CN212144963U - Connecting system of heat exchange tube and tube plate - Google Patents

Connecting system of heat exchange tube and tube plate Download PDF

Info

Publication number
CN212144963U
CN212144963U CN201922472881.8U CN201922472881U CN212144963U CN 212144963 U CN212144963 U CN 212144963U CN 201922472881 U CN201922472881 U CN 201922472881U CN 212144963 U CN212144963 U CN 212144963U
Authority
CN
China
Prior art keywords
heat exchange
tube
expansion
welding
exchange tube
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201922472881.8U
Other languages
Chinese (zh)
Inventor
谢彦武
金刚
王莉
张立德
杨云丽
赵福冬
李树辉
谭永林
邹亮
冶金辉
夏从鑫
张美美
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Harbin Electric Group Qinhuangdao Heavy Equipment Co Ltd
Original Assignee
Harbin Electric Group Qinhuangdao Heavy Equipment Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Harbin Electric Group Qinhuangdao Heavy Equipment Co Ltd filed Critical Harbin Electric Group Qinhuangdao Heavy Equipment Co Ltd
Priority to CN201922472881.8U priority Critical patent/CN212144963U/en
Application granted granted Critical
Publication of CN212144963U publication Critical patent/CN212144963U/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Landscapes

  • Laser Beam Processing (AREA)

Abstract

The utility model discloses a connected system of heat exchange tube and tube sheet, this connected system include heat exchange tube, tube sheet, location expanded joint equipment and laser-beam welding machine. When the connecting system of the heat exchange tube and the tube plate is used for connecting the heat exchange tube and the tube plate, the welding process is stable, the automation degree and the working efficiency are high, the welding seam is formed uniformly, the fusion of the root part of the heat exchange tube is good, and the technical index of the minimum leakage channel can meet the requirements of products and related technical documents.

