权利要求：
CLAIMS1. A method of designing a mold, the mold being at least part of a unitary body to be formed from a plurality of layers by 3D printing, the method comprising: defining an inner surface of the mold corresponding to at least part of an outer surface of an object to be molded in the mold; selecting a first material from which at least part of the mold is to be printed; and selecting a second material from which at least another part of the mold is to be printed, the second material having a higher therma] and/or electrical conductivity than the first material, wherein at least one of the layers from which the mold is to be formed by 3D printing includes areas to be printed from each of the first and second materials.
2. The method of Claim 1, wherein the method further comprises: defining an outer surface of the mold corresponding at least in part to an inner surface of a container in which the mold may be installed as part of a mold assembly, the outer surface of the mold being defined so as to minimize the thickness of the mold between the inner surface and the outer surface of one or more parts of the mold whilst the mold and molded object remain removable from the container after molding the object.
3. The method of Claim 2, wherein the thickness of the mold is minimized whilst further maintaining a minimum strength of the mold as is required for handling the mold and for molding the object without breaking.
4. The method of Claim 2 or 3, wherein the material for each part of the mold is selected based, at least in part, on a likelihood of molding defects occurring at related positions within the material from which the object is to be molded, during molding of the object.
5. The method of Claim 2, 3 or 4, wherein the material for each part of the mold is selected by initially designing the mold to be formed entirely of the first material or entirely of the second material, and then substituting that material with the second material or the first material, respectively, in one or more parts in order to increase or decrease, respectively, the thermal conductivity of the mold in those one or more parts.
6. The method of Claim 5, wherein the one or more parts where the respective material is to be substituted in order to increase or decrease the thermal conductivity of the mold in those one or more parts is determined based on a likelihood of molding defects occurring in the material from which the object is to be molded in related parts of the mold cavity during molding of the object.
7. The mold of Claim 1, wherein the second material is excitable by electromagnetic radiation to generate heat and thereby to act as a heat source.
8. The method of any preceding claim, wherein the mold is initially designed to be formed entirely of the first material, and then one or more parts of the mold are re-designed to be formed of said second material in order to control the distribution of temperature and/or the direction of heat flow through the mold during molding of the object.
9. The method of any preceding claim, wherein the material for each part of the mold is selected, at least in part, based on the heat flow properties of the material or materials from which the object is to be molded.
10. The method of any preceding claim, wherein the object to be molded is an object selected from the list including: a steel bit head; a matrix bit head; a drill bit; and a piece or component of downhole equipment.
11. A unitary body formed from a plurality of layers by 3D printing, the body comprising a mold, wherein: the mold defines an internal surface corresponding to at least part of an external surface of an object to be molded in the mold; at least a part of the mold is printed from a first material; at least another part of the mold is printed from a second material, the second material having a higher thermal and/or electrical conductivity than the first material; and at least one of the layers from which the mold is formed by 3D printing includes areas printed from each of the first and second materials.
12. The unitary body of Claim 11, wherein the mold defines an outer surface corresponding at least in part to an inner surface of a container in which the mold may be installed as part of a mold assembly, one or more parts of the mold having a thickness between the inner and outer walls that is minimized whilst still permitting the mold and molded object to remain removable from the container after molding the object.
13. The unitary body of Claim 11 or 12, wherein the second material is incorporated in parts of the mold where increased heat flow into or out of the material from which the object is to be molded is desired in order to control the direction of heating and/or cooling and/or solidification of the material from which the object is to be molded.
14. The unitary body of Claim 11, 12 or 13, wherein the second material is excitable by electromagnetic radiation to generate heat and thereby to act as a heat source.
15. The unitary body of any one of Claims 11 to 14, wherein the object to be molded is an object selected from the list including: a steel bit head; a matrix bit head; a drill bit; and a piece or component of downhole equipment.
16. A method of printing a unitary body from a plurality of layers by 3D printing, the body comprising a mold having an internal surface corresponding to at least part of an external surface of an object to be molded in the mold, the method comprising depositing and bonding in selected areas a plurality of layers of materials to form the body, wherein: the materials include a first mold material from which at least part of the mold is to be printed and a second mold material from which at least another part of the mold is to be printed, the second mold material having a higher thermal and/or electrical conductivity that the first mold material; and at least one of the layers from which the body is formed by 3D printing includes areas in the layer to be printed from each of the first and second materials.
