Mid-position bypass mud hammer

Abstract

This invention relates to a mud hammer, comprising: a piston cylinder including at least one outlet configured to receive a single-flow drilling fluid comprising drilling mud; a piston positioned within the piston cylinder and configured to be reciprocated by a first portion of the drilling fluid; a bypass pipe disposed through the piston and in fluid communication with the drill bit; an adjustable valve assembly configured to divert a second portion of the drilling fluid into the bypass pipe; and a wear-resistant bushing positioned to prevent contact between the piston and the piston cylinder, wherein the second portion of the drilling fluid diverted to the bypass pipe is discharged from the drill bit, and the first portion of the drilling fluid is discharged from the piston cylinder through the outlet in a direction away from the drill bit.

Description

Technical Field

[0001] This invention relates to a fluid or mud hammer, a mud hammer system, and a deep well drilling method. Background Technology

[0002] With increasing demand for new, emission-free, renewable, baseload geothermal energy supplies, operators are forced to drill deeper to find sufficient heat for thermal energy production. Deeper drilling, especially onshore, is often associated with higher costs, largely due to reduced mechanical rotational speeds (ROP). Deeper drilling is typically linked to harder rock, overpressured reservoirs, and higher hydrostatic pressures, which require harder rock and greater mud weight, leading to reduced mechanical rotational speeds. Typical rotary mud drilling methods can perform poorly in hard rock formations. For example, they may drill slower and have shorter bit lives than expected, increasing operating costs in hard rock. To improve drilling performance in hard rock, percussion drilling systems combining fluid or mud hammers with drill bits have been developed.

[0003] Fluid or mud hammer systems convert some of the power from the drilling fluid into mechanical force to drive the drill bit into the formation. The impact force generated by the piston movement striking the drill bit can increase the mechanical rate of penetration (MRP) in hard rock by more than 500%. However, the mud additives in the drilling fluid required for well control and cuttings transport to the surface cause high wear on the moving parts of the fluid hammer. This high wear on the working parts, along with the limited amount of fluid pumped by a typical fluid hammer to remove cuttings from the bottom of the well, are significant drawbacks of typical fluid hammer systems, making them unsuitable for deep well drilling. Therefore, the only method generally used remains the rotary tri-cone drilling method. However, the low RPP and high cost of the typical rotary tri-cone method, at least to some extent, hinder the development of geothermal energy production in most countries that require deep hard rock wells to achieve the geothermal levels needed for power generation, desalination, heating, cooling, and wastewater treatment.

[0004] A typical fluid hammer system is a dual-circulation water hammer or fluid hammer (“DC fluid hammer”), such as the system disclosed in U.S. Patent Application Publication No. 2018 / 0044991A1. The DC fluid hammer uses a dual-circulation drill pipe system to separate drilling mud from clean water. Clean water, typically injected into the drill pipe annulus, is pumped under pressure to operate the water hammer. This clean water operation can help extend the work time between servicing and rebuilding the DC fluid hammer. When operators drill deeper wells, a higher viscosity of drilling mud is required to transport drill cuttings to the surface and prevent formation fluids, including high-pressure gas, from entering the well. High-viscosity drilling mud is typically pumped into the inner tube of the drill pipe system and delivered to the DC fluid hammer's bit face through the inner tube of the DC fluid hammer. This prevents mud from flowing over the working parts of the DC fluid hammer, thus preventing wear on the components. The clean water and drilling mud mix together after leaving the DC fluid hammer and push drill cuttings towards the surface.

[0005] However, typical DC fluid hammers have many drawbacks. It has been found that when drilling deep wells using drilling mud, DC fluid hammers wear out faster than expected and fail to function effectively for the required time. For example, it has been found that even water flowing through the working parts of a DC fluid hammer can wear them down.

[0006] Another drawback of typical DC fluid hammers used for drilling deep wells is the large amount of mud loss. When the total mixed flow is discharged from the well along with drill cuttings, a certain proportion of the total fluid must be cleaned to a surface of approximately 3 to 10 micrometers before it can be pumped under pressure into the tubing to operate the DC fluid hammer. This proportion is typically around 20% to 50% of the total fluid volume transported under pressure along the drill pipe. The mud and drilling additives extracted from this proportion of the total fluid must be reintroduced into the drilling mud flow, which is pumped into the inner tubing of the DC hammer and mixed with the clean water discharged from the bottom of the well. The amount of mud that must be returned can be substantial, resulting in excessively high operating costs for the DC fluid hammer, potentially exceeding the cost of replacing the entire DC fluid hammer itself daily.

[0007] Another drawback of a typical DC fluid hammer is that its operation requires a dual-circulation drill pipe, from which the DC fluid hammer can receive two separate flows. One flow is clean water, and the other contains drilling mud and additives. The clean water flow operates the DC hammer, while the drilling mud is directed to the drill bit face. However, the dual-circulation drill pipe increases the complexity of drilling system operation, at least because it is not certified by the American Petroleum Institute (API).

[0008] Operating a drilling system using drill pipe that is not API certified can increase the risk of equipment injury or damage, such as to the inner tubing used to deliver mud to the bottom of the well. Therefore, such a system cannot provide an adequate level of safety. For example, in at least some instances, using drill pipe that is not API certified (e.g., dual-circulation drill pipe) makes it mechanically difficult, or even impossible, to include a typical internal blowout preventer (IBOP). As those skilled in the art know, an IBOP can be a short section located below the top drive that can be remotely or manually shut off in the event of an emergency or blowout. Without an IBOP, the inner tubing that delivers mud to the bottom of the well provides an unrestricted and unconstrained pathway for hazardous gases ejected to the surface. Furthermore, it is difficult, or even impossible, to add an internal safety system to the inner tubing. Operating a drilling system using drill pipe that is not API certified can also increase the operating costs of the drilling system (e.g., some insurance companies will not cover wells for safety reasons unless the driller uses API certified drill pipe and safety systems). Consequently, typical operators do not use drill pipe that is not API certified, thus reducing the use of DC fluid hammers.

