Device special for on-line machining of weld joints in pipeline

Abstract

The invention belongs to the technical field of nuclear power station pipeline internal weld joint processing, and particularly relates to a special online processing device for pipeline internal weld joints. The eccentric tool bit is fixed to the eccentric tool rest base, the annular conical face push rod axially slides in the shell, the annular wedge block is installed on the shell, the annular wedge block is limited in the axial direction and stretches out and retracts in the circumferential direction of the shell, and the annular wedge block moves along with movement of the annular conical face push rod. The power connecting shaft is used for connecting and transmitting rotating power transmitted by a main shaft power source to the eccentric tool rest seat, so that circumferential rotation and axial movement of the eccentric tool rest seat are realized; a first air inlet and a second air inlet are formed in the tail of the shell. On-line machining is carried out on the internal weld joint of the high-temperature gas cooled reactor pneumatic lifting pipeline, the device can extend into the bulge of the internal weld joint of the pipeline to carry out on-line machining work, the machining precision of the pipeline weld joint in a narrow space is improved, clamping and blocking of a spherical element are avoided, and the reliability of pipeline equipment is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of internal weld processing of nuclear power plant pipelines, and particularly relates to a special device for on-line processing of internal welds of pipelines. Background Art

[0002] The pneumatic lifting pipeline of the fuel handling system of a high-temperature gas-cooled reactor nuclear power plant is a spherical pipeline that relies on pneumatic force to transport spherical components. The specification is ID62*6. After welding, spherical components with a diameter of Φ61mm need to pass through, and the unilateral allowance on the inner wall of the pipeline is 0.5mm. The existing technical solutions adopt a special welding process, with an inner concave chamfer of 0.5-1mm deep processed on the inner wall of the pipeline, and the T-shaped groove butt welding process is used. After welding, the inner wall of the welded pipeline is not allowed to protrude, and the inner concavity should be less than 0.4mm.

[0003] Since there are still steps at the T-shaped groove butt weld, there is a phenomenon of collision and wear of spherical components when passing through the weld, and there is a possibility of dust and debris accumulating at the weld. At the same time, due to the existence of steps, there will be a sudden change in the inner diameter of the pipeline, increasing the possibility of jamming and hovering of spherical components in the pipeline. Existing pipeline inner diameter processing equipment is applicable to pipelines with a diameter above There is no solution for the internal processing of long pipelines with a diameter.

[0004] Such as by performing on-line machining on the internal welds of pipelines with a diameter to remove the high points of the welds, the weld step problem can be effectively solved, and the welding efficiency can be greatly improved. Therefore, there is an urgent need for a device that can perform on-line processing of internal welds of pipelines to eliminate the current situation of sudden change in the inner diameter of the pipeline and the existence of steps, and improve the stability and reliability of the pneumatic lifting pipeline of the fuel handling system of a high-temperature gas-cooled reactor nuclear power plant. Summary of the Invention

[0005] The purpose of the present invention is to provide a special device for on-line processing of internal welds of pipelines, which can perform on-line processing on the internal welds of the pneumatic lifting pipelines of high-temperature gas-cooled reactors, can reach the raised parts of the internal welds of the pipelines, carry out on-line mechanical processing work, improve the processing accuracy of pipeline welds in narrow spaces, avoid jamming of spherical components, and improve the reliability of pipeline equipment.

[0006] To achieve the above purpose, the technical solutions adopted by the present invention are as follows:

[0007] A special device for online processing of internal welds in pipelines, wherein an eccentric cutter head is fixed on an eccentric cutter holder seat, an annular conical push rod slides axially on a shell body, an annular wedge is installed on the shell body, the annular wedge has a limited position in the axial direction, extends and retracts in the circumferential direction of the shell body, and moves with the movement of the annular conical push rod; a power access shaft is used to access and transmit the rotational power transmitted by the main shaft power source to the eccentric cutter holder seat, so as to realize the circumferential rotation and axial movement of the eccentric cutter holder seat; air inlet 1 and air inlet 2 are arranged at the rear of the shell body.

[0008] The eccentric cutter head throws out the tool by centrifugal force, and stable cutting is achieved by the contact between the front of the blade and the processing surface. The cutter head can adjust the required processing size in the diameter direction by adjusting the top screw and locking the top screw. This step is manual adjustment, and one processing size is adjusted at a time.

