WO2012071449A2

WO2012071449A2 - Architectures, methods, and systems for remote manufacturing of earth-penetrating tools

Info

Publication number: WO2012071449A2
Application number: PCT/US2011/061912
Authority: WO
Inventors: Robert E.W. Ourso
Original assignee: Drill Master Inc.
Priority date: 2010-11-22
Filing date: 2011-11-22
Publication date: 2012-05-31
Also published as: WO2012071449A3

Abstract

Methods and systems for manufacturing a part for an earth- penetrating tool comprising manufacturing the part at a remote manufacturing location using design data transmitted from another location. A customer at a customer location may submit an order for a part. The order is transmitted to a design location where a design for the part is defined. Designed data is transmitted to a remote manufacturing facility which is nearer to the customer location than is the design location. The part for an earth-penetrating tool is formed at the remote manufacturing facility using additive manufacturing. The part may be combined with preformed parts or separately formed parts to create an earth-penetrating tool.

Description

Architectures, Methods, and Systems for Remote

Manufacturing of Earth-Penetrating Tools

CROSS-REFERENCE

[0001] This application claims the benefit of U.S. Provisional applications 61/416,283 (filed November 22, 2010), 61/471 ,777 (filed April 5, 201 1), 61/473,898 (filed April 1 1 , 201 1), and 61/542,799 (filed October 4, 201 1) all of which are hereby incorporated by reference.

BACKGROUND

[0002] The present application relates to earth-penetrating implements, and more particularly to rock-penetrating drill bits used to drill hydrocarbon wells and the like.

[0003] Note that the points discussed below may reflect the hindsight gained from the disclosed inventions, and are not necessarily admitted to be prior art.

Drilling Oil and Gas Wells

[0004] Petroleum is a foundation of modern industrial civilization. To obtain petroleum, it is necessary to find it, and to drill into the Earth to extract it. Such drilling may require penetrating many thousands of feet of sedimentary rock.

[0005] Drilling oil and gas wells is a highly developed technology. In the basic rotary drilling technology, as shown in Figure 1A, a borehole is extended using a rock bit which is screwed onto a string of drill pipe. (The drill string often includes some heavier sections, near the bit, which are referred to as drill collar.) Torque is applied to the drill string (e.g. by a rotary table as shown, or by a top drive or downhole motor), so that the rock bit is forcibly rotated at the end of the borehole (the cutting face). The rock bit is pressed against the cutting face, typically by the weight of the drill string. Drilling mud is pumped through the drill string by a high- horsepower pump, and jets out through nozzles in the rock bit, to create a strong turbulent flow at the cutting face. This flow of drilling mud sweeps the broken rock (cuttings) away from the cutting face, while also cooling the rock bit. As drilling proceeds, additional sections of drill pipe are screwed onto the drill string, which can have a total length of 10,000 feet or more. The drill rig includes a powerful hoist over the borehole, which can lift the drillstring; when drilling is completed, or a bit needs to be replaced, the drillstring is lifted by this hoist, so that sections of drillpipe can be sequentially removed. Thus the drillstring is assembled in place as the bit goes down, and disassembled as the bit comes up. There are many variations in this sophisticated technology, but the basic components of drill bit operation are mud flow, torque, and axial force (often referred to as "weight on bit").

Types of Rock Bits

[0006] Reservoirs have to be drilled where they are found, so a great variety of rock structures may be encountered. Sedimentary rocks differ in many ways; for example, different kinds of rock have different compressive strengths, different shear strengths, different abrasive characteristics, and different degrees of cohesion. Petroleum engineers therefore make use of a wide range of rock bit designs. However, there are several types which are important. [0007] One of these types is a fixed-cutter bit, in which compacts of an ultrahard material (such as a cermet which includes tungsten carbide particles in a cobalt binder) are affixed to the wings of a steel body. Alternatively, the entire body can be made of a carbide/cobalt cermet. (Such bits are commonly referred to as "matrix bits." ) An example of such a bit is shown in Figure 1C.

[0008] Another type is roller cone bits, in which "cones" (generally conical elements) roll around the cutting face under a large applied axial force (coaxial with the borehole). The cones have teeth or inserts which localize force on the cutting face to cause compressive failure of the rock. An example of such a bit is shown in Figure IB.

Materials Used in Rock Bits

[0009] The very high forces (both static and transient), and the high-velocity currents of abrasive slurry near the cutting face, place extreme demands on the materials used in drill bits. Steel is not abrasion-resistant enough for many applications, so "matrix bits" are sometimes used instead. The male thread (the "pin") mates with the standard threads on the drillstring, and thus is preferably machined.

Conventional Manufacturing Techniques for Rock Bits

[00010] Earth boring tools, such as rock bits, are typically manufactured by either (1 ) in the case of matrix bits, creating a mold generally comprising a negative image of the part being produced or (2) for steel alloy bits by machining the part from a solid starting material. A mold can be created using computer aided design ("CAD") software and computer numeric control ("CNC") machines to create the negative image mold. Due to inherent clearance limitations of CNC machines, only features with a certain minimum size and spacing can be created in this manner. Certain other features can be added by combining smaller mold inserts with a main mold. Doing so adds complexity to the fabrication process and increases the risk of failure during fabrication or use. Still other features are not possible even with inserts. The mold is then filled with a material that will comprise the body of the earth-boring tool, such as metal or ceramic particles. Other earth-boring tools are manufactured by machining the tool from a larger piece of metal.