Description

Connecting system of heat exchange tube and tube plate
Technical Field
The utility model relates to a nuclear power field, concretely relates to connecting system of heat exchange tube and tube sheet, in particular to connecting system of AP1000 steam generator heat exchange tube and tube sheet.
Background
The heat exchange tube and tube plate connecting weld joint plays a role in isolating medium fluids with different pressures and different temperatures, the connecting weld joint also plays a role in supporting the tube plates under some conditions, products such as a nuclear island main equipment steam generator, a waste heat discharge heat exchanger and the like are designed with the heat exchange tube and the tube plate for welding, and the current mainstream welding mode of the weld joint is Gas Tungsten Arc Welding (GTAW).
The tig welding is a welding method in which a base metal or a filler wire (if a filler wire is used) is melted by an arc generated between a tungsten electrode and a workpiece under the protection of an inert gas. Because the inert gas is continuously fed in the high-temperature fusion welding, the adverse effects of oxygen, nitrogen, hydrogen and the like in the air on electric arcs and a molten pool can be isolated, and the burning loss of alloy elements is reduced, so that a compact, high-quality and purer welding joint is obtained.
However, tig welding depth, low deposition speed and low work rate in tig welding. In addition, for welding of a heat exchange tube and a tube plate in the nuclear power field, the problem that the important index of the minimum leakage channel is not superior exists.
SUMMERY OF THE UTILITY MODEL
In order to solve the above problems, the present inventors have conducted intensive studies and, as a result, have found that: adopt automatic laser welding machine to weld the heat exchange tube after the expanded joint and tube sheet under specific welding parameter, not only welding process is stable, degree of automation and work efficiency are high, and the welding seam after the welding takes shape evenly moreover, and the heat exchange tube root fuses well, can improve minimum leakage channel average value under the condition of guaranteeing the penetration of welding seam, thereby has accomplished the utility model discloses.
Particularly, the utility model aims to provide a connected system of heat exchange tube and tube sheet, the system includes heat exchange tube, tube sheet, location expanded joint equipment and automatic laser-beam welding machine.
The automatic laser welding machine is used for welding and connecting the heat exchange tube and the tube plate;
wherein, a nickel-based surfacing layer is surfaced on the primary side surface of the tube plate, and the assembling form of the heat exchange tube and the tube plate is selected to be flat;
the automatic welding machine comprises a workbench, a laser welding gun, a laser generator and a shielding gas device;
the positioning expansion joint device comprises an expansion gun, a positioning expansion head and a plug gauge.
The positioning expansion head comprises an expansion rod, a front end nut, a rear end connecting seat, a split ring and a rubber ring;
the rubber circle includes I type rubber circle and II type rubber circle, and I type rubber circle includes a plurality ofly, and I type rubber circle sets up the both sides at II type rubber circle.
The utility model provides a connection system of heat exchange tube and tube sheet has following beneficial effect:
(1) the connecting system provided by the utility model adopts the automatic laser welding process to replace the gas shielded tungsten arc welding, and the process can carry out programming control on welding process parameters and processes, has the automatic control function, and has stable welding process and high working efficiency;
(2) the connecting system provided by the utility model adopts specific technological parameters for welding, so that good weld forming and weld fusion can be obtained, and the welding quality meets the product requirements;
(3) the utility model provides a connected system can improve the welding seam penetration of welding seam and minimum reveal the passageway, can promote 1.2mm by 0.9mm to for example the average value of revealing the passageway by the minimum of the welding seam that tungsten utmost point gas shielded welding obtained.
Drawings
FIG. 1 shows a block diagram of a laser welder according to a preferred embodiment of the present invention;
fig. 2 shows an assembly view of a heat exchange tube and a tube sheet according to a preferred embodiment of the present invention;
fig. 3 shows a block diagram of an expansion head according to a preferred embodiment of the present invention;
fig. 4 shows a schematic diagram of the expansion process according to a preferred embodiment of the present invention.
The reference numbers illustrate:
1-heat exchange tube;
2-a tube plate;
21-surfacing layer;
3-laser welding gun;
4-a laser generator;
5-a power supply control device;
6-a cooler;
7-operating panel;
81-expanding rod;
82-front end nut;
83-rear end connecting seat;
84-split ring;
85-rubber ring;
851-I type rubber rings;
852-II type rubber ring;
9-a shielding gas device;
10-a workbench;
11-gun inflation.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples. The features and advantages of the present invention will become more apparent from the description.
The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.
The present invention is described in detail below.
The heat exchange tube and the tube plate of the steam generator are generally connected by adopting a method of expansion joint first and then welding, before the heat exchange tube and the tube plate are welded, the heat exchange tube is fixed on the tube plate through expansion joint first, stress can be generated on the heat exchange tube and the tube plate in the expansion joint process, the stress can be gradually eliminated along with the time extension, the heat exchange tube and the tube plate can possibly fall off, once the heat exchange tube and the tube plate fall off, the expansion joint needs to be carried out again, and the heat exchange tube and the tube plate can be deformed due to repeated expansion joint operation, so that the heat exchange tube and the tube plate are damaged. It is therefore desirable to complete the weld as quickly as possible after the expansion joint is completed.
