Electropulse method of holes boring and boring machine

• US 6,164,388 A
• Filed: 04/07/1999
• Issued: 12/26/2000
• Est. Priority Date: 10/14/1996
• Status: Expired due to Fees

• Current Assignee: ITAC Limited
• Original Assignee: ITAC Limited
• Inventors: Martunovich, Adam Albert, Fedorovich, Vajov Vyacheslav
• Primary Examiner(s): PEZZUTO, ROBERT ERIC
• Application Number:
  US09/284,833
• Time in Patent Office: 629 Days
• Field of Search: 175/1, 175/15, 175/16, 175/17, 175/67, 166/249, 166/65.1, 166/177.1, 299/14, 299/16, 299/17
• US Class Current: 175/1
• CPC Class Codes: E21B 7/15 of electrically generated heat
• CPC Class Codes: E21B 7/18 Drilling by liquid or gas jets, with or without entrained pellets E21B7/14 takes precedence

Abstract

This invention provides an excavator 1 for crushing a matter to be excavated, existing in an excavating hole in which a discharge liquid is fed, by electric discharge between a plurality of electrodes generated by high-voltage pulses. The excavator comprises a high-voltage pulse generator 2; a plurality of electrodes 17, 18, at least one of which is given a high voltage from the high-voltage pulse generator 2; discharge liquid circulating system 3, 4, 5a, 5b; and optimum condition setting devices 13, 14, 15, 16. Also, this invention provides an excavation method in which at least one of the parameters for excavation efficiency of i) load voltage required for crushing the matter to be excavated; ii) single pulse energy; and iii) quantity of discharge liquid, is optimized for minimization of power consumption required for excavation by using the excavator of this invention.

Claims

1. An excavation method for crushing a matter to be excavated, existing in an excavating hole in which a discharge liquid is fed, by means of electric discharge between a plurality of electrodes generated by high-voltage pulses, characterized in that at least one of the following parameters for excavation efficiency is set to be an optimum value for minimization of power consumption required for excavation, before performing the excavation:

i) load voltage required for crushing said matter to be excavated;

ii) single pulse energy; and

iii) quantity of discharge liquid.

2. An excavation method as set forth in claim 1, wherein an optimum value of said load voltage required for crushing said matter to be excavated is found by varying said load voltage continuously or intermittently within a range of load voltages including a load voltage value U1 given by the following Equation:

space="preserve" listing-type="equation">U1=K(1/n-1).sup.0.15 ×

U.sub.0 ×

L.sup.0.4 [kv] (1)

Where

K;

a coefficient, K=1.0-1.5 [1/cm⁰.4 ];

n;

the number of electrodes;

L;

a length between the electrodes [cm]; and

U₀ ;

a value obtained by testing, or a voltage [kv] applied when a sample of the matter to be excavated existing in said discharge liquid is crushed via two electrodes having the length of 1 cm therebetween placed on said sample.

3. An excavation method as set forth in claim 1, wherein an optimum value of said single pulse energy is found by varying said single pulse energy continuously or intermittently within a range of single pulse energies including a single pulse energy W₀ given by the following Equation:

space="preserve" listing-type="equation">W.sub.0 >

90L.sup.1.6 [J] (2)

4. An excavation method as set forth in claim 1, wherein an optimum value of said quantity of discharge liquid is found by varying said quantity of discharge liquid continuously or intermittently within a range of quantity of discharge liquid including quantity Q of discharge liquid given by the following Equation:

space="preserve" listing-type="equation">Q=(0.25-0.5)π

×

Db.sup.2 /4×

f [liter/min.] (3)

Where

Db;

a diameter of a bore top [cm]; and

f;

the number of pulses per second (frequencies of pulse).

5. An excavator 1 for crushing a matter to be excavated, existing in an excavating hole in which a discharge liquid is fed, by means of electric discharge between a plurality of electrodes generated by high-voltage pulses, said excavator comprising:

a high-voltage pulse generator 2;

a plurality of electrodes 17, 18, at least one of which is given a high voltage from said high-voltage pulse generator 2;

discharge liquid circulating system 3, 4, 5a, 5b; and

optimum condition setting devices 13, 14, 15, 16,

said optimum setting devices 13, 14, 15, 16 being connecting between said high-voltage pulse generator 2 and said plurality of electrodes 17, 18, or assembled in said discharge liquid circulating system 3, 4, 5a, 5b, or connected between said high-voltage pulse generator 2 and said plurality of electrodes 17, 18 and assembled in said discharge liquid circulating system 3, 4, 5a, 5b, so that at least one of the following parameters for excavation efficiency is optimized so that power consumption required for excavation can be minimized;

i) load voltage required for crushing said matter to be excavated;

ii) single pulse energy; and

iii) quantity of discharge liquid.

6. An excavator 1 for crushing a matter to be excavated, existing in an excavating hole in which a discharge liquid is fed, by means of electric discharge between a plurality of electrodes generated by high-voltage pulses, said excavator comprising:

a high-voltage pulse generator 2;

a plurality of electrodes 17, 18, at least one of which is given a high voltage from said high-voltage pulse generator 2; and

a bore pipe 11, including a high-voltage pipe 20 and a ground pipe 21 arranged concentrically outside of said high-voltage pipe 20, for conveying said high voltage to said electrodes between said high-voltage pulse generator 2 and said plurality of electrodes 17, 18, said bore pipe being connected to said high-voltage pulse generator 2 at one end portion thereof and connected to said plurality of electrodes at the other end portion thereof,

wherein an inside of said ground pipe 21 and an outside of said high-voltage pipe 20 of said bore pipe 11 are plated with a non-magnetic and high conductive material.