[0001 1] Manufacturing earth-boring tools according to these methods is disadvantageous because: (1 ) the process is slow, (2) customization of tool design is difficult and expensive, (3) manufacturing facilities are large and capital intensive; and (4) bit design is hampered by tooling clearance considerations; (5) graphite molds, which are necessary for casting matrix tools, can leak inside a furnace, causing major damage to the furnace and putting workers at risk of injury when removing the product from the furnace at very high temperature. Additionally, many lathes, mills, CNC and other machines have pinch points, turning chucks, rotating spindles and other moving parts that can injure or severely maim a person.

Supply-Chain Management

Drilling engineers need to choose from many different rock bit designs to meet the needs of particular jobs. A very large number of bits need to be warehoused to permit rapid response to the changing needs of active drilling sites. Since the drilling site locations are determined by geology, and not by human needs, transport of a warehoused bit to a drill site will often add significant delay and cost into the supply connection.

 SUMMARY

[00012] The present application discloses novel methods, architectures, and systems for manufacturing and supplying earth- penetrating components such as rock bits, wherein additive manufacturing capacity is provided at multiple remote manufacturing locations to permit fast turnaround of customized components.

[00013] For example, in some embodiments, a customer transmits a request for a part from a customer location, a shape for the part is defined at a design location, the part is manufactured at a remote manufacturing location by additive manufacturing.

[00014] In some but not all embodiments, a desired shape for an earth-penetrating tool is defined which comprises designs for a body portion and a threaded attachment portion, the body portion is manufactured locally (at a remote manufacturing location) by additive manufacturing, and the body portion is then combined with a prefabricated threaded attachment portion to form a rigid component which can be assembled to standard drill string components at the drilling site.

[00015] The disclosed innovations, in various embodiments, provide one or more of at least the following advantages. However, not all of these advantages result from every one of the innovations disclosed, and this list of advantages does not limit the various claimed inventions.

• Reduced requirements for inventory and logistics management;

• Faster response to critical needs;

• Just-in-time inventory management;

• Remote manufacturing ability; Allows tools to be customized for a particular drilling location or particular formations encountered during drilling;

Allows construction of smaller, cheaper tool manufacturing facilities, which can be located nearer to a drilling location; Allows for temporary or mobile tool manufacturing facilities; Simpler customization of tool design;

Combines the higher tensile strength of conventionally-forged steel with the advantages of additive manufacturing wear- resistant customizable body elements.

Better drilling fluid flow dynamics;

Increased reliability;

Faster production of new designs;

Easier testing of new designs;

Lower material costs;

Potential internal compartments to protect electronics.

Lower employee injuries.

Ability to produce many bits of the same design or different designs in the same print box at the same time.

Total, unlimited design flexibility without the restraints of conventional machine tool (CNC / MANUAL machines) limitations.

Less foot print needed on the floor space of a manufacturing facility. Equating to less overhead and with fewer employees needed to produce product by conventional machine production methods.

Faster high production rates. • Less overtime needed as machines run 24/7 without the need of a machine operator to be present at all time.

• Reduced repair cost as these machines cannot be crashed from an inattentive operator or bad CNC program. AM machines will only stop print much like a paper jam in a paper copy machine.

BRIEF DESCRIPTION OF THE DRAWINGS

[00016] The disclosed inventions will be described with reference to the accompanying drawings, which show important sample embodiments and which are incorporated in the specification hereof by reference, wherein:

[00017] Figure 1 shows an example of a fixed-cutter rock bit made by additive manufacturing.

[00018] Figure 1A illustrates a typical drill rig (earth-penetrating assembly).

[00019] Figure IB illustrates a typical roller-cone rock bit.

[00020] Figure 1C illustrates a typical fixed-cutter rock bit.

[00021] Figure 2 shows a cross-section view of a fixed cutter rock bit made by additive manufacturing.

[00022] Figure 3 is an alternative perspective view of a fixed- cutter rock bit made by additive manufacturing.

[00023] Figure 4 is a perspective view of a double-threaded sub that can be used to connect a rock bit, like that of Figure 1 , to a drill string.

[00024] Figure 5 is a cross-section view of the double-threaded sub shown in Fig. 4.

[00025] Figure 6 illustrates the combination of a fixed cutter rock bit and a double-threaded sub.

[00026] Figure 7 is a perspective view of a fixed-cutter rock bit made by additive manufacturing.

[00027] Figure 8 is a flow chart showing steps that can be performed in connection with manufacturing an earth-penetrating tool. [00028] Figure 9 is a flow chart showing steps that can be performed in connection with a particular embodiment of a method of manufacturing an earth-penetrating tool.

[00029] Figure 10 illustrates a partially-manufactured fixed- cutter rock bit during the process of additive manufacturing.

[00030] Figure 11 shows a green body for a rock bit with stilts.

[00031] Figure 12 shows a cross-section of a rock bit with a defined cavity for holding electronic components.

