Intelligent laser cladding welding device and process capable of dynamically adjusting powder feeding rate

Abstract

The invention discloses an intelligent laser cladding welding device capable of dynamically adjusting the powder feeding rate, which comprises a laser collimator, a welding main body is mounted on the lower end surface of the laser collimator, and a laser channel pipe is coaxially arranged in the welding main body; an annular powder cavity is formed between the laser channel pipe and the welding body, one side of the welding body is connected with a powder feeding pipe, the powder feeding pipe is communicated with the annular powder cavity, and the powder feeding pipe is externally connected with a powder feeder. A welding head is arranged below the welding main body; a powder discharging mechanism is arranged on the outer side wall of the welding body and communicates with the annular powder cavity.

Description

Technical Field

[0001] The present invention belongs to the technical field of laser welding, and in particular relates to an intelligent laser cladding welding device and process for dynamically adjusting the powder feeding rate. Background Art

[0002] In traditional laser cladding welding technology, metal powder needs to be sprayed according to a specified powder feeding amount, and the powder feeding rate can be changed by adjusting the power of the powder feeder; however, the inventors found during use that the powder feeder's dynamic adjustment of the powder feeding rate has a slow response speed and a response delay, which makes it easy for the metal powder to be excessive or insufficient and unable to match the actual changes in the molten pool; and the powder feeding rate of most powder feeders is prone to deviate from the expected value during adjustment and use, and to cause powder blockage to a certain extent (which is more frequent when the powder feeding rate is reduced). Frequent adjustment of the powder feeder speed will also cause discontinuous powder flow, leading to problems such as uneven cladding layer and porosity. Summary of the Invention

[0003] To achieve the above-mentioned object, the present invention provides the following technical solution: an intelligent laser cladding welding device with dynamically adjustable powder feeding rate, comprising a laser collimator, a welding body being mounted on the lower end surface thereof, and a laser channel tube being coaxially arranged in the welding body;

[0004] An annular powder cavity is provided between the laser channel tube and the welding body, and a powder feeding pipe is connected to one side of the welding body, the powder feeding pipe is connected to the annular powder cavity, and a powder feeder is externally connected to the powder feeding pipe;

[0005] A welding head is provided below the welding body;

[0006] The outer side wall of the welding body is provided with a powder discharge mechanism, and the powder discharge mechanism is connected with the annular powder chamber.

[0007] Furthermore, preferably, a straight pipe is vertically connected to the outside of the annular powder chamber, one end of the powder feeding pipe is connected to the straight pipe, a conduit is coaxially arranged in the straight pipe, and a plurality of ribs are obliquely distributed in the conduit.

[0008] Furthermore, preferably, a plurality of ultrasonic transducers are provided on the inner wall of the straight-through tube, and the ultrasonic transducers are connected to the catheter.

[0009] Furthermore, preferably, spiral streamlines are distributed circumferentially on the outer wall of the laser channel tube, and an air inlet is provided on the side wall of the welding body near the upper end of the laser channel tube.

[0010] Further, as a preference, the powder discharge mechanism includes a powder discharge pipe connected to the outside of the welding body, a plurality of axially distributed inner channels are opened on the inner circumference of the welding body, and an annular bin is opened on the inner wall of the welding body, the upper end of each inner channel is connected to the annular bin, and the powder discharge pipe is connected to the annular bin;

[0011] A plurality of guide holes corresponding to the inner channel are further provided in the side wall of the welding body, and the guide holes are connected to the inner channel.

[0012] Furthermore, preferably, each of the guide holes extends tangentially along the circumference of the annular powder chamber, and the extending direction of the guide holes is opposite to the direction of the spiral streamline.

[0013] Furthermore, preferably, a cut-off sleeve is provided in each of the guide holes, a valve core is provided in the cut-off sleeve, and one end of the valve core is connected to a support spring.

