Welding and heat treatment integrated device for water bucket and rotating wheel of impulse turbine

Abstract

The invention relates to the technical field of impulse turbine production and processing, in particular to a welding and heat treatment integrated device for a water bucket and a rotating wheel of an impulse turbine, which comprises an execution unit for executing welding and annealing operations and a driving unit for driving the execution unit to move along a joint to be welded, the executing unit comprises an executing base connected with the output end of the driving unit, a welding mechanism and an annealing mechanism, the welding mechanism and the annealing mechanism are arranged on the executing base, and the welding mechanism can move along with the driving unit to conduct continuous and linear welding operation on a to-be-welded joint. The annealing mechanism can move along with the driving unit to conduct continuous and linear annealing operation on the welded connector, and an adjusting mechanism used for adjusting the distance between the welding mechanism and the annealing mechanism is further arranged on the execution base. The method is used for reducing the cost and manpower and material resource consumption in the welding and heat treatment process of the water bucket and the rotating wheel of the water turbine.

Description

Technical Field

[0001] The invention relates to the technical field of production and processing of impulse turbines, in particular to an integrated device for welding and heat treatment of a bucket and a runner of an impulse turbine. Background Art

[0002] With the continuous advancement of hydropower technology, large-scale impulse turbines play an important role in hydropower stations and hydropower generating units. As key components of turbines, the quality of buckets and runners directly affects the operating efficiency and stability of turbines. Especially at the connection between buckets and runners, welding is one of the core processes to ensure its strength and stability. However, residual stress will be generated during the welding process. If this stress is not effectively eliminated, it may cause cracks, deformation or fatigue failure of the welded joints, thus affecting the service life and operational safety of the turbine.

[0003] Therefore, annealing heat treatment after welding is a necessary process step. By heating the material and controlling the cooling rate, the internal stress generated during the welding process can be effectively eliminated, and the mechanical properties, fatigue resistance and crack resistance of the welded joint can be optimized. However, the existing heat treatment methods usually have the following problems: 1. Huge furnace chamber requirements: Large impulse turbines often require the use of large heat treatment furnaces for annealing and stress relief treatment. On the one hand, it takes up a lot of space and the investment cost is very high; on the other hand, the larger the volume of the furnace chamber, the lower the heat conduction efficiency, and it is difficult to achieve accurate heating and cooling of the welded joints. 2. Long heat treatment cycle: Since the furnace chamber of the heat treatment furnace needs to be gradually heated and cooled, the heat treatment process takes a long time to complete, which leads to an extension of the production cycle and an increase in energy consumption. 3. Welding and heat treatment need to be carried out independently. Heavy turbines consume a lot of manpower and material resources during transportation, furnace entry and furnace exit, which increases production costs and greatly reduces the heat treatment effect. Summary of the invention

[0004] The present invention aims to provide an integrated device for welding and heat treating a bucket and a runner of an impulse turbine, so as to reduce the cost and the consumption of manpower and material resources in the welding and heat treating process of the bucket and the runner of the turbine.

[0005] In order to solve the above technical problems, the specific solution adopted by the present invention is: an integrated welding and heat treatment device for the bucket and runner of an impulse turbine, including an execution unit for performing welding and annealing operations and a driving unit for driving the execution unit to move along the joint to be welded, the execution unit includes an execution base connected to the output end of the driving unit and a welding mechanism and an annealing mechanism arranged on the execution base, the welding mechanism can move with the driving unit to perform continuous linear welding operations on the joint to be welded, and the annealing mechanism can move with the driving unit to perform continuous linear annealing operations on the welded joint, and an adjustment mechanism for adjusting the spacing between the welding mechanism and the annealing mechanism is also provided on the execution base.

[0006] Preferably, a track for sliding cooperation of the welding mechanism and / or the annealing mechanism is provided on the execution base, so that the distance between the welding mechanism and the annealing mechanism can be adjusted by adjusting the sliding of the welding mechanism and / or the annealing mechanism along the track.

[0007] Preferably, the welding mechanism includes a welding slider slidably disposed on a track and a MIG welding assembly fixed on the welding slider; the annealing mechanism includes an annealing slider slidably disposed on the track and a laser annealing assembly fixed on the annealing slider.

[0008] Preferably, a welding temperature sensor for detecting the welding temperature is provided on the welding slider, and an annealing temperature sensor for detecting the annealing temperature is provided on the annealing slider.