[0009] An additional drawback of at least part of the typical mud hammer is so-called retrinding. Regrinding refers to the process where the rock being drilled is not flushed off the drill bit face, causing the drill bit to repeatedly retrind, impact, and grind the same rock material until it becomes a paste. This is due to the limited volume of fluid that can be pushed through the working section of a typical fluid hammer, water hammer, or mud hammer and discharged through the drill bit opening, resulting in extremely slow drilling volume or rate of drilling, and premature drill bit failure. For example, retrinding can cause a water hammer, fluid hammer, or mud hammer drill bit to fail after only 20 meters (65.5 feet), when it was supposed to last 400 meters (1312.3 feet) or more.

[0010] By diverting drilling mud to the bit face, a typical DC fluid hammer helps enhance flushing and reduce regrinding. However, operation of a typical DC fluid hammer can result in excessive fluid or mud (e.g., 70% to 80% of the total fluid volume) being transported to the bit face. It has been found that when excessive fluid or mud is transported to the bit face, a high-pressure fluid pad can form under the bit, significantly reducing the productivity of the DC fluid hammer. Similarly, it has been found that reducing the mud flow through the inner tube of a typical DC fluid hammer to address the high-pressure fluid pad problem results in insufficient total drilling fluid to lift or transport drill cuttings to the surface. Therefore, it has been found that a bypass sub must be installed above the DC fluid hammer and typical water hammer, fluid hammer, or mud hammer to deliver sufficient mud volume into the well to lift drill cuttings to the surface. The high flow rate from the bypass sub above the hammer restricts the flow of fluid attempting to transport drill cuttings from below. In addition, at least some typical fluid hammers, water hammers, mud hammers, or DC fluid hammers are limited to only 20% of the total flow rate or to this operation only. On a 12-inch (30.48 cm) diameter DC fluid hammer, the total flow rate is approximately 200 to 300 gallons per minute, which is far less than the approximately 1,000 gallons per minute required to drill a 12.5-inch diameter well to a depth of 5,000 meters.

[0011] Therefore, a mud hammer drilling system that can at least solve the above-mentioned defects is desired. Summary of the Invention

[0012] This application generally relates to a mud hammer, a mud hammer system, and a safe and feasible percussion drilling method for deep wells that is more efficient than typical fluid hammers, mud hammers, and water hammers.

[0013] The term “took out drill string” or “performed a take-out drill string” is understood to describe the physical act of removing or pulling the drill string out of the borehole for adjustment or replacement of worn-out parts, and then returning the drill string to the borehole.

[0014] In a first aspect, the present invention provides a mud hammer, comprising: a piston cylinder configured to receive a single-flow drilling fluid comprising drilling mud, the piston cylinder including at least one outlet for discharging the drilling fluid to the outside of the mud hammer; a piston positioned within the piston cylinder and configured to be moved reciprocally by a first portion of the drilling fluid; a bypass pipe disposed through the piston and in fluid communication with a percussion drill bit; an adjustable valve assembly configured to divert a second portion of the drilling fluid into the bypass pipe; and a wear-resistant bushing positioned to prevent contact between the piston and the piston cylinder, wherein the second portion of the drilling fluid diverted to the bypass pipe is discharged from the drill bit, and the first portion of the drilling fluid operating the piston is discharged from the piston cylinder through the outlet, away from the drill bit.

[0015] In one embodiment, a mud hammer is provided, comprising a piston cylinder and configured to operate using drilling fluid, including drilling mud. The piston is positioned within the piston cylinder and configured to move in a reciprocating motion over a piston stroke length. A bypass pipe passes through the piston positioning. A valve assembly is configured to allow a predetermined amount of fluid to flow into the bypass pipe. A wear-resistant bushing is positioned to prevent contact between the piston and the piston cylinder. The drill bit is in fluid communication with the bypass pipe.

[0016] In a second aspect, the present invention provides a system comprising: a single-flow drill pipe configured to transport a single-flow drilling fluid comprising drilling mud; and a mud hammer in fluid communication with the single-flow drill pipe, the mud hammer comprising: a piston cylinder including at least one outlet for discharging drilling fluid to the outside of the mud hammer; a piston positioned within the piston cylinder and configured to be reciprocated by a first portion of the drilling fluid; a bypass pipe disposed through the piston and in fluid communication with a percussion drill bit; an adjustable valve assembly configured to divert a second portion of the drilling fluid into the bypass pipe; and a wear-resistant bushing positioned to prevent contact between the piston and the piston cylinder, wherein the second portion of the drilling fluid diverted to the bypass pipe is discharged from the drill bit, and the first portion of the drilling fluid actuating the piston is discharged from the piston cylinder through the outlet, away from the drill bit.

[0017] In one embodiment, a system is provided including a single-flow drill pipe configured to deliver a single-flow drilling fluid, including drilling mud. The system may also include a mud hammer in fluid communication with the single-flow drill pipe. The mud hammer is configured to operate using drilling fluid, including drilling mud, and includes a piston cylinder. A piston is positioned within the piston cylinder and configured to move in a reciprocating motion over a piston stroke length. A bypass pipe passes through the piston positioning. A valve assembly is configured to allow a predetermined amount of fluid to flow into the bypass pipe. A wear-resistant bushing is positioned to prevent contact between the piston and the piston cylinder. The drill bit is in fluid communication with the bypass pipe.

