Connecting pipe forming method for integrated connecting pipe section of large-diameter barrel forge piece with side connecting pipe

Abstract

The invention discloses a connecting pipe forming method for an integrated connecting pipe section of a large-diameter barrel forge piece with a side connecting pipe, and belongs to the technical field of forging. The problem that the production efficiency of the large-diameter barrel forge piece with the side connecting pipe is low due to limitation of the space size of a pressing machine is solved. The forming method comprises the following steps: step 1, preparing a blank; 2, locally heating the forming part of the connecting pipe; 3, the cross beam and the flanging punch assembly are installed on a hydraulic press; 4, the lower supporting die is placed at a designated position, and the supporting cylinder is placed in the lower supporting die; 5, centering the to-be-flanged connecting pipes of the two cylinder blanks and placing the to-be-flanged connecting pipes in the lower supporting die; sixthly, the hydraulic press is pressed downwards, and flanging forming of one connecting pipe of each of the two barrel blank forgings is completed; and 7, the step 2 to the step 6 are repeated, and the connecting pipe flanging operation of the other connecting pipe of the barrel blank forge piece is completed. According to the device, two barrel forging blanks with side connecting pipes can be subjected to connecting pipe flanging forming at the same time outside a pressing machine, and the production efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of forging, in particular to a method for forming an integrated pipe section of a large-diameter barrel forging with a side pipe. Background Art

[0002] The pipe section is one of the key components of nuclear reactor pressure vessel equipment. In the prior art, the pipe section forging is assembled with the inlet / outlet pipe by welding. With the extension of the design life and the improvement of the safety level of new nuclear reactors, the quality requirements for internal parts are becoming more and more stringent, which requires the design and manufacturing of forgings such as pipe sections to develop in the direction of integration and no welds.

[0003] With the continuous development of the nuclear power industry, the requirements for nuclear power equipment are getting higher and higher, and gradually tend to be integrated. When the existing large cylinders with side pipes are produced by flanging integrated molding methods, they are limited by the working space of the press, and their efficiency is low and the production cost is high. Summary of the invention

[0004] In view of the above analysis, the present invention aims to provide an integrated pipe section pipe forming method for a large diameter cylinder forging with a side pipe, so as to solve the technical problem of low production efficiency due to the limitation of the space size of the press when flanging the pipe for large diameter cylinder forgings with side pipes.

[0005] The purpose of the present invention is mainly achieved through the following technical solutions:

[0006] The present invention provides a method for forming an integrated pipe section of a large-diameter pipe barrel forging with a side pipe, the forming method comprising the following steps:

[0007] Step 1, preparing a forging blank of a barrel with a side pipe to be flanging;

[0008] Step 2: Use a local heating device to locally heat the tube forming part;

[0009] Step 3, assemble the crossbeam and the flanging punch assembly and connect them to the hydraulic press;

[0010] Step 31, the crossbeam penetrates the working space formed by the columns of the hydraulic press, and the middle position of the crossbeam is fixedly connected to the hydraulic press; both ends of the crossbeam are located outside the hydraulic press;

[0011] Step 32, installing the flanging punch assemblies at both ends of the beam respectively;

[0012] Step 4: Place the supporting lower die at the measured designated position, and place the supporting cylinder inside the supporting lower die;

[0013] Step 5, align the two tubes to be flanged of the barrel blanks and place them in the supporting lower die;

[0014] Step 6: The hydraulic press presses downward to complete the flanging of one pipe of each of the two barrel blank forgings;

[0015] Step 7: Repeat steps 2 to 6 to complete the pipe flanging operation of another pipe of the barrel blank forging.

[0016] Furthermore, in step 1, the process of preparing the forged barrel blank with side pipe to be flanging is: prefabricating two barrel blanks with bosses on the outside, and processing conical pipe forming guide holes at the corresponding positions of the pipes on the inner walls of the barrel blanks to obtain the forged barrel blank with side pipe to be flanging.