[0009] The shell includes a HALF shell, a tail shell, and an end cover, which is divided into two halves of the HALF shell in the axial direction. The end cover and the tail shell are distributed on the front and rear sides of the shell and are used to connect and fix the HALF shell. Air passages are set on the HALF shell and the tail shell. The air passage on the HALF shell is used for resetting the annular conical push rod, and the air passage on the tail shell is used for ejecting the annular conical push rod.

[0010] The eccentric tool holder seat is a circumferentially rotating part.

[0011] When the eccentric tool holder rotates forward along the cutting direction, it will also feed in the axial extension direction at the same time. The centrifugal force will throw the eccentric cutter head out, and the blade will contact the weld to be processed for cutting. When the cutting is completed, it will reverse the same number of turns. The eccentric cutter head will retract because the back of the blade hits the inner wall of the pipe, and the axial position of the eccentric tool holder will be reset.

[0012] When air is introduced into the second air inlet, the annular conical push rod pushes out the annular wedge to tighten and center it, thereby opening and fixing the entire online processing device. When air is introduced into the first air inlet, the annular wedge retracts and is retracted back to its original position by the external spring, thereby releasing the fixation of the entire online processing device.

[0013] Measure the misalignment of the two welded pipes, determine the maximum cutting allowance, and confirm that the misalignment meets the requirements; after determining that the misalignment value is within the effective range, first insert the endoscope into the pipe to check the weld position and the fixing position of the annular wedge block of the special device for on-line machining of the internal weld of the pipe for no welding slag or other foreign objects. After confirming no foreign objects, withdraw the endoscope; adjust the eccentric cutter head of the special device for on-line machining of the internal weld of the pipe to the initial size, control the depth of cut not to exceed the limit value, and manually retract the eccentric cutter head. Insert the special device for on-line machining of the internal weld of the pipe into the pipe. Estimate the distance dimension of the weld position through the small endoscope on the special device for on-line machining of the internal weld of the pipe, determine the positioning position of the special device for on-line machining of the internal weld of the pipe, send the special device to the weld position of the pipe to be machined, turn on the pneumatic switch, and the annular wedge block is pushed out and expanded by the annular conical surface push rod, automatically centering in the pipe and tightening the pipe wall to complete the fixation; start the special device, the eccentric tool rest seat starts to rotate, and the eccentric cutter head is thrown out. When the eccentric cutter head touches the high point of the weld, the tool starts to cut, and at the same time, the axial direction feeds at the same ratio. When the eccentric cutter head feeds in the axial direction and completes the weld cutting, the back of the eccentric cutter head rebounds when it touches the pipe wall during reverse rotation, and at the same time, the eccentric tool rest seat retracts in the axial direction, which is regarded as completing one cutting. After completion, adjust the pneumatic switch, the annular conical surface push rod retracts, the annular wedge block is retracted by the annular spring, the special device for on-line machining of the internal weld of the pipe is unlocked and fixed, and the special device for on-line machining of the internal weld of the pipe is withdrawn to complete one feed cutting; use the endoscope to check and clean the residual chips in the pipe with the air source, adjust the eccentric cutter head, adjust the depth of cut and then repeat the above actions for the second cutting; after two or three rounds of cutting, when the predetermined maximum machining size is reached, stop machining to ensure that the pipe body will not be damaged; complete the cutting process of this weld and carry out the subsequent grinding process.

[0014] When the eccentric cutter head feeds 20 mm in the axial direction and completes the weld cutting, the back of the eccentric cutter head rebounds when it touches the pipe wall during reverse rotation, and at the same time, the eccentric tool rest seat retracts 20 mm in the axial direction, which is regarded as completing one cutting.

