Bit insert temperature control structure and welding method

Abstract

The present application relates to a kind of drill bit leg control temperature structure and welding method, it includes: drill bit body;Rolling cutting assembly, it is fixed on the drill bit body, the rolling cutting assembly includes leg and is installed on the leg shaft bit cone;Cooling block, it is installed on the leg, and one side is consistent with the leg, the cooling block is connected with cooling pipeline;Thermocouple, it is installed on the cooling block, the thermocouple passes through the assembly block and is contacted with the leg.By using low heat input welding technology and cooperating with the welding layer arrangement mode of specific U-shaped weld, the whole drill bit group welding is completed, the temperature control of leg shaft is realized by cooling device and air cooling device cooling system, temperature monitoring, through real-time temperature monitoring and control to leg, the temperature near leg can be reasonably controlled, avoid the failure of sealing rubber ring installed on leg shaft due to the temperature of leg shaft is too high, avoid the generation of welding crack, so as to realize drill bit group welding automation.

Description

Technical Field

[0001] This invention relates to the field of welding technology, and in particular to a temperature control structure for drill bits and a welding method thereon. Background Technology

[0002] Drill bit assembly welding refers to the welding of the rolling cutting assembly to a specific part of the rolling cutting assembly or the welding of the rolling cutting assembly to the drill bit body. The rolling cutting assembly includes the die and the die mounted on the die shaft. During operation, the die rotates around the die shaft. To prevent bearing lubricating oil leakage and foreign matter from entering the die shaft, a sealing ring is required to seal the die shaft. The sealing ring used for assembling the die and die shaft is generally made of rubber, with a temperature resistance not exceeding 170℃. Since the assembly process of the die and die shaft must be completed before welding, the heat generated during the pre-welding heat treatment and welding process will raise the temperature of the die shaft, adversely affecting the sealing ring. To avoid the heat from the welding process affecting the performance of the sealing ring, the temperature of the die shaft in close contact with the sealing ring must be controlled.

[0003] To avoid welding cracks, the drill bit body needs to be preheated before welding. However, the temperature of the tooth bearing shaft must be controlled throughout the welding process, creating a contradiction between the two technical requirements. In related technologies, to resolve this contradiction, the method for controlling the tooth bearing shaft temperature during drill bit assembly welding is as follows: after preheating each drill bit body and completing two or three welds, welding is stopped. The drill bit is then placed in a circulating water tank for cooling. Once cooled to a certain temperature, the drill bit body is preheated again and welding continues, repeating this cycle until the entire drill bit welding is completed.

[0004] However, the temperature control method of the tooth shaft in this welding process makes it difficult to automate the drill bit assembly welding process. It can only be done by manual welding, which has low processing efficiency and high processing cost. Furthermore, improper operation during repeated preheating, welding and cooling processes can easily cause welding cracks, affecting the service life of the drill bit. Summary of the Invention

[0005] This invention provides a drill bit temperature control structure and welding method to solve the problems of difficult automation, low processing efficiency, high processing cost, and easy welding cracks in related technologies.

[0006] In a first aspect, a drill bit tooth control temperature control structure is provided, comprising: a drill bit body; a rolling cutting assembly fixed to the drill bit body, the rolling cutting assembly including a tooth plate and a toothed wheel mounted on the tooth plate shaft; a cooling block mounted on the tooth plate, one side of which is in contact with the tooth plate, the cooling block being connected to a cooling pipe; and a thermocouple passing through the assembly block and in contact with the tooth plate.

[0007] In some embodiments, the contact surface of the cooling block on the side near the palm has a shape that matches the palm.

[0008] In some embodiments, the contact surface is coated with a thermal interface material.

[0009] In some embodiments, the cooling block has mounting blocks on opposite sides extending toward the tooth, through which the thermocouple contacts the tooth.

[0010] In some embodiments, the thermocouple is connected to a spring that presses the thermocouple against the tooth.

[0011] In some embodiments, a gas turbine cooling pipe is provided near the tooth bearing shaft of the toothed wheel.

[0012] In some embodiments, a heat sink is installed on the inner side of the palm.

[0013] In some embodiments, the surface of the air-cooled heat sink is provided with a grid.

[0014] In some embodiments, the cooling block is provided with multiple mounting slots, and magnets are installed in the mounting slots.

[0015] Secondly, a welding method for a temperature-controlled structure using drill bit teeth is provided, comprising the following steps: welding the first layer of a first U-shaped weld on the drill bit; rotating to a second U-shaped weld and welding the first layer of the second U-shaped weld, repeating the above steps until the first layer of the U-shaped welds on the entire drill bit body is welded; welding the second layer of the first U-shaped weld, repeating the welding method of the first layer of the U-shaped welds, until the U-shaped welds on the entire drill bit are welded.