[00032] Figure 13 is a flow chart showing steps in one example of remote manufacturing of a rock bit.

[00033] Figure 14 is a schematic diagram of a system for remote manufacturing of earth-penetrating tools.

DETAILED DESCRIPTION OF SAMPLE EMBODIMENTS

[00034] The numerous innovative teachings of the present application will be described with particular reference to presently preferred embodiments (by way of example, and not of limitation). The present application describes several inventions, and none of the statements below should be taken as limiting the claims generally.

[00035] Conventional methods of fabrication of down-hole tools such as casting, forging, and machining require large, expensive equipment such as furnaces, presses, lathes, and CNC machines. Several types of equipment can be required for a single tool part. Other tool parts can require separate equipment. Further, the equipment requires large numbers of trained personnel and enormous amounts of energy to operate. As a result, manufacturing facilities capable of producing tools for down-hole use are physically large and require a significant capital investment. This, in turn, limits the number of locations that can be economically constructed. Additionally, such facilities can only be feasible constructed in locations with (1) a stable political environment, (2) adequate human resources, and (3) reliable, economic energy.

[00036] In contrast to the limited number of locations where down-hole tools can be produced, the tools are used all over the globe, including locations far from population centers. Thus, in many situations, transportation of a down-hole tool from a manufacturing location to a use location is slow and expensive. Because of the inherent delay involved in transportation of components over long distances to remote locations, drillers have to use down-hole tools already on site or tools that may be transported from a nearby location. Such tools may not be optimal for use in the particular drilling operation.

[00037] Equipment use to make items by additive manufacturing can be smaller and less expensive than equipment used for by casting, forging, and machining. Further, a single additive manufacturing machine can be used to produce many different parts from a variety of materials. An additive manufacturing machine can be made to produce different parts and customized variations of parts simply by changing the computer instructions provided to the machine. Those instructions may be transmitted electronically from a design location anywhere in the world. The present inventor has realized that additive manufacturing down-hole tools according to certain disclosures herein can be produced at locations much closer to the expected use location.

[00038] One class of innovative teachings contained herein relates to a method of producing down-hole tools in which a user at a user location submits a request for a down-hole tool to a provider. A designer at a design location creates or selects a tool design. The tool design is transmitted to a manufacturing location. The manufacturing location is preferably located near the user location. A tool is created at the manufacturing location from the tool design using additive manufacturing to create at least a part of the tool. In one class of embodiments, parts of the tool made by additive manufacturing are combined with standardized parts made by conventional manufacturing techniques to create a completed tool. The standardized parts can be manufactured at another location and shipped to the manufacturing location.

[00039] In another class of embodiments, the manufacturing location is on a marine vessel such as a ship (or tender or platform) . The ship can be positioned near a location where drilling activity is occurring. When no longer needed at that location, the ship can be moved to another location. This provides insulation from deficiencies of local infrastructure, as well as political uncertainties.

[00040] Another class of innovative teachings contained herein relates to ways to combine an additively-manufactured body portion with a shank (at least) which is made of more conventional materials or by more conventional methods, e.g. machined from high-carbon or high-alloy steel. The shank can also comprise or be attached to a threaded section configured to engage a drill string.

[00041] The present inventor has realized that the special properties of various additive-manufacturing techniques and components are not required for the entire mechanical structure. Instead, the present application provides ways to optimize a combined structure, in which different materials are used for different locations within the structure.

[00042] Additive manufacturing allows customized parts to be manufactured directly from a 3-D computer model without intermediate steps such as mold making, casting, forging, or machining. On the other hand, bulk quantities of standardized parts typically can be made more cheaply and with a wider variety of materials using certain conventional manufacturing techniques. Further, conventional materials and manufacturing techniques can produce parts with well-known and predictable physical properties and precise dimensions. The combination of the manufacturing speed and easy customization of additively-manufactured parts with the predictable physical properties and precise dimensions of standardized parts has been discovered to lead to improved down-hole tools. [00043] In various embodiments, the body portion can be steel particles in a matrix of a dissimilar material, or can be a fused-particulate steel mass made by laser fusion, or can be a carbide matrix material.

[00044] Another class of innovation disclosed herein relates to combining additively-manufactured bit body portions with wear-resistant parts to provide overall longevity consistent with conventional tools. In various embodiments, the wear-resistant parts can be standard-sized cutting teeth or wear buttons formed from tungsten carbide or can be hard facing applied to wear-prone portions of the tool. Parts of the tool likely to benefit from customization, such as cutting faces and fluid channels are manufactured by additive manufacturing. Tool parts made by additive manufacturing can be quickly and easily customized, since the part is manufactured directly from a 3-D computer model. Design changes can be made using computer software to create a new 3-D model. The redesigned part can be manufactured as quickly and cheaply as making another copy of the original design.

[00045] Further, parts made by additive manufacturing are freed from design constraints of traditional manufacturing techniques. For example, internal cavities can be defined within a part during additive manufacturing to save material or to provide a protected space for electronic components. Such internal cavities cannot be made with conventional manufacturing techniques.