[0018] In a third aspect, the present invention provides a drilling method comprising: positioning a mud hammer in a well, the mud hammer comprising: a piston cylinder including at least one outlet configured to discharge drilling fluid to the outside of the mud hammer; a piston positioned within the piston cylinder and configured to reciprocate in motion operated by a first portion of the drilling fluid; a bypass pipe disposed through the piston and in fluid communication with an impact drill bit having a drill bit face; an adjustable valve assembly configured to divert a second portion of the drilling fluid into the bypass pipe; and a wear-resistant bushing positioned to prevent contact between the piston and the piston cylinder; directing a single flow of drilling fluid, comprising drilling mud, to the mud hammer via a single-flow drill pipe; and operating the mud hammer to drill in the well, wherein the second portion of the drilling fluid diverted to the bypass pipe is discharged from the drill bit face, and the first portion of the drilling fluid operated by the piston is discharged from the piston cylinder through at least one outlet, away from the drill bit.

[0019] In one embodiment, the method includes positioning a mud hammer in a well. The mud hammer is configured to operate using drilling fluid, including drilling mud, and includes a piston cylinder. A piston is positioned within the piston cylinder and configured to move in a reciprocating motion over a piston stroke length. A bypass pipe passes through the piston positioning. A valve assembly is configured to allow a predetermined amount of fluid to flow into the bypass pipe. The predetermined amount of fluid flowing into the bypass pipe includes a first portion of the drilling mud in the drilling fluid. A second portion of the drilling mud in the drilling fluid flows into the mud hammer outside the bypass pipe to operate the mud hammer. A wear-resistant bushing is positioned to prevent contact between the piston and the piston cylinder. A drill bit is in fluid communication with the bypass pipe and has a drill bit face. A single-flow drilling fluid, including drilling mud, is directed to the mud hammer through a single-flow drill pipe. The mud hammer is operated to drill in the well. The first portion of the drilling mud is discharged outside the mud hammer at the drill bit face. Attached Figure Description

[0020] Figure 1 A cross-sectional view of a drilling system according to one aspect of the present invention is shown.

[0021] Figure 2 An exploded view of a mud hammer according to another aspect of the invention is shown.

[0022] Figure 3 It shows Figure 2 A perspective view of a mud hammer shown in the image.

[0023] Figure 4 A flowchart of a drilling method according to one aspect of the present invention is provided. Detailed Implementation

[0024] The term "short section" as used in this article is understood as a substructure. This is a general term applicable to many small parts of the drill string, such as short drill collars, cross joints, floating short sections, lifting short sections, bit short sections, inlet short sections, and circulation short sections.

[0025] This invention relates to mud hammers 100 and 200, which offer longer lifespans and superior performance compared to typical fluid hammers and water hammers. For example, the provided mud hammers can have longer lifespans and superior performance for deep well drilling compared to typical fluid hammers and water hammers. In another example, the provided mud hammers can have longer lifespans and superior performance for drilling in hard rock formations compared to typical fluid hammers and water hammers. The provided mud hammers are configured to operate using high-viscosity fluids (e.g., 50 microns) and are operated by drilling fluids comprising drilling mud (e.g., replacing clean water as in DC fluid hammer designs). For example, the provided mud hammers can include larger gaps between their components than at least some typical fluid hammers, thereby enabling the provided mud hammers to operate through drilling fluids.

[0026] Single-flow drilling fluid 14 is delivered to the mud hammer 100 via a standard single-flow drill pipe 12. Typical single-flow drill pipe is API certified, thus improving the safety and ease of use of the mud hammer compared to typical mud hammers (e.g., DC fluid hammers) that use non-API-approved, non-permitted types of drill pipe (e.g., dual-circulation drill pipes). For example, the mud hammer 100 can use an internal blowout preventer (IBOP). Additionally, operating the mud hammer with drilling fluid does not result in the high mud loss rates typically seen with DC fluid hammers because the mud hammer 100 does not require finely filtered water compared to typical DC fluid hammer operations.

[0027] The provided mud hammers 100 and 200 include a piston 106 that moves in a reciprocating motion within a piston cylinder 102. A valve assembly 132 controls the flow of drilling fluid in the mud hammer 100, thereby causing the piston to move. In this example, the valve assembly 132 that causes the piston to move also moves in a reciprocating motion. One drawback of operating a mud hammer with drilling mud is that, during mud hammer operation, the drilling mud tends to wear down these moving parts faster than expected (e.g., one of the problems that DC fluid hammers attempt to address).

[0028] To help address durability issues caused by drilling mud, the mud hammer 100 may include a wear-resistant bushing 134 to prevent or at least reduce contact between the piston cylinder 102 and the piston 106 of the mud hammer. In some embodiments, the mud hammer may include a secondary wear-resistant bushing 136 to prevent contact between the piston cylinder 102 of the mud hammer and the valve assembly 132 that causes piston movement. One or more wear-resistant bushings help prevent wear on internal components of the mud hammer, thereby extending component life before replacement is required. One or more wear-resistant bushings 134, 136 are replaced when they have sufficiently degraded. For example, one or more wear-resistant bushings 134, 136 may be designed to last for approximately the same duration as the expected lifespan of the mud hammer drill bit 108, allowing for simultaneous replacement of the wear-resistant bushings 134, 136 and the drill bit 108.

[0029] Pulling or retrieving the mud hammer 100 from the well is a time-consuming process. Therefore, replacing one or more wear-resistant bushings 134, 136 simultaneously with replacing the drill bit 108 improves the operational efficiency of the mud hammer compared to pulling it out of the well in two separate steps. Furthermore, the operational cost of replacing one or more wear-resistant bushings 134, 136 is significantly lower (e.g., one-tenth the cost) compared to the drilling mud losses associated with a typical DC fluid hammer. Therefore, the mud hammers 100, 200 offer greater efficiency and operational safety compared to a typical DC fluid hammer.

