WO2015054720A1

WO2015054720A1 - A portable and disposable apparatus and method for rapid measurement of water level and blast hole depth

Info

Publication number: WO2015054720A1
Application number: PCT/AU2014/000913
Authority: WO
Inventors: Gary Cavanough
Original assignee: Qmr (Ip) Pty Ltd
Priority date: 2013-10-17
Filing date: 2014-09-16
Publication date: 2015-04-23
Also published as: AU2018241169B2; AU2018241169A1; AU2014336947B2; AU2014336947A1

Abstract

A portable and disposable apparatus for rapidly measuring the depth of blast holes and water levels including a disposable vessel filled with material to weight the vessel. The vessel adapted to lowered into a blast hole at the end of a cord from means to dispense the cord and record the depth at which water in the hole or the bottom of the hole, causes immediate deceleration of the vessel and the temporary and/or sustained release of tension in the cord and wherein, the cord is cut post measurement and disposed of with the vessel in the hole.

Description

A PORTABLE AMD DISPOSABLE APPARATUS AND METHOD FOR RAPID MEASUREMENT OF WATER LEVEL AND BLAST HOLE DEPTH

FIELD OF THE INVENTION

The invention relates to the mining and construction industry and is particuiariy but not limited to a portable and disposable apparatus for rapidly measuring the depth and water levels of blast holes primarily concerned with drilling and mining operations.

BACKGROUND TO THE INVENTION

Prior art measurement of blast hole depth after drilling has been completed is performed by feeding a measuring line into the hole. For blast holes depth measurement it is normal practice to use a tape measure with a weight attached to the end of the tape. Both total hole depth and water depth are recorded in addition to assigning the hole an identification number. This process in known as "dipping" and is a two or more person task with as many as two thousand holes being dipped for a single blast. One or more persons is required to operate the tape measure whiie another person records the measurements. This information is used to determine if the hole has collapsed and the type of explosives to be used for the particular hole.

The use of non "weight on a string" solutions are fraught with difficulties due to the hole's relativeiy narrow diameter, non vertical orientation, the coarse and irregular surfaces of the hole and the muddiness of water in the hole. These are major challenges that have eliminated a number of potential technologies in the application to bore hole measurement. Examples of which include the small hole diameter limiting ability for ultrasound to propagate, muddy water preventing penetration of laser light, non vertical and non straight holes causing instruments lowered into hole to be caught on the wall of the hole and mud clogging up instruments that are dropped and recovered from the hole.

Furthermore the requirement of a number of operators using current methods to dip a bore hole is a costly expense. Prior art equipment is also limited in its application and the presence of mud in the bottom of blast holes can dilute blasting agents causing misfires or low order detonation. There is therefore a need for a portable and disposable one man operable device that may also include a facility to penetrate and recover a sample of mud that may be at the bottom of the hole. Some examples of the prior art include devices disclosed in WO 2011/047440 A1 (IGUANA INDUSTRIAL SOLUTIONS PTY. LTD.) and CN 202109869 U (INNER MONGOLIA KANGNING BLASTING CO. LTD.).

CN 202109869 U is a utilit model patent that discloses a simple plumb bob suspended on a wire rope to measure the depth of a blast hole. There also appears to be some facility to measure water levels in the blast hole, however this involves replacing the plumb bob with a special water height detection probe of less density than water. It does not appear to be a disposable device.

WO 2011/047440 A1 discloses a highly specialised device on which a line with a weight is released and retracted on a rotatable reel and wherein the line is fed through a hollow elongate leader. The measurement of blast hole water level is via a float assembly movable relative to the line. The line carries a weight which pulls the line through the float. The float includes a float sensor, a reed switch for detecting when a magnet on the weight is in close proximity to or is separated from the float. Essentially, this device is a complex electronic apparatus which relies on the distance between the magnet and the sensor to obtain depth measurements. Unlike the device of CN 202109869 U, there is no requirement to replace the weigh and float arrangement wit a special water height detection probe, however in common with C 202109869 U, it is also not a disposable device, it is therefore an object of the present invention to seek to ameliorate or eliminate one or more limitations or disadvantages of the prior art by providing a portable and disposable apparatus for rapidly measuring the depth of blast holes and water levels and to provide the public with a useful choice.

