Thick pointed superhard material
09540886 ยท 2017-01-10
Assignee
Inventors
- David R. Hall (Provo, UT, US)
- Ronald B. Crockett (Payson, UT, US)
- Jeff Jepson (Spanish Fork, UT, US)
- Scott Dahlgren (Alpine, UT, US)
- John Bailey (Spanish Fork, UT, US)
Cpc classification
E21B10/5673
FIXED CONSTRUCTIONS
E21B10/5676
FIXED CONSTRUCTIONS
International classification
E21B10/567
FIXED CONSTRUCTIONS
Abstract
In one aspect of the invention, a high impact resistant tool includes a superhard material bonded to a cemented metal carbide substrate at a non-planar interface. The superhard material has a substantially pointed geometry with a sharp apex having a radius of curvature of 0.050 to 0.125 inches. The superhard material also has a thickness of 0.100 to 0.500 inches thickness from the apex to a central region of the cemented metal carbide substrate.
Claims
1. A high impact resistant tool, comprising a cutting end extending a height from a grip region and a sintered polycrystalline diamond material bonded to a cemented metal carbide substrate at an interface, said diamond material at least partially forming the cutting end, the cutting end comprising: a side surface extending from an outer diameter of the grip region to an apex having a central axis, said central axis passing through said cemented metal carbide substrate, said apex having a radius of curvature from about 0.050 to about 0.160 inches measured in a vertical orientation from said central axis, the diamond material forming the side surface and the apex, and the thickness of the diamond material along the central axis from the interface to the apex being greater than the radius of curvature.
2. The tool of claim 1, wherein at least a portion of the side surface forms about a 35 to 55 degree angle with the central axis.
3. The tool of claim 2, wherein the angle is substantially 45 degrees.
4. The tool of claim 1, wherein the a convex side or a concave side.
5. The tool of claim 1, wherein the interface comprises a tapered surface extending from a cylindrical rim of the substrate and intersecting a flatted axial region formed in the substrate.
6. The tool of claim 5, wherein the flatted axial region comprises a diameter of about 0.125 to about 0.250 inches.
7. The tool of claim 5, wherein the tapered surface is a convex side or a concave side.
8. The tool of claim 5, wherein the tapered surface incorporates nodules, grooves, dimples, protrusions, reverse dimples, or combinations thereof.
9. The tool of claim 1, wherein the radius is about 0.090 to about 0.110 inches.
10. The tool of claim 1, wherein the thickness is about 0.100 to about 0.500 inches.
11. The tool of claim 10, wherein the thickness from the apex to the interface is about 0.125 to about 0.275 inches.
12. The tool of claim 1, wherein the diamond material and the substrate comprise a total thickness of about 0.200 to about 0.700 inches from the apex to a base of the substrate.
13. The tool of claim 1, wherein the sintered polycrystalline diamond material comprises synthetic diamond, silicon bonded diamond, cobalt bonded diamond, thermally stable diamond, polycrystalline diamond with a binder concentration of 1 to 40 weight percent, infiltrated diamond, layered diamond, monolithic diamond, polished diamond, course diamond, fine diamond, metal catalyzed diamond, or combinations thereof.
14. The tool of claim 1, wherein a volume of the diamond material is 75 to 150 percent of a volume of the substrate.
15. The tool of claim 1, wherein the diamond material has a polished surface finish.
16. The tool of claim 1, wherein the tool is incorporated in drill bits, percussion drill bits, roller cone bits, shear bits, milling machines, indenters, mining picks, asphalt picks, cone crushers, vertical impact mills, hammer mills, jaw crushers, asphalt bits, chisels, trenching machines, or combinations thereof.
17. The tool of claim 1, wherein the substrate is bonded to an end of a carbide segment.
18. The tool of claim 17, wherein the carbide segment is brazed or press fit to a steel body.
19. The tool of claim 1, wherein the diamond material is a polycrystalline structure with an average grain size of 1 to 100 microns.
20. The tool of claim 1, wherein the diamond material comprises a 1 to 5 percent concentration of binding agents by weight.
21. A high impact resistant tool, comprising: a sintered polycrystalline diamond material bonded to a cemented metal carbide substrate at an interface, said diamond material having a convex side surface extending in a general direction from an outer diameter of the diamond material and terminating in a rounded apex having a central axis therethrough, the apex being rounded in an axial direction, wherein the convex side surface has a convex cross sectional profile when viewed along a plane axially intersecting the central axis and forms a first angle from an axis parallel to the central axis in a lower portion of the sintered polycrystalline diamond material, a second angle from the axis in a middle portion of the sintered polycrystalline diamond material, and a third angle from the axis in an upper portion of the sintered polycrystalline diamond material; and wherein the convex side surface has a radius of curvature that is greater than a radius of curvature of the rounded apex.
22. The high impact resistant tool of claim 21, wherein the first angle ranges from 25 to 33 degrees, the second angle ranges from 33 to 40 degrees, and the third angle ranges from 40 to 50 degrees.
