CN106794436A - For the single resistance heating of high pressure-temperature unit - Google Patents

Abstract

The superhard material being used for as in road milling, sap and this kind of field of ditching is created usually using high pressure-temperature forcing press, so that the sturdy material such as pitch, concrete and stone ruptures.Many such forcing presses include multiple piston components, and these piston components can be acted on unanimously gives unit pressurization.Such unit can include the body and the heating element of at least one uniqueness adjacent with each tank in these tanks with the multiple tanks being arranged therein.Heat can be produced in such forcing press by the circuit for forming the multiple anvils with unique heating element and around the unit.

Description

Separate resistance heating for high pressure high temperature unit

Cross References to Related Applications

This patent claims priority to U.S. Provisional Patent Application No. 62/044,094, filed August 29, 2014, entitled "Symmetric Cell Design"; priority to U.S. Provisional Patent Application No. 62/045,752, filed September 18, 2014, and U.S. Provisional Patent Application No. 62/052,191, entitled "Center Conductor Including Notches for HPHT Units" rights; these Provisional Patent Applications are hereby incorporated by reference in their entirety.

This patent is also a continuation-in-part of US Patent Application Serial No. 14/837,761, filed August 27, 2015, entitled "Balance Unit for High-Pressure, High-Temperature Presses."

Background technique

In fields such as road milling, tunneling and trenching, superhard materials such as polycrystalline diamond can be used to fracture tough materials such as asphalt, concrete and stone. Such superhard materials are typically created using a high-pressure, high-temperature ("HPHT") press. While HPHT presses have been made in various styles over the years, many HPHT presses include multiple piston assemblies that act in unison to pressurize the unit. An example of such an HPHT press is disclosed in U.S. Patent No. 6,336,802 to Hall, which describes a press having a frame containing a plurality of cross bores that serve as Means for attaching multiple cartridges. Each barrel may include a piston therein from which an anvil projects into the cavity created by the intersection of these bores. A plurality of anvils advancing toward the center of the cavity may surround and define a high pressure chamber within the press.

The cells may be arranged within such a high pressure chamber containing the raw material components required to form the superhard material. One example of a feedstock constituent capable of forming a superhard material includes diamond grains disposed within a metal can adjacent to a carbide substrate. The carbide substrate may contain a catalyst that is blown into the diamond grains under specific HPHT conditions to help sinter the diamond grains together. One or more of these pots may be surrounded by a pressure transmitting medium, such as pyrophyllite, which may form a pressure seal in the gap between adjacent anvils, as well as an equalizing pressure around the pots. It is also possible to arrange resistive material within cells which can be heated to a desired temperature when an electric current is passed through the cell from one anvil to the other.

One known cell configuration shown in Figure 1 comprises a cube 100, typically made of pyrophyllite. The cube 100 includes a cylindrical hole 105 therethrough. A plurality of metal tanks 110 may be stacked face to face, may be secured within a salt form 108 disposed within cylindrical bore 105 . A metal tube 109 may surround the salt form 108 and provide an electrical path from one end to the other. At least one resistive heater 107 may be located at either end of the salt mold 108 and provide heat when an electrical current is passed therethrough.

While the cell configuration shown in FIG. 1 may be end-to-end symmetric, this cell configuration lacks the symmetry of the other eight possible planes of symmetry 202 shown in FIG. 2 . This asymmetry can lead to uneven pressure and/or heat distribution. Specifically, each can of the plurality of cans may experience different pressure gradients and temperature gradients across its interior based on its unique position relative to the anvil and resistive heater. Therefore, there exists a need for a more balanced cell design than previously existed.

Contents of the invention

A unit for a HPHT press may comprise a body in which a plurality of tanks are arranged. At least one distinct heater element, eg, a resistive heater, may be disposed adjacent each of the tanks.

At least one temperature sensor may also be arranged within the body to measure the temperature. In various embodiments, each of the tanks or each of the unique heater elements may have at least one temperature sensor.