[0014] Furthermore, preferably, a powder feeding nozzle is slidably installed inside the welding head, and an inner spring is provided on the outer sleeve of the powder feeding nozzle; a vibrator is installed on one side of the welding head, and the output end of the vibrator is rotatably connected to a shaft, and the other end of the shaft is connected to the powder feeding nozzle.

[0015] Furthermore, preferably, the powder spraying port of the powder feeding nozzle is configured as a conical structure.

[0016] The intelligent laser cladding welding process with dynamically adjusted powder feeding rate includes the following steps:

[0017] Step 1: Before laser welding, select metal powder that matches the workpiece, ensure that the dryness, fluidity, and particle size distribution meet the requirements, and load the powder into the powder feeder; set the working power of the laser welder and the powder feeder's powder feed rate so that the powder feed rate reaches the maximum set value for the powder feed required for laser cladding;

[0018] Step 2: Start the welding operation. The welding body is laser clad along the predetermined trajectory. The powder feeder sends the metal powder airflow into the conduit of the straight-through pipe. The conduit can generate radial high-frequency vibration under the vibration of the ultrasonic transducer. The metal powder flows through the internal ribs in the conduit and is fully dispersed.

[0019] Step 3: After entering the annular powder chamber, the metal powder flows vertically downward. At the same time, the air inlet guides auxiliary air into the annular powder chamber, causing the metal powder to generate a spiral flow along the spiral streamline in the annular powder chamber. At the same time, the powder discharge pipe in the powder discharge mechanism provides negative pressure suction to suck out a portion of the metal powder, reducing the amount of powder fed into the welding head, so that the actual amount of metal powder ejected from the welding head just meets the expected standard for welding cladding.

[0020] Step 4: The vibrator adjusts the powder feeding nozzle axially based on the actual amount of metal powder ejected from the welding head, thereby changing the size of its internal flow gap, and provides vibration powder discharge based on the dryness and particle size of the metal powder.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] During the laser cladding welding operation in the present invention, the powder discharge mechanism can be set to the maximum powder feeding rate according to the powder feeding amount required for laser cladding, so as to ensure that the amount of metal powder meets the welding requirements during the welding process. The powder discharge mechanism mainly arranged therein can perform negative pressure suction on the metal powder in the annular powder chamber through multiple guide holes to change the powder feeding amount, thereby eliminating the need to adjust the power of the powder feeder, avoiding frequent speed changes of the powder feeder causing powder pulsation or blockage, and shortening the response delay, thereby matching the rapid changes in the molten pool state. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0024] Figure 2 Schematic diagram of the internal structure of the straight-through pipe in the present invention;

[0025] Figure 3 is a cross-sectional view of the channel within the row of the present invention;

[0026] Figure 4 Schematic diagram of the cross-sectional structure of the laser channel tube in the present invention;

[0027] Figure 5 is a schematic cross-sectional view of the guide hole in the present invention;

[0028] Figure 6 Schematic diagram of the structure of the intercepting sleeve in the present invention;

[0029] Figure 7 Schematic diagram of the internal structure of the welding head in the present invention;

[0030] In the figure: 1. Welding body; 11. Laser collimator; 12. Laser channel tube; 13. Annular powder chamber; 14. Air inlet; 2. Powder feeding pipe; 21. Straight pipe; 22. Conduit; 23. Ultrasonic transducer; 24. Rib; 3. Powder discharge mechanism; 31. Powder discharge pipe; 32. Inner channel; 33. Annular bin; 34. Guide hole; 35. Shut-off sleeve; 36. Valve core; 4. Welding head; 41. Powder feeding nozzle; 42. Inner spring; 43. Vibrator; 44. Shaft. DETAILED DESCRIPTION

[0031] See also Figure 1-Figure 7In an embodiment of the present invention, an intelligent laser cladding welding device with a dynamically adjustable powder feeding rate includes a laser collimator 11, a welding body 1 is mounted on the lower end surface of the laser collimator, and a laser channel tube 12 is coaxially arranged in the welding body 1 for the laser beam to pass through;

