Wear-resistant, polycrystalline diamond compacts (“PDCs”) are utilized in a variety of mechanical applications. For example, PDCs are used in drilling tools (e.g., cutting elements, gage trimmers, etc.), machining equipment, bearing apparatuses, wire-drawing machinery, and in other mechanical apparatuses.
PDCs have found particular utility as superabrasive cutting elements in rotary drill bits, such as roller cone drill bits and fixed cutter drill bits. A PDC cutting element typically includes a superabrasive polycrystalline diamond layer commonly known as a polycrystalline diamond table. The polycrystalline diamond table is formed and bonded to a substrate using a high-pressure/high-temperature (“HPHT”) process. The PDC cutting element may be brazed directly into a preformed pocket, socket, or other receptacle formed in a bit body. The substrate may often be brazed or otherwise joined to an attachment member, such as a cylindrical backing A rotary drill bit typically includes a number of PDC cutting elements affixed to the bit body. It is also known that a stud carrying the PDC may be used as a PDC cutting element when mounted to a bit body of a rotary drill bit by press-fitting, brazing, or otherwise securing the stud into a receptacle formed in the bit body.
Conventional PDCs are normally fabricated by placing a layer of diamond particles adjacent to a surface of a cemented-carbide substrate and into a can assembly. The can assembly including the cemented-carbide substrate and layer of diamond particles therein may be surrounded by various different pressure transmitting media (e.g., salt liners), positioned in a graphite tube having graphite end caps disposed at respective ends of the graphite tube that forms a heater assembly, and finally embedded in a cube-shaped gasket medium (e.g., pyrophyllite). In an HPHT process used to form a PDC, anvils of an ultra-high pressure cubic press apply pressure to the cube-shaped gasket medium and the contents therein, while the cemented-carbide substrate and layer of diamond particles are controllably heated to a selected temperature at which sintering of the diamond particles is effected by passing a current through the graphite tube and end caps.
Embodiments of the invention relate to methods of monitoring moisture content in a gasket material used in HPHT processing of superabrasive elements in a high-pressure cubic press and related systems. The relationship between at least one physical characteristic of the gasket material (e.g., a dissipation factor) and moisture content for a gasket material may be exploited for use in a method for performing quality control on a gasket material and HPHT processing materials to form a superabrasive element such as a PDC.
In an embodiment, a method for performing quality control on a gasket material for use in a cell assembly in a high-pressure cubic press is disclosed. In an embodiment, the method includes determining at least one physical characteristic of the gasket material using a nondestructive testing technique, and predicting a moisture content for the tested gasket material at least partially based on the at least one physical characteristic. In an embodiment, determining at least one physical characteristic of the gasket material includes determining a dissipation factor for the gasket material using an electromagnetic (“EM”) energy testing technique (e.g., a radio frequency testing technique or other suitable frequency), and predicting a moisture content for the tested gasket material includes predicting the moisture content for the tested gasket material at least partially based on the dissipation factor and a dissipation factor-moisture content calibration curve for the gasket material.
In an embodiment, if the moisture content is below a threshold level, the gasket material may be formed into one or more components of a cell assembly, such as a cube and/or gasket plugs of the cell assembly. In an embodiment, if the moisture content is above a threshold level, the gasket material may be discarded and not employed as a gasket material for a cube and/or gasket plugs of a cell assembly. In another embodiment, if the moisture content is above a threshold level, the gasket material may be heated in a furnace to bake out the moisture therein to lower the moisture content. After heating or otherwise at least partially removing the moisture content, the processed gasket material may be re-tested to measure the dissipation factor thereof. If the moisture content is below the threshold level, then the re-tested gasket material may be employed for the cube and/or gasket plugs of a cell assembly.
In an embodiment, a nondestructive testing system for determining a moisture content in a gasket material for use in a high-pressure cubic press is disclosed. The nondestructive testing system includes a sensor configured to receive a gasket material for use in a cell assembly in a high-pressure cubic press. The nondestructive testing system further includes an EM energy source operably coupled to the sensor and configured to output excitation EM energy to be received by the sensor. The nondestructive testing system further includes a computing device operably coupled to the sensor to receive one or more signals output therefrom characteristic of a response of the sensor responsive to the sensor being excited by the excitation EM energy. The computing device may be configured to determine a moisture content of the gasket material at least partially based on the one or more signals.
Features from any of the disclosed embodiments may be used in combination with one another, without limitation. In addition, other features and advantages of the present disclosure will become apparent to those of ordinary skill in the art through consideration of the following detailed description and the accompanying drawings.
The drawings illustrate several embodiments of the invention, wherein identical reference numerals refer to identical or similar elements or features in different views or embodiments shown in the drawings.
Embodiments of the invention relate to methods of monitoring moisture content in a gasket material used in HPHT processing of superabrasive elements in an HPHT cubic press and related nondestructive testing systems for performing quality control on the gasket material. The relationship between at least one physical characteristic of the gasket material (e.g., a dissipation factor) and moisture content for a gasket material may be exploited for use in a method for performing quality control on a gasket material and HPHT processing materials to form a superabrasive element such as a PDC.
In an embodiment, a calibration curve or data for a relationship between the dissipation factor and moisture content in the gasket material may be developed and/or provided. A gasket material may be tested using an EM radiation technique (e.g., radio-frequency technique, a microwave radiation technique, an ultrasound technique, an x-ray technique, or combinations thereof) to measure a dissipation factor of the gasket material. The predicted moisture content for the tested gasket material may be determined at least partially based on the measured dissipation factor and/or the calibration curve.