[0030] Mud hammers 100 and 200 include a bypass pipe 104 in fluid communication with the drill bit 108. Drilling fluid 14, including drilling mud, delivered to the mud hammers 100 and 200 can flow through the bypass pipe 104 and be discharged at the drill face 120. Thus, compared to a typical mud hammer, the bypass pipe 104 increases the flow rate of drilling mud to the drill face, thereby improving flushing at the drill face 120 and limiting regrinding.

[0031] Another valve assembly 130 is provided to control the amount of drilling fluid 14 flowing into and through the bypass pipe 104 (in Figure 1 The cross-sectional view is shown as intermediate flow 16. A single-flow drilling fluid 14 is connected to a single-flow drill pipe 12, where a portion of flow 16 is diverted to bypass pipe 104. The amount of drilling fluid diverted can be varied by selecting one of several valve assemblies 130. When a valve assembly 130 with a large diameter is selected, a larger portion of the drilling fluid 14 is directed into bypass pipe 104, while a smaller amount of drilling fluid 14 is directed to the operation of piston 106 (in...). Figure 1 (As shown in the diagram as flow 18A and flow 18B). When a valve assembly 130 with a smaller orifice (e.g., 5 mm in diameter) is selected from multiple valve assemblies 130, a larger portion of the drilling fluid 14 is directed to the operation of the piston 106, while a smaller portion of the drilling fluid 14 is directed to the bypass pipe 104.

[0032] Reducing the size of valve assembly 130 (and thus the inlet to bypass pipe 104) will increase the proportion of drilling fluid directed to the working parts of hammer 100. At a given pressure and flow rate, for example, 1000 US GPM (US gallons per minute) at 2000 psi D / T at 6000 meters, reducing the borehole diameter will increase this proportion of drilling fluid, for example, from 30% to 35%, while reducing the flow rate of drilling fluid to the drill bit face from 70% to 65%. The reduced borehole diameter of valve assembly 130 will increase the hammer's strength, allowing it to achieve greater impact force at a given flow rate. Therefore, when the rig's capacity is only 1000 GPM and increased piston impact force and / or impact rate are required to break hard rock formations, reducing the (inner tube) borehole diameter of valve assembly 130 is an adjustment option for extending drill bit life and increasing mechanical drilling speed. Increasing the amount of drilling fluid 18A, 18B driving piston 106 can also provide a higher circulation rate for piston 106. The maximum piston circulation rate is approximately 25 cycles per second. Conversely, reducing the amount of drilling fluid 18A and 18B driving piston 106 can reduce the piston circulation rate to a minimum of approximately 10 cycles per second.

[0033] If the geological conditions are soft, increasing the diameter of valve assembly 130 (into bypass pipe 104) is beneficial. This results in a lower hammer impact force and an increased flow rate of drilling fluid through bypass pipe 104 to the drill bit face, which helps flush / remove drill cuttings because the softer geological conditions allow for faster drilling speeds. This means that more drill cuttings from the annulus will be pushed to the surface, so the increased flow rate to the drill bit will help move this extra weight / volume of cuttings. The impact rate of piston 106 can also be increased by increasing the pressure and volume of drilling fluid pumped from the rig on the surface. This can be achieved without changing or adjusting valve assembly 130 (the inlet of bypass pipe 104). For example, if the driller wants to increase the impact rate of piston 106 from 18 BPS (18 impacts per second) to 20 BPS, the driller can increase the revolutions per minute (RPM) of the mud pump, thereby increasing the flow rate and pressure of drilling fluid to hammer 100. This adjustment can be made continuously or intermittently during drilling to maintain the optimal impact rate.

[0034] Before the mud hammer 100 is positioned in the well, valve assembly 130 is selected and fitted onto the mud hammer, and this valve assembly remains in place until the mud hammer is removed from the well to replace any of the wear-resistant bushings 134, 136 and drill bit 108. At this point, before reinsertion into the well, the mud hammer can be modified to adjust valve assembly 130, considering whether it is necessary to increase the piston circulation rate or increase the drilling fluid diversion to bypass pipe 104 to flush drill cuttings.

[0035] exist Figure 1 In the diagram, valve assembly 130 is shown in cross-section, where the single flow 14 splits into an intermediate flow 16 that branches off to bypass 104, and outer flows 18A, 18B. The intermediate flow 16 enters bypass 104 and then coaxially passes through secondary valve assembly 132 and piston 106. Flow 16 is transmitted through bypass 104 and discharged at drill face 120 as multiple discharge flows 124A, 124B.

[0036] Simultaneously, the outer flows 18A, 18B of drilling fluid are led from the outside of the bypass pipe 104 to the valve assembly 132 protected by the wear-resistant bushing 136. The outer flows 18A, 18B can be forced around and / or through the piston 106, and can leave the piston cylinder 102 and / or piston 106 (through port 140) before being discharged through the discharge ports 110A, 110B to form one or more discharge flows 112A, 112B.

[0037] exist Figure 2In the diagram, valve assembly 130 is shown as a pipe or tube with a flared end for mating with the receiving end of bypass pipe 104, and a pair of O-rings 202 are sealed between valve assembly 130 and bypass pipe 104. The inner diameter of valve assembly 130 can be as small as 5 mm. The inner diameter of the valve assembly can be increased from 5 mm to 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, and even to approximately 50 mm in a 12-inch mud hammer. In an 18-inch mud hammer, the outer diameter of valve assembly 130 can be increased to approximately 75 mm.

[0038] Limiting the amount of drilling fluid 14 delivered to the drill face 120 can help avoid high-pressure cushion problems caused by excessive drilling fluid or mud being delivered to the drill face. Valve assembly 130 is selectively configured such that 40% to 80% of the total delivered drilling fluid and mud can pass through bypass 104 and be delivered to the drill face 120. In some embodiments, valve assembly 130 may be a component of bypass 104. In some embodiments, valve assembly 130 may be configured such that the amount of fluid that can flow into and through bypass 104 is adjustable, for example, by having an adjustable orifice or diaphragm to selectively increase or decrease the flow rate. Furthermore, valve assembly 130 can be adjusted by changes in pressure in the delivered drilling fluid. For example, valve assembly 130 may be configured to be fully open at 2000 psi and gradually close as drilling fluid pressure decreases. Conversely, valve assembly 130 may be configured to gradually close as pressure increases.