The at least one heater element may form part of an electrical circuit to the outside of the body. Such circuits may have various configurations. In one example configuration, electrical current may pass from the first anvil through the entry unit, through the first heater element adjacent the first tank, through the first conductive tube around the diameter of the first tank, through the body The inner core die, through the second conductive tube surrounding the second tank, through the second heater element, to the second anvil.

When the anvils are energized, heat can be generated within the unit. Additionally, the voltage drop across each unique heater element, and thus the heat generated, can be determined from the voltage at these anvils. Once determined, the voltage drop across each unique heater element can be adjusted by adjusting the voltage at these anvils.

When a unit includes multiple heater elements, additional circuits may be created, including at least one different heater element and at least one different anvil. Thus, the difference in resistance between a plurality of unique heater elements can be determined from the voltages at these anvils. In some embodiments, it may be desirable to alternate between various circuits.

Where the central mold includes a portion of a first circuit with unique heater elements on either side of the first circuit, the second circuit may have at least one and at least one of the unique heater elements of the first circuit Different unique heater elements.

Description of drawings

Figure 1 is a perspective view of an embodiment of a HPHT cell configuration known in the prior art.

Figure 2 is a perspective view of an embodiment of a cube showing nine possible planes of symmetry.

Fig. 3 is a partially exploded perspective view of a multi-part embodiment of a HPHT unit configuration comprising a generally cuboid-shaped body formed from two mating formworks.

FIG. 4 is an exploded perspective view of a multi-part embodiment of a HPHT unit configuration comprising a generally cuboid-shaped body formed from six generally pyramid-shaped formwork.

5 is a perspective view of an embodiment of portions of a HPHT unit configuration comprising a generally cuboid-shaped body formed from eight generally cuboid-shaped formworks.

Figure 6 is a cross-sectional view of an embodiment of a HPHT cell configuration including a tank disposed within holes on each face thereof.

Figures 7a and 7b are cross-sectional representations of embodiments of current flow through a HPHT cell configuration.

Figure 8a is a perspective view of an embodiment of a generally pyramid-shaped form including a base comprising a different material than the remainder of the form.

Figures 8b and 8c are schematic representations of examples of synthetic pyrophyllite pressing operations.

9 is a perspective view of an embodiment of a dovetail holding together the edges of a generally pyramid-shaped formwork.

Figures 10a and 10b are perspective views of embodiments of HPHT cell configurations shaped as tetrahedrons and dodecahedrons, respectively.

detailed description

Figure 3 shows an embodiment of parts of a unit for an HPHT press comprising a generally cuboid-shaped body 300 formed from two mating formworks 320a,b. The two mating formworks 320a, b may be made of natural or synthetic pyrophyllite or other pressure transmitting material and assembled like clamshells disposed on the central formwork 330 within the body 300 . The central mold 330 may be made of salt or other pressure transmitting material. To hold the body together, the two mating formworks 320a, b may be press fit onto the central formwork 330 or include pins 324 fitable in mating slots 326 .

The generally cuboid-shaped body 300 includes six faces 321a, b, c (only three of these faces are visible), each of which includes a hole 323a, b, c. Each of these holes 323a, b, c may include a respective central axis 329a, b, c passing through the center of the body, and each hole may be sized to receive a separate canister (not shown). Similarly, the central mold 330 may include six seats 333a, b, c, each seat aligned with one of the holes 323a, b, c and may be sized to receive a tank.

Figure 4 shows another embodiment of parts of a unit of a HPHT press comprising a generally cuboid shaped body 400 consisting of six generally pyramid shaped formwork 420a, b, c, d , e, f are formed. The body 400 includes six faces 421b, d, f (only three of these faces are visible), each of which includes a hole 423a, b, c, d, e, f. Each of these holes 423a, b, c, d, e, f may include a respective central axis 429a, b, c, d, e, f passing through the center of the body, and each hole may be sized as Receives a separate tank (not shown). These generally pyramid-shaped formworks 420 a , b , c , d , e , f may each include truncated tips so that they may fit around a central form 430 disposed within the body 400 . Some of these generally pyramid-shaped forms (eg, 420c and e) may include edges 425c, e which, when assembled, may overlap the edges of adjacent forms.

