US 3390730 A
Description (OCR text may contain errors)
y 2, 1963 M. E. G. TECHY ETAL 3,390,730 APPARATUS FOR LINING A BOREHOLE AS A BORING BIT ADVANCES IN THE GROUND Filed Feb. 25, 1966 2 Sheets-Sheet 1 FIG 2 July 2, 1968 M. L. E. e.
' APPARATUS FOR LINING A TECHY ETAL 3,390,730
BOREHOLE AS A BORING IN THE GROUND 2 Sheets-Sheet Z BIT ADVANCES Fil ed Feb. 25, 1966 United States Patent Ofice 3,390,730 Patented July 2, 1968 6 Claims. (a. 175-171 ABSTRACT OF THE DISCLOSURE Apparatus for lining a borehole by inserting a lining element into the borehole in the wake of a boring bit. The bit is an eccentric member which can be inscribed in a circle of diameter d but which bores a hole of diameter d The lining element has an internal. diameter d greater than the diameter d in which the boring bit can be inscribed and an external diameter d, which is smaller than the hole diameter d such that the boring bit can penetrate easily into the hole already bored and the boring bit can be inserted in and withdrawn from the lining element.
Our invention relates to apparatus for lining a borehole as a boring bit advances in the ground.
Systems of this kind are necessary in cases where the ground being bored is a type which can cave in after the boring or drilling bit has passed, with consequent considerable difliculties in drilling; also, the lining must often be left behind in the borehole if the same is to be used permanently.
It is an object of this invention, inter alia in connection with deep holes, to solve the problem economically by means of a lining consisting of commercial tubes.
' In accordance with the invention there is provided apparatus for lining a borehole as a boring bit advances in the ground, said apparatus comprising a striking element having an eccentric boring bit which can be inscribed in a circle of diameter d and a lining whose internal diameter d is greater than the diameter al in which the boring bit can be inscribed and whose external diameter d is smaller than the hole diameter d in such a manner the lining can penetrate easily into the hole already bored and enable the boring bit to be inserted and withdrawn. The apparatus further comprises a vertical slideway on which two assemblies are movable, the first assembly comprising a first carriage and, mounted thereon, a motor for rotating a set of rods to whose lower end the striking element bearing the boring bit is connected, the second assembly comprising a second carriage, to which a motor is secured, and which is provided with a passage through which the rods, striking element and boring bit can pass, the second carriage having rigidly connected to it a lining element having secured at its lower end guide projections serving to keep the striking element correctly centered relative to the lining element.
The invention will be described with reference to the accompanying drawings which show an exemplary non-limitative embodiment.
In the drawings:
FIG. 1 is a diagrammatic view of the apparatus;
FIG. 2 is a view in enlarged scale of a portion of the apparatus in elevation and partly in section;
FIGS. 3-5 are views of details showing the boring operation and the member of use, and
FIGS. 3a, 4a, 5a are sections on the lines III-III, IVIV and V--V in FIGS. 3, 4 and 5 respectively.
The apparatus comprises a bearing frame 1 which can be, for instance, of the tracklaying kind and which can move along the ground and which has a vertical slideway 2 (FIGS. 1 and 2); two assemblies 3, 4 are vertically movable on the slideway 2. The assembly 3 comprises a carriage 5 having mounted thereon a motor 6 for driving an assembly of rods 7 having secured at its lower end a striking element formed by a striking hammer 8 having a boring bit 9 at its lower end. A reduced-diameter portion 8 narrower than the hammer 8 is provided between the hammer 8 and the boring bit 9. The motor 6 and striking element can be pneumatic, in which event they are supplied with compressed air by means of a compressor and air lines (not shown). The system formed by the elements 5-9 serves to bore holes in the ground; the assembly of rods 7 is rotated by the motor 6 and drives by its rotation the hammer 8 and the boring bit 9. The bit therefore experiences consecutive blows and a rotary movement.
The second system 4 comprises a carriage 10 on which a motor 11 is mounted and which also comprises a passage 12 through which the rods 7, element 8 and boring bit 9 can pass. A lining 13 formed of interconnected lining elements is rigidly connected to the carriage 10; guide projections 13 which are, as a rule, four in number are secured to the lower end of the lining 13 in order to maintain the striking element 8 in the correct concentric relationship relative to the lining elements of lining 13. The assemblies 3, 4 are raised and lowered by winches 14, 15 connected respectively to the carriage 5 by a chain 16 running over guide rollers 17, and to the carriage 10 by a chain running over guide rollers 19.
This invention is based on the following principle (FIG. 3):
The striker element in the form of hammer 8 having an eccentric boring bit 9 which can be inscribed in a circle of diameter d bores a hole of diameter d greater than the diameter d and the lining 13 has an internal diameter d greater than d and an external diameter d; smaller than d The lining 13 has the following capabilities:
(a) it can penetrate readily into the hole already bored,
(b) it enables the boring bit 9 to be inserted and withdrawn.