[0016] In some embodiments, the U-shaped weld is welded using cold metal transfer technology or low heat input welding technology.

[0017] The beneficial effects of the technical solution provided by this invention include: This invention provides a temperature control structure and welding method for drill bit teeth. By real-time temperature monitoring and control of the teeth, the temperature near the teeth can be reasonably controlled, avoiding the generation of welding cracks, improving the service life of the drill bit, solving the temperature control problem of drill bit assembly welding, thereby realizing the automation of drill bit assembly welding, improving welding efficiency, and reducing production costs. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the overall structure of the drill bit temperature control structure provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the overall structure of the drill bit temperature control structure provided in an embodiment of the present invention from another angle.

[0020] Figure 3 A schematic diagram of the cooling block of the drill bit temperature control structure provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the air-cooled heat sink of the drill bit temperature control structure provided in an embodiment of the present invention.

[0021] Numbering on the map: 1. Drill body; 2. U-shaped weld; 3. Tooth bearing; 4. Tooth bearing shaft; 5. Cooling block; 6. Cooling pipe; 7. Gas turbine air-cooled pipe; 8. Tooth cone; 9. Thermal interface material; 10. Thermocouple; 11. Contact surface; 12. Air-cooled heat sink; 13. Assembly block; 14. Mounting slot. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] This invention provides a drill bit temperature control structure and welding method, which can solve the problems of difficult automation, low processing efficiency, high processing cost, and easy welding cracks in related technologies.

[0024] See Figure 1 and Figure 2As shown, an embodiment of the present invention provides a drill bit gear control temperature control structure, which includes: a drill bit body 1; a rolling cutting assembly fixed to the drill bit body 1, the rolling cutting assembly including a gear 3 and a gear 8 mounted on a gear shaft 4; a cooling block 5 mounted on the gear 3, with one side in contact with the gear 3, the cooling block 5 being connected to a cooling pipe 6; and a thermocouple 10 passing through the assembly block 13 and contacting the gear 3. In this embodiment, the cooling block 5 has a fluid channel inside and is connected to the cooling pipe 6 outside. The cooling pipe 6 is connected to external coolant and cooling water. The coolant can be industrial water or cooling water, and the water flow rate of the cooling pipe is not less than [amount missing]. With a flow rate of 0.15 L / min, the cooling block 5 is made of materials with high thermal conductivity, such as copper or aluminum alloy, with a thermal conductivity ranging from 30 to 500 W / (m·K). The cooling block 5 monitors and controls the temperature of the toothed shaft 3 in real time, which can reasonably control the temperature near the toothed shaft 3, avoid the generation of welding cracks, and improve the service life of the drill bit. It solves the problem of temperature control in drill bit assembly welding, improves welding efficiency, and reduces production costs. It provides a "cooling-while-welding" welding technology for toothed shaft temperature control in drill bit automated production. With the help of customized automatic welding equipment and its welding program, the temperature of the toothed shaft 4 is controlled to not exceed 130℃ during the preheating before assembly welding and during the welding process, realizing automated welding of drill bit assembly.

[0025] The welding process includes: a) fixing the drill body 1 and the toothed shaft 3 in place; b) starting temperature monitoring and cooling of the area near the toothed shaft 4; c) preheating the drill body 1 to above 250°C; d) performing U-shaped weld 2 welding.

[0026] See Figure 3 As shown, in some embodiments, the contact surface 11 of the cooling block 5 on the side near the toothed palm 3 has a shape that matches the toothed palm 3. The contact surface 11 with the toothed palm 3 is designed to increase the contact area with the toothed palm 3 and there is sufficient space to avoid welding in the weld area of ​​the toothed palm 3.

[0027] See Figure 3 As shown, in some embodiments, the contact surface 11 is covered with a thermal interface material 9. The thermal interface material 9 is located at the contact surface between the cooling block 5 and the tooth 3. The thermal interface material 9 forms an integral component with the cooling block 5 by assembly or bonding. The thermal interface material 9 fills the gap between the contact surface between the cooling block 5 and the tooth 3, and reduces the contact thermal resistance between the tooth 3 and the cooling block 5. The thermal interface material 9 is made of a flexible thermally conductive material, such as a flexible graphite pad, thermally conductive silicone, or thermally conductive putty, with a thermal conductivity of 2-200 W / (m·K).