At present, the mainstream welding mode between a heat exchange tube and a tube plate of a steam generator is Gas Tungsten Arc Welding (GTAW), the welding is carried out by adopting the method, although the welding process is stable, the welding quality of the obtained welding line is high, the tungsten electrode needs to be replaced once after one heat exchange tube is welded, and the number of the heat exchange tubes on the tube plate is generally hundreds or thousands, so that the welding speed is low and the working efficiency is lower when the gas tungsten arc welding is adopted for welding.
In addition, the weld joint obtained by adopting gas tungsten arc welding has shallow fusion depth, the minimum leakage channel value is smaller, and the weld joint quality still needs to be improved.
Based on the structure, the utility model provides a connecting system of a heat exchange tube and a tube plate, which is preferably used for the connection between the heat exchange tube and the tube plate of a steam generator in the nuclear power field; further preferably, the connection between the heat exchange tube and the tube plate of the AP1000 steam generator is adopted.
In a preferred embodiment, the connection system comprises a heat exchange tube 1, a tube plate 2, a positioning expansion joint device and a laser welding machine.
The heat exchange tube is fixedly connected to the tube plate through expansion joint and welding, the positioning expansion joint equipment is used for expansion joint and fixation of the heat exchange tube and the tube plate, and the laser welding machine is used for welding connection of the heat exchange tube and the tube plate.
The utility model discloses in, the location expanded joint is established and is included: the expansion gun 11, a positioning expansion head matched with the heat exchange tube and a plug gauge for detecting the expansion joint length.
The utility model discloses in, the head is expanded in location includes expander roll 81, front end nut 82, rear end connecting seat 83, split circle 84 and rubber circle 85.
One end of the expansion rod 81 is connected with a rear end connecting seat 83 through a unthreaded hole, wherein an external thread is arranged on the rear end connecting seat 83, the rear end connecting seat 83 is used for being connected with an expansion gun, and the expansion rod 81 is driven to move by the expansion gun; the other end of the expansion rod 81 is connected with the front end nut 82 through a threaded hole, wherein the front end nut 82 can be driven by the expansion rod 81 to move for extruding the rubber ring 85.
The front end nut 82 is bullet shaped. This is because the sectional area of the front end of the bullet-shaped nut is gradually reduced, and the expansion head can be conveniently inserted into the heat exchange tube.
The split ring 84 is sleeved on the expansion rod 81 and fixedly connected with the rear end connecting seat 83.
The rubber ring 85 is sleeved on the expansion rod 81 and is positioned between the front end nut 82 and the split ring 84.
Preferably, the rubber ring 85 comprises a type I rubber ring 851 and a type II rubber ring 852, and the hardness of the type I rubber ring 851 is slightly larger than that of the type II rubber ring 852. Wherein, I type rubber circle 851 includes a plurality ofly, and I type rubber circle 851 sets up the both sides at II type rubber circle 852.
Further preferably, the type II rubber ring 852 includes a plurality. For example, the rubber ring 85 includes 2I-type rubber rings 851 and 2 II-type rubber rings 852, and the I-type rubber rings 851, the II-type rubber rings 852, and the I-type rubber rings 851 are arranged on the expander 81 in this order.
The utility model discloses in, laser-beam welding machine is automatic laser-beam welding machine. The automatic welding machine comprises a workbench 10, a laser welding gun 3, a laser generator 4, a power supply control device 5, a cooler 6, an operation panel 7 and a shielding gas device 9.
Adopt the utility model provides a connected system connects heat exchange tube and tube sheet, can improve the quality of being connected of heat exchange tube and tube sheet, and the gained welding seam is not only melted deeply big, can promote the average value of revealing the passageway by 0.9mm to 1.2mm with the minimum of the welding seam that obtains by tungsten utmost point gas shielded welding moreover.
The utility model also provides an utilize the utility model provides a method that the connecting system of heat exchange tube and tube sheet is connected, the connecting method includes following step:
step 1, cleaning a tube plate;
wherein, the utility model discloses in, the heat exchange tube does not need itself to wash for the finished product purchase. However, the cutting oil used in the process of machining the tube holes of the tube plate pollutes the heat exchange tube and the tube plate, and causes difficulty in subsequent expansion joint and welding. Therefore, before connection, the tube plates need to be cleaned first to avoid impurities such as cutting oil or scrap iron in the welding process from mixing into the welding seam to cause welding seam defects such as air holes, slag inclusion or welding beading.
In a preferred embodiment, the cleaning is a manual wipe.
The pipe holes on the pipe plate have the characteristics of small inner diameter, large depth and large quantity, so the operation difficulty in cleaning is large. In order to ensure the cleanliness of the tube plate, the cleaning liquid is preferably dipped by the wiping rod to wipe the tube hole and the surface of the tube plate.