[00046] Additionally, parts made by additive manufacturing can be made with better fluid-flow characteristics. Without design limitations imposed by convention manufacturing, such as machining clearance requirements, designers can define fluid channels with optimal flow characteristics. [00047] New designs can be subjected to real-world testing more quickly if at least part of the tool is formed using additive manufacturing. The additively manufactured part can be quickly completed to form an entire tool and then put into operation. Additional design changes, if necessary, can be made equally quickly leading to a tool with optimal design parameters. Further, design customizations for a particular drilling operation can are feasible, since the additively manufactured part can be manufactured quickly and at a location that can be near to the drilling site.

[00048] Overall material costs can be reduced because certain parts, made with additive manufacturing, can include hollow internal structures designed to reduce material usage while maintaining structural strength. Other parts can be made conventionally using the least expensive materials available which meet physical property requirements of hardness, tensile strength, etc.

[00049] Additionally, costs can be saved because raw materials can be used without the need of an outside vender producing various parts adding cost to the product. Proprietary designs and process secrets can also be keep much more secure without any outside source providing finished parts in which they sometimes must know company preparatory information.

I. Fixed-Cutter Bit

[00050] One sample embodiment, which can incorporate many of the innovations described herein, will now be described in great detail. However, it should be noted that all of the examples described herein do not necessarily limit any of the claimed inventions. Indeed, the examples are not necessarily even compatible with all of the claimed inventions. Moreover, various inventions have different synergies in different contexts, as will be described below.

[00051] Figure 1 shows an earth-penetrating apparatus 10 (hereinafter "rock bit") of a type that can be used for drilling hydrocarbon wells. Rock bit 10 is a fixed-cutter rock bit. Rock bit 10 comprises an internally-threaded section 14, fixed-cutter body 16, cutting blades 18, and sockets 22 defined in cutting blades 18. A bit breaker slot 23 is preferably defined in rock bit 10 to facilitate separation from a drill string.

[00052] Internally- threaded section 14 preferably comprises tapered female threads (not show) configured to engage a male threaded section of a double-threaded sub (discussed below in connection with Figs. 4 and 5). Internally-threaded section 14 can comprise standard thread patterns, such as American Petroleum Institute ("API") thread standards or American Standard Acme Screw Thread ("ACME") standards. Alternatively, internally-threaded section 14 can comprise any other known thread pattern or a proprietary thread pattern.

[00053] Figure 2 is a cross-section view of rock bit 10 of Fig. 1.

[00054] Figure 3 is an alternative view of the rock bit 10 of Fig. 1. Internally-threaded section 14 is more clearly illustrated in Fig. 3.

[00055] Figures 4 and 5 illustrate a threaded shaft 30 configured to attach rock bit 10 to a drill string (not shown). Threaded shaft 30 preferably comprises two threaded ends: a bit-engaging end 32, and a drill- string-engaging end. 34. Drill-string-engaging end 34 preferably comprises known thread standards, such as American Petroleum Institute ("API") thread standards or American Standard Acme Screw Thread ("ACME") standards. Rock-bit-engaging end 32 can comprises matching standard threads, or can comprise alternative standard threads or proprietary threads. Rock-bit-engaging end 32 preferable comprises threads compatible with internally-threaded section 14 of rock bit 10. Alternatively, rather than engagement by threads, threaded shaft 30 can be attached to rock bit 10 by keying, locking cam, welding, brazing, or other method.

[00056] Threaded shaft 30 preferably comprises a steel alloy such as 4140 steel and can be manufactured according to conventional techniques such as forging, casting, and machining.

[00057] Figure 6 illustrates a potential engagement of rock bit 10 with sub 30.

[00058] Figure 7 illustrates another embodiment of a rock bit 10' which in most respects is similar to rock bit 10. However, rock bit 10' does not include internally-threaded section 14. Rather, a threaded shaft 15 is integrally formed with rock bit 10'. Threaded shaft 15 preferably comprises known thread standards, such as American Petroleum Institute ("API") thread standards or American Standard Acme Screw Thread ("ACME") standards.

II. Making Earth-Penetrating Tools Using Additive Manufacturing

[00059] Figure 8 is a flow-chart illustrating one process that may be used to make earth-penetrating tools. While Fig. 8 illustrates one example process, many variations are possible. Fig. 8 is provides an overview of the process and certain example methods, apparatus and systems for carrying out steps shown in Fig. 2 are discussed in more detail below. [00060] In step 102, a design for an earth-penetrating tool is defined, preferably in a 3-D computer model. In step 104, an additive manufacturing machine is used to create a green body in the shape of at least a part for an earth-penetrating tool. The green body preferably comprises particles of a material that will partially compose the tool part, with the particles being held together by an initial binder. The green body is relatively soft at this point. Care should used when moving the part to a furnace or oven. The green body is preferably supported by materials such as quartz sands or small ceramic particles so that green part will not deform from its own weight.

[00061] In step 108, the green body is infused with a structural binder.

[00062] In step 1 18, any non-additively-manufactured components are preferably added to the earth-penetrating tool.

[00063] Figure 9 is a flow-chart illustrating another method for manufacturing an earth-penetrating tool. The method illustrated in Fig. 9 is similar to that illustrated in Fig. 8 with several additional steps. In step 105, after the green body is set into place and properly supported, stilts are preferably added in the appropriate areas to insure proper infiltration of part.

