivel 44, spindle 46, spider 48 and bolts 50. An air pocket 52 is formed in the upper part of airtight skirt 54 of the swivel, thus keeping the bearings of the swivel out 01 contact with the water in the kelly. Cable 40 is available for telescoping the kelly and -for controlling (to a certain extent) the feedload on the drill.

A tube 56 is provided inswivel 38 to guard the cable from abrasion by 'the'water or' its contents.

The apparatus is mounted on a crane having a table 58 to support the rotary 24 and a boom 60 to support the head sheave 62. U V

The upper end of section I 8 (Fig. 2) is provided with an external ring of resilient packing 64 and a leather cup-ring 66, both bearing against the inner surface of section 20, to prevent passage of fluid from the interior of the kelly outwardly between sections l8 and 20. In like manner, outward passage of fluid between sections 20 and 22 is prevented by resilient ring 68 and cup leather 10 at the top of section 2%]. Rings 12 and 14, adjustable by screws 16 and 18, provide adjustments for resilient rings 64 and 68, respectively.

A split collar 80 is clamped around the lower end of outer section 22 (Figs. 1, 2A and 3).

When it is desired to sink a hole in the ground by the above apparatus, the drill is placed over the selected spot, with the kelly resting on the drill, asshown in Figs. 2 and 2A, except that the water 82 has not yet been turned on. Dry

drilling can then be done by rotating gear 24,

all of the kelly sections being available as a feed load for the drill. However, when the kelly is filled with water under a pressure sufficient for the requirements of the drill, the upward pressure against head 84 of the outer kelly section will raise the outer section 22 until collar 80 encounters thrust bearing 86 on the rotary, as indicated by the dotted line position in Fig. l, and will remain there until the kelly is fully extended, after which collar 80 will leave bearing 86 and the upper kelly section will follow the others downwardly, as indicated in Fig. 1.

So long as collar 80 is in contact with thrust bearing 86 the downward reaction of the thrust against bearing 86 is available as feed-load on the drill, the minimum value of this reaction being measured by the'pressure of the fluid per unit area, and by the internal diameter, or rather the internal cross sectional area of the kelly section next above the section attached to the drill. During this stage of the drilling operation the feed load is a combination of the water pressure, weight of water within the kelly, and weight of a portion of the kelly itself.

After collar 80 leaves bearing 86 the pressure no longer reacts downwardly on the drill, therefore the feed load then consists principally of the weight of the kelly and its contents.

It is to be understood that the invention is not limited to the specific embodiment herein illustrated and described, but may be used in other ways without departure from its spirit as defined by the-"following claims. I

1. In an apparatus of the class described, an earth boring tool, a kelly for actuating said tool, said kelly comprising a plurality of splined sections telescoped within one another to'rotate as a unit, each section being of smaller diameter than the next preceding section, means for feeding fluid through said kelly to said tool, and means for preventing leakage of the fluid between the sections of the kelly.

2. In an apparatus of the class described, an earth boring tool, a kelly for actuating said tool, said kelly comprising a plurality of splined sections telescoped within one another to rotate as a unit, each section being of smaller diameter than the next preceding section, means for feeding fluid through said kelly to said tool, and means comprising resilient packing between said kelly sections for preventing the passage of fluid therebetween.

3. In an apparatus of the class described, an earth boring tool, a kelly for actuating said tool, said kelly comprising a plurality of splined sections telescoped within one another to rotate as a unit, each section being. of smaller diameter than the next preceding section, means for feeding fluidthrough said kelly to said tool, means for preventing leakage of the fluid between the sections of the kelly, and means for preventing upward movement of the upper section of said kelly, whereby the pressure of: the fluid reacting downwardly from said upper section serves as a feedload on said tool.

4. In an apparatus of the class described, an earth boring tool, a kelly for actuating said tool, said kelly comprising a plurality of splined sections telescoped within one another to rotate as a unit, each section being of smaller diameter than the next preceding section, and means for supplying liquid to the interior ofsaid kelly, whereby said liquid serves as a feedload on said tool.

EDWARD A. SMITH.

Images