SUMMARY OF THE INVENTION

In one aspect, the invention resides in a portable and disposable apparatus for rapidly measuring the depth of blast holes and water levels in the same including in combination:

a disposable vessel adapted to be filled with a material to weight the vessel;

the vessel adapted to lowered into a blast hole at the end of a cord;

the vessel having a wide base wherein contact with water in the hole causes immediate deceleration of the vessel and temporary release of tension in the cord, and wherein contact with the bottom of the hole causes a sustained release of tension in the cord; cord length measuring and dispensing means to dispense the cord and record/measure the depth at which water in the hole or the bottom of the hole, causes immediate deceleration of the vessel and the temporary and/or sustained release of tension in the cord;

and wherein,

the dispensed cord is cut post measurement and disposed of with the vessel in the hole and a replacement vessel is attaGhed to end of the freshly cut cord for measuring the next blast hole.

Preferably, the cord length measuring and dispensing means comprises

a spool on which the cord is wound and unwound;

the spool adapted to release the card vertically into a blast hole;

a magnetic brake and measurement pulley assembly in contact with the cord to determine the length of the cord unwound from the spool wherein deceleration of th vessel and release of tension in the cord is detected as a measurement of depth.

Preferably, the vessel is a disposable plastic vessel adapted to be filled with drill cuttings usually comprising rocks to weight the vessel.

Preferably, the vessel has a substantially frusta-conical shape with a wide flat base wherein contact with water in the hole causes immediate deceleration of the vessel More preferably the vessel has a concave or a cup-shaped base wherein on contact with water in the ^'hole, the configuration of the base causes immediate deceleration of the vessel.

In a preferred example, the vessel may also include a disposable mud sampling spear to sample and measure the depth of mud in the bottom of the hole wherein the cord is retracted to record the mud sampte and depth measurements before cutting and disposing of the cord and vessel in the hole.

Preferably, the cord is disposable cord such as fishing line but may be of another suitable disposable material.

Preferably, ther is a global positioning system (GPS) associated with the apparatus to identify the location of the blast hole.

Preferably, there is computer recording means to record the GPS position and depth of the water level and the blast hole measured by the apparatus.

Preferably, depth information from the cord length measuring and dispensing means and GPS information is data logged on the computer recording means via keyboard or may be semi automated by pressing a button on a programmable logic controller (PLC) device. in another aspect the invention resides in a method of measuring the depth of b!ast holes and water levels using the apparatus hereinabove described including- the steps of:

(a) towering a weighted vessel attached to a cord from the cord length measuring and dispensing means into a blast hole;

(b) measuring the length of the cord released from the cord length measuring and dispensing means as a measurement of depth;

(c) recording via computer recording means the depth at which the vessel comes into contact with any water or when the vessel bottoms at the base of the hole, together with the GPS location of the blast hole;

(d) taking a mud sample from the bottom of the blast hole if the vessel includes a mud sampling spear;

(e) cutting and disposing of the dispensed cord and the vessel in the hole, and

(f) attaching a replacement vessel to the end of the freshly cut cord for measuring the next blast hole.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the invention be better understood and put into practise, reference is made to the accompanying drawings wherein:

Figure 1 illustrates the uploading of hole identification numbers to the computer recording means.

Figure 2 illustrates the use of GPS to find hole numbers in the vicinity of the apparatus. Figure 3 illustrates a disposable plastic vessel filled with drill cuttings and attached to the cord.

Figure 4 illustrates the spool and cord measuring assembly

Figure 5 illustrates locating water in the blast hole.

Figure 6 illustrates locating the bottom of the blast hole.

Figure 7 illustrates cutting and recovery of the cord.

DETAILED DESCRIPTION OF THE DRAWINGS

According to the present invention the method provides for recording a hole identification number for the depth of the hole measured. The method may include all hole numbers being recorded in the computer recording means at some time earlier. The apparatus preferably has an inbuilt Global Position System (GPS) that is used to determine the hole identifications numbers that are in close proximity to the apparatus itself. The operator can preferably not only identify but also select the appropriate identification number of the hole to be measured.

