Device and method for collecting borehole samples
A device and method for collecting borehole samples includes a receptacle having an inlet adapted to engage with a casing positioned in a drill hole, and at least one outlet through which a borehole sample exits from the receptacle. The receptacle is adapted to fit around a drill rod used in drilling the drill hole with the inlet providing clearance for the drill rod and the receptacle adapted to capture cuttings and cutting fluid entering the receptacle through the inlet during a drilling operation.
The present teachings relate generally to the field of mining and measurements made during the drilling of boreholes in a mining operation.
BACKGROUNDDrilling boreholes used in mining operations is generally performed using rotary drilling techniques. A rotary drill bit is coupled to one end of a drilling tool assembly, and the assembly is rotated while applying axial force to the bit. A drilling fluid is pumped through the interior of the drilling tool assembly and outward through orifices, called nozzles or jets, disposed in the body of the drill bit. The drilling fluid that is discharged through the jets performs a number of functions, including cooling and lubricating the drill bit, applying hydrostatic pressure to the earth formations that have been drilled in order to control pressure of fluids in the pore spaces of the formations, and lifting drill cuttings generated by the drill bit to the earth's surface through an annular space between the drilled borehole and the exterior of the drilling tool assembly.
Before extensive drilling, or blasting, or both, is performed in an area for mining of various minerals or other substances, it would be desirable to have an accurate idea of the composition of materials in the area that is to be mined, the size and direction of a strata or vein of a mineral that is desired to be mined, and characteristics of materials surrounding the area that is to be mined. During drilling operations using conventional longhole drilling equipment, additional drill steel or drill rods can be added as the drill percussion bit and drill rod penetrate into the earth to a depth greater than the length of the first drill rod. During the longhole drilling operation the drilling fluid continues to be pumped down through the one or more drill rods and out through the drill bit so that it can cool the drill bit during the drilling operation and then flush the cuttings back up along the borehole between the drill rod and the borehole. The cuttings taken from various depths are representative of the mineral or other material located at that depth.
SUMMARYA device according to various embodiments is provided for collecting borehole samples in the form of cuttings and cutting fluid flushed up out of a borehole during a drilling operation. The device includes a receptacle having an inlet that is adapted to engage with a casing positioned at least partially in a borehole. At least one outlet is also provided in the receptacle, with the at least one outlet providing a passage through which a borehole sample exits from the receptacle. The receptacle is adapted to fit around a drill rod used in drilling the borehole with the inlet providing clearance for the drill bit and drill rod and the receptacle adapted to capture cuttings and cutting fluid entering the receptacle through the inlet during a drilling operation.
According to various embodiments, the receptacle can be in the form of an open catch basin that is fitted around a casing through which the drill rod passes during a drilling operation such that the catch basin collects all cuttings and cutting fluid that exit from the casing during the drilling operation.
According to various embodiments, the receptacle of the device for collecting borehole samples can be in the form of a closed container having an inlet adapted to engage with a casing in a borehole, an opening aligned with the inlet and through which the drill rod and drill bit can pass during a drilling operation, and at least one outlet from which the collected cuttings and cutting fluid in the receptacle can be removed for analysis.
According to various embodiments, a method of collecting borehole samples can include drilling a borehole into the earth for a first distance using a reaming tool on the end of a drill rod. The reaming tool can be used to form a first, larger diameter portion of the borehole. The remainder of the borehole can then be formed by a drill bit, such as the drill bit of a conventional longhole boring machine wherein a cutting fluid is passed down through the drill rod and drill bit such that cuttings generated during the drilling operation are flushed up out of the borehole around the outside of the drill rod. After drilling into the earth a desired distance using the reaming tool, the reaming tool and drill rod can be removed from the borehole, and a casing can be inserted into the borehole, with an exposed end of the casing extending to or above ground level.
A borehole sample collector can then be attached to the exposed end of the casing or an extension thereof, with the borehole sample collector comprising a receptacle that completely surrounds the exposed end of the casing or extension thereof such that substantially all cuttings and cutting fluid generated during the drilling operation pass from the casing into the receptacle. A drill bit on the end of a drill rod can then be inserted through an opening that passes through the borehole sample collector and into the casing to continue the drilling operation.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are intended to provide a further explanation of the present invention, as claimed.
BRIEF DESCRIPTION OF THE DRAWINGSVarious embodiments of the present teachings are exemplified in the accompanying drawings. The teachings are not limited to the embodiments depicted in the drawings, and include equivalent structures and methods as set forth in the following description and as would be known to those of ordinary skill in the art in view of the present teachings. In the drawings:
During a mining operation it would be desirable to have an accurate picture of the types of minerals or other substances, and the locations and the quantities of the minerals or other substances located in the ground at a potential mining site. It would also be desirable during a mining operation to know the composition of the materials in the ground at a potential mining site so that the placement and quantity of explosives needed during the mining operation could be determined with a high degree of accuracy. Longhole drilling equipment can be used to drill the blast holes that can be used for placement of explosives at a potential mining site.