23. The high impact resistant tool of claim 21, wherein the first angle ranges from 25 to 33 degrees.
24. The high impact resistant tool of claim 21, wherein the second angle ranges from 33 to 40 degrees.
25. The high impact resistant tool of claim 21, wherein the third angle ranges from 40 to 50 degrees.
26. The high impact resistant tool of claim 21, wherein the rounded apex has a radius of curvature from about 0.050 to about 0.160 inches measured in a vertical orientation from the central axis.
27. The high impact resistant tool of claim 21, wherein the diamond material comprises a thickness measured from the apex to the interface from about 0.100 to about 0.500 inches.
28. The high impact resistant tool of claim 21, wherein the thickness from the apex to the interface is about 0.125 to about 0.275 inches.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF THE INVENTION
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(33) The shank 101a may be adapted to be attached to a driving mechanism. A protective spring sleeve 105a may be disposed around the shank 101a both for protection and to allow the high impact resistant tool 100 to be press fit into a holder while still being able to rotate. A washer 106a may also be disposed around the shank 101a such that when the high impact resistant tool 100a is inserted into a holder the washer 106a protects an upper surface of the holder and also facilitates rotation of the tool 100. The washer 106a and sleeve 105a may be advantageous since they may protect the holder which may be costly to replace.
(34) The high impact resistant tool 100a also comprises a tip 107a bonded to an end 108a of the frustoconical second segment 104a of the body 102a. The tip 107a comprises a superhard material 109a bonded to a cemented metal carbide substrate 110a at a non-planar interface, as discussed below. The tip 107a may be bonded to the cemented metal carbide substrate 110a through a high pressure-high temperature process.
(35) The superhard material 109a may be a polycrystalline structure with an average grain size of 10 to 100 microns. The superhard material 109a may comprise diamond, polycrystalline diamond, natural diamond, synthetic diamond, vapor deposited diamond, silicon bonded diamond, cobalt bonded diamond, thermally stable diamond, polycrystalline diamond with a binder concentration of 1 to 40 percent by weight, infiltrated diamond, layered diamond, monolithic diamond, polished diamond, course diamond, fine diamond, cubic boron nitride, diamond impregnated matrix, diamond impregnated carbide, non-metal catalyzed diamond, or combinations thereof.
(36) The superhard material 109a may also comprise a 1 to 5 percent concentration of tantalum by weight as a binding agent. Other binding agents that may be used with the present invention include iron, cobalt, nickel, silicon, hydroxide, hydride, hydrate, phosphorus-oxide, phosphoric acid, carbonate, lanthanide, actinide, phosphate hydrate, hydrogen phosphate, phosphorus carbonate, alkali metals, ruthenium, rhodium, niobium, palladium, chromium, molybdenum, manganese, tantalum or combinations thereof. In some embodiments, the binding agent is added directly to a mixture that forms the superhard material 109a mixture before the HPHT processing and do not rely on the binding agent migrating from the cemented metal carbide substrate 110 into the mixture during the HPHT processing.
(37) The cemented metal carbide substrate 110a may comprise a concentration of cobalt of 1 to 40 percent by weight and, more preferably, 5 to 10 percent by weight. During HPHT processing, some of the cobalt may infiltrate into the superhard material 109a such that the cemented metal carbide substrate 110a comprises a slightly lower cobalt concentration than before the HPHT process. The superhard material 109a may preferably comprise a 1 to 5 percent cobalt concentration by weight after the cobalt or other binding agent infiltrates the superhard material 109a during HPHT processing.
(38) Now referring to
(39) The superhard material 109b comprises a substantially pointed geometry 210a with a sharp apex 202a comprising a radius of curvature of 0.050 to 0.125 inches. In some embodiments, the radius of curvature is 0.090 to 0.110 inches. It is believed that the apex 202a is adapted to distribute impact forces across the central region 201a, which may help prevent the superhard material 109b from chipping or breaking.
(40) The superhard material 109b may comprise a thickness 203 of 0.100 to 0.500 inches from the apex 202a to the central region 201a and, more preferably, from 0.125 to 0.275 inches. The superhard material 109b and the cemented metal carbide substrate 110b may comprise a total thickness 204 of 0.200 to 0.700 inches from the apex 202 to a base 205 of the cemented metal carbide substrate 110b. The apex 202a may allow the high impact resistant tool 100 illustrated in
(41) The pointed geometry 210a of the superhard material 109b may comprise a side 214 which forms an angle 150 of 35 to 55 degrees with a central axis 215 of the tip 107b, though the angle 150 may preferably be substantially 45 degrees. The included angle 152 may be a 90 degree angle, although in some embodiments, the included angle 152 is 85 to 95 degrees.
(42) The pointed geometry 210a may also comprise a convex side or a concave side. The tapered surface 200 of the cemented metal carbide substrate 110b may incorporate nodules 207 at a non-planar interface 209a between the superhard material 109b and the cemented metal carbide substrate 110b, which may provide a greater surface area on the cemented metal carbide substrate 110b, thereby providing a stronger interface. The tapered surface 200 may also incorporate grooves, dimples, protrusions, reverse dimples, or combinations thereof. The tapered surface 200 may be convex, as in the current embodiment of the tip 107b, although the tapered surface may be concave in other embodiments.