Wherein, the top end of the wiping rod is wrapped by white cloth or non-woven fabric which does not fall hair, and the adopted cleaning solution is preferably acetone. When cleaning, the cleaning was carried out strictly until the color was not changed by wiping with acetone in order to ensure the cleaning quality.
Step 2, expanding and connecting the heat exchange tube and the tube plate;
the utility model discloses in, when expanding joint, preferably adopt location expanded joint equipment to expand to connect fixedly to heat transfer pipe and tube sheet.
In a preferred embodiment, the positioning expansion joint device comprises an expansion gun 11, a positioning expansion head and a plug gauge.
The positioning expansion head comprises an expansion rod 81, a front end nut 82, a rear end connecting seat 83, a split ring 84 and a rubber ring 85, as shown in fig. 3.
In the utility model, one end of the expansion rod 81 is connected with the rear end connecting seat 83 through a unthreaded hole, wherein, an external thread is arranged on the rear end connecting seat 83, the rear end connecting seat 83 is used for being in threaded connection with an expansion gun, and the expansion rod 81 can be driven to move by the expansion gun; the other end of the expansion rod 81 is connected with the front end nut 82 through a threaded hole, wherein the front end nut 82 can be driven by the expansion rod 81 to move for extruding the rubber ring 85.
Preferably, the front end nut 82 is bullet shaped. This is because the sectional area of the front end of the bullet-shaped nut is gradually reduced, and the expansion head can be conveniently inserted into the heat exchange tube.
In the present invention, the split ring 84 is sleeved on the expansion rod 81 and is fixedly connected to the rear end connecting seat 83. The split ring 84 is provided to prevent the rubber ring 85 from moving axially under high pressure, and to ensure the expanded joint length.
In the present invention, the rubber ring 85 is sleeved on the expansion rod 81 and is located between the front end nut 82 and the split ring 84.
Preferably, the rubber ring 85 comprises a type I rubber ring 851 and a type II rubber ring 852. The hardness of the I-type rubber ring 851 is greater than that of the II-type rubber ring 852, the I-type rubber ring 851 comprises a plurality of I-type rubber rings, and the I-type rubber rings 851 are arranged on two sides of the II-type rubber ring 852.
The reason is that the rubber ring is hard and is not easy to deform, so that the expansion joint effect is influenced; if the soft part is too soft, the soft part is easily crushed, and the service life of the expansion head is reduced. The utility model discloses in, set up I type rubber circle 852 on the both sides of II type rubber circle 851 for soft on the middle of the hardness of rubber circle, both sides are hard slightly, can be under the condition of guaranteeing rubber circle deformation, avoid the rubber circle to be crowded garrulous or by crowded flat when direct and the metal contact under great pressure.
Further preferably, the type II rubber ring 852 includes a plurality. For example, the rubber ring 85 includes 2I-type rubber rings 851 and 2 II-type rubber rings 852, and the I-type rubber rings 851, the II-type rubber rings 852, and the I-type rubber rings 851 are arranged on the expander 81 in this order.
This is because the expansion force is provided to the heat exchange tube wall mainly by the deformation of the rubber ring during the expansion joint. Wherein, the rubber circle is expanded deformation, radial expansion when receiving axial compression, and then produces a very high expanded joint pressure, makes heat exchange tube and tube sheet hole take place to warp to closely laminate heat exchange tube and tube sheet together, reach fixed purpose. Under the condition of the same length, the deformability of a plurality of rubber rings is larger than that of a single rubber ring, therefore, the utility model discloses in preferably adopt 4 rubber rings.
In a preferred embodiment, before expansion joint, a positioning expansion head matched with the heat exchange tube is selected according to the size of the heat exchange tube, a rubber ring is sleeved on an expansion rod, and a front end nut is screwed down to ensure that the rubber ring is completely positioned on a polished rod part of the expansion rod.
Then, the heat exchange tube is adjusted to be flush with the surface of the tube plate, the positioning expansion head is inserted into the heat exchange tube, and the rear end connecting seat on the positioning expansion head is tightly propped against the primary side surface of the tube plate, as shown in fig. 4.
And then starting the expansion gun to enable the front end nut to move backwards under the pulling of the expansion rod so as to extrude the rubber ring, so that the rubber ring is expanded and deformed, and acting force generated by the expansion and deformation of the rubber ring is applied to the inner wall of the heat exchange tube to force the heat exchange tube and the tube hole to deform, so that the heat exchange tube and the tube plate are tightly attached together.
In the expansion joint process, a gun expansion starting switch needs to be pressed all the time, the indication of an indicator lamp on an operation panel of the gun expansion is observed, the switch is released after the completion of the expansion joint is confirmed, and the gun expansion is pulled out. During the gun pulling process, attention is paid to keeping the gun horizontal to ensure that the central line of the mandrel of the expansion rod is collinear with the axis of the pipe hole.
And finally, after the expanded joint is finished, checking whether the expanded joint length meets the requirement by using a plug gauge.
The utility model discloses in, the flush formula is chooseed for use to the assembly form of heat exchange tube and tube sheet, also is the mouth of pipe and the tube sheet parallel and level of heat exchange tube. The assembly error between the heat exchange tube and the tube plate, that is, the distance Δ h between the heat exchange tube and the primary side surface of the tube plate, is preferably ± 0.18mm, more preferably ± 0.15mm, and even more preferably ± 0.13mm, as shown in fig. 2.