Figure 5 shows yet another embodiment of parts of a unit of an HPHT press comprising eight generally cubically shaped formworks 520a, b, c, d, e, f, g and h The body 500 is generally cuboid in shape, each formwork having truncated corners containing surfaces perpendicular to an axis passing through the center of the body 500 . Apertures 523a, b, c, d, e, f, g, and h are disposed within each respective cube-shaped formwork 520a, b, c, d, e, f, g, and h. Each of apertures 523a, b, c, d, e, f, g, and h may be sized to receive a separate canister (not shown) comprising a through center of body 500 and through The axes of the corresponding corners of the body 500 .

Regardless of the chosen configuration, there are many advantages to using such a balanced unit in an HPHT press. For example, Figure 6 shows an embodiment of a unit that includes canisters 640 disposed within holes on each face of the unit. Each of these canisters 640 may be formed from a metal such as niobium and have superhard grains 642 , such as diamond grains, disposed adjacent a substrate in the canister, such as a tungsten carbide substrate 644 . A separate metal tube 609 may surround each of these cans 640 and may provide an electrical path from one end to the other. Further, each of the cans 640 can have at least one resistive heater 607 located at either end of the cans, which can provide heat when a current is passed through the resistive heater. In the illustrated embodiment, the central die 630 disposed within the unit may also be resistive and may act as a unified heater for the unit.

In such a configuration, as the anvils of the HPHT press come together and apply pressure to all sides of the cell, each of the cans can receive substantially equal amounts of pressure and from as many opposing directions. It is believed that this substantially equal amount of pressure may result in a more uniform final product. Further, since the current is passed from one anvil to the other, the current can travel through the first resistive heater, the first metal tube, the central die, and then exit the second metal tube and the second resistive heater. Through this electrical path, each of the cans can receive substantially the same amount of heat and from as many opposite directions. It is believed that this substantially equal amount of heat may further result in a more uniform final product. To more accurately ensure substantially equal amounts of heat, at least one temperature sensor 632, such as a thermocouple or a thermistor, may be arranged within the body to measure the temperature. In various embodiments, each of the tanks 640 or each of the resistive heaters 607 may have at least one temperature sensor.

Figures 7a and 7b show embodiments of currents 750a,b passing through cells having different natural resistances within resistive heaters located at either end of the tanks arranged in the cells. These natural differences in resistance can result in differences in the voltage drop across such resistive heaters, and thus in the amount of heat dissipated. By alternately charging the anvils, it was possible to determine which pair of resistive heaters naturally dissipated more heat into its adjacent tank. With this knowledge, it is possible to equalize or more accurately control the temperature experienced by each pot by adjusting the voltage of each anvil to increase or decrease the heat dissipated by each resistive heater.

For example, Fig. 7a shows from a first anvil (not shown) having a voltage of 10v through a first resistive heater 751a, a first metal tube 752a, a center die 753a, a second metal tube 754a, and a second resistive heating The current 750a is delivered by the device 755a to a second anvil (not shown) having a voltage of 2v. This means that 8 volts have been dissipated in the system as heat due to the resistance in the circuit. Fig. 7b shows from a first anvil (not shown) having a voltage of 10v through a first resistive heater 751b, a first metal tube 752b, a center die 753b, a third metal tube 756b, and a third resistive heater 757a Current 750b delivered to a third anvil (not shown) having a voltage of 3v. Thus, 7 volts are dissipated in the system as heat when current is passed through the different pairs of resistive heaters. With this knowledge, it may be desirable to increase or decrease the voltage at the second or third anvil to equalize or more accurately control the heat received by each can. As previously discussed, it is believed that substantially equal amounts of heat supplied to each tank may result in a more uniform final product.