17. The method of Claim 16, wherein the materials from which the body is formed are selectively deposited in specified areas in each layer.
18. The method of Claim 16, or 17, wherein the materials from which the body is formed are selectively bonded in specified areas in each layer.
19. The method of Claim 16, 17 or 18, wherein the object to be molded is an object selected from the list including: a steel bit head; a matrix bit head; a drill bit; and a piece or component of downhole equipment.
20. A method of designing a mold assembly including a container and a mold, at least portions of an outer surface of the mold corresponding to an inner surface of the container such that the container will support the mold therein, in use of the mold for molding an object, the mold assembly defining a mold cavity substantially corresponding to the outer shape of the object to be molded, the method including: specifying at least one material from which the mold is to be formed from a plurality of layers by 3D printing; and specifying at least another material to be positioned in at least part of a space inside the container which is defined by the mold and is separate from the mold cavity, the other material having a thermal and/or electrical conductivity different from that of the one material, to adjust the heat flow through the mold at the position adjacent said another material during molding of the object.
21. The method of Claim 20, wherein the space is between the mold and the inside of the container.
22. The method of Claim 20 or 21, wherein the at least another material is positioned in a space created by a displacement that forms part of the mold, the displacement defining a negative image of at least part of a recessed portion of the object to be molded, wherein the method includes at least partially minimizing the wall thickness of the displacement so as to form the space between the outer wall of the mold and the inner wall of the container.
23. The method of Claim 20, wherein the mold includes an elongate displacement inside the mold cavity to define a fluid passageway through the object to be molded, the space being defined inside the elongate displacement.
24. The method of Claim 20, 21, 22 or 23, wherein the space provides a flow channel through which heating or cooling fluids may be passed to control heat flow through the material from which an object is to be molded in the mold.
25. The method of any one of Claims 20 to 24, wherein the at least another material is positioned in contact with the mold in parts of the mold assembly where increased heat flow through the mold is desired in order to control the direction of heating and/or cooling and/or solidification of the material from which the object is to be molded.
26. The method of any one of Claims 20 to 25, wherein the at least another material forms part of a heat source for selectively supplying heat to the mold assembly.
27. The method of Claim 26, wherein the at least another material is excitable by electromagnetic radiation to generate heat and thereby to act as a heat source.
28. The method of any one of Claims 20 to 27, wherein the material for each part of the mold assembly is selected based on the material or materials from which the object is to be molded.
29. The method of any one of Claims 20 to 28, wherein the material for each part of the mold assembly is selected based on a likelihood of molding defects occurring in the material from which the object is to be molded in related parts of the mold cavity during molding of the object.
30. The method of any one of Claims 20 to 29 including minimizing the thickness of the mold whilst ensuring that the mold and molded object remain removable from the container after molding the object, such that the container can be used more than once for molding an object.
31. The method of Claim 30, wherein the thickness of the mold is minimized whilst further maintaining a minimum strength of the mold as is required for handling the mold for assembling the mold assembly and for molding the object without breaking.
32. The method of any one of Claims 20 to 31, wherein the object to be molded is an object selected from the list including: a steel bit head; a matrix bit head; a drill bit; and a piece or component of downhole equipment.
33. A mold assembly including a container and a mold, at least portions of an outer surface of the mold corresponding to an inner surface of the container such that the container supports the mold therein for molding an object, the mold assembly defining a mold cavity substantially corresponding to the outer shape of the object to be molded, wherein: the mold is formed from a plurality of layers of at least one material by 3D printing; and at least another material is positioned in at least part of a space inside the container which is defined by the mold and is separate from the mold cavity, the other material having a thermal and/or electrical conductivity different from that of the one material.
34. The mold assembly according to Claim 33, wherein the space is between the mold and the inside of the container.
35. The mold assembly of Claim 34, wherein the at least another material is positioned in a space created by a displacement that forms part of the mold, the displacement defining a negative image of at least part of a recessed portion of the object to be molded, wherein the wall thickness of the displacement is at least partially minimized so as to form the space between the outer wall of the mold and the inner wall of the container.