[0017] Furthermore, in step 2, when the local heating device is used to locally heat the tube forming part, the heating process is divided into three stages.

[0018] Furthermore, in step 2, the first stage is heated to 300-350°C and kept warm for 3-5 hours; the second stage is heated to 650°C-700°C and kept warm for 4-6 hours.

[0019] Further, in step 2, the third stage is heating to 980°C-1020°C for 6-8 hours.

[0020] Further, in step 32; the flanging punch assembly includes a connecting plate and a forming punch;

[0021] The forming punch is arranged below the connecting plate, and the two are detachably connected; one side of the connecting plate is detachably connected to one end of the corresponding crossbeam.

[0022] Further, in step 33, both ends of the crossbeam are provided with assembly grooves;

[0023] A connecting protrusion is provided on one side of the connecting plate adjacent to the cross beam, and the connecting protrusion can be embedded in the corresponding assembly groove.

[0024] Furthermore, in step 5, before pressing down, the flanging punch assemblies arranged at both ends of the crossbeam are respectively placed inside the corresponding cylinder blank, and the forming punch is located directly above the tapered pipe forming guide hole of the cylinder forging blank with side pipe to be flanging.

[0025] Further, in step 6, the measuring range of the hydraulic press is 4000-8000 mm; and the pressing speed is 8-12 mm / s.

[0026] Furthermore, in step 7, after the flanging forming of one of the pipes of the barrel forging blank with side pipes is completed, the two barrel forging blanks with side pipes are simultaneously rotated by the operating machine so that the tapered pipe forming guide hole of the other pipe is aligned with the corresponding forming punch; steps 2 to 6 are repeated until the flanging forming of all pipe forming parts is completed.

[0027] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0028] (1) The forming method of the present invention can realize the flanging extrusion forming of a large-diameter cylinder forging with a side pipe in steps, and transmit the force of the hydraulic press to the flanging forming assembly outside the crossbeam through the crossbeam, so as to realize the flanging extrusion forming of the cylinder blank outside the hydraulic press, thereby effectively solving the problem of limited space size of the press.

[0029] (2) The present invention can simultaneously perform pipe flanging forming on two large-diameter cylindrical forgings with side pipes outside a press, thereby improving production efficiency and reducing production costs.

[0030] (3) The present invention can effectively perform pipe flanging on cylinder forgings with an inner diameter ranging from φ2000 mm to φ10000 mm, thereby realizing integrated contour forging of cylinder forgings with side pipes.

[0031] In the present invention, the above-mentioned technical solutions can also be combined with each other to achieve more preferred combination solutions. Other features and advantages of the present invention will be described in the subsequent description, and some advantages can become obvious from the description, or can be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the embodiments of the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The drawings are only for the purpose of illustrating specific embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings.

[0033] Figure 1 It is a schematic diagram of a forging blank of a barrel with a side pipe to be flanging according to the present invention;

[0034] Figure 2 is a front view of the crossbeam of the present invention;

[0035] Figure 3 A top view of the crossbeam of the present invention;

[0036] Figure 4 The structure of the flanging punch assembly of the present invention is shown in FIG. Figure 1 ;

[0037] Figure 5The structure of the flanging punch assembly of the present invention is shown in FIG. Figure 2

[0038] Figure 6 A supporting lower mold assembly of the present invention;

[0039] Figure 7 Schematic diagram of the pipe flanging extrusion forming process of the present invention Figure 1 ;

[0040] Figure 8 Schematic diagram of the pipe flanging extrusion forming process of the present invention Figure 2 ;

[0041] Fig. 9 The forged cylinder body with side pipe after flanging of the present invention;

[0042] Fig.10 It is a schematic diagram of the external forming process of the tube body forging with side tube of the present invention;

[0043] Fig.11 It is a schematic diagram of the overall assembly of the local heating device of the present invention;

[0044] Fig.12 It is a schematic diagram of the assembly of the heating device in the local heating device of the present invention;

[0045] Fig.13 It is a schematic diagram of the supporting structure in the local heating device of the present invention;

[0046] Fig.14 It is a schematic diagram of the structure of the heat preservation cover in the local heating device of the present invention;

[0047] Fig.15 A top view of a circular furnace body in a local heating device of the present invention.