[0009] Preferably, the welding temperature sensor and the annealing temperature sensor are both infrared temperature sensors.

[0010] Preferably, a position sensor for detecting the distance between the welding slider and the annealing slider is provided between the welding slider and the annealing slider.

[0011] Preferably, the execution base is provided with servo motors for driving the welding slider and the annealing slider to move along the track respectively.

[0012] Preferably, the annealing mechanism adopts a pulsed laser mode.

[0013] Preferably, the driving unit is a multi-degree-of-freedom robotic arm, and the execution base is connected to the output end of the multi-degree-of-freedom robotic arm through a rotating joint.

[0014] Preferably, the driving unit is a six-degree-of-freedom robotic arm.

[0015] The execution unit of the present invention is integrated with a welding mechanism and an annealing mechanism. When the execution unit is linearly moved along the joint to be welded by the driving unit, the welding operation of the joint to be welded and the heat treatment operation after welding can be completed simultaneously, and the welding-heat treatment cycle is reduced, thereby improving the operation efficiency.

[0016] In a preferred embodiment, laser annealing is used to heat treat the weld joint position. Laser annealing can optimize the residual stress distribution and inhibit the generation of cracks, thereby significantly improving the fatigue life, corrosion resistance and wear resistance of parts. Compared with traditional annealing methods, laser annealing has the advantages of fast, precise and local heating, and can eliminate the internal stress in the weld joint area without affecting the surrounding materials. It is suitable for welding heat treatment of buckets and runners in heavy-duty impulse turbines. In addition, the use of laser annealing can, on the one hand, solve the time, space and manpower consumption of traditional heat treatment processes in the heat treatment of heavy welded parts, and on the other hand, it can adjust the heat source with high precision for different materials, thereby achieving better stress relief effects.

[0017] In addition, on the one hand, the rapid temperature change during welding will produce residual stress in the weld. If heat treatment is performed immediately at this time, especially the local heating process of laser annealing, it may aggravate the redistribution of these residual stresses and even cause cracks, deformation and other problems; on the other hand, if the welded joint can undergo a certain cooling process before heat treatment after welding, it can help the temperature of the welding area to gradually balance and reduce the stress concentration caused by too fast heating. During the cooling process, the material will gradually return to a more stable physical state, providing better conditions for subsequent heat treatment. At this time, further heat treatment can accurately adjust the thermal impact of the welded joint and avoid the influence of unevenness during the cooling process.

[0018] In view of this, the spacing between the welding mechanism and the annealing mechanism in the present invention is controllable, so that in the process of continuous linear movement of the execution unit along the joint to be welded controlled by the driving unit, the spacing between the welding mechanism and the annealing mechanism can be adjusted to generate a time interval between the welding and heat treatment operations of the welding joint, and the time interval can be adjusted to increase the spacing between the welding mechanism and the annealing mechanism when the welding joint is large and the temperature in the welding area is too high; reduce the spacing between the welding mechanism and the annealing mechanism when the welding joint is small or partial welding and the heat affected zone of the welding joint is small, thereby further improving the welding and heat treatment effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The present invention is a schematic structural diagram of an integrated device for welding and heat treatment of a bucket and a runner of an impulse turbine.

[0020] Figure 2 for Figure 1 Schematic diagram of the main structure of the execution unit part.

[0021] Markings in the figure: 1. base, 2. integrated hose, 3. drive unit, 4. execution unit, 5. track, 6. annealing mechanism, 601. annealing slider, 602. annealing hose, 603. laser annealing assembly, 604. annealing temperature sensor, 7. execution base, 8. welding mechanism, 801. welding temperature sensor, 802. MIG welding assembly, 803. welding slider, 804. welding hose, 9. rotating joint. DETAILED DESCRIPTION

[0022] like Figure 1 and Figure 2 As shown, the present invention is an integrated device for welding and heat treatment of the bucket and runner of an impulse turbine. By integrating the welding mechanism 8 and the annealing mechanism 6 in the same execution unit 4, the integrated operation of welding and heat treatment is realized, the production process is optimized, and the quality of the welded joint is improved. A six-degree-of-freedom mechanical arm is used as the driving unit 3 to drive the execution unit 4 to move continuously linearly along the joint to be welded, and welding and annealing operations are performed in sequence during the movement, ensuring the precise coordination and efficient operation between the welding mechanism 8 and the annealing mechanism 6, thereby greatly improving the production efficiency and reducing the space occupied by the equipment. In addition, the spacing between the welding mechanism 8 and the annealing mechanism 6 is adjustable, which ensures that the joints of different materials and different specifications and shapes have high welding quality.