The size of the assembly error not only can influence the forming of the welding seam, but also can influence the minimum leakage channel, the assembly error is controlled within the range, and the welding quality of the obtained welding seam is better.
And 3, installing and debugging welding equipment, setting welding parameters and carrying out welding.
The welding device is a laser welding machine, preferably a manual welding machine or an automatic welding machine, more preferably an automatic welding machine, as shown in fig. 1. The automatic welding machine comprises a workbench 10, a laser welding gun 3, a laser generator 4, a power supply control device 5, a cooler 6, an operation panel 7 and a shielding gas device 9.
The automatic welding machine can program and store welding parameters in advance, realize fine control on related parameters in the welding process, reduce the influence of human factors on the welding quality in the welding process, better ensure the welding seam forming and the welding quality and improve the welding efficiency.
When welding, the welding mode is preferably self-welding or filler wire welding, and more preferably self-welding. The welding seam obtained by adopting self-fusion welding is smoother, which is beneficial to controlling the welding quality.
The welding technological parameters and the laser welding effect of the laser welding machine are closely related to the material of the processed material. The utility model discloses in, the material of tube sheet is low alloy steel forging, preferably ferrite steel forging, further preferably SA-508Gr.3Cl.2 forging.
The material of the heat exchange tube is 304 austenitic stainless steel, 600 alloy, 800 alloy or 690 alloy, preferably 690 alloy, and more preferably SA-163UNS N06690.
Among them, 690 alloy is an austenite type nickel-based corrosion resistant alloy containing 30% of Cr, and has excellent capability of resisting erosion of various aqueous media and high-temperature atmosphere, good metallurgical stability and excellent processing characteristics. Particularly, the 690 fitting also has excellent intergranular corrosion resistance and intergranular stress corrosion cracking resistance, and can effectively avoid cracking and damage of the heat exchange tube.
The primary side of a tube plate of a steam generator of AP1000 nuclear power equipment is in direct contact with high-temperature water with radioactive substances in a primary loop of nuclear island main equipment, and a surfacing layer with a certain thickness is usually surfaced on the primary side surface of the tube plate in order to ensure the corrosion resistance and the oxidation resistance of the primary side surface of the tube plate and good weldability with a heat exchange tube.
In the present invention, a nickel-based overlay 21 is formed on the primary side surface of the tube sheet, and preferably, the thickness of the overlay is 5.2-8mm, more preferably 6-7mm, and still more preferably 6.6 mm.
Before the laser welding operation is carried out, the technological parameters of the laser welding are determined, wherein the technological parameters mainly comprise laser power, laser speed, spot diameter and protective gas.
In welding, laser power is an important parameter that determines the quality of the weld. Generally, the level of the laser power is directly related to the depth of the penetration depth, and the higher the laser power is, the deeper the penetration depth is.
Preferably, in the present invention, the laser welding power is 400-; preferably, the welding power of the laser welding is 600 w.
The welding speed can affect the heat input quantity in unit time, and if the welding speed is too high, the heat input quantity is too small, the workpiece is difficult to be welded through, and the fusion depth is generally shallow; if the welding speed is too slow, the heat input is too large, which may result in excessive melting of the workpiece and easy penetration of the weld.
Preferably, the utility model discloses in, welding speed is 0.8-1.2m/min, and further, welding speed is 0.9-1.1m/min, and better, welding speed is 1.0 m/min.
In laser welding, the spot diameter size is one of the important parameters of laser welding, and the spot diameter determines not only the power density but also the width of the weld. The utility model discloses in, after the expanded joint, the heat transfer pipe is in the same place with the pipe plate is hugged closely tightly, does not have the clearance between the two. And taking the outer wall of the heat exchange tube as a reference, and defining areas which are 0-1mm away from the left side and the right side of the outer wall of the heat exchange tube as welding areas. Preferably, the distance between the welding area and the left side and the right side of the outer wall of the heat exchange tube is 0-0.5mm, and more preferably, the distance between the welding area and the left side and the right side of the outer wall of the heat exchange tube is 0-0.35 mm.
When laser welding is carried out, laser spots fall in a welding area, the centers of the laser spots are positioned on the outer wall of the heat exchange tube, half of the laser spots are positioned on the tube wall of the heat exchange tube, and the other half of the laser spots are positioned on the tube plate, and under the irradiation of the laser, the tube wall of the heat exchange tube and the tube plate are gradually melted and fused together. The welding area is narrow, so the diameter of the light spot is not too large, the pipe wall of the heat exchange pipe is thin, and if the diameter of the light spot is too large, the pipe wall of the heat exchange pipe is easy to weld through; on the contrary, if the diameter of the light spot is too small, the obtained welding line is too thin, the connection strength between the tube plate and the heat exchange tube is not enough, and safety accidents are easily caused.