[0039] In some embodiments, this adjustment can be made when selecting valve assembly 130 from a plurality of valve assemblies of different sizes. In these respects, the adjustability of valve assembly 130 provides the drilling operator with the ability to control the amount of fluid flowing into bypass pipe 104 based on different drilling conditions and geology. The remaining portion of drilling fluid delivered to mud hammer 100 that does not flow through bypass pipe 104 is pushed under pressure into mud hammer 100 to operate the mud hammer. When valve assembly 130 is selected from a plurality of valve assemblies of different sizes, it is selected and installed on the surface before the hammer is drilled into the well using a new drill bit 108. Therefore, the valve assembly will be held at a set opening, for example, 30 mm, before the driller selects to adjust it. The driller will select the valve assembly based on the performance of the hammer 100 during the previous 400-meter drilling operation and the condition of the last drill bit 108 drilled between 300 and 1000 meters, depending on the geological conditions (thereby determining the required diameter for access to the bypass pipe 104).

[0040] Compared to typical water hammers or fluid hammers that can only deliver a total of approximately 200 to 400 gallons (GPM) (757.1 to 1514.2 liters (LPM) per minute) to the drill face, the inventors have discovered that a 12-inch (30.48 cm) diameter mud hammer 100 can deliver a total of approximately 800 to 1000 GPM (3028.3 to 3785.4 LPM). When referring to a 12-inch mud hammer, it should be understood that the hammer's outer diameter (OD) is 12 inches. A 12-inch hammer can have a barrel diameter of approximately 11 inches, thus allowing the use of 12-inch drill bits, which are among the smallest drill bits available. Typically, 12-inch hammers use drill bits ranging from 12 inches to 17 inches.

[0041] In one example, the total transport flow rate may include 300 GPM (1135.6 LPM) forced through the working part of the mud hammer 100 and 700 GPM (2649.8 LPM) transported through the bypass pipe 104. This total transport flow rate is approximately 80% to 100% of the total well volume when drilling a 12.5-inch well to a depth of 5000 meters (16404 feet), and this flow capacity has been improved (e.g., 100% to 150%) relative to at least a portion of a typical fluid hammer or mud hammer as described above.

[0042] Therefore, mud hammers 100 and 200 receive a single-flow drilling fluid 14, deliver a measured amount of drilling fluid to the drill bit face 120, and process the remaining drilling fluid while limiting the negative effects of the drilling fluid on the internal components of the mud hammer. Compared to typical rotary mud drilling methods, the inventors have found that the mud hammer 100 drills at a faster rate in hard rock formations (e.g., 10 m / h or 32.81 ft / h compared to 300 mm / h or 0.98 ft / h). The inventors have also found that when drilling in hard rock formations, the mud hammer bit 108 has a longer service life than typical advanced rotary bits (e.g., 400 m or 1312.3 ft / h compared to 20 m or 65.62 ft / h at the end of its service life).

[0043] Figure 1 A cross-sectional view of a drilling system 10 according to an embodiment of the present invention is shown. The drilling system 10 includes a single-flow drill pipe 12 and a mud hammer 100. The single-flow drill pipe 12 can be any suitable, standard, and API-certified drill pipe. The single-flow drill pipe 12 can be coupled to the mud hammer 100. For example, the single-flow drill pipe 12 may include an external thread portion of an internal thread portion coupled to one end of the mud hammer 100. The flow 14 of drilling fluid can be delivered to the mud hammer 100 through the single-flow drill pipe 12. As those skilled in the art will recognize, drilling fluid includes drilling mud and various additives.

[0044] The main body of the mud hammer 100 may include multiple components. These components may include one or more of the following: piston cylinder 102, top sub-section 126, drive sub-section 138, and / or other suitable components, such as... Figure 2 The exploded view of the example mud hammer 200 shows one or more components. The mud hammer 100 includes a piston 106. The piston 106 is positioned within a piston cylinder 102. The piston 106 is configured to... Figure 1 The double arrow 128 indicates a reciprocating translational motion. The reciprocating motion of piston 106 defines the direction of the translation. Figure 1 The piston stroke length is specified by the double arrow 114. In various embodiments, the piston 106 can cycle back and forth at a rate of approximately 10 to 25 cycles per second as the fluid or mud pressure required for drilling operations is delivered to the mud hammer 100. One cycle is completed when the piston 106 returns to the starting position after translating two piston stroke lengths. In some embodiments, the piston 106 can be controlled to cycle at a rate lower than 10 to 25 cycles per second by reducing the pressure of the fluid or mud delivered to the mud hammer 100. Conversely, the piston's cycle speed can be increased by increasing the pressure of the fluid or mud delivered to the mud hammer 100. In some embodiments, the stroke length can be between approximately 20 and 60 mm (0.79 to 2.36 inches). In at least some examples, the piston stroke length can be approximately 40 mm (1.57 inches).

[0045] In some aspects, as piston 106 moves, interface 116 at one end of piston 106 impacts drill bit 108. In some examples, such as those shown, the other end of piston 106 impacts valve assembly 132. In other examples, valve assembly 132 may be positioned opposite one end of piston 106 as shown. In some embodiments, valve assembly 132 may be positioned around piston 106. As those skilled in the art will appreciate, valve assembly 132 is configured to cause movement of piston 106. In various instances, valve assembly 132 may include a single valve or may include multiple valves or other suitable components. In some instances, valve assembly 132 may include one or more check valves and / or plungers. In other aspects, piston 106 may include orifice 140, replacing or attached to valve assembly 132. Orifice 140 may be configured to cause movement of piston 106. Valve assembly 132 may be adjustable by having a variable orifice or diaphragm that controls the amount of drilling fluid that can flow through it. In some embodiments, valve assembly 132 is one of a plurality of valve assemblies 132 selected from a certain range of valve diameters.