[0032] An annular powder chamber 13 is provided between the laser channel tube 12 and the welding body 1, and a powder feeding pipe 2 is connected to one side of the welding body 1. The powder feeding pipe 2 is connected to the annular powder chamber 13, and a powder feeder (not shown) is externally connected to the powder feeding pipe 2. The powder feeder can convey metal powder airflow into the powder feeding pipe 2;

[0033] A welding head 4 is provided below the welding body 1;

[0034] The outer wall of the welding body 1 is provided with a powder discharge mechanism 3, which is connected to the annular powder chamber 13. The powder discharge mechanism 3 can negatively suck the metal powder in the annular powder chamber 13, thereby reducing the powder feeding rate without changing and adjusting the powder feeder. Therefore, sudden blockage caused by metal powder in the powder feeding pipe 2 is avoided, and the continuity of powder feeding is guaranteed, preventing discontinuous flow of metal powder during adjustment of the powder feeder.

[0035] In this embodiment, a straight pipe 21 is vertically connected to the outside of the annular powder chamber 13, one end of the powder feeding pipe 2 is connected to the straight pipe 21, a conduit 22 is coaxially arranged in the straight pipe 21, and a plurality of ribs 24 are obliquely distributed in the conduit 22. The ribs 24 can be distributed in a circular cross-distribution, but are not in contact with each other to ensure that the metal powder can flow normally.

[0036] As a preferred embodiment, a plurality of ultrasonic transducers 23 are provided on the inner wall of the straight tube 21, and the ultrasonic transducers 23 are connected to the conduit 22, so that the ultrasonic transducers 23 can provide a radial vibration effect to the conduit 22, and the ribs 24 in the conduit 22 can break up the metal powder clusters during the vibration, thereby promoting the uniform dispersion of the metal powder in the airflow.

[0037] In this embodiment, spiral streamlines are distributed circumferentially on the outer wall of the laser channel tube 12, and an air inlet 14 is provided on the side wall of the welding body 1 near the upper end of the laser channel tube 12, wherein the air inlet 14 can be used to deliver both auxiliary gas and welding airflow. After the gas enters the welding body 1, it can generate a vertical downward spiral flow along the spiral streamlines on the surface of the laser channel tube 12, thereby combining with the metal powder airflow entering the welding body 1, prompting the metal powder airflow to also produce a spiral flow effect.

[0038] In this embodiment, the powder discharge mechanism 3 includes a powder discharge pipe 31, which is connected to the outside of the welding body 1. The inner circumference of the welding body 1 is provided with a plurality of axially distributed inner channels 32, and the inner wall of the welding body 1 is provided with an annular bin 33. The upper end of each inner channel 32 is connected to the annular bin 33, and the powder discharge pipe 31 is connected to the annular bin 33. The powder discharge pipe 31 can provide negative pressure suction, so that the metal powder in the inner channel 32 is collected and enters the annular bin 33.

[0039] A plurality of guide holes 34 corresponding to the inner channel 32 are further defined in the side wall of the welding body 1 , and the guide holes 34 are connected to the inner channel 32 .

[0040] In this embodiment, each of the guide holes 34 extends tangentially along the circumference of the annular powder chamber 13, and the extension direction of the guide holes 34 is opposite to the direction of the spiral streamline. In this way, the metal powder airflow flowing spirally downward will not directly enter the guide holes 34, resulting in most of the metal powder remaining on the surface of the guide holes 34. At the same time, the multiple guide holes 34 can also achieve a uniform suction and dispersion effect when negatively pressure sucking the metal powder airflow, preventing disturbance of the metal powder airflow and causing uneven flow.

[0041] As a preferred embodiment, a shut-off sleeve 35 is provided in each of the guide holes 34 , a valve core 36 is provided in the shut-off sleeve 35 , and one end of the valve core 36 is connected to a support spring, thereby achieving a blocking effect on the guide hole 34 .