[0028] See Figure 3As shown, in some embodiments, the cooling block 5 has mounting blocks 13 extending toward the toothed palm 3 on opposite sides. The thermocouple 10 passes through the mounting block 13 and contacts the toothed palm 3. The thermocouple 10 for temperature measurement contacts the toothed palm 3 through the mounting hole on the mounting block 13. The measurement point is the surface of the toothed palm 3 closer to the toothed palm shaft 4 or the monitoring hole. The temperature near the toothed palm shaft 4 is monitored by the thermocouple 10 to determine whether the toothed palm shaft 4 is overheated. Based on this, the flow rate of the coolant in the cooling pipe is adjusted to control the cooling effect.

[0029] See Figure 3 As shown, in some embodiments, the thermocouple 10 is connected to a spring to press the thermocouple 10 onto the tooth 3. The thermocouple 10 can achieve close contact and separation between the thermocouple monitoring end and the surface of the tooth 3 through the spring structure, or other methods can be used.

[0030] See Figure 1 As shown, in some embodiments, a gas turbine cooling pipe 7 is provided near the tooth bearing 4 of the tooth wheel 8. By placing a gas turbine cooling pipe 7 near the tooth bearing 4 of the tooth wheel 8, the gas turbine cooling pipe 7 is filled with cooling air, and the air outlet provides air cooling to the inner side of the tooth bearing 3, thereby achieving a better cooling effect on the tooth bearing 4.

[0031] See Figure 4 As shown, in some embodiments, a wind-cooled heat sink 12 is installed on the inner side of the toothed palm 3. The wind-cooled heat sink 12 is made of copper and can conduct heat away from the contact position with the inner side of the toothed palm 3. The wind-cooled heat sink 12 and the gas turbine air-cooling pipe 7 can supplement the cooling block 5 to control the temperature of the toothed palm shaft 4, or they can be used alone. The air outlet position avoids the U-shaped weld seam 2 area and does not affect the quality of the weld seam.

[0032] See Figure 4 As shown, in some embodiments, the surface of the air-cooled heat sink 12 is provided with a grid. By providing a grid structure on the surface of the air-cooled heat sink 12, the contact area between the air-cooled heat sink 12 and the cold air can be increased, thereby accelerating the heat dissipation of the area.

[0033] See Figure 3 As shown, in some embodiments, the cooling block 5 is provided with a plurality of mounting slots 14, and magnets are installed in the mounting slots 14. The cooling block 5 can be installed on the toothed palm 3 by means of magnets, which is convenient for installation and facilitates control of the contact and separation between the cooling block 5 and the cooling surface of the toothed palm 3.

[0034] See Figure 1As shown, in some embodiments, the cooling block 5 is detachably installed on the toothed plate 3. The cooling block 5 can be fixed on the drill bit welding station or used independently. The contact and separation between the cooling block 5 and the cooling surface of the toothed plate can be controlled automatically or manually.

[0035] In this embodiment of the invention, the welding method of the U-shaped weld 2 of the drill bit is as follows: after welding the first U-shaped weld on the drill bit, rotate to the second U-shaped weld to weld the first layer, until the first layer of the U-shaped weld on the entire drill bit body is completed, and then start welding the second layer of the first U-shaped weld. Repeat the welding method of the first layer of the U-shaped weld until the welding of the U-shaped weld 2 on the entire drill bit is completed.

[0036] Case 1: For small-sized drilling bits (≤8 1 / 2), the tooth shaft 4 heats up quickly during preheating and welding, making temperature control difficult. Therefore, a cooling system combining air and water cooling is adopted. The specific implementation steps are as follows: Step 1: At the welding station, use gas metal arc welding to spot weld and fix the drill body 1 and the tooth plate at the weld joint.

[0037] Step 2: Place the cooling block 5 tightly against the cooling surface of the toothed joint 3. The cooling block 5 is made of copper or aluminum alloy. A layer of thermal interface material is applied at the bonding point between the cooling block 5 and the toothed joint 3 to reduce the contact thermal resistance between them. The interface material is thermally conductive putty, which effectively fills the gap between the toothed joint and the cooling block 5. The thermal conductivity is 1–8 W / (m·K), and the thickness is 1–5 mm. The cooling block 5 has internal fluid channels, and the cooling liquid can be industrial water or cooling water. The water flow rate of the cooling block 5 is controlled by a water pump between 0.5 and 5 L / s. A temperature sensor is pressed against the surface of the toothed joint 3 using a spring mechanism to ensure real-time monitoring of the temperature near the toothed joint shaft 4 during welding.