The operator takes a disposable plastic vessel prior filled with heavy material or fills the vessel with drill cuttings. Drill cuttings are rock fragments that are produced during drilling and normally deposited at the top of the hole. The invention utilises a disposable cord such a fishing line but it can be another material that is attached to the piastic vessel using a piastic clip. The method of attachment for the reusable vessel is b preferably by wrapping the cord around two offset plastic clips and for the disposable vessel is by wrapping the cord around the clip and pushing the clip into holes that have been previously made in the wall of the plastic vessel. An additional option Is a sampling spear attached to the base of the plastic vessel. This spear is preferably 400mm in length and penetrates and retains a sample of mud that ma be in the bottom of the hole.

The plastic vessel is dropped into the hole with the operator periodically pulling up on the cord to prevent/or clear the vessel being lodged on the wall of the hole. When the vessel hits water the operator will observe a sudden decrease in acceleration of the vessel due to the shape of its base (e.g. such as in the case of a flat or concave base, the vessel is instantl stopped by the water surface) and the operator holds the line and may move the cord up and down to confirm the vessel is at the top of the water. Where the apparatus is semi-automated in operation by a PLC device, a button is pressed to cause the invention to record the length of cord to the surface of the water. Naturall the vessel will become infiltrated with water over a period of time and begin to sink to the bottom of the hole with the tension in the cord gradually returning. The vessel is released by the operator and the pulling up procedure is repeated until the vessel settles on the bottom of the hole wherein the release of tension is sustained. Again a button is pressed to record the length of cord. The apparatus calculates the total hole depth and water depth using the measurements of the cord and stores this information and the particular hole identification number as located by the GPS. At some later time the data is downloaded from the computer recording means to drilling reporting software.

When a disposable plastic vessel is used, on completion of each measurement, the cord is cut and left in the hole with the plastic vessel. In cases where a reusable plastic vessel is used the cord is recovered using a fast rotating spool and then discarded on the surface adjacent to the hole. When the piastic vessel s recovered and the sampling spear is present the operator can also identify and measure the depth of mud in the bottom of the hole

A more detailed description will now be provided with reference to the accompanying figures, it will be appreciated that the detailed description is intended to provide details of preferred features of the invention and should, not be construed as limiting on the invention in any way. In the drawings:

Figure 1 illustrates the uploading of hole identification numbers to the computer recording means. A computer 10 holds a file containing the unique hole identification number and the GPS location coordinates for the hole. The fife is transmitted to the apparatus 12 of the invention and stored in the computer recording means.

Figure 2 illustrates the use of GPS to find hole numbers in the vicinity of the apparatus 12. The accuracy of the GPS location is limited and current technology does not allow sufficient resolution to identify individual holes 14, 16, 18. 20; consequently the invention uses a local and internal GPS receiver to determine current hole location. Preferably, all hole identification numbers within ten metres of this location are displayed. The operator selects the hole identification numbe of th hole to be measured.

Figure 3 illustrates a disposable plastic vessel 22 filled with drill cuttings 24 and attached to the cord 26. To remove the necessity to carry weig hts that are required for the vessel to be dropped into a hole, a light weight piastic vessel is used for this purpose, The vessel is filled with drill cuttings and attached to the cord using a plastic cli 28. The vessel is filied with heavy material and preferably sealed, The preferred method of attachment is by wrapping the cord around two plastic clips located on opposite sides of the vessel.

Figure 4 illustrates the spool and cord measuring assembly. The cord 26 is stored inside the invention on a spool 30 and is threaded through a magnetic brake/measurement pulley assembly 32, The brake ensures the measurement assembly is always in contact with the cord to provide length measurement when the immediate deceleration of the vessel and release of tension in the cord is detected as a measurement of depth.