The operation is as follows:
The winches 14, 15 place the assemblies 3, 4 near the top of the slideway 2, as shown in FIG. 2. The various items, namely the lining element 13, rods 7, hammer 8 and boring bit 9 are brought to the position shown in FIG. 2. The boring bit 9 is rotated by the rods 7 (which are driven by the motor 6) and struck by the hammer 8 and thereby drills or bores a hole of diameter d (FIG. 3) in the ground. The lining element 13 of diameter d., is rotated by the motor 11 for ready penetration into the ground, penetration being made difficult by friction between the lining element 13 and the ground. The lining element 13 therefore penetrates readily into the ground in the wake of the boring bit 9.
Once the rods 7 and lining element 13 have completely penetrated into the ground, they are unscrewed from their drive devices and the carriages 5 and 10 with the motor 6, 11 are raised by the winches 14, 15. Fresh lining elements 13 and rods 7 are screwed to the drives and to the rods and lining elements already in the ground, and drilling can then continue.
When drilling is completed and it is required to leave the lining elements in the ground, the drilling elements are withdrawn as follows:
The lining-driving assembly 4 is now at the bottom of the slideway 2. The winch 15 of the assembly 3 raises a the rods 7 slightly until the hammer 8 is raised above the centering projections 13 (FIG. 4) of the driving element 13 and the projections 13 are opposite the part 8 The mechanism for rotating the rods 7 is then operated to shift the position of the boring bit 9 as shown in FIG. a so that the centering projections 13 take up a position in alignment with the recesses of the boring bit 9 so that the bit can enter the lining element 13 when it is raised by means of the winch 15 and the cables and pulleys 16, 17 (FIG. 5). Further withdrawal of the elements 79 is then effected by means of the winch 15 and cable 16.
To remvoe the lining elements 13, the rod-driving assembly 3 is first raised to the top of the slideway, whereafter the lining elements can be raised by means of the winch 14 and cable 18.
What we claim is:
1. Boring apparatus comprising a vertical slideway, first and second assemblies supported on the slideway for vertical movement, the first assembly comprising a carriage,
a rod assembly supported from said carriage, drive means 1 on said carriage coupled to said rod assembly for driving the same in rotation, and a striking element constituted as a hammer and an eccentric boring bit, said striking element being coupled to said rod assembly for undergoing rotation therewith, said boring bit being dimensioned such that it can be inscribed in a circle of diameter d whereas it generates a circle of diameter d to bore a hole of such diameter, said second assembly comprising a second carriage having a passageway through which the rod assembly, striking element and boring bit can pass, a lining element supported by said second carriage and second drive means on the second carriage for driving said lining element in rotation, said lining element encircling the rod assembly and hammer, the boring bit extending from the lining element during a boring operation, said lining element having an internal diameter d which is greater than the diameter d of the circle in which the boring bit can be inscribed, and an external diameter which is smaller than the diameter d of the hole bored by such bit under the conjoint action of the rotation of the rod assembly and the striking movement of the striking element whereby the lining element can readily pass through the bored hole and the bit can be inserted and withdrawn in the lining element, said lining element having a lower end and including guide projections thereat which cooperate with the striking element to maintain the same in centered relation within the lining element.
2. Apparatus as claimed in claim 1 comprising cables and winches coupled to the first and second assemblies to raise and lower the same along the slideway.
, 3. Apparatus as claimed in claim 1 comprising a hearing framework movable along the ground, said slideway being rigidly connected to said bearing framework for movement therewith.
4. Apparatus as claimed in claim 9 wherein said rod assembly and lining element are detachably connected to the first and second assemblies respectively whereby they may be decoupled and allowed to remain in the ground after a boring operation, whereupon the first and second assemblies can be raised and additional lining elements and rods coupled thereto and to the rod assesmbly and lining element in the ground whereafter boring can continue.
5. Apparatus as claimed in claim 4 comprising means coupled to the first and second assemblies to raise and lower the same along the slideway, said lining elements being removable from the bored hole by successively raising and lowering the second assembly and decoupling and removing the lining elements one by one.
6. Apparatus as claimed in claim 1 wherein said guide projections face inwardly and define an opening through which the bit is incapable of passing when the striking element is centered in the lining element, said striking element including a portion of reduced diameter between the bit and the hammer enabling the striking element to be raised to a position in which the portion of reduced diameter is disposed in the opening defined by the guide projections and the hammer is above the guide projections and free thereof whereby the striking element can be shifted laterally in the lining element and the bit withdrawn past the guide projections,
References Cited UNITED STATES PATENTS 1,869,892 8/1932 Grove -171 X 2,784,942 3/1957 Peck 175-171 2,979,143 4/1961 Kandle 175-171 X 3,190,378 6/1965 Davey 175-171 X NILE C. BYERS, JR., Primary Examiner.