[0015] The beneficial effects achieved by the present invention are as follows:

[0016] The present invention fills the gap in the on-line machining of the inner wall of small-diameter long-distance pipes. In cooperation with the endoscope, it can accurately machine the inner side welds of pipes in narrow-space pipes, remove the irregular high points of the welds, create a prerequisite for subsequent smooth transition of the pipe weld grinding, reduce the process requirements for pipe welding, improve the welding efficiency, and make the pneumatic lifting pipes of high-temperature gas-cooled reactors more reliable. Description of the Drawings

[0017] Figure 1 It is a schematic diagram of a special device for on-line machining of internal welds of pipes;

[0018] Figure 2Schematic diagram of the cutter head being thrown out and extended;

[0019] Figure 3 Schematic diagram of the supporting leg being extended and centered;

[0020] Figure 4 Schematic diagram of the special device for on-line machining of internal welds of pipelines and the connecting part;

[0021] In the figure: 1. Eccentric tool rest seat; 2. Eccentric cutter head; 3. HALF housing; 4. Ring wedge block (supporting leg); 5. Ring conical surface push rod; 6. Air inlet 1; 7. Power access shaft; 8. Air inlet 2; 9. Tail housing; 10. End head cover. Specific implementation mode

[0022] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] A special device for on-line machining of internal welds of pipelines includes an eccentric cutter head, a positioning and tightening automatic centering device, a device housing, a main shaft, and a feeding device; the eccentric cutter head 2 is fixed on the eccentric tool rest seat 1, and is designed to throw out the cutter by centrifugal force and achieve stable cutting by the contact between the front surface of the cutter blade and the machining surface. The cutter head can adjust the machining dimensions to be achieved by adjusting the set screw and the locking set screw in the diameter direction. This step is manual adjustment, and one machining dimension is adjusted at a time; the positioning and tightening automatic centering device includes a ring conical surface push rod and a ring wedge block. Among them, the ring conical surface push rod 5 slides axially in the housing, the ring wedge block 4 is limited axially, and is pushed out and retracted in the circumferential direction of the housing. The ring wedge block 4 acts with the movement of the ring conical surface push rod 5; the device housing includes a HALF housing, a tail housing, and an end head cover. The HALF housing 3 is split in half axially, and shaft parts such as a transmission lead screw and a transmission gear are placed in the center. The end head cover 10 and the tail housing 9 are distributed on the front and rear sides of the housing for connecting and fixing the HALF housing. Air channels are provided on the HALF housing and the tail housing. The air channel on the HALF housing is used for the reset of the ring conical surface push rod 5, and the air channel on the tail housing is used for the ejection of the ring conical surface push rod 5; the main shaft includes a power access shaft and an eccentric tool rest seat. The power access shaft 7 is used to access the rotational power transmitted by the main shaft power source and is transmitted to the eccentric tool rest seat 1 through an internal transmission device to achieve the circumferential rotation and axial movement of the eccentric tool rest seat; the feeding device includes transmission components such as gears and lead screws inside the housing and is used to achieve the axial movement of the eccentric tool rest.

[0024] As Figure 1 shown, the special device for on-line machining of internal welds of pipelines includes:

[0025] The eccentric tool rest base 1 is a circumferentially rotating part and is located at the very front of the entire device. The eccentric tool head 2 is located on the tool rest base. When the tool rest base rotates forward in the cutting direction, the axial extension direction will also feed simultaneously. The centrifugal force will throw out the eccentric tool head 2, and the blade will contact the weld to be machined for cutting. After the cutting is completed, reverse the same number of turns. The eccentric tool head retracts because the back of the blade collides with the inner wall of the pipe, and at the same time, the axial position of the eccentric tool rest base is reset. Figure 2 The figure shows the view of the throwing out of the tool head and the overall extension adjustment. Through the setscrew, the whole tool can be adjusted outward. Each time of machining, the setscrew needs to be adjusted manually. After adjusting the tool to the required position, lock it. Figure 3 The figure shows that the positioning and tensioning automatic centering device includes an annular wedge block 4 and an annular conical surface push rod 5. The annular wedge block 4 is installed on the equipment housing. When the second air inlet 8 intakes air, the annular conical surface push rod 5 will push out the annular wedge block 4 to expand and tighten for centering, and expand and fix the whole special device for on-line machining. When the first air inlet 6 intakes air, the annular wedge block 5 retracts, and the annular wedge block 4 retracts to its original position by the outer holding spring, and the fixation of the whole special device for on-line machining is released. Figure 4 The figure shows the tightening schematic diagram of the tightening and automatic centering device of the special device for on-line machining of internal welds of pipes. The tightening stroke is within 1.3 mm. If it exceeds the stroke, it cannot be used, and the thickness of the annular wedge block (support leg) needs to be adjusted to match the inner diameter of the pipe;