[0048] Reference numerals:

[0049] 1- Forging blank of barrel with side pipe to be flanging; 101- Guide hole for forming conical pipe; 2- Crossbeam; 201- Assembly groove; 202- First vertical pin hole; 203- Isosceles trapezoidal part; 204- Rectangular part; 3- Flanging punch assembly; 301- Connecting plate; 302- Upper cross pin; 303- Connecting vertical pin; 304- Lower cross pin; 305- Forming punch; 306- Connecting convex block; 307- Second vertical pin hole; 308- Vertical pin hole; 4- Support lower die assembly; 401- Support lower die; 402- Support cylinder; 5- Hydraulic press; 6- Forging barrel with side pipe after flanging; 7- Heating equipment; 8- Support structure; 9- Insulation cover; 10- Insulation layer in circular furnace body; 11- Heating control device; 12- Circular furnace body; 13- Thermocouple; 14- Combustion nozzle; 15- Gas pipeline; 16-air pipeline; 17-movable lifting platform; 18-first positioning groove; 19-second positioning groove; 21-bottom plate; 22-rotating motor; 23-first track; 24-second track; 25-third track 25; 26-fourth track; 27-active support rotating roller; 28-first passive support rotating roller; 29-second passive support rotating roller; 30-third passive support rotating roller; 31-first bracket; 32-second bracket; 33-third bracket; 34-fourth bracket; 35-first bearing; 36-second bearing; 37-third bearing; 38-fourth bearing; 39-fifth bearing; 40-sixth bearing; 41-seventh bearing; 42-eighth bearing; 43-insulation layer of the inner cavity of the insulation cover; 44-first positioning block; 45-second positioning block. DETAILED DESCRIPTION

[0050] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0051] The present invention provides a method for forming an integrated pipe section of a large diameter pipe barrel forging with a side pipe, such as Fig.10 As shown, the forming method is used to realize the flanging extrusion forming of a large-diameter barrel forging with a side pipe in steps, and the specific steps are as follows:

[0052] Step 1, preparing a forging blank 1 of a barrel with a side pipe to be flanging;

[0053] In the above step 1, two cylindrical blanks with bosses on the outer sides are prefabricated, and tapered pipe forming guide holes 101 are machined at positions corresponding to the pipes on the inner walls of the cylindrical blanks;

[0054] Step 2: Use local heating equipment to locally heat the tube forming part; specifically, the following process is included:

[0055] Step 21, install local heating equipment and position the large-diameter barrel forging with side pipe to be flanging;

[0056] Step 22, start the heating device to heat the cylinder according to the characteristics of the heating stage;

[0057] The characteristics of the heating stage are as follows: the heating process is divided into three stages. The first stage is heating to 300-350℃ and keeping warm for 3-5h, the second stage is heating to 650℃-700℃ and keeping warm for 4-6h, and the third stage is heating to 980℃-1020℃ and keeping warm for 6-8h. The heating condition of the cylinder is monitored in real time by thermocouples.

[0058] Step 23, after heating is completed, the local heating device is disassembled to complete the local heating of the tube forming part.

[0059] Step 3, assembling the crossbeam 2 and the flanging punch assembly 3 and connecting them to the hydraulic press 5; specifically comprising the following sub-steps:

[0060] Step 31, fixedly connecting the crossbeam 2 to the hydraulic press 5;

[0061] Step 32, assembling the flanging punch assembly 3;

[0062] First, insert the connecting vertical pin 303 into the vertical pin hole 308 through the handle ring, and insert the upper horizontal pin 302 into the upper horizontal pin 302 hole at the top of the connecting vertical pin 303; the bottom of the connecting vertical pin 303 is embedded in the vertical pin groove, and the lower horizontal pin 304 hole on the connecting vertical pin 303 is aligned with the first horizontal pin hole on the first end of the cylindrical part, and then, the lower horizontal pin 304 is inserted to complete the assembly of the connecting plate 301 and the forming punch 305.