[0042] In this embodiment, a powder feeding nozzle 41 is slidably installed inside the welding head 4, and an inner spring 42 is provided on the outer sleeve of the powder feeding nozzle 41; a vibrator 43 is installed on one side of the welding head 4, and the output end of the vibrator 43 is rotatably connected to a shaft 44, and the other end of the shaft 44 is connected to the powder feeding nozzle 41, wherein the vibrator 43 can provide a vibration effect. At this time, the shaft 44 can drive the powder feeding nozzle 41 to move axially back and forth during the operation of the vibrator 43, thereby realizing vibration powder discharge, wherein the vibrator 43 can also use the shaft 44 to adjust the displacement of the powder feeding nozzle 41, thereby changing the size of the powder flow gap of the powder feeding nozzle 41.

[0043] In this embodiment, the powder spraying port of the powder feeding nozzle 41 is configured as a conical structure.

[0044] The intelligent laser cladding welding process with dynamically adjusted powder feeding rate includes the following steps:

[0045] Step 1: Before laser welding, select metal powder that matches the workpiece, ensure that the dryness, fluidity, and particle size distribution meet the requirements, and load the powder into the powder feeder; set the working power of the laser welder and the powder feeder's powder feed rate so that the powder feed rate reaches the maximum set value for the powder feed required for laser cladding;

[0046] Step 2: Start the welding operation. The welding body 1 is laser-clad along a predetermined trajectory. The powder feeder sends a flow of metal powder into the conduit of the straight pipe 21. The conduit 22 can generate radial high-frequency vibration under the vibration of the ultrasonic transducer 23. The metal powder flows through the internal ribs 24 in the conduit 22 and is fully dispersed.

[0047] Step 3: After entering the annular powder chamber 13, the metal powder flows vertically downward. At the same time, the air inlet guides auxiliary air into the annular powder chamber 13, thereby causing the metal powder to generate a spiral flow along a spiral streamline in the annular powder chamber 13. At the same time, the powder discharge pipe 31 in the powder discharge mechanism 3 provides a negative pressure suction effect to suck out a portion of the metal powder, thereby reducing the amount of powder fed into the welding head 4, so that the actual amount of metal powder ejected from the welding head 4 just meets the expected standard for welding cladding.

[0048] Step 4: The vibrator 43 axially adjusts the powder feeding nozzle 41 based on the actual amount of metal powder ejected by the welding head 4, thereby changing the size of the internal flow gap and providing vibration powder discharge based on the dryness and particle size of the metal powder.

[0049] The above is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with this technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solutions and inventive concepts of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. Intelligent laser cladding welding device with dynamic powder feeding rate adjustment, characterized by: It comprises a laser collimator (11), the lower end surface of which is mounted with a welding body (1), wherein a laser channel tube (12) is coaxially arranged in the welding body (1); An annular powder chamber (13) is provided between the laser channel tube (12) and the welding body (1), and a powder feeding pipe (2) is connected to one side of the welding body (1), the powder feeding pipe (2) is connected to the annular powder chamber (13), and a powder feeder is externally connected to the powder feeding pipe (2); A welding head (4) is provided below the welding body (1); The outer side wall of the welding body (1) is provided with a powder discharge mechanism (3), and the powder discharge mechanism (3) is connected to the annular powder chamber (13).

2. The intelligent laser cladding welding device with dynamically adjustable powder feeding rate according to claim 1 is characterized in that: A straight pipe (21) is vertically connected to the outside of the annular powder chamber (13), one end of the powder delivery pipe (2) is connected to the straight pipe (21), a guide tube (22) is coaxially arranged in the straight pipe (21), and a plurality of ribs (24) are obliquely distributed in the guide tube (22).

3. The intelligent laser cladding welding device with dynamically adjustable powder feeding rate according to claim 2 is characterized in that: A plurality of ultrasonic transducers (23) are provided on the inner wall of the straight-through pipe (21), and the ultrasonic transducers (23) are connected to the conduit (22).