[0026] The working principle of the whole equipment: As Figure 1 shown in the figure, this special device for on-line machining requires two types of power sources, pneumatic and mechanical power. The pneumatic part is connected through the first air inlet 6 and the second air inlet 8 to realize the fixation and release of the whole special device for on-line machining. See Figure 3 ; The mechanical power part transmits the input power into the whole special device for on-line machining through the power access shaft 7. Through internal gears, transmission lead screws and other components, the power is transmitted to the eccentric tool rest base 1. The eccentric tool head 2 is driven to open in the circumferential direction by the centrifugal force. While the eccentric tool rest base 1 rotates forward, it also feeds axially at the same time to perform precise on-line machining of the inner wall weld of the pipe. After the machining is completed, reverse rotation realizes the retraction of the eccentric tool head 2 and the reset of the eccentric tool rest base 1, and completes one machining process.

[0027] Usage method: Implement on-line machining of internal welds of pipes;

[0028] The first step is to measure the misalignment amount of the two welded pipes and determine the maximum cutting allowance, and confirm that the misalignment amount meets the requirements; after determining that the misalignment value is within the effective range, it is necessary to first use an endoscope to go deep into the pipe to check the weld position and the fixing position of the support legs of the special device for on-line machining of internal welds of the pipe for no welding slag or other foreign objects. After confirming no foreign objects, withdraw the endoscope;

[0029] Adjust the tool bit of the special device for on-line machining of internal welds of pipelines to the initial size, control the depth of cut not to exceed the limit value, and manually retract the eccentric tool bit. Then, send the special device for on-line machining of internal welds of pipelines into the pipeline through the flexible shaft for power transmission. Estimate the distance dimension of the weld position through the small endoscope on the special device for on-line machining of internal welds of pipelines, determine the positioning position of the special device, and send the special device to the weld position of the pipeline to be machined. Open the pneumatic switch, and the annular wedge block (supporting foot) is pushed out and expanded by the annular push rod, automatically centering in the pipeline and tightening the pipe wall to complete the fixation;

[0030] Start the special device, the eccentric tool rest seat starts to rotate, and the eccentric tool bit is thrown out. When the tool bit touches the high point of the weld, the tool starts to cut, and at the same time, the axial direction feeds at the same ratio. When the tool bit feeds 20 mm in the axial direction, the weld cutting is completed. Reverse the equipment, the back of the tool bit touches the pipe wall and rebounds, and at the same time, the eccentric tool rest seat retracts 20 mm in the axial direction, which is regarded as completing one cutting. After completion, adjust the pneumatic switch, the annular push rod retracts, and the annular wedge block (supporting leg) is retracted by the annular spring. The special device for on-line machining of internal welds of pipelines is unlocked and fixed, and the special device for on-line machining of internal welds of pipelines is withdrawn to complete one feed cutting;

[0031] Use the endoscope to check and clean the residual chips in the pipeline with the air source. Adjust the tool bit, adjust the depth of cut, and then repeat the above actions for the second cutting; After two or three rounds of cutting, when the maximum predetermined machining size is reached, stop machining to ensure that the pipeline body will not be damaged; After completing the cutting process of this weld, the subsequent grinding process can be carried out.

[0032] In summary, for the special device for on-line machining of internal welds of pipelines provided by the present invention, when in use, connect the device to the power flexible shaft as shown in Figure 4 and the air pipe to provide the device with an air source and a mechanical power source, providing a new idea for the on-line machining of internal welds of the pneumatic lifting pipeline of the fuel handling system of the high-temperature gas-cooled reactor nuclear power plant.

Claims

1. A special device for online processing of internal welds in pipelines, characterized by: The eccentric cutter head is fixed on the eccentric tool holder seat, the annular conical push rod slides axially in the shell, the annular wedge is installed on the shell, the annular wedge has a limited position in the axial direction, and is extended and retracted in the circumferential direction of the shell, and the annular wedge moves with the movement of the annular conical push rod; the power access shaft is used to transfer the rotational power transmitted by the spindle power source to the eccentric tool holder seat, so as to realize the circumferential rotation and axial movement of the eccentric tool holder seat; air inlet 1 and air inlet 2 are arranged at the rear of the shell.