Figure 5 illustrates locating water 34 in the blast hole. Gravity causes the vessel 22 filled wit cuttings to fall towards the bottom of the hole 36. The operator maintains a light grip on the cord 26 as it is fed into the hole. The operator moves the cord up and down if the cord stops moving to ensure the vessel has not lodged on the sid of the hole. When the vessel meets the water surfac it with stop momentarily due the resistance of the flat bottom 22a of the vessel 22 before penetrating the water surface 34a. The operator will hold and pull and drop the cord to confirm the water surface 34a and press a button on a PLC device {not shown) of the invention to indicate the cord is at the water surface.

Figure 6 illustrates locating the bottom of the blast hole. After the water surface 34a has been recorded the operator releases the cord 28 and repeats the procedure wherein a button is pressed to identify the vessel 22 is at the bottom of the hole 38. if no water is present both a water level button and hole bottom button (both not shown) are pressed at the bottom of the hole 36 and the water depth is recorded as zero.

Figure 7 i!iustrates cutting of the cord. In most cases the cord 26 will be cut at surface and left in the hole 36, However it may be required to remove the vessel 22 and the cord from the hole such as for mud sampling. In this case the cord can be recovered by winding up onto a spool 40 preferably by a too! such as a hig speed battery powered drill ( not shown).

Claims

CLAIMS:

1. A portable and disposable apparatus for rapidly measuring the depth of blast holes and water levels In the same including in combination:

a disposable vessel adapted to be filled with a material to weight the vessel;

the vessel adapted to lowered into a blast hole at the end of a cord;

the vessel having a wide base wherein contact with water in the hole causes immediate deceleratio of the vessel and temporary release of tension in the cord, and wherein contact with the bottom of the hole causes a sustained release of tension in the cord;

cord length measuring and dispensing means to dispense the cord and record/measure the depth at which water in the hole or the bottom of the hole, causes immediate deceleration of the vessel and the temporary and/or sustained release of tension in the cord ;

and wherein,

the dispensed cord is cut post measurement and disposed of with the vessel in the hole and a replacement vessel is attached to end of the freshly cut cord for measuring the next blast hole.

2. The apparatus according to claim 1 wherein, the cord length measuring and dispensing means comprises;

a spool on which the cord is wound and unwound;

the spool adapted to release the cord vertically into a blast hole;

a magnetic brake and measurement pulley assembly in contact with the cord to determine the length of the cord unwound from the spool wherein deceieration of the vessel and release of tension in the cord is detected as a measurement of depth ,

Ί ?

3. The apparatus according to claim 1 wherein the vessel is a disposable plastic vessel adapted to be filled with drill cuttings comprising rocks to weight the vessel,

4. The apparatus according to claim 1 wherein the vessel has a substantially frusta- conical shape with a fiat base wherem contact with water in the hole causes immediate deceleration of the vessel.

5. The apparatus according to claim 1 wherein the vessel has a concave or a cup- shaped base wherein on contact with water in the hole, the configuration of the base causes immediate deceleration of the vessel.

8, Th apparatus according to claim 1 wherein the vessel includes a disposable mud sampling spear to sample and measure the depth of mud in the bottom of the hole wherein the cord is retracted to record the mud sample and depth measurements before cutting and disposing of the cord and vessel in the hole.

7. The apparatus according to claim 1 wherein the cord is disposable cord such as fishing line but may be of another suitable disposable material.

8. The apparatus according to claim 1 wherein there is a global positioning system (GPS) associated with the apparatus to identify the location of the blast hole.

9. The apparatus according to claim 1 wherein there is computer recording means to record the GPS position and depth of the water leve! and depth of th blast hole measured by the apparatus.

10. The apparatus according to claim 9 wherein depth information from the cord length measuring and dispensing means and GPS information is data logged on the computer recording means via keyboard or may be semi-automated by pressing a button on a programmable logic controller (PLC) device.

11. A method of measuring the depth of biast holes and water levels using the apparatus hereinabove described including the steps of:

(a) lowering a weighted vessel attached to a cord from the cord length measuring and dispensing means into a blast hole;

(c) recording via computer recording means the depth at which the vessel comes into contact with any water or when the vessel bottoms at the base of the hole, together with the GPS location of the blast hole:

(e) cutting and disposing of the dispensed cord and the vessel in the hole, and