One of these advantages of forming a balancing unit partly from a generally pyramid-shaped formwork as described above is the ease of creating a body comprising multiple materials with different properties. For example, Figure 8a shows an embodiment of a formwork 820a that is generally pyramid-shaped, including a base 826a comprising a different material than the remainder of the formwork 828a. This type of configuration may be desirable when a portion of a cell (the edge of the cell) is expected to be extruded between adjacent anvils when pressurized in an HPHT press. It may be desirable that such extrusion forms a spacer between adjacent anvils, allowing a sufficiently high pressure to be maintained. Due to the importance of such gaskets, the properties of the material from which they are formed can be critical. The rest of the unit (the part that does not form the gasket) may require significantly different material properties. Specifically, this remainder may need to flow more easily in order to balance the forces within the cell. Accordingly, it may be desirable that the gasket material or base 826a of the embodiment shown in Figure 8a be less flowable under HPHT conditions than the remaining material or portion 828a.

When working with solid cubes, pressing synthetic pyrophyllite may be useful for creating multiple materials including Simple operation of the pyramid-shaped formwork. For example, Figures 8b and 8c illustrate an embodiment of a synthetic pyrophyllite pressing operation in which the remainder of the material 828b is first pressed into a mold 860b, after which base material 826c comprising different material properties is pressed into the same mold 860b. A cubic unit comprising different material properties from the outside to the inside can then be created by fitting together a plurality of pyramid-shaped formworks as described previously.

As shown in the embodiment shown in Figure 9, another advantage of forming the counterbalancing unit partly by generally pyramid-shaped formwork 920a, b is that by combining the edges of adjacent pyramid-shaped formwork 920a, b with multiple The ability of the two dovetails 927 to bond together at least to hold portions of the unit together.

Although we have generally discussed up to this point (at which point each of the faces of the cell are generally planar and arranged at substantially the same angle to adjacent faces) the substantially cuboid-shaped cells, but those skilled in the art will recognize that other shapes, such as tetrahedrons and dodecahedrons, can be used with the present invention. The respective embodiments are shown in Figures 10a and 10b accordingly.

Although the invention has been described specifically with respect to the drawings herein, it should be understood that other and further modifications other than those shown or suggested herein may be made within the scope and spirit of the invention.

Claims (20)

1. A unit for a high-pressure high-temperature press, the unit comprising: a body having a plurality of tanks disposed therein; and At least one unique heater element is adjacent to each of the canisters. 2. The unit of claim 1, wherein the heater element comprises a resistive heater. 3. The unit of claim 1, further comprising at least one temperature sensor within the body. 4. The unit of claim 3, wherein the at least one temperature sensor comprises at least one temperature sensor for each of the tanks. 5. The unit of claim 3, wherein the at least one temperature sensor comprises at least one temperature sensor for each of the unique heater elements. 6. The unit of claim 1, further comprising a conductive tube surrounding the diameter of each of the tanks. 7. A unit as claimed in claim 1, wherein at least one of the heater elements forms part of an electrical circuit to the outside of the body. 8. A unit as claimed in claim 7, wherein the circuit comprises at least two anvils of a HPHT press. 9. The unit of claim 7, wherein the electrical circuit includes at least two heater elements and a central mold within the body. 10. A method for generating heat in a high-pressure, high-temperature press, the method comprising: providing a plurality of tanks arranged within the unit and at least one unique heater element adjacent to each of the tanks; A first electrical circuit is formed comprising at least one of the unique heater elements and at least two anvils surrounding the unit. 11. The method of claim 10, further comprising determining the voltage drop across the at least one unique heater element from the voltages at the anvils. 12. The method of claim 10, further comprising determining the heat generated by the at least one unique heater element from the voltages at the anvils. 13. The method of claim 10, further comprising adjusting the voltage drop across the at least one unique heater element by adjusting the voltage at the anvils. 14. The method of claim 10, further comprising forming a second circuit comprising at least a different unique heater element and at least one different anvil. 15. The method of claim 14, further comprising determining the difference in resistance between the unique heater element and the different unique heater element from the voltages at the anvils. 16. The method of claim 14, further comprising alternating between the first circuit and the second circuit. 17. The method of claim 10, wherein the first circuit includes at least two of the unique heater elements. 18. The method of claim 17, wherein the circuit further comprises a central die within the unit. 19. The method of claim 17, further comprising forming a second circuit comprising at least one of the unique heater elements and at least one different unique heater element of the first circuit. 20. The method of claim 19, wherein the first circuit and the second circuit each comprise a central mold within the cell.