(43) Advantages of having a pointed apex 202a of superhard material 109 as illustrated in
(44) The performance of the geometries 210a and 210b were compared a drop test performed at Novatek International, Inc. located in Provo, Utah. Using an Instron Dynatup 9250G drop test machine, the tips 107b and 107c were secured to a base of the machine and weights comprising tungsten carbide targets were dropped onto the tips 107b and 107c.
(45) It was shown that the geometry 210a of the tip 107b penetrated deeper into the tungsten carbide target, thereby allowing more surface area of the superhard material 109b to absorb the energy from the falling target. The greater surface area of the superhard material 109b better buttressed the portion of the superhard material 109b that penetrated the target, thereby effectively converting bending and shear loading of the superhard material 109b into a more beneficial quasi-hydrostatic type compressive forces. As a result, the load carrying capabilities of the superhard material 109b drastically increased.
(46) On the other hand, the geometry 210b of the tip 107c is blunter and as a result the apex 202b of the superhard material 109c hardly penetrated into the tungsten carbide target. As a result, there was comparatively less surface area of the superhard material 109c over which to spread the energy, providing little support to buttress the superhard material 109c. Consequently, this caused the superhard material 109c to fail in shear/bending at a much lower load despite the fact that the superhard material 109c comprised a larger surface area than that of superhard material 109b and used the same grade of diamond and carbide as the superhard material 109b.
(47) In the event, the pointed geometry 210a having an apex 202a of the superhard material 109b surprisingly required about 5 times more energy (measured in joules) to break than the blunter geometry 210b having an apex 202b of the superhard material 109c of
(48) Surprisingly, in the embodiment of
(49) In addition, a third embodiment of a tip 107c illustrated in
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(51) As can be seen, embodiments of tips that include a superhard material having the feature of being thicker than 0.100 inches, such as tip 107c, or having the feature of a radius of curvature of 0.075 to 0.125 inch, such as tip 107d, is not enough to achieve the impact resistance of the tip 107b. Rather, it is unexpectedly synergistic to combine these two features.
(52) The performance of the present invention is not presently found in commercially available products or in the prior art. In the prior art, it was believed that an apex of a superhard material, such as diamond, having a sharp radius of curvature of 0.075 to 0.125 inches would break because the radius of curvature was too sharp. To avoid this, rounded and semispherical geometries are commercially used today. These inserts were drop-tested and withstood impacts having energies between 5 and 20 joules, results that were acceptable in most commercial applications, albeit unsuitable for drilling very hard rock formations.
(53) After the surprising results of the above test, a Finite Element Analysis (FEA) was conducted upon the tips 107b and 107c, the results of which are shown in
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(55) As discussed, the tips 107b and 107c broke when subjected to the same stress during the test. Nonetheless, the difference in the geometries 210a and 210b of the superhard material 109b and 109c, respectively, caused a significant difference in the load required to reach the Von Mises stress level at which each of the tips 107b and 107c broke. This is because the geometry 210a with the pointed apex 202a distributed the loads more efficiently across the superhard material 109b than the blunter apex 202b distributed the load across the superhard material 109c.
(56) In
(57) In the FEA 107c, it can be seen that both the higher and lower stresses are concentrated in the superhard material 109c, as the FEA 109c indicates. These combined stresses, it is believed, causes transverse rupture to actually occur in the superhard material 109c, which is generally more brittle than the softer carbide substrate.
(58) In the FEA 107b, however, the FEA 109b indicates that the majority of high stress remains within the superhard material 109b while the lower stresses are actually within the carbide substrate 110b that is more capable of handling the transverse rupture, as indicated in FEA 110b. Thus, it is believed that the thickness of the superhard material is critical to the ability of the superhard material to withstand greater impact forces; if the superhard material is too thick it increases the likelihood that transverse rupture of the superhard material will occur, but if the superhard material is too thin it decreases the ability of the superhard material to support itself and withstand higher impact forces.
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(67) Now referring to
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(73) The high impact resistant tool may be an insert in a drill bit, as in the embodiments of
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(79) Milling machines may also incorporate the present invention. The milling machines may be used to reduce the size of material such as rocks, grain, trash, natural resources, chalk, wood, tires, metal, cars, tables, couches, coal, minerals, chemicals, or other natural resources.
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(86) Other applications not shown, but that may also incorporate the present invention, include rolling mills; cleats; studded tires; ice climbing equipment; mulchers; jackbits; farming and snow plows; teeth in track hoes, back hoes, excavators, shovels; tracks, armor piercing ammunition; missiles; torpedoes; swinging picks; axes; jack hammers; cement drill bits; milling bits; drag bits; reamers; nose cones; and rockets.
(87) Whereas the present invention has been described in particular relation to the drawings attached hereto, it should be understood that other and further modifications apart from those shown or suggested herein, may be made within the scope and spirit of the present invention.