[0023] The driving unit 3 is fixed to the ground through the base 1, and can flexibly adjust the position of the execution unit 4 in space, so that the execution unit 4 can move along the joint to be welded between the bucket and the impeller of the turbine, and ensure that the execution unit 4 can perform precise operations under different welding and annealing requirements.

[0024] The execution unit 4 has an execution base 7 for the welding mechanism 8 and the annealing mechanism 6 to carry. The top of the execution base 7 is connected to the output end of the driving unit 3 through a rotating joint 9, and a track 5 is provided at the bottom for the welding mechanism 8 and the annealing mechanism 6 to be installed and slidably matched. The welding mechanism 8 includes a welding slider 803 slidably mounted on the track 5, and a MIG welding assembly 802 and a welding temperature sensor 801 fixed on the welding slider 803. The annealing mechanism 6 includes an annealing slider 601 slidably mounted on the track 5, and a laser annealing assembly 603 and an annealing temperature sensor 604 fixed on the annealing slider 601. The laser annealing assembly 603 adopts a pulsed laser mode to adjust the output time and power of the laser, thereby optimizing the thermal impact of the welding joint area and avoiding deformation or cracks in the welding area caused by excessive heating. Two servo motors are also provided on the execution base 7, and the two servo motors are connected to the welding slider 803 and the annealing slider 601 through the screw assembly, respectively, to drive the welding slider 803 and the annealing slider 601 to move along the track 5, so as to adjust the distance between the MIG welding assembly 802 and the laser annealing assembly 603. A position sensor pointing to the annealing slider 601 is also provided on the welding slider 803, so as to detect the distance between the two through the position sensor. The above technical solutions of using the servo motor and the screw assembly to drive the slider to move along the track 5 and detecting the distance between the two objects through the position sensor are conventional technical means in the field, which will not be repeated here and are not shown in the figure.

[0025] The MIG welding assembly 802 is also connected to a welding hose 804 for welding wire feeding, and the laser annealing assembly 603 is also connected to an annealing hose 602 for optical fiber connection. The welding hose 804 and the annealing hose 602 are connected to the integrated hose 2 through the internal channel of the drive unit 3, and the integrated hose 2 is connected to the main control cabinet. The integrated hose 2 is a multifunctional hose that can transmit welding wire, optical fiber, and electricity to various components through the hose system, thereby achieving a simplified pipeline layout and convenient operation management. The welding temperature sensor 801 and the annealing temperature sensor 604 are both infrared temperature sensors that can detect the surface temperature of the welding joint area in real time, so that personnel can adjust the power output and laser scanning rate of the laser generator to ensure the temperature control accuracy during the annealing process.

[0026] Based on the above technical solution, the working process of the present invention is as follows.

[0027] 1. Before welding, the water bucket and the runner need to be cut, polished, deburred and other pre-processed according to the design requirements to ensure the flatness and welding quality of the welding joint.

[0028] 2. Fix the pre-welding position of the water bucket and the runner, adjust the distance between the MIG welding assembly 802 and the laser annealing assembly 603, control the execution unit 4 to move along the joint to be welded by the driving unit 3, start welding through the MIG welding assembly 802, and perform heat treatment on the welding area through the laser annealing assembly 603.

[0029] 3. The welding work is completed first, and after the laser annealing work is completed, the position of the execution unit 4 can be adjusted through the driving unit 3 to start the welding of the next pair of buckets and the runner.

[0030] The reasons for setting a spacing between the MIG welding component 802 and the laser annealing component 603 and adjusting the spacing according to different materials and different specifications and shapes are: (1) Rapid temperature changes during welding will generate residual stress in the weld. If heat treatment is performed immediately at this time, especially local heating processes such as laser annealing, it may aggravate the redistribution of these residual stresses and even cause problems such as cracks and deformation; (2) The welded joint will undergo a certain cooling process after welding, which can help the temperature of the welding area gradually balance and reduce stress concentration caused by excessive heating. During the cooling process, the material will gradually return to a more stable physical state, providing better conditions for subsequent heat treatment. At this time, further heat treatment can accurately adjust the thermal impact of the welded joint and avoid the influence of unevenness during the cooling process.