7. An excavator 1 for crushing a matter to be excavated, existing in an excavating hole in which a discharge liquid is fed, by means of electric discharge between a plurality of electrodes generated by high-voltage pulses, said excavator comprising:

a high-voltage pulse generator 2;

a plurality of electrodes 17, 18, at least one of which is given a high voltage from said high-voltage pulse generator 2;

a bore pipe 11, connected to said high-voltage pulse generator 2 at one end portion thereof and to said plurality of electrodes at the other end portion thereof, for conveying said high voltage to said electrodes between said high-voltage pulse generator 2 and said plurality of electrodes 17, 18; and

a guide 10, arranged around said bore pipe 11, for guiding said bore pipe 11 into underground,

said bore pipe 11 and said guide 10 being connected with each other through a sliding contact point 23 so that said bore pipe 11 can slide vertically within said guide 10.

8. An excavator 1 for crushing a matter to be excavated, existing in an excavating hole in which a discharge liquid is fed, by means of electric discharge between a plurality of electrodes generated by high-voltage pulses, said excavator comprising:

a high-voltage pulse generator 2; and

a plurality of electrodes 17, 18 at least one of which is given a high voltage from said high-voltage pulse generator 2,

wherein said high-voltage electrodes 18 and other electrodes 17 to which said high voltage is input are bent at their ends so that one can extend toward the other with respect to each other.

9. An excavator 1 for crushing a matter to be excavated, existing in an excavating hole in which a discharge liquid is fed, by means of electric discharge between a plurality of electrodes generated by high-voltage pulses, said excavator comprising:

a high-voltage pulse generator 2;

a plurality of electrodes 17, 18, at least one of which is given a high voltage from said high-voltage pulse generator 2;

a vertically extending bore pipe 11, connected to said high-voltage pulse generator 2 at one end portion thereof and to said plurality of electrodes at the other end portion thereof, for conveying said high voltage to the electrodes between said high-voltage pulse generator 2 and said plurality of electrodes 17, 18; and

a lifting device having a lifting means for moving said bore pipe 11 up and down,

wherein a high-voltage input portion 9 for inputting a high voltage to said bore pipe 11 is arranged at one end portion of said bore pipe 11 inclined from an axis of said bore pipe 11 at a predetermined angle α

.

10. An excavator 1 for crushing a matter to be excavated, existing in an excavating hole in which a discharge liquid is fed, by means of electric discharge between a plurality of electrodes generated by high-voltage pulses, said excavator comprising:

a high-voltage pulse generator 2;

a plurality of electrodes 17, 18, at least one of which is given a high voltage from said high-voltage pulse generator 2; and

a bore pipe 11, including a high-voltage pipe 20 and a ground pipe 21 arranged concentrically outside of said high-voltage pipe 20, for conveying said high voltage to said electrodes between said high-voltage pulse generator 2 and said plurality of electrodes 17, 18, said bore pipe being connected to said high-voltage pulse generator 2 at one end portion thereof and to said plurality of electrodes at the other end portion thereof,

wherein an outer surface of a high-voltage input portion 9 for inputting said high voltage to said bore pipe 11 is coated with a semi-conductive material and is electrically connected with said ground pipe 21.

11. An excavator 1 for crushing a matter to be excavated, existing in an excavating hole in which a discharge liquid is fed, by means of electric discharge between a plurality of electrodes generated by high-voltage pulses, said excavator comprising:

a high-voltage pulse generator 2;

a plurality of electrodes 17, 18, at least one of which is given a high voltage from said high-voltage pulse generator 2;

a bore pipe 11, connected to said high-voltage pulse generator 2 at one end portion thereof and to said plurality of electrodes at the other end portion thereof, for conveying said high voltage to said electrodes between said high-voltage pulse generator 2 and said plurality of electrodes 17, 18; and

a discharge mud collecting device fixed to said bore pipe 11,

wherein said discharge mud collecting device has discharge liquid feeding passageways 32a, 32b which are formed by pipes having a segment section and arranged concentrically with said bore pipe 11; and

collecting passageways 33a, 33b which are formed by grooves defined between said discharge liquid feeding passageways 32a, 32b and in which a plurality of elastic valves 37 are arranged along a direction of said discharge mud being collected.

12. An excavator 1 for crushing a matter to be excavated, existing in an excavating hole in which a discharge liquid is fed, by means of electric discharge between a plurality of electrodes generated by high-voltage pulses, said excavator comprising:

a high-voltage pulse generator 2;

a bore top 12 having a plurality of electrodes 17, 18 at least one of which is given a high voltage from said high-voltage pulse generator 2; and

a bore pipe 11, having one end portion to which said high-voltage pulse generator 2 is connected and the other end portion to which said bore top 12 is threadedly fixed, for conveying said high voltage to said electrodes between said high-voltage pulse generator 2 and said bore top 12,

wherein a threaded portion of the bore top 12 is provided with a horizontally extending aperture 38 having a predetermined length and two detents 39a, 39b arranged in said horizontally extending aperture 38, and wherein a length between said two detents 39a, 39b is rendered shorter than said predetermined length of the horizontally extending aperture 38, in order to allow said bore top 12 to rotate around its axis.

13. An excavator 1 for crushing a matter to be excavated, existing in an excavating hole in which a discharge liquid is fed, by means of electric discharge between a plurality of electrodes generated by high-voltage pulses, said excavator comprising:

a high-voltage pulse generator 2;

a bore top 12 having a plurality of electrodes 17, 18 at least one of which is given a high voltage from said high-voltage pulse generator 2; and

a bore pipe 11, having one end portion to which said high-voltage pulse generator 2 is connected and the other end portion to which said bore top 12 is connected, for conveying said high voltage to said electrodes between said high-voltage pulse generator 2 and said bore top 12,

wherein said bore top 12 is provided with said electrodes at points of intersection of grid and is movable in said excavating hole.