36. The mold assembly of Claim 33, wherein the mold includes an elongate displacement inside the mold cavity to define a fluid passageway through the object to be molded, the space being defined inside the elongate displacement and having therein the at least another material having a thermal and/or electrical conductivity different from that of the at least one material from which the mold is to be printed.
37. The mold assembly of Claim 33, 34, 35 or 36, wherein the thickness of the mold is at least partially minimized whilst ensuring that the mold and molded object remain removable from the container after molding the object.
38. The mold assembly of one of Claims 33 to 37, wherein the at least another material forms part of a heat source for selectively supplying heat to the mold assembly.
39. The mold assembly of Claim 38, wherein the at least another material is excitable by electromagnetic radiation to generate heat and thereby to act as a heat source.
40. The mold assembly of any one of Claims 33 to 39, wherein the at least another material is positioned in contact with the mold.
41. The mold assembly of any one of Claims 33 to 40, wherein the object to be molded is an object selected from the list including: a steel bit head; a matrix bit head; a drill bit; and a piece or component of downhole equipment.
42. A method of manufacturing a mold assembly including a container and a mold, at least portions of an outer surface of the mold corresponding to an inner surface of the container such that the container will support the mold therein, in use of the mold for molding an object, the mold assembly defining a mold cavity substantially corresponding to the outer shape of the object to be molded, the method including: installing in the container (i) a mold formed from a plurality of layers of at least one material by 3D printing and (ii) at least another material positioned in a space defined by the mold inside the container, wherein the other material has a thermal and/or electrical conductivity different from that of the one material.
43. The method of Claim 42, wherein the mold includes at least one elongate displacement which is installed inside the mold cavity to define a fluid passageway through the object to be molded, the space being defined inside the elongate displacement and having therein the at least another material having a thermal and/or electrical conductivity different from that of the at least one material from which the mold is to be printed.
44. A method of molding an object including heating and/or cooling a body of material in a mold assembly, the method including controlling the heating and/or cooling of the body of material by selectively supplying heat from a heat source disposed within the mold assembly.
45. The method of Claim 44, wherein the mold assembly includes a mold and the heat source is disposed in the mold or in a space substantially defined by the mold.
46. The method of 44 or 45, wherein selectively supplying heat includes (directly or indirectly) selectively controlling the rate at which heat is supplied by the heat source and/or selectively supplying heat for certain time periods and not supplying heat for other time periods, during the heating and/or cooling of the body.
47. The method of Claim 44, 45 or 46, wherein heat is supplied from the heat source by exciting the heatsource by applying an electromagnetic field.
48. The method of any one of Claims 44 to 47, wherein the heat source includes an element selected from the list including: a thermally conductive channel for conducting heat into the mold assembly from a hotter region outside the mold assembly; an induction heating element; a glow bar; and a bar heater.
49. The method of any one of Claims 44 to 48, wherein the heat source is disposed in a displacement that extends into and/or through the mold cavity.
50. A method of molding an object including heating and/or cooling a body of material in a mold designed according to the method of any one of Claims 1 to 10.
51. A method of molding an object including heating and/or cooling a body of material in a mold assembly including the unitary body of any one of Claims 11 to 15.
52. A method of molding an object including heating and/or cooling a body of material in a mold assembly including a unitary body designed by the method of any one of Claims 16 to 19.
53. A method of molding an object including heating and/or cooling a body of material in a mold assembly designed according to the method of any one of Claims 20 to 32.
54. A method of molding an object including heating and/or cooling a body of material in a mold assembly according to any one of Claims 33 to 41.
55. A heating device including a heat source for use in molding an object in a mold assembly, the heat source being disposed within a displacement forming part of the mold assembly for forming a recess in or flow passage through the object to be molded.
56. The heating device of Claim 55, wherein the displacement is formed from consolidated sand.
57. An object molded using the heating device of Claim 55 or 56.
58. A method of molding an object comprising heating and/or cooling material from which the object is to be formed in a mold assembly that includes the heating device of Claim 55 or 56, wherein the method includes controlling the heating and/or cooling, at least in part, by supplying heat to the mold assembly with the heating device.