[0031] The factors that affect the spacing adjustment between the MIG welding assembly 802 and the laser annealing assembly 603 are: the size of the welding area. If the welding area is large, the spacing needs to be increased to ensure that the laser annealing can cover the entire welding area; if the welding area is small, the spacing is reduced to concentrate the heat of the laser on the welding joint; the cooling rate of the welding joint. Adjusting the spacing between welding and heat treatment can control the uniformity of the cooling rate. In the case of slower cooling, the temperature of the welding joint will be more stable, providing better conditions for subsequent laser annealing; the characteristics of the welded materials. The welding joints of some materials require stronger local heating to remove stress, and the spacing can be reduced at this time; in other cases, more space is needed to ensure the uniformity of heat treatment, and the spacing needs to be appropriately increased.

[0032] In summary, the situation where the spacing needs to be increased is: the weld joint is large; the temperature in the welding area is too high. The cooling rate of the weld joint needs to be more accurately controlled. The situation where the spacing needs to be decreased is: the weld joint is small or partial welding; the heat affected zone of the weld joint is small.

Claims

1. An integrated device for welding and heat treatment of bucket and runner of impulse turbine, characterized in that: The invention comprises an execution unit (4) for executing welding and annealing operations and a driving unit (3) for driving the execution unit (4) to move along a joint to be welded. The execution unit (4) comprises an execution base (7) connected to an output end of the driving unit (3) and a welding mechanism (8) and an annealing mechanism (6) arranged on the execution base (7). The welding mechanism (8) can move with the driving unit (3) to perform a continuous linear welding operation on the joint to be welded. The annealing mechanism (6) can move with the driving unit (3) to perform a continuous linear annealing operation on the welded joint. An adjusting mechanism for adjusting the distance between the welding mechanism (8) and the annealing mechanism (6) is also arranged on the execution base (7).

2. The integrated device for welding and heat treatment of bucket and runner of impulse turbine according to claim 1, characterized in that: A track (5) for slidingly engaging the welding mechanism (8) and / or the annealing mechanism (6) is provided on the execution base (7), so that the distance between the welding mechanism (8) and the annealing mechanism (6) can be adjusted by adjusting the sliding of the welding mechanism (8) and / or the annealing mechanism (6) along the track (5).

3. The integrated device for welding and heat treatment of bucket and runner of impulse turbine according to claim 2, characterized in that: The welding mechanism (8) comprises a welding slider (803) slidably disposed on the track (5) and a MIG welding assembly (802) fixed on the welding slider (803); the annealing mechanism (6) comprises an annealing slider (601) slidably disposed on the track (5) and a laser annealing assembly (603) fixed on the annealing slider (601).

4. The integrated device for welding and heat treatment of bucket and runner of impulse turbine according to claim 3, characterized in that: A welding temperature sensor (801) for detecting welding temperature is provided on the welding slider (803), and an annealing temperature sensor (604) for detecting annealing temperature is provided on the annealing slider (601).

5. The integrated device for welding and heat treatment of bucket and runner of impulse turbine according to claim 4, characterized in that: The welding temperature sensor (801) and the annealing temperature sensor (604) are both infrared temperature sensors.

6. The integrated device for welding and heat treatment of bucket and runner of impulse turbine according to claim 3, characterized in that: A position sensor for detecting the distance between the welding slider (803) and the annealing slider (601) is provided between the welding slider (803) and the annealing slider (601).

7. The integrated device for welding and heat treatment of bucket and runner of impulse turbine according to claim 3, characterized in that: The execution base (7) is provided with servo motors for respectively driving the welding slider (803) and the annealing slider (601) to move along the track (5).

8. The integrated device for welding and heat treatment of bucket and runner of impulse turbine according to claim 3, characterized in that: The annealing mechanism (6) adopts a pulsed laser mode.

9. The integrated device for welding and heat treatment of bucket and runner of impulse turbine according to claim 1, characterized in that: The driving unit (3) is a multi-degree-of-freedom mechanical arm, and the execution base (7) is connected to the output end of the multi-degree-of-freedom mechanical arm via a rotating joint (9).

10. The integrated device for welding and heat treatment of bucket and runner of impulse turbine according to claim 9, characterized in that: The driving unit (3) is a six-degree-of-freedom robotic arm.

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