The longhole drilling machine can be an electric hydraulic machine that drills a hole into the ground by rotating a diamond drill bit on the end of a drill rod and by moving the diamond drill bit and drill rod in an axial direction. A longhole drilling machine can continue to drill the hole to greater depths by the continued addition of drill rods to the end of the drill rod at the opposite end from the drill bit. During the drilling operation a cutting fluid can be forced down through the center of the one or more drill rods and out through the drill bit, with the cutting fluid providing the benefits of cooling and lubricating the drill bit, as well as applying a hydrostatic pressure to the earth formations that have been drilled, and lifting the resulting drill cuttings generated by the bit back to the earth's surface through the annular space defined between the drilled borehole and the exterior of the drilling tool assembly. As the drill bit at the end of one or more drill rods continues to penetrate the earth to greater depths, the cuttings generated at each new depth are representative of the materials located in the earth at that depth.
According to various embodiments, such as shown in
A top portion 33 of the borehole 32 can be drilled or reamed to a larger diameter using a reaming tool (not shown) such that a casing 50 can be fitted into the top portion of the borehole, with the casing 50 having a large enough inner diameter to allow passage of the drill bit 42 and drill rod 40. The casing 50 extending into the borehole at the larger diameter portion 33 can extend to or above the surface of the ground 30, and can be provided with a fitting at its top end such that the borehole sample collector 20 can be joined with the top end of the casing 50.
As shown in
The inlet fitting 26b and aligned fitting 26a, as shown in
During a drilling operation, the borehole sample collector 20 can be joined to the top end of casing 50 by clamping the fitting 52 at the top end of casing 50 to a mating fitting 26b′ on inlet fitting 26b of the sample collector 20. As the drill bit 42 at the end of drill rod 40 penetrates further into the earth, cuttings are flushed by the cutting fluid pumped down through drill rod 40 and out through drill bit 42 back up around the drill rod 40 through the inlet 26b and into the borehole sample collector 20. In the embodiment shown in
One of ordinary skill in the art will recognize that although an embodiment such as shown in
According to various embodiments, such as shown in
In the exemplary embodiment of
Borehole sample collectors such as those discussed above with regard to various embodiments, provide a means for collecting the cuttings and cutting fluid produced at a known depth of a borehole during a drilling operation. By allowing for the capture of all cuttings and cutting fluid produced during a drilling operation at selected depths of the drill hole, the borehole sample collectors according to various embodiments as discussed above, allow for the collection of cuttings at various depths or positions of the drill hole while using conventional longhole drilling machinery, and provide a convenient means for collecting only cuttings and cutting fluid at particular desired locations to provide an accurate map of the composition of materials in the mine site. The amount of various minerals or other materials found at various depths and locations in the mine site, as obtained by drilling holes and collecting cutting samples using a borehole sample collector according to various embodiments, yields information valuable in deciding where to mine for a particular mineral, and where to place explosives if blasting will be used to mine desired minerals.
Other embodiments of the present invention will be apparent to those skilled in the art from consideration of the present specification and practice of the present invention disclosed herein. It is intended that the present specification and examples be considered as exemplary only with a true scope and spirit of the invention being indicated by the following claims and equivalents thereof.
Claims
1. A device for collecting borehole samples, comprising:
- a receptacle including an inlet adapted to engage with a casing positioned in a borehole, and at least one outlet through which a borehole sample exits from the receptacle; and
- the receptacle adapted to fit around a drill rod used in drilling the borehole with the inlet providing clearance for the drill rod and the receptacle adapted to capture cuttings and cutting fluid entering the receptacle through the inlet during a drilling operation.
2. The device of claim 1, wherein the inlet of the receptacle is a section of pipe adapted to engage with the casing in a borehole, the section of pipe being attached to a housing of the receptacle and extending into the housing with the housing surrounding the section of pipe to capture the cuttings and cutting fluid coming from the casing during a drilling operation.
3. The device of claim 1, wherein the receptacle is defined by an outer housing, the inlet extending into the outer housing on one side of the outer housing and a drill rod clearance opening provided on the opposite side of the outer housing aligned with the inlet.
4. The device of claim 3, wherein the at least one outlet is formed through the outer housing at a level lower than a level where a borehole sample enters the outer housing from the inlet so the sample will flow out of the at least one outlet.