[0038] Step 3: Before preheating, turn on cooling pipe 6 to control the temperature of the drill bit 3. The coolant temperature in cooling pipe 6 is 0℃~80℃. The preheating method for the welding part is to preheat the drill bit body 1 with an oxy-acetylene flame to a preheating temperature above 250℃. During the preheating process, thermocouple 10 monitors the temperature at the monitoring point. When the temperature at the monitoring point exceeds the temperature control range, the water flow rate in cooling pipe 6 is increased to control the temperature near the drill bit shaft 4 to below 130℃.

[0039] Step 4: Place a gas turbine cooling pipe 7 near the tooth bearing 4 on the gear 8. The turbine pipe has compressed air at the input and cooling air at the output. The cold air from the outlet blows onto the heat sink fixed inside the gear 8 without affecting the weld quality. The compressed air pressure is 0.7MPa~5MPa, the gas flow rate is 223L / min~1130L / min, and the cooling capacity is 131kcal / h~706kcal / h.

[0040] Step 5: Perform assembly welding using Cold Metal Transfer (CMT) or other low heat input techniques. The welding steps are as follows: weld one layer of the first U-shaped weld on the drill body 1, then rotate to the second U-shaped weld and continue welding until the first layer of all U-shaped welds is completed before starting the second layer. Repeat this process until the entire drill bit welding is complete. During the welding process, thermocouple 10 monitors the temperature at the monitoring location. If the temperature at the monitoring point exceeds the temperature control range, increase the water flow in the cooling pipe 6 to control the temperature near the toothed shaft 4 below 130℃.

[0041] Step 6: After welding, wait 2-10 minutes for the temperature near the tooth palm shaft 4 to cool down to below 130℃, and then rotate it to other workstations.

[0042] Case 2: For large-size drilling bits (>8 1 / 2), the tooth shaft 4 uses water cooling for temperature control and welding cooling. The specific implementation steps are as follows: Step 1: At the welding station, use gas metal arc welding to spot weld and fix the drill body 1 and the toothed part 3 at the weld joint.

[0043] Step Two: Place the cooling block 5 tightly against the cooling surface of the toothed joint 3. In this technology, the cooling block 5 is made of copper or aluminum alloy. A thermal interface material is applied at the bonding point between the cooling block 5 and the toothed joint 3 to reduce the contact thermal resistance between them. The interface material is a flexible graphite pad that effectively fills the gap between the toothed joint 3 and the cooling block 5, with a thermal conductivity of 150 W / (m·K) and a thickness of 1–3 mm. The cooling block 5 has internal fluid channels, and the cooling liquid can be industrial water or cooling water. The water flow rate of the cooling block 5 is controlled by a water pump between 0.5 and 5 L / min. A temperature sensor is pressed against the surface of the toothed joint 3 using a spring mechanism, ensuring close contact and real-time monitoring of the temperature near the toothed joint shaft 4 during welding.

[0044] Step 3: Before preheating, turn on cooling pipe 6 to control the temperature of the drill bit. The coolant temperature in cooling pipe 6 is 0℃-80℃. The preheating method for the welding part is to preheat the drill bit body 1 with an oxy-acetylene flame to a preheating temperature above 250℃. During the preheating process, thermocouple 10 monitors the temperature at the monitoring point. When the temperature at the monitoring point exceeds the temperature control range, the water flow rate in cooling pipe 6 is increased to control the temperature near the drill bit shaft 4 below 130℃.

[0045] Step 4: Perform assembly welding using Cold Metal Transfer (CMT) or other low heat input techniques. The welding steps are as follows: weld one layer of the first U-shaped weld on the drill body 1, then rotate to the second U-shaped weld and continue welding until the first layer of all U-shaped welds is completed before starting the second layer. Repeat this process until the entire drill bit welding is complete. During the welding process, thermocouple 10 monitors the temperature at the monitoring location. If the temperature at the monitoring point exceeds the temperature control range, increase the water flow in the cooling pipe 6 to control the temperature near the toothed shaft 4 below 130℃.

[0046] Step 5: After welding, wait 2-10 minutes for the temperature near the tooth palm shaft 4 to cool down to below 130℃, and then rotate it to other workstations.

[0047] The principle of the drill bit temperature control structure provided in this embodiment of the invention is as follows: The entire drill bit assembly is completed by employing low-heat-input welding technology and a specific U-shaped weld layer arrangement. A cooling system consisting of a cooling device and an air-cooling device, along with temperature monitoring, controls the temperature of the tooth bearing 4. This effectively controls the temperature near the tooth bearing 3, preventing welding cracks and extending the drill bit's lifespan. It also prevents the high temperatures during the drill bit assembly welding process from damaging the tooth bearing 4 seal, reducing the risk of seal failure. This solves the temperature control problem in drill bit assembly welding, avoiding repeated preheating, welding, and cooling processes. As a result, drill bit assembly welding is automated, welding efficiency is improved, production costs are reduced, and the drill bit assembly welding qualification rate is increased.