Preferably, in the present invention, the spot diameter is 0.5-1.0mm, more preferably 0.6-0.8mm, and still more preferably 0.7 mm.
The utility model discloses in, select for use inert gas to protect welding as the protective gas to avoid tube sheet and heat exchange tube to be heated the oxidation in welding process. The inert gas is selected from one or more of helium, argon or nitrogen, more preferably argon, still more preferably argon with the purity of more than or equal to 99.990%, for example argon with the purity of more than or equal to 99.997%.
Argon gas low price, density is great, and is better than the protection effect of nitrogen gas, and the surface of weldment will be more smooth when using helium as the shielding gas than when using the argon as the shielding gas moreover, consequently the utility model discloses in adopt the argon as the shielding gas.
The protective gas is required to be emitted to the surface of a workpiece to be welded at a certain pressure through a nozzle opening, and researches show that if the flow rate of the protective gas is too small and the air flow stiffness is poor, the capability of removing ambient air is relatively weak, the protective gas can be deviated and scattered by slight lateral wind, and the protective effect is poor. On the contrary, if the protective gas is put into the furnace with too large flow, the laminar flow of the ejected gas flow is very thin, and turbulent flow is easily formed, so that the atmosphere is involved in the molten pool to form air holes, and the welding quality is reduced.
Preferably, in the utility model discloses in, the protective gas flow is 5 ~ 35L/min, and further preferred is 10 ~ 15L/min, and more preferred is 12-14L/min.
After the welding parameters are set, preferably, the tube plate 2 expanded with the heat exchange tube 1 is placed on a workbench for accurate positioning, the heat exchange tube is ensured to be vertically placed in the axial direction, and a laser welding gun positions and welds the heat exchange tube to be welded from the upper part of a workpiece, as shown in fig. 1.
Examples
Example 1
Connecting a heat exchange tube and a tube plate of the AP1000 steam generator, wherein the tube plate is made of an SA-508Gr.3Cl.2 forge piece, a 690 nickel-based surfacing layer with the thickness of 6.6mm is overlaid on one side of the tube plate, the heat exchange tube is made of SA-163UNS N06690, the joint of the heat exchange tube and the tube plate is in an even mode, the assembly error delta h between the heat exchange tube and the tube plate is +/-0.13 mm, and the welding mode adopts a laser welding machine to carry out self-melting welding.
When welding is performed:
1) a wiping rod with a white cloth wrapping the top end of the wiping rod and free of hair falling is used for dipping acetone to wipe the surfaces of the pipe hole and the pipe plate, and the pipe hole and the surface of the pipe plate are strictly cleaned until the pipe hole and the surface of the pipe plate are wiped by the acetone without color change, so that the cleaning quality is ensured.
2) Selecting a positioning expansion head matched with the heat exchange tube according to the size of the heat exchange tube, adjusting the heat exchange tube to be flush with the surface of the tube plate, inserting the positioning expansion head into the heat exchange tube, enabling a rear end connecting seat of the positioning expansion head to tightly abut against the surface of the primary side of the tube plate, pressing an expansion gun starting switch, observing the indication of an operation panel indicating lamp in the expansion joint process, loosening the switch after confirming that the expansion joint is completed, and pulling out the expansion gun. During the process of pulling out the expansion gun, attention is paid to keeping the expansion gun horizontal so as to ensure that the central line of the core shaft of the expansion gun is collinear with the axis of the pipe hole. And finally, after the expansion joint is finished, checking the expansion joint effect by using a plug gauge.
3) The laser welding machine is installed and debugged, so that the correct connection and normal functions of all lines are ensured, and the welding gas and the like meet the requirements.
The welding parameters of the laser welding machine are set as follows:
the welding energy is selected to be 600W, the welding speed is 1m/min, the protective gas is argon with the purity of more than or equal to 99.997 percent, the gas flow is 12L/min, and the diameter of a light spot is about 0.7 mm.
And then, a workpiece to be welded is placed on the workbench to be accurately positioned, the heat exchange tube is ensured to be vertically placed in the axial direction, and the laser welding gun is used for positioning and welding the heat exchange tube to be welded from the upper part of the workpiece.
The detection results of the welded joint after welding are as follows:
the weld penetration is 1.5 mm;
the minimum leakage path is 1.2 mm.
Visual detection: the weld joint is attractive in appearance, welding defects visible to naked eyes do not exist, a plug gauge is adopted for size detection after welding, the inner diameter of the weld joint is detected to be larger than or equal to phi 15.46mm, and the size requirement of corresponding products is met.
Liquid permeation: and PT inspection is carried out according to the corresponding product requirements to be qualified.
Metallographic test: the minimum leakage channel meets the requirements through metallographic examination, and no defects such as cracks, pores and the like are displayed.
The present invention has been described above in connection with preferred embodiments, which are merely exemplary and illustrative. On this basis, can be right the utility model discloses carry out multiple replacement and improvement, these all fall into the utility model discloses a protection scope.