In an embodiment, if the moisture content is below a threshold level, the gasket material may be formed into one or more components of a cell assembly, such as a cube and/or gasket plugs of the cell assembly. In an embodiment, if the moisture content is above a threshold level, the gasket material may be discarded and not employed as a gasket material for the cube and/or gasket plugs of the cell assembly. In another embodiment, if the moisture content is above a threshold level, the gasket material may be heated in a furnace, exposed to a reduced pressure (e.g., a vacuum), otherwise processed, or combinations thereof to remove at least some of the moisture therein to lower the moisture content. After processing or drying, the gasket material may be re-tested to measure the dissipation factor thereof. If the moisture content is below the threshold level, then the re-tested gasket material may be employed for the cube and/or gasket plugs of a cell assembly.
As shown in
Attenuation of the EM energy wave 404 is indicative of moisture content of the gasket material sample, while phase shift between the EM energy 404 and the transmitted EM wave 410 is indicative of density of the gasket material sample.
Other system configurations may be employed besides the nondestructive testing system shown in
In the illustrated embodiment, the gasket material sample 712 is at least partially received in the passageway 704 of the coaxial resonator sensor 701 and the coaxial resonator sensor 701 is coupled to an EM energy source 714 (e.g., a MW energy source or a radio-frequency energy source) to receive an excitation signal output therefrom. The coaxial resonator sensor 701 receives an EM excitation energy 703 from the EM energy source 714 and the dissipated energy is output therefrom through the same input as the EM excitation energy to a computing device 716 (e.g., an analyzer) from which a Quality factor (“Q”) may be determined. The frequency of the EM excitation energy may be selected at or near a resonant frequency for the resonator. Q for the resonator changes when the gasket material sample 712 is disposed therein and further changes based on the moisture content of the gasket material sample 712. Thus, the value resonant frequency changes depending on whether the gasket material sample 712 is disposed in the passageway 704 and, consequently, the value of Q.
A dissipation factor (“D factor”) for the gasket material sample 712 may be determined based on the Qw/sample for the coaxial resonator 701 having the gasket material sample 712 disposed therein and Qempty for the coaxial resonator without the gasket material sample 712 disposed therein. For example, the D factor is equal to 1/Qw/sample−1/Qempty. It should be noted that the frequency of the received EM energy and the sensor design may be adjusted to at least one of the shape, size, properties of the gasket material, or to enhance the sensitivity and/or accuracy of the determination of the D factor.
In an embodiment, the computing device 716 includes at least one processor 718 and memory 720 storing computer executable instructions thereon. When the computer executable instructions are executed by the at least one processor 718, the at least one processor 718 may calculate the Q factors and further calculate the D factor based on the Q factors.
The relationship between the D factor and moisture content of the gasket material may be developed experimentally. The moisture content for a plurality of gasket material samples was determined and the results are shown in
The dissipation factor-moisture content calibration curve is shown in
The relationship between D factor and moisture content for the gasket material may be exploited as a method for performing quality control on a gasket material. In an embodiment, a calibration curve or data for the relationship between the D factor and moisture content in the gasket material may be developed. A gasket material may be tested using an energy dissipation technique as disclosed herein to measure the D factor thereof. The predicted moisture content for the tested gasket material may be determined based on the measured D factor and the calibration curve. For example, with reference to
In an embodiment, if the moisture content is above a threshold level, the gasket material may be scrapped and not employed as a gasket material for the cube or gasket plugs of a cell assembly. In an embodiment, if the moisture content is below a threshold level, the gasket material may be employed as a gasket material for the cube or gasket plugs of a cell assembly.
In another embodiment, if the moisture content is above a threshold level, the gasket material may be heated in a furnace, exposed to a reduced pressure (e.g., a vacuum), otherwise processed, or combinations thereof to remove at least a portion of the moisture therein to lower the moisture content. After processing, the gasket material may be re-tested to measure the D factor thereof. If the moisture content is below the threshold level, then the re-tested gasket material may be employed for the cube and/or gasket plugs of a cell assembly.
Referring to
Referring to
In an embodiment, at 1106, if the moisture content is above a threshold level, the method 1100 further includes an act 1108 of discarding the gasket material and not employing it as a gasket material for a cube and/or gasket plugs of a cell assembly. In another embodiment, at 1106, if the moisture content is above a threshold level, the method 1100 further includes heating or otherwise processing the gasket material to remove at least some of the moisture therein to lower the moisture content. After processing, the gasket material may be re-tested to measure the dissipation factor thereof in accordance with acts 1102, 1104, and 1106. At 1106, if the moisture content is below the threshold level, then the re-tested gasket material may be employed for the cube and/or gasket plugs of a cell assembly in accordance with act 1110.
In another embodiment, the predicted moisture content from act 1104 may be correlated with another nondestructive analytical technique. For example, radio frequency energy may be used in act 1102, while the other nondestructive analytical technique may employ ultrasound or other type of energy.
The method 1100 of performing quality control discussed above may also be applied to other components of the cell assembly. For example, the method of performing quality control discussed above may also be applied to the heater, graphite parts, salt, or any other portion of the cell assembly, individually or in combination.
While various aspects and embodiments have been disclosed herein, other aspects and embodiments are contemplated. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting. Additionally, the words “including,” “having,” and variants thereof (e.g., “includes” and “has”) as used herein, including the claims, shall be open ended and have the same meaning as the word “comprising” and variants thereof (e.g., “comprise” and “comprises”).
This application claims priority to U.S. Provisional Application No. 61/671,884 filed on 16 Jul. 2012, the disclosure of which is incorporated herein, in its entirety, by this reference.
Number | Date | Country | |
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61671884 | Jul 2012 | US |