2. The dedicated device for online processing of internal welds of pipelines according to claim 1, characterized in that: The eccentric cutter head throws out the tool by centrifugal force, and stable cutting is achieved by the contact between the front of the blade and the processing surface. The cutter head can adjust the required processing size in the diameter direction by adjusting the top screw and locking the top screw. This step is manual adjustment, and one processing size is adjusted at a time.

3. The dedicated device for online processing of internal welds of pipelines according to claim 1 is characterized in that: The shell includes a HALF shell, a tail shell, and an end cover, which is divided into two halves of the HALF shell in the axial direction. The end cover and the tail shell are distributed on the front and rear sides of the shell and are used to connect and fix the HALF shell. Air passages are set on the HALF shell and the tail shell. The air passage on the HALF shell is used for resetting the annular conical push rod, and the air passage on the tail shell is used for ejecting the annular conical push rod.

4. The dedicated device for online processing of internal welds of pipelines according to claim 1, characterized in that: The eccentric tool holder seat is a circumferentially rotating part.

5. The dedicated device for online processing of internal welds of pipelines according to claim 1 is characterized in that: When the eccentric tool holder rotates forward along the cutting direction, it will also feed in the axial extension direction at the same time. The centrifugal force will throw the eccentric cutter head out, and the blade will contact the weld to be processed for cutting. When the cutting is completed, it will reverse the same number of turns. The eccentric cutter head will retract because the back of the blade hits the inner wall of the pipe, and the axial position of the eccentric tool holder will be reset.

6. The dedicated device for online processing of internal welds of pipelines according to claim 1, characterized in that: When air is introduced into the second air inlet, the annular conical push rod pushes out the annular wedge to tighten and center it, thereby opening and fixing the entire online processing device. When air is introduced into the first air inlet, the annular wedge retracts and is retracted back to its original position by the external spring, thereby releasing the fixation of the entire online processing device.

7. The dedicated device for online processing of internal welds of pipelines according to claim 1, characterized in that: Measure the misalignment of the two welded pipes, determine the maximum cutting allowance, and confirm that the misalignment meets the requirements; after determining that the misalignment value is within the effective range, use an endoscope to first penetrate into the pipe, check the weld position and the annular wedge fixing position of the special device for online processing of pipe internal welds to ensure that there is no welding slag or other foreign matter, and withdraw the endoscope after confirming that there is no foreign matter; adjust the eccentric cutter head of the special device for online processing of pipe internal welds to the initial size, control the cutting amount not to exceed the limit, and manually retract the eccentric cutter head, send the special device for online processing of pipe internal welds into the pipe, estimate the distance size of the weld position through the small endoscope on the special device for online processing of pipe internal welds, determine the positioning position of the special device for online processing of pipe internal welds, send the special device to the weld position of the pipe to be processed, turn on the pneumatic switch, and the annular wedge is pushed out and opened by the annular cone push rod, automatically centered in the pipe, and tightens the pipe wall to complete the fixation; start The special device starts to rotate the eccentric tool holder and throws out the eccentric cutter head. When the eccentric cutter head touches the high point of the weld, the tool starts cutting and feeds in the axial direction at the same proportion. When the eccentric cutter head feeds in the axial direction, the weld cutting is completed, the back of the reversed eccentric cutter head hits the pipe wall and rebounds, and the eccentric tool holder seat retreats in the axial direction, which is considered to have completed one cutting. After completion, the pneumatic switch is adjusted, the annular cone push rod retreats, and the annular wedge is retracted by the annular spring. The special device for online processing of the internal weld of the pipeline is unlocked and fixed, and the special device for online processing of the internal weld of the pipeline is pulled out to complete one feed cutting; use an endoscope to check and use the air source to clean the residual chips in the pipeline, adjust the eccentric cutter head, adjust the cutting amount and repeat the above actions for the second cutting; after two or three rounds of cutting, no more processing will be done after the predetermined maximum processing size is reached to ensure that the pipeline body will not be damaged; the cutting process of this weld is completed, and the subsequent grinding process is carried out.

8. The dedicated device for online processing of internal welds of pipelines according to claim 7, characterized in that: When the eccentric cutter head feeds 20mm in the axial direction to complete the weld cutting, the back of the reversed eccentric cutter head hits the pipe wall and rebounds, and the eccentric tool holder seat retreats 20mm in the axial direction, it is considered that one cutting is completed.

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