Claims (8)

1. The utility model provides a connected system of heat exchange tube and tube sheet which characterized in that: the connecting system comprises a heat exchange tube (1), a tube plate (2), a positioning expansion joint device and an automatic laser welding machine;
a nickel-based surfacing layer (21) is surfacing welded on the surface of the primary side of the tube plate (2), and the assembling form of the heat exchange tube (1) and the tube plate (2) is flat;
the automatic laser welding machine comprises a workbench (10), a laser welding gun (3), a laser generator (4) and a shielding gas device (9);
the positioning expansion joint equipment comprises an expansion gun (11), a positioning expansion head and a plug gauge;
the positioning expansion head comprises an expansion rod (81), a front end nut (82), a rear end connecting seat (83), a split ring (84) and a rubber ring (85);
the rubber circle (85) includes I type rubber circle (851) and II type rubber circle (852), and I type rubber circle (851) is including a plurality of, and I type rubber circle (851) sets up the both sides at II type rubber circle (852).
2. The connection system according to claim 1, wherein: the automatic laser welding machine further comprises a power supply control device (5), a cooler (6) and an operation panel (7).
3. The connection system according to claim 1, wherein: one end of the expansion rod (81) is connected with the rear end connecting seat (83) through a unthreaded hole, wherein an external thread is arranged on the rear end connecting seat (83), the rear end connecting seat (83) is used for being in threaded connection with the expansion gun (11), and the expansion rod (81) can be driven to move through the expansion gun (11); the other end of the expanding rod (81) is connected with a front end nut (82) through a threaded hole, wherein the front end nut (82) can move under the driving of the expanding rod (81) and is used for extruding the rubber ring (85).
4. The connection system according to claim 3, wherein: the split ring (84) is sleeved on the expansion rod (81) and fixedly connected with the rear end connecting seat (83).
5. The connection system according to claim 1, wherein: the rubber ring (85) is sleeved on the expansion rod (81) and is positioned between the front end nut (82) and the split ring (84).
6. The connection system according to claim 1, wherein: the hardness of the I-type rubber ring (851) is greater than that of the II-type rubber ring (852).
7. The connection system according to claim 1, wherein: the type II rubber ring (852) comprises a plurality of rubber rings.
8. The connection system according to claim 7, wherein: the rubber ring (85) comprises 2I-shaped rubber rings (851) and 2 II-shaped rubber rings (852), and the rubber rings are arranged on the expansion rod (81) according to the sequence of the I-shaped rubber rings (851), the II-shaped rubber rings (852) and the I-shaped rubber rings (851).
CN201922472881.8U 2019-12-31 2019-12-31 Connecting system of heat exchange tube and tube plate Active CN212144963U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201922472881.8U CN212144963U (en) 2019-12-31 2019-12-31 Connecting system of heat exchange tube and tube plate