[00064] In step 106 the green body is baked to expel the initial binder and partially fuse the particles. In step 1 12, stilts are removed from the tool part.

[00065] In step 1 14, the infused tool part is optionally hardfaced for increase wear resistance. In step 1 16, tool parts made of hard material, such as cutting compacts, can be added to the tool part. In step 1 19, non- additively manufactured structural components, such as sub 30, are preferably attached. In step 122, nozzles can be installed on the earth- penetrating tool.

III. Design Generation

[00066] Referring to step 102, before an earth-penetrating tool is manufactured, it is preferably designed and defined in a 3-D computer model using computer aided design and drafting ("CADD") software. CADD software provides a user with input tools that can streamline the design, drafting, documentation, and manufacturing processes. The 3-D computer model is preferably a format compatible with an additive manufacturing machine. For example, the 3-D computer model can be in standard template library ("STL") format. STL is a C++ library of container classes, algorithms, and iterators that provides many of the basic algorithms and data structures of computer science. STL is a generic library, meaning that its components are heavily parameterized: almost every component in the STL is a template). Alternatively, model formats such as additive manufacturing file format ("AMF") can be used.

[00067] Figure 3 shows an example of a CAD model of a part for a rock bit. Once a design for an earth-penetrating tool is defined in a 3-D computer model, the design can be easily transmitted to a manufacturing facility anywhere in the world.

IV. Internal Structures

[00068] Figure 12 shows a rock bit 10" with a cavity 52 that can be defined during additive manufacturing. Cavity 52 is first defined in a 3-D computer model. During forming of bit body, material is deposited by additive manufacturing in locations surrounding cavity 52 until cavity 52 is defined in bit body.

[00069] A cavity opening 54 is similarly defined in rock bit 10. Cavity opening 54 is preferably defined as small as possible while still allowing sufficient clearance to insert the electronic component. The electronic component can be made with a flexible motherboard to allow insertion through a smaller cavity opening 54. Cavity 52 can be used to house electronic components, such as sensors, GPS units, or radio transmitters, within rock bit 10". Electronic components positioned within Cavity 52 can be protected from the violent conditions prevalent at the bottom of a well. Electronic components can be better protected using a cavity 52 built according to the present invention than a cavity made by machining or other conventional manufacturing methods because the opening can be made smaller with respect to the size of cavity 52 as it is not subject to clearance limitations inherent in machining. Using a smaller cavity opening 54 increases the protection provided to the electronic component and decreases the risk of damage to the electronic component. Additionally, cavity 52 can be formed in rock bits comprising tungsten carbide and other hard materials where machining of a cavity is not practical.

[00070] After the bit body has been formed and the electronic component placed inside, cavity 52 is preferably covered by a steel cover or can be back-filled with a resilient material, such as high-temperature epoxy. A nonconductive material is preferable if the electronic component includes any type of radio transmitter. Alternatively, the transmitter can be connected to an external antenna or can be configured to transmit through the bit body. [00071 ] Additive manufacturing can also be used to make a bit with internal spaces configured to save material or decrease the weight of an earth-penetrating tool. For example, a rock bit can be fabricated, using the above techniques, with an internal honeycomb structure. Internal honeycomb structure results in a rock bit that can be produced using significantly less raw material yet maintains structural properties similar to a solid rock bit. Internal honeycomb structure or other internal structure is preferably defined in a 3-D computer model during the design phase. Internal honeycomb structure is then preferably created in the bit body during additive manufacturing. In one example, the internal honeycomb structure can include hexagonal-closest-packed void cells with a width of about 3/8" to ¾" and a wall thickness of about .125".

V. Matrix Bit AM

[00072] Fixed-cutter bit 10 is preferably manufactured by additive manufacturing. Figure 10 shows a partially-formed fixed cutter bit. First, additive manufacturing is used to create a matrix green body comprising particles of hard material held together by an initial binder, with interstices between the particles. The particles of hard material can comprise encrusted diamond, tungsten carbide, or other hard materials, many of which are known for use in rock bits.

[00073] Generally spherical particles are preferred. Irregular and non-spherical shaped powders tend to be more difficult to print due to the low packing density after spreading which leads to under saturation and weak green parts. Powders of this nature also pack with the movement of the build and feed axes with can cause the axes to jam and stop movement. One tungsten carbide powder, GTP Body Powder, has a higher apparent density than other irregular powders due to its higher density and closer to spherical shape. The solid density of tungsten carbide is 15.8 g/cm , and this material can achieve an apparent density of 7.9 g/cm and tap density of 10.2 g/cm . This shows the possibility of 50 to 55% packing density. A particle size on the order of 60 mesh is preferable.

[00074] Stilts 82 are preferably formed as integral parts of the green body, as shown in Figure 11. During the furnace infusion step, stilts 82 will help to wick up the "binder" material (e.g. bronze) that is used to solidify the matrix green body. Stilts 82 eliminate the need for water cooling of the green body. Lengths, diameters and number of stilts are determined by the volume and size of the green part. For example, for a rock bit of about 8.5", stilts 82 can comprise generally cylindrical or square parts with length between about 2 and 15 cm and a diameter between about 2 and 15 cm.