4. The intelligent laser cladding welding device with dynamically adjustable powder feeding rate according to claim 1 is characterized in that: Spiral streamlines are distributed circumferentially on the outer wall of the laser channel tube (12), and an air inlet (14) is provided on the side wall of the welding body (1) near the upper end of the laser channel tube (12).

5. The intelligent laser cladding welding device with dynamically adjustable powder feeding rate according to claim 4 is characterized in that: The powder discharge mechanism (3) includes a powder discharge pipe (31) connected to the outside of the welding body (1); a plurality of axially distributed inner channels (32) are provided on the inner circumference of the welding body (1); an annular bin (33) is provided on the inner wall of the welding body (1); the upper end of each inner channel (32) is connected to the annular bin (33); and the powder discharge pipe (31) is connected to the annular bin (33); A plurality of guide holes (34) corresponding to the inner channel (32) are also provided in the side wall of the welding body (1), and the guide holes (34) are connected to the inner channel (32).

6. The intelligent laser cladding welding device with dynamically adjustable powder feeding rate according to claim 5 is characterized in that: Each of the guide holes (34) extends tangentially along the circumference of the annular powder chamber (13), and the extending direction of the guide holes (34) is opposite to the direction of the spiral streamline.

7. The intelligent laser cladding welding device with dynamically adjustable powder feeding rate according to claim 5, characterized in that: A shutoff sleeve (35) is provided in each of the guide holes (34), a valve core (36) is provided in the shutoff sleeve (35), and one end of the valve core (36) is connected to a support spring.

8. The intelligent laser cladding welding device with dynamically adjustable powder feeding rate according to claim 1 is characterized in that: A powder feeding nozzle (41) is slidably mounted inside the welding head (4), and an inner spring (42) is provided on the outer shell of the powder feeding nozzle (41); a vibrator (43) is mounted on one side of the welding head (4), and an output end of the vibrator (43) is rotatably connected to a shaft (44), and the other end of the shaft (44) is connected to the powder feeding nozzle (41).

9. The intelligent laser cladding welding device with dynamically adjustable powder feeding rate according to claim 8, characterized in that: The powder injection port of the powder feeding nozzle (41) is configured as a conical structure.

10. An intelligent laser cladding welding process with dynamically adjustable powder feeding rate, which uses the intelligent laser cladding welding device with dynamically adjustable powder feeding rate according to any one of claims 1 to 9, characterized in that: It includes the following steps: Step 1: Before laser welding, select metal powder that matches the workpiece, ensure that the dryness, fluidity, and particle size distribution meet the requirements, and load the powder into the powder feeder; set the working power of the laser welder and the powder feeder's powder feed rate so that the powder feed rate reaches the maximum set value for the powder feed required for laser cladding; Step 2: Starting the welding operation, the welding body (1) is laser-clad along a predetermined trajectory, and the powder feeder sends the metal powder airflow into the conduit of the straight pipe (21). The conduit (22) can generate radial high-frequency vibration under the vibration of the ultrasonic transducer (23), and the metal powder flows through the internally arranged ribs (24) in the conduit (22) and is fully dispersed; Step 3: After the metal powder enters the annular powder chamber (13), it flows vertically downward, and at the same time, the air inlet guides the auxiliary air into the annular powder chamber (13), so that the metal powder generates a spiral flow along the spiral streamline in the annular powder chamber (13); at the same time, the powder discharge pipe (31) in the powder discharge mechanism (3) provides a negative pressure suction effect, sucking out a part of the metal powder, reducing the amount of powder fed into the welding head (4), so that the actual amount of metal powder ejected from the welding head (4) just meets the expected standard of welding cladding; Step 4: The vibrator (43) axially adjusts the powder feeding nozzle (41) based on the actual amount of metal powder ejected by the welding head (4), thereby changing the size of the internal flow gap, and provides vibration powder discharge based on the dryness and particle size of the metal powder.

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