5. The device of claim 1, wherein the receptacle is formed with the inlet aligned with an opening through the opposite side of the receptacle, the inlet and the aligned opening adapted to receive a drill rod therethrough, and the at least one outlet providing fluid communication from a collection volume of the receptacle surrounding the drill rod to outside the receptacle.
6. The device of claim 1, wherein:
- the receptacle is formed with an outer periphery of the receptacle defined by a larger diameter pipe section;
- a first disk joined across one end of the larger diameter pipe section forming a top of the receptacle and a second disk joined across the opposite end of the larger diameter pipe section forming a bottom of the receptacle;
- a first smaller diameter pipe section joined to and penetrating through the top of the receptacle;
- a second, smaller diameter pipe section joined to and penetrating through the bottom of the receptacle, the second, smaller diameter pipe section being substantially aligned with the first smaller diameter pipe section; and
- the at least one outlet being formed by one or more smaller diameter pipe sections joined to the larger diameter pipe section.
7. The device of claim 6, wherein two of the at least one outlet are joined to the larger diameter pipe section on approximately diametrically opposed sides of the larger diameter pipe section and are axially offset relative to each other in the direction of an axis through the substantially aligned first and second smaller diameter pipe sections.
8. The device of claim 7, wherein:
- the first and second disks forming the top and bottom of the receptacle are substantially parallel to each other and form an acute angle with the axis through the substantially aligned first and second smaller diameter pipe sections.
9. The device of claim 1, wherein:
- the receptacle comprises an inner portion including the inlet and a passageway for a drill rod used in drilling a borehole; and
- an outer portion surrounding the inner portion and forming a catch basin in which cuttings and cutting fluid entering the receptacle from the inlet during a drilling operation are collected before exiting the receptacle through the at least one outlet.
10. The device of claim 9, wherein the inner portion is at least partially defined by a smaller diameter pipe section and the outer portion is at least partially defined by a larger diameter pipe section concentrically disposed around the smaller diameter pipe section.
11. The device of claim 10, where the outer portion is further defined by an annular plate joined between the smaller diameter pipe section and the larger diameter pipe section.
12. The device of claim 11, wherein the annular plate is joined to the smaller diameter pipe section and the larger diameter pipe section at an acute angle relative to the centerlines of the smaller diameter pipe section and larger diameter pipe section such that the cuttings and cutting fluid entering the receptacle from the inlet during a drilling operation will flow as a result of gravity toward a lower one of the at least one outlet which is provided through the larger diameter pipe section near the intersection of the annular plate and the larger diameter pipe section.
13. A method of collecting borehole samples, comprising:
- drilling a borehole into the earth for a first distance using a drilling or reaming tool bit on the end of a drill rod wherein a cutting fluid is passed down through the drill rod and bit such that cuttings generated during the drilling operation are flushed up out of the borehole around the outside of the drill rod;
- removing the drill rod and bit from the borehole;
- inserting a casing into the borehole with an exposed end of the casing extending to or above ground level;
- attaching a borehole sample collector to the exposed end of the casing or an extension thereof;
- the borehole sample collector comprising a receptacle that completely surrounds the exposed end of the casing or extension thereof such that substantially all cuttings and cutting fluid generated during the drilling operation pass from the casing into the receptacle; and
- reinserting a drill rod and bit through an opening through the borehole sample collector and into the casing to continue drilling.
14. The method of claim 13, wherein:
- a borehole sample from a desired depth is collected by emptying the borehole sample collector of substantially all contents when the drill bit is approximately at the desired depth;
- continuing the drilling operation at the desired depth and collecting the resulting cuttings in the borehole sample collector.
15. The method of claim 13, wherein the borehole is drilled into the earth at an angle relative to the ground surface of approximately 90°.
16. The method of claim 13, wherein the borehole is drilled into the earth at an angle relative to the ground surface that is different than 90°.
17. The method of claim 13, wherein the drilling comprises rotating the drill rod and drill bit and moving the drill rod and drill bit in an axial direction.
18. The method of claim 13, wherein the drilling operation is performed by a longhole drilling apparatus.
19. The method of claim 13, wherein additional drill rods are connected to the drill rod to drill to a desired length of borehole, and a borehole sample is taken at the bottom of the borehole by collecting the cuttings and cutting fluid that enter the borehole sample collector during the drilling operation at the bottom of the borehole.
20. The method of claim 13, wherein the cuttings collected in the borehole sample collector are analyzed to determine at least one of type, location, or quantity of materials that exist in the ground at a potential mining site.
Type: Application
Filed: Jul 30, 2004
Publication Date: Feb 2, 2006
Inventor: David Moran (Lac du Bonnet)
Application Number: 10/903,184
International Classification: E21B 49/00 (20060101);