[00075] Next, the matrix green body is baked at a temperature of about 1850 to 2180 F for about 1 hour at full temperature, although shorter or longer time can be preferably based on the volume and size of the part.

[00076] The matrix green body is then infused with a binder material such as copper and other minor alloys to create solid parts. A copper alloy (such as an alloy comprising 52.9 wt% copper and 24 wt% manganese, 15 wt% nickel and 8 wt% zinc can be used.

[00077] Finally, fixed-cutter bit 10 can have improved erosion resistance by adding hard facing material to the bit body. This can be done by conventional arc welding techniques, or by a furnace cycle to adhere a deposited coating, e.g. by heating fixed-cutter bit 10 to a temperature of between 800F and HOOF for at least 1/2 hour. [00078] Additive manufacturing machines for use with matrix tools (such as tungsten carbide) preferably uses reinforced print boxes and larger hydraulic lifters to handle heavier raw materials. The AM machine also preferably includes a powder remixer to properly recycle all unused material after each print.

VI. Steel Bit Additive Manufacturing

[00079] Fixed-cutter bit 10 is preferably manufactured by additive manufacturing with particles comprising 420 stainless steel. The stainless steel particles are first formed into a green body comprising the general shape of body 16 and cutting blades 18.

[00080] As with matrix bits, stilts 82 are preferably attached to the green body.

[00081] Next, the steel green body is baked at a temperature of about 1 HOC for about 1 hour.

[00082] The steel green body is then infused with 90-10 bronze (comprising 90 wt% copper and 10wt% tin) to create solid parts.

[00083] Depending on the alloys used, a heat treating step can also be used for hardening.

VII. Hard Elements and Hardfacing

[00084] After the additive manufacturing step, compacts 22 are rigidly attached to cutting blades 18 at pockets 24, by brazing or other attachment method. Compacts 22 preferably comprise a hard material such as tungsten carbide or polycrystalline diamond. This is particularly advantageous if the body is steel. [00085] For steel-body bits, it is also preferable in many instances to add hardfacing to portions of the surface of fixed-cutter body 16 or cutting blades 18. Hardfacing can be achieved by applying a thin layer of hard material, such as a high-alloy metal which can include particles of tungsten carbide, to portions of the surface of fixed-cutter body 16 or cutting blades 18 which are most likely to experience wear during operation. Hardfacing can be applied by conventional arc-welding methods.

[00086] In addition to compacts 22, other hardened parts can be added to fixed-cutter body 16, cutting blades 18 or other parts of rock bit 10. For example, nozzles 26, preferably comprising a hard material such as tungsten carbide cermet, can be attached to fixed-cutter body 16 after fixed- cutter body 16 is formed using additive manufacturing or other process. It is advantageous to add nozzles 26 comprising a harder material because high pressure, abrasive drilling fluid is forced through nozzles 26. Rock bit 10 will last longer and have higher performance and reliability if nozzles 26 comprise a hard material designed to withstand the abrasive fluid flow. Further, nozzles 26 can be prestocked standard sizes so that custom-designed bits can be formed and then fitted with standard nozzles 26.

[00087] For another example, inserts of harder material can be attached into the steel body after fabrication. Such inserts provide improved resistance to abrasion at points where the bit is likely to rub against the sidewalls of the borehole.

VIII. Remote Manufacturing

[00088] Figures 13 and 14 illustrate a method and system, respectively, for manufacturing of earth-penetrating tools at a location convenient to a drilling site. In step 222, a user at a drilling site 202 communicates a need for an earth-penetrating tool to a customer location 204, which can be located at, near, or far from drilling site 202. A customer at customer location 204 then submits a request for an earth-penetrating tool to a supplier at a design location 206. The request for an earth-penetrating tool preferably includes information about the particular drilling operation, such as hole diameter, drilling depth, formation properties, drilling fluid properties, drilling fluid flow rate (TFA), drilling fluid pressure, maximum weight on bit (WOB), rotary speed (RPM), type of rig, application (vertical, directional, tangent, horizontal), bottom hole assembly BHA (point the bit system, push the bit system, packed hole or the like).

[00089] In step 224, the supplier selects a design for an earth- penetrating tool that will provide optimal performance for the particular drilling operation. If no existing design meets the customer's requirement, a new design is created. Most preferably, the supplier uses software to simulate the drilling conditions to test and optimize the earth-penetrating tool design.

[00090] In step 226, after a design for an earth-penetrating tool is defined, the design is preferably transmitted to a manufacturing location 208 nearest to the drill site 202 at which the earth-penetrating tool will be used.

[00091] In step 228, the earth-penetrating tool is fabricated at manufacturing location 208 from design information transmitted from design location 206. Preferably, certain parts of the earth-penetrating tool are manufactured using additive manufacturing and other parts of the earth- penetrating tool are joined to the additively-manufactured part. For example, a body of a rock bit can be manufactured using additive manufacturing. A shaft for the rock bit is preferably joined to the body. Hardened parts such as nozzles and cutting compacts are also preferably joined to the bit body.