[0063] Step 32, assembling the flanging punch assemblies 3 at both ends of the beam 2;

[0064] First, the connecting protrusion 306 is embedded in the corresponding assembly groove 201, and the second vertical pin hole 307 is aligned with the first vertical pin hole 202. At this time, the first connecting pin is inserted into the first vertical pin hole 202 and the second vertical pin hole 307 to complete the assembly of the connecting plate 301 and the beam 2;

[0065] Step 4, placing the supporting lower mold 401 at the measured designated position, and placing the supporting cylinder 402 inside the supporting lower mold 401;

[0066] Step 5, align the pipes of two barrel forging blanks 1 with side pipes to be flanging and place them in the supporting lower die 401;

[0067] In the above step 5, the flanging punch assemblies 3 at both ends of the crossbeam 2 are respectively placed inside the corresponding cylinder blank, and the forming punch 305 is located directly above the tapered pipe forming guide hole 101 of the cylinder forging blank 1 with side pipe to be flanging;

[0068] Step 6: The hydraulic press 5 is pressed down to complete the flanging of one pipe of each of the two barrel forging blanks 1 with side pipes to be flanging, such as Figure 7 and Figure 8 As shown;

[0069] In the above step 6, the measuring range of the hydraulic press 5 is 4000-8000 mm; the pressing speed is 8-12 mm / s;

[0070] Step 7, repeat step 2, step 4 to step 6, complete the pipe flanging operation of another pipe of the barrel blank forging, and obtain the barrel forging 6 with side pipe after flanging. Fig. 9 shown.

[0071] In the above step 7, after the flanging forming of one of the tubes of the barrel forging blank with side tube is completed, the two barrel forging blanks with side tubes are rotated simultaneously by the operating machine so that the tapered tube forming guide hole 101 of the other tube is aligned with the corresponding forming punch 305; repeat step 2, and use the local heating equipment to locally heat the tube forming part; then, repeat steps 4 to 6 until the flanging forming of the tube forming part is completed.

[0072] It should be noted that if the blank is locked in step 6, then in step 7, steps 2 to 6 are repeated.

[0073] Compared with the prior art, the present invention adopts the above-mentioned forming method to realize the flanging extrusion forming of large-diameter cylinder forgings with side pipes in steps, and transmits the force of the hydraulic press 5 to the flanging forming assembly outside the crossbeam 2 through the crossbeam 2, so as to realize the flanging extrusion forming of the cylinder blank outside the hydraulic press 5, thereby effectively solving the problem of limited space size of the press.

[0074] It should be noted that the above-mentioned large-diameter tube forging with side tube forging integrated tube section tube forming method of the present invention adopts the following forming tooling for forming; Figure 2-6 As shown, the forming tooling includes a hydraulic press 5, a crossbeam 2 and two sets of flanging punch assemblies 3 with the same structure; the middle position of the crossbeam 2 is fixed on the hydraulic press 5, and both ends of the crossbeam 2 extend outward to the outside of the hydraulic press 5; the two sets of flanging punch assemblies 3 are correspondingly fixed on the two ends of the crossbeam 2; along the length direction of the crossbeam 2, both sides of the hydraulic press 5 are respectively provided with a cylindrical forging blank 1 with a side pipe to be flanging, as shown in FIG. Figure 1As shown; the two ends of the beam 2 together with the flanging punch assembly 3 are respectively located in the corresponding cylindrical forging with side pipes to perform flanging forming on them at the same time.

[0075] Specifically, the crossbeam 2 passes through the space formed by the four columns of the hydraulic press 5, and both ends of the crossbeam 2 are located outside the hydraulic press 5. Both ends of the crossbeam 2 are detachably connected with flanging punch assemblies 3. Correspondingly, cylindrical forging blanks with side pipes to be flanging are respectively provided on the outside of the hydraulic press 5