[0046] In various aspects, the mud hammer 100 includes a wear-resistant bushing 134 positioned between the piston 106 and the piston cylinder 102. As the piston 106 moves in its reciprocating motion, friction between the piston 106 and the piston cylinder 102 can cause degradation of the piston 106 and / or the piston cylinder 102. Operating the mud hammer 100 with drilling fluid accelerates this degradation. To help prevent this degradation, the wear-resistant bushing 134 helps prevent contact between the piston 106 and the piston cylinder 102. As the piston 106 moves, the wear-resistant bushing 134 replaces the (more expensive) degradation of the piston 106 and / or the piston cylinder 102. The wear-resistant bushing 134 is made of a suitable wear-resistant material, such as tungsten, bialloy, carbon, and diamond-impregnated steel. The wear-resistant bushing 134 can be replaced when degradation reaches the wear limit at which the wear-resistant bushing 134 can no longer prevent contact between the piston 106 and the piston cylinder 102. In each instance, the wear-resistant bushing 134 is configured to have a service life approximately as long as that of the drill bit 108 during mud hammer 100 operations before the wear-resistant bushing 134 and the drill bit 108 reach their respective wear limits (e.g., approximately 40 hours of continuous operation).

[0047] In examples where the mud hammer 100 includes a valve assembly 132, the valve assembly 132 also moves in a reciprocating motion. In these examples, the mud hammer 100 may include a secondary wear-resistant bushing 136 located between the valve assembly 132 and the piston cylinder 102. To help prevent degradation of the valve assembly 132 and / or the piston cylinder 102, the wear-resistant bushing 136 helps prevent contact between the valve assembly 132 and the piston cylinder 102. The description of the wear-resistant bushing 134 applies equally to the secondary wear-resistant bushing 136. Therefore, taking into account the degradation-induced effects of operating the mud hammer 100 with drilling fluid, the wear-resistant bushings 134 and 136 extend the service life of the mud hammer 100.

[0048] In some aspects, the mud hammer 100 includes a bypass pipe 104. The bypass pipe 104 is positioned through the piston 106. In some instances, the bypass pipe 104 may be positioned through the valve assembly 132. In some instances, the bypass pipe 104 is centered relative to the piston 106 and / or piston cylinder 102 (e.g., positioned along its long axis). In some aspects, the inner diameter of the bypass pipe 104 is between approximately 2 inches and 3 inches (approximately 5.08 cm to 7.62 cm). The bypass pipe 104 is in fluid communication with the drill bit 108 (e.g., at interface 118), thereby allowing drilling fluid to be delivered to the drill bit 108 via the bypass pipe 104. The mud hammer 100 is configured such that a metered portion of the drilling fluid delivered to the mud hammer 100 is guided through the bypass pipe 104, while the remaining portion of the delivered drilling fluid is forced into the mud hammer 100 under pressure to operate the mud hammer 100. For example, starting from the mud fluid flow 14, a portion 16 of the flow 14 flows into the bypass pipe 104, while portions 18A and 18B flow into the mud hammer 100. Metering the amount of drilling fluid delivered to the drill face 120 through the bypass pipe 104 helps to avoid high-pressure cushion problems caused by excessive drilling fluid or mud being delivered to the drill face 120.

[0049] In various aspects, to control the metered flow into the bypass 104, the mud hammer 100 includes a valve assembly 130. The valve assembly 130 may be a single valve or an adapter, or it may be multiple valves and / or multiple adapters. In some instances, the valve assembly 130 may be a component of the bypass 104. In other instances, for example... Figure 1 and Figure 2 As shown, valve assembly 130 can be positioned at the receiving end of bypass 104. Valve assembly 130 can be configured to allow a set amount (e.g., flow 16) of drilling fluid 14 delivered to mud hammer 100 (e.g., flow 14) to flow into bypass 104. In some instances, this set amount can be less than 80% of the total delivered drilling fluid 14. In some instances, this set amount can be approximately 50% to 80% of the total delivered drilling fluid 14. In some aspects, valve assembly 130 can be non-adjustable, and thus configured to allow only a single set amount of drilling fluid into bypass 104. In other aspects, valve assembly 130 can be adjustable, so that the drilling operator can adjust the set amount of fluid configured to allow flow into bypass 104. Valve assembly 130 can be adjustable by having a variable orifice or diaphragm that controls the amount of drilling fluid that can flow through. In some embodiments, valve assembly 130 is one of a plurality of valve assemblies 130 selectable from a certain range of valve diameters. In these respects, adjustability provides the drilling operator with the ability to change the amount of drilling fluid 14 delivered to the drill face 120 based on different drilling conditions and geology.

[0050] The mud hammer 100 includes a drill bit 108. In some aspects, the drill bit 108 may be coupled to the body of the mud hammer 100, and therefore the drill bit is removable. The drill bit 108 includes a drill face 120. The drill bit 108 includes one or more outlets 122A, 122B, allowing drilling fluid 16 to be discharged from the drill face 120. The one or more outlets 122A, 122B are in fluid communication with a bypass pipe 104. The flow of drilling fluid 16 flows through the bypass pipe 104 and is discharged at the drill face 120 as one or more discharge flows 124A, 124B. During operation of the mud hammer 100, the one or more discharge flows 124A, 124B wash away drill cuttings from the drill bit 108.

[0051] In some aspects, the body of the mud hammer 100 may include a drive section, which includes a drive section 138 and a guard 226 (e.g., Figure 2 (As shown). In some aspects, the drive sub 138 includes a stabilizing fin. In some aspects, the drive sub may also include a suitable drill bit holding system for holding the drill bit 108.