[00092] Parts of the earth-penetrating tool that are not manufactured by additive manufacturing are preferably standardized parts. The standardized parts can be fabricated by conventional techniques and can be manufactured at one or more standard parts manufacturing location 212 and shipped to manufacturing location 208 before the parts are needed for an earth-penetrating tool. Preferably, standardized parts are configured to be usable in a variety of earth-penetrating tool designs.

[00093] In step 229, after an earth-penetrating tool is manufactured, it is shipped from manufacturing location 208 to drill site 202.

[00094] In a preferred embodiment, an overall system for making earth-penetrating tools includes multiple manufacturing locations 208. When a customer submits an order for an earth-penetrating tool, the customer identifies the location of drill site 202. The supplier preferably transmits design information for the earth-penetrating tool to the manufacturing location 208 that is most convenient to the drill site 202.

[00095] According to various disclosed embodiments, there is provided: A method for manufacturing and supply drill bits for hydrocarbon well drilling, comprising the steps of: in response to a customer request for a drill bit for a specified location, transmitting an electronic description of the drill bit to at least one selected additive manufacturing location, which is selected, from multiple additive manufacturing locations, for ease and/or speed of delivery to the specified location; forming a drill bit body, at said selected additive manufacturing location, by additive manufacturing; and attaching one or more additional components onto said drill bit body, to thereby form a complete rock bit; wherein at least some ones of said additional components are made of a different material than said body.

[00096] According to various disclosed embodiments, there is provided: A method for manufacturing a downhole component for use in hydrocarbon well procedures, comprising the steps of: at a customer's location, transmitting a request for a downhole tool part; at a design location, defining a desired shape for a downhole tool part; at a remote manufacturing location which is closer than said design location to an end-use location, manufacturing the downhole tool utilizing the desired shape information, by a process which includes additive manufacturing.

[00097] According to various disclosed embodiments, there is provided: A method for remotely manufacturing a drill bit comprising the steps of: defining a desired shape of a drill bit assembly at a first location, the definition of the desired shape of the drill bit assembly further comprising designs for a cutter face portion and a threaded attachment portion; transmitting the desired shape via electronic communications to a second location, the second location containing additive manufacturing equipment for manufacturing the drill bit assembly; utilizing the desired shape information to form the cutter face portion by additive manufacturing; and combining a threaded portion, which is mechanically compatible with attachment to a drill string for hydrocarbon well drilling, with said body, to thereby form a complete rock bit.

[00098] According to various disclosed embodiments, there is provided: systems which imiplement any of the above methods.

[00099] According to various disclosed embodiments, there is provided: Methods and systems for manufacturing a part for an earth- penetrating tool comprising manufacturing the part at a remote manufacturing location using design data transmitted from another location. A customer at a customer location may submit an order for a part. The order is transmitted to a design location where a design for the part is defined. Designed data is transmitted to a remote manufacturing facility which is nearer to the customer location than is the design location. The part for an earth-penetrating tool is formed at the remote manufacturing facility using additive manufacturing. The part may be combined with preformed parts or separately formed parts to create an earth-penetrating tool.

Modifications and Variations

[000100] As will be recognized by those skilled in the art, the innovative concepts described in the present application can be modified and varied over a tremendous range of applications, and, accordingly, the scope of patented subject matter is not limited by any of the specific exemplary teachings given. It is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.

[000101] Alternatively to infusing the steel green body with 90- 10 alloy bronze, the green body can be infused with a heat treatable bronze alloy, such as a chrome-copper bronze. After infusion with heat treatable bronze, the body and cutting blades are heat treated as described above in connection with the discussion of additive of steel parts.

[000102] Further alternatively, the green body can be covered with a slurry of a similar material and then lightly sintered to seal the surface. Next, the green body is treated by hot isostatic pressing ("HIP") to densify the green body. Because of the large dimensional change resulting from HIP, critical dimensions and geometric features should be maintained by a ceramic fixture during the HIP process.

[000103] Other alternative processes can be used to strengthen body and cutting blades, such as liquid-phase sintering, microwave sintering, and the like.

[000104] The particulate material used for printing the green body does not have to be homogeneous, but can optionally be a mixture of materials. For one example, it is contemplated that an admixture of encrusted diamond particles with a majority of carbide/cermet particles can help to improve abrasion resistance. Diamond is generally more brittle than tungsten carbide matrix material, so a mixture which includes only some diamond material will retain more toughness than a mixture with a higher percentage of diamond might be.

[000105] Similarly, the particle size does not have to be uniform. In various embodiments, it is contemplated that a mixture of different particle sizes can improve the packing density, and/or provide additional toughness.

[000106] Some embodiments above use a honeycombed structure. However, it should also be noted that the honeycomb cell size can be varied internally as needed.

[000107] In embodiments where an additively-manufactured bit body is connected to a shank or sub, it is important to note that the connection can be done in several ways: As noted above, a double-male bit sub can be used, with the same or different threading on the two ends; but it is also possible to use a twist-locking relationship (e.g. using interrupted threads), or to use a thread-locking compound, or to use brazing instead of or in addition to mated threads.