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201922472881.8U CN212144963U (en) 2019-12-31 2019-12-31 Connecting system of heat exchange tube and tube plate

Publications (1)

Publication Number Publication Date
CN212144963U true CN212144963U (en) 2020-12-15

Family

ID=73708555

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201922472881.8U Active CN212144963U (en) 2019-12-31 2019-12-31 Connecting system of heat exchange tube and tube plate

Country Status (1)

Country Link
CN (1) CN212144963U (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114211120A (en) * 2021-12-31 2022-03-22 中核武汉核电运行技术股份有限公司 Steam generator tube-tube plate joint, welding device and welding process

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114211120A (en) * 2021-12-31 2022-03-22 中核武汉核电运行技术股份有限公司 Steam generator tube-tube plate joint, welding device and welding process
CN114211120B (en) * 2021-12-31 2024-01-12 中核武汉核电运行技术股份有限公司 Tube-tube plate joint of steam generator for pressurized water reactor nuclear power station

Similar Documents

Publication Publication Date Title
CN105081538B (en) Process for automatically welding small-specification thin-walled tube and small-holed axle tube plate
JP5602458B2 (en) Method for joining two metal parts by a tungsten-inert gas welding method and apparatus for carrying out the method
US5719369A (en) Stress corrosion crack repair by plasma arc welding underwater welding
CN102941397B (en) Argon tungsten arc welding method for nickel-based alloy
US5710405A (en) Method for developing residual compressive stress in stainless steel and nickel base superalloys
JP3735135B2 (en) Method for joining metal parts by fusion arc welding
CN105252117B (en) A kind of nickel alloy process pipe Manual argon-arc welding
CN107052517B (en) Automatic butt welding process for low-alloy steel and nickel-based alloy dissimilar steel heat exchange tubes
CN112658443B (en) Manual argon tungsten-arc welding process method for steel-aluminum connector
CN103212913B (en) A kind of group of large diameter thin wall corrugated stainless steel tubing to and welding method
CN111069775B (en) Connecting system and method for heat exchange tube and tube plate
CN106944723A (en) A kind of low-alloy steel heat exchanger tube docking automatic soldering technique for filling melting ring
CN102814575A (en) Deep-groove narrow-gap manual argon arc sealing welding method
CN112171016B (en) Austenitic stainless steel NBG welding process
CN112894087B (en) Tube plate nickel-based alloy double-tungsten-electrode single-hot-wire automatic tungsten electrode argon arc welding surfacing process
CN102744499B (en) Double-side double-arc welding process for root layer of pipeline
CN106975826A (en) A kind of nickel-base alloy heat exchanger tube docks automatic soldering technique
CN105665898A (en) Automatic submerged arc welding method for pearlitic heat-resistant steel composite board
CN106695079A (en) Welding method of double-metal composite pipe
CN108817620A (en) The welding method of stainless sheet steel
CN212144963U (en) Connecting system of heat exchange tube and tube plate
CN107052536B (en) Automatic butt welding process for low alloy steel heat exchange tubes without filler
CN110508909B (en) Welding system and method for stainless steel pipe butt joint automatic superposition pulse single-pass welding
CN111037065A (en) Welding method for inner hole welding of tube plate of small-aperture heat exchange tube
CN114160931A (en) Welding method of copper tube and brass flange

Legal Events

Date Code Title Description
GR01 Patent grant
GR01 Patent grant