[0048] In the description of this invention, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0049] It should be noted that in this invention, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0050] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A temperature controlled bit gage, comprising: It includes: Drill body (1); A rolling cutting assembly is fixed to the drill body (1), the rolling cutting assembly including a toothed plate (3) and a toothed wheel (8) mounted on the toothed plate shaft (4). Cooling block (5) is installed on the toothed palm (3) and one side is in contact with the toothed palm (3). Cooling block (5) is connected to cooling pipe (6). Thermocouple (10) is mounted on the cooling block (5) and the thermocouple (10) is in contact with the tooth (3); The cooling block (5) has mounting blocks (13) on opposite sides extending toward the toothed palm (3), and the thermocouple (10) passes through the mounting blocks (13) and contacts the toothed palm (3). The thermocouple (10) is connected to a spring, which presses the thermocouple (10) onto the tooth (3); A thermal interface material (9) is provided between the contact surface (11) of the cooling block (5) near the tooth (3) and the contact surface of the tooth (3); the thermal interface material (9) is an elastic thermally conductive material. The cooling block (5) is made of copper or aluminum alloy with a thermal conductivity of 30 to 500 W / (m·K); the cooling block (5) is provided with multiple mounting slots (14), and magnets are installed in the mounting slots (14); the cooling block (5) is installed on the tooth palm (3) by magnets. For small-diameter drilling bits with a diameter less than or equal to 8 1 / 2, the thermal interface material (9) is made of thermally conductive mud with a thermal conductivity of 1-8 W / (m·K) and a thickness of 1-5 mm. Before preheating, the cooling pipe (6) is opened to control the temperature of the toothed part (3). The temperature of the coolant in the cooling pipe (6) is 0℃-80℃. The preheating method for the welding part is to preheat the drill bit body (1) with an oxyacetylene flame. The preheating temperature is above 250℃. During the preheating process, the thermocouple (10) monitors the temperature at the monitoring position. When the temperature at the monitoring point exceeds the temperature control range, the thermocouple (10) is increased. The water flow rate in the cooling pipe (6) controls the temperature near the tooth shaft (4) to be below 130°C; the toothed wheel (8) is provided with a gas turbine air-cooling pipe (7) near the tooth shaft (4); the tooth (3) is equipped with an air-cooled heat sink (12) on the inner side; the gas turbine air-cooling pipe (7) has compressed air at the input end and cooling air at the output end; the compressed air pressure is 0.7MPa~5MPa; the gas flow rate is 223L / min~1130L / min; and the cooling capacity is 131kcal / h~706kcal / h. For large-diameter drilling bits with a diameter greater than 8 1 / 2, the thermal interface material (9) is a flexible graphite pad with a thermal conductivity of 150 W / (m·K) and a thickness of 1 to 3 mm. Before preheating, the cooling pipe (6) is turned on to control the temperature of the toothed part (3). The temperature of the coolant in the cooling pipe (6) is 0℃ to 80℃. The preheating method of the welding part is to preheat the drill bit body (1) with an oxyacetylene flame. The preheating temperature is above 250℃. During the preheating process, the thermocouple (10) monitors the temperature at the monitoring position. When the temperature at the monitoring point exceeds the temperature control range, the water flow rate in the cooling pipe (6) is increased to control the temperature near the toothed part shaft (4) to be below 130℃. A weld seam is provided between the drill bit body (1) and the toothed part (3), and the weld seam is a U-shaped weld seam (2). The welding method of the U-shaped weld (2) is: welding the first layer of the first U-shaped weld (2) on the drill bit body (1); Rotate to the second U-shaped weld (2), weld the first layer of the second U-shaped weld (2), and repeat the above steps until the first layer of the U-shaped weld (2) of the entire drill bit body is welded; Repeat the welding method of the first layer of the U-shaped weld (2) to weld the remaining layers of the U-shaped weld (2) until the welding of the U-shaped weld (2) on the entire drill bit is completed.

2. The drill bit temperature control structure as described in claim 1, characterized in that: The contact surface (11) of the cooling block (5) on the side near the tooth (3) has a shape that matches the tooth (3).

3. The drill bit temperature control structure as described in claim 1, characterized in that: The surface of the air-cooled heat sink (12) is provided with a grid.

4. A welding method utilizing the drill bit temperature control structure as described in claim 1, characterized in that: The U-shaped weld (2) is welded using cold metal transfer technology or low heat input welding technology.

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