[000108] The example shown in Figure 1 has some important advantages. Even though the final structure, in some embodiments, will be made of two or more materials, the hollow bit body of Figure 1 has a more uniform thickness than the complete final shape will have. Thus, stress and/or warping due to differential expansion under thermal cycling is minimized. Moreover, the mass of expensive powdered material (and hence the total cost) is reduced by using such a combined structure.

[000109] The description above has emphasized drill bits in particular, since this is believed to be the area of most immediate economic impact. However, it must be understood that the teachings above also apply to other types of downhole tools. One example of this is reamers.

[0001 10] None of the description in the present application should be read as implying that any particular element, step, or function is an essential element which must be included in the claim scope: THE SCOPE OF PATENTED SUBJECT MATTER IS DEFINED ONLY BY THE ALLOWED CLAIMS. Moreover, none of these claims are intended to invoke paragraph six of 35 USC section 1 12 unless the exact words "means for" are followed by a participle.

[0001 1 1 ] The claims as filed are intended to be as comprehensive as possible, and NO subject matter is intentionally relinquished, dedicated, or abandoned.

[0001 12] The claims as filed are intended to be as comprehensive as possible, and NO subject matter is intentionally relinquished, dedicated, or abandoned.

Claims

CLAIMS What is claimed is:

1. A method for manufacturing and supply drill bits for hydrocarbon well drilling, comprising the steps of:

in response to a customer request for a drill bit for a specified location, transmitting an electronic description of the drill bit to at least one selected additive manufacturing location, which is selected, from multiple additive manufacturing locations, for ease and/or speed of delivery to the specified location;

forming a drill bit body, at said selected additive manufacturing location, by additive manufacturing; and

attaching one or more additional components onto said drill bit body, to thereby form a complete rock bit;

wherein at least some ones of said additional components are made of a different material than said body.

2. The method of Claim 1 , further comprising the subsequent step of

delivering said complete rock bit to said specified location.

3. The method of Claim 1 , further comprising the subsequent step of using said rock bit, at said specified location, for drilling a hydrocarbon well.

4. The method of Claim 1 , wherein said forming step includes printing a

green body from particles of hard material, and infusing said green body, at high temperature, with a metal which fills at least some interstices in said green body.

5. The method of Claim 1 , wherein said drill bit is a fixed-cutter bit.

6. The method of Claim 1 , wherein said additive manufacture step combines particles of a metallic carbide.

7. The method of Claim 1 , wherein said attaching step unites a bit sub with said body, and said bit sub carries standard threading for connection to a drillstring.

8. A method for manufacturing a downhole component for use in

hydrocarbon well procedures, comprising the steps of:

at a customer's location, transmitting a request for a downhole tool part; at a design location, defining a desired shape for a downhole tool part; at a remote manufacturing location which is closer than said design location to an end-use location, manufacturing the downhole tool utilizing the desired shape information, by a process which includes additive manufacturing.

9. The method of Claim 8, further comprising the subsequent step of

delivering said complete rock bit to said end-use location.

10. The method of Claim 8, further comprising the subsequent step of using said rock bit, at said end-use location, for drilling a hydrocarbon well.

1 1. The method of Claim 8, wherein said manufacturing step includes

printing a green body from particles of hard material, and infusing said green body, at high temperature, with a metal which fills at least some interstices in said green body.

12. The method of Claim 8, wherein said downhole tool is a fixed-cutter bit.

13. The method of Claim 8, wherein said manufacture step combines particles of a metallic carbide.

14. The method of Claim 8, wherein said manufacturing step combines at least one component which was prestocked, and was not made by additive manufacturing, with a portion which is made by additive manufacturing.

15. The method of Claim 8, wherein said manufacturing step combines a bit sub with a body portion made by additive manufacturing.

16. The method of Claim 8, wherein said manufacturing step combines a body portion made by additive manufacturing with a threaded portion which carries standard threading for connection to a drillstring.

17. A method for remotely manufacturing a drill bit comprising the steps of: defining a desired shape of a drill bit assembly at a first location, the definition of the desired shape of the drill bit assembly further comprising designs for a cutter face portion and a threaded attachment portion;

transmitting the desired shape via electronic communications to a second location, the second location containing additive manufacturing equipment for manufacturing the drill bit assembly;

utilizing the desired shape information to form the cutter face portion by additive manufacturing; and

combining a threaded portion, which is mechanically compatible with attachment to a drill string for hydrocarbon well drilling, with said body, to thereby form a complete rock bit.

18. The method of Claim 17, further comprising the subsequent step of delivering said complete rock bit to an end-use location.

19. The method of Claim 17, further comprising the subsequent steps of delivering said complete rock bit to an end-use location, and using said rock bit, at said end-use location, for drilling a hydrocarbon well.

20. The method of Claim 17, wherein said additive manufacturing includes printing a green body from particles of hard material, and infusing said green body, at high temperature, with a metal which fills at least some interstices in said green body.

21. The method of Claim 17, wherein said rock bit is a fixed-cutter bit.

22. The method of Claim 17, wherein said additive manufacturing combines particles of a metallic carbide.

23. A system which implements the method of Claim 1.

24. A system which implements the method of Claim 8.

25. A system which implements the method of Claim 17.