[0052] The piston cylinder 102 of the mud hammer 100 includes one or more discharge ports 110A, 110B. These discharge ports 110A, 110B are located in... Figure 1 As shown in the diagram. However, it should be understood that in some embodiments, the piston cylinder 102 may include only a single outlet or two or more outlets. For embodiments with a single outlet, the outlet may extend around any suitable location around the piston cylinder 102. After the drilling fluid 18A, 18B flows through the valve assembly 132 and actuates the piston 106, the drilling fluid can be discharged from the piston cylinder 102 through one or more outlets 110A, 110B. The discharged drilling fluid from outlets 110A, 110B is discharged in a direction away from the drill bit 108 (e.g., upward during operation), as indicated by discharge flows 112A, 112B. Directing discharge flows 112A, 112B away from the drill bit 108 helps flush drill cuttings from the drill bit 108.

[0053] Figure 2 An exploded perspective view of a mud hammer 200 according to an embodiment of the present invention is shown. The mud hammer 200 is configured to operate as described above with respect to the mud hammer 100, wherein similar features are referred to by similar reference numerals. In various embodiments, the mud hammer 100 may include any component of the mud hammer 200, and vice versa. It should also be understood that... Figure 1 and Figure 2The components shown are not necessarily to scale. The mud hammer 200 may include a top sub 126. The mud hammer 200 includes a bypass pipe 104. A valve assembly 130 is positioned at the receiving end of the bypass pipe 104. In some instances, one or more O-rings 202 are positioned between the bypass pipe 104 and the valve assembly 130. The mud hammer 200 includes a piston 106. In some instances, the mud hammer 200 may include a wear-resistant bushing 134. The mud hammer 200 includes a piston cylinder 102. In some instances, the mud hammer 200 may include a drive sub 138. The mud hammer 200 includes a drill bit 108.

[0054] In various examples, the mud hammer 200 may include any suitable combination of the following components: one or more O-rings 204, a resilient retaining ring 206, a distributor 208, a top tube or sub 210, a check valve or plunger 211, a Y-ring or check valve 212, a spring 214, a compression damper 216, a bypass seat 218, a bearing bush 220, one or more drill bit stop rings 222, 224, and a guard 226. In some examples, the compression damper 216 may be a ring, for example, a steel ring. The check valve or plunger 211, the Y-ring or check valve 212, the spring 214, and / or the compression damper 216 may include a valve assembly 132. In some examples, the bearing bush 220 may be cold-pressed. In some examples, the drill bit stop ring 222 may be an O-ring. Figure 3 It shows Figure 2 The image shows an assembled perspective view of the mud hammer 200.

[0055] Figure 4 A flowchart illustrating a drilling method according to one aspect of this disclosure is shown. (Although references are provided...) Figure 4 The flowchart shown describes example method 400. It should be understood that many other methods can be used to perform the actions associated with method 400. For example, the order of some boxes can be changed, some boxes can be combined with other boxes, and some boxes are optional.

[0056] Mud hammers 100 and 200 can be positioned in the well (box 402). Mud hammers 100 and 200 can be any of the embodiments described herein. A single-flow drilling fluid 14 can be delivered to the mud hammers 100 and 200 via a single-flow drill pipe 12 (box 404). The drilling fluid 14 comprises drilling mud. The single-flow drill pipe 12 can be any suitable, standard, and API-certified drill pipe. In this example, the mud hammers 100 and 200 positioned in the well are configured to operate the drilling fluid such that a single flow 14 of the drilling fluid can be directed to the mud hammers 100 and 200. This contrasts with at least some typical DC fluid hammers, which require a dual-circulation drill pipe system to separate the drilling mud from the clean water. At least some of these typical DC fluid hammers cannot be operated via a single-flow drill pipe. Some typical DC fluid hammers can be adapted to operate through a single-flow drill pipe, but this adaptation results in mud hammers or fluid hammers that are less efficient than the mud hammers 100 and 200 described herein.

[0057] The mud hammers 100 and 200 can then be operated to drill in the well (box 406). In the example where the single-flow drilling fluid 14 is directed to the mud hammers 100 and 200, a set amount (e.g., between 50% and 80%) of the drilling fluid flows into the bypass pipe 104 of the mud hammers 100 and 200 during operation. In various instances, the drilling fluid 16 flowing into the bypass pipe 104 is discharged from the mud hammers 100 and 200 at the drill bit face 120. The remaining portions 18A and 18B of the single-flow drilling fluid 14 can flow into the mud hammers 100 and 200 outside the bypass pipe 104, thereby operating the mud hammers 100 and 200. In some aspects, method 400 may further include replacing one or more wear-resistant bushings (e.g., wear-resistant bushing 134 and / or wear-resistant bushing 136) of the mud hammers 100 and 200. In one example, the wear-resistant bushings 134 and / or 136 are replaced once they reach their respective wear limits. In another example, the wear-resistant bushings 134 and / or 136 are configured to reach their respective wear limits in the same time as the wear limits of the drill bit 108 during mud hammer 100, 200 operations.

[0058] As used herein, “approximately,” “generally,” and “basically” are understood to mean a number within a range of values, such as referring to the range of -10% to +10%, preferably referring to the range of -5% to +5%, more preferably referring to the range of -1% to +1%, and most preferably referring to the range of -0.1% to +0.1%.

[0059] The terms “comprising,” “including,” or “having” used in this specification and claims are used in an inclusive sense, indicating the presence of the stated features but not excluding the presence of additional or other features.

[0060] Furthermore, all numerical ranges herein should be understood to include all numbers within that range, whether integers or fractions. These numerical ranges should be interpreted as supporting claims that refer to any number or subset of numbers within that range. For example, disclosures of 1 to 10 should be interpreted as supporting ranges of 1 to 8, 3 to 7, 1 to 9, 3.6 to 4.6, 3.5 to 9.9, and so on.

[0061] The examples and aspects disclosed herein are to be interpreted as illustrative only and are not intended to limit the scope of this disclosure in any way. It will be apparent to those skilled in the art that modifications can be made to the details of the foregoing examples without departing from the fundamental principles discussed. In other words, various modifications and improvements to the examples specifically disclosed above are within the scope of the appended claims. For example, any suitable combination of features from the various examples may be considered.

Claims

1. A mud hammer, comprising: A piston cylinder configured to receive a single-flow drilling fluid comprising drilling mud, the piston cylinder including at least one outlet for discharging the drilling fluid to the outside of the mud hammer; A piston, which is positioned inside the piston cylinder and configured to be moved by a first portion of the drilling fluid in a reciprocating motion; A bypass pipe, which passes through the piston and is in fluid communication with the drill bit; An adjustable valve assembly configured to divert a second portion of the drilling fluid into the bypass pipe; The wear-resistant bushing is positioned to prevent contact between the piston and the piston cylinder; A second portion of the drilling fluid diverted to the bypass pipe is discharged from the drill bit, while a first portion of the drilling fluid operating the piston is discharged from the piston cylinder through the at least one outlet, away from the drill bit.

2. The mud hammer according to claim 1, wherein the wear-resistant bushing is made of wear-resistant material.

3. The mud hammer according to claim 2, wherein the wear-resistant material is at least one of tungsten, bialloy, carbon, and diamond-impregnated steel.

4. The mud hammer according to any one of claims 1-3, wherein the adjustable valve assembly is located at the receiving end of the bypass pipe.

5. The mud hammer according to claim 1, wherein the adjustable valve assembly is a component of the bypass pipe.

6. The mud hammer of claim 1, further comprising a secondary valve assembly configured to guide the drilling fluid of the first portion to induce the reciprocating motion of the piston.

7. The mud hammer of claim 6, wherein the bypass pipe is positioned through the secondary valve assembly.

8. The mud hammer according to claim 6 or claim 7, further comprising an anti-wear secondary bushing positioned to prevent contact between the secondary valve assembly and the piston cylinder.

9. The mud hammer of claim 1, wherein the inner diameter of the bypass pipe is between 2 and 3 inches.

10. The mud hammer according to claim 1, wherein the bypass pipe is located at the center of the piston cylinder.

11. The mud hammer of claim 1, further comprising a drive sub, the drive sub having at least one of the following: a stabilizing wing, a shield, and a drill bit holding system.

12. The mud hammer of claim 1, wherein the piston cylinder includes at least two outlets configured to discharge drilling fluid upwards away from the drill bit during use.

13. The mud hammer according to claim 1, wherein the drill bit is an impact drill bit.

14. The mud hammer according to claim 1, wherein the stroke length of the piston is between 20 mm and 60 mm.

15. The mud hammer of claim 1, wherein the piston circulates at a rate of 10 to 25 cycles per second.

16. The mud hammer of claim 1, wherein the mud hammer is in fluid communication with a single-flow drill pipe for delivering single-flow drilling fluid to a piston cylinder, wherein the single-flow drill pipe includes an internal blowout preventer.

17. A drilling system, comprising: A single-flow drill pipe is constructed to transport a single flow of drilling fluid, including drilling mud. A mud hammer in fluid communication with the single-flow drill pipe, the mud hammer comprising: A piston cylinder, comprising at least one outlet for discharging drilling fluid to the outside of the mud hammer; A piston, which is positioned inside the piston cylinder and configured to be moved by a first portion of the drilling fluid in a reciprocating motion; A bypass pipe passes through the piston and is in fluid communication with the drill bit; An adjustable valve assembly configured to divert a second portion of the drilling fluid into the bypass pipe; The wear-resistant bushing is positioned to prevent contact between the piston and the piston cylinder; The second portion of the drilling fluid diverted to the bypass pipe is discharged from the drill bit, while the first portion of the drilling fluid that operates the piston is discharged from the piston cylinder through the outlet, away from the drill bit.

18. The drilling system of claim 17, wherein the stroke length of the piston is between 20 mm and 60 mm.

19. The drilling system of claim 17 or claim 18, wherein the piston circulates at a rate of 10 to 25 cycles per second.

20. The drilling system of claim 17, wherein the single-flow drill pipe includes an internal blowout preventer.

21. A drilling method, comprising: (a) Positioning a mud hammer in the wellbore, the mud hammer comprising: A piston cylinder, comprising at least one outlet configured to discharge drilling fluid to the outside of the mud hammer; A piston, which is positioned inside the piston cylinder and configured to be moved by a first portion of the drilling fluid in a reciprocating motion; A bypass pipe that passes through the piston, is positioned, and is in fluid communication with the impact drill bit, which has a drill bit face; An adjustable valve assembly configured to divert a second portion of the drilling fluid into the bypass pipe; The wear-resistant bushing is positioned to prevent contact between the piston and the piston cylinder; (b) The drilling fluid, comprising drilling mud, is directed through a single-flow drill pipe to the mud hammer. (c) Operating the mud hammer to drill in the well; A second portion of the drilling fluid diverted to the bypass pipe is discharged from the drill bit at the drill bit face, while a first portion of the drilling fluid operating the piston is discharged from the piston cylinder through the at least one outlet, away from the drill bit.

22. The drilling method of claim 21, wherein the second portion of the drilling mud accounts for between 50% and 80% of the total drilling fluid delivered to the mud hammer.

23. The drilling method according to claim 21 or claim 22, wherein the drilling fluid is delivered to the mud hammer under pressure.

24. The drilling method of claim 21, wherein the single-flow drilling fluid is directed to the mud hammer at a rate of 800 gallons per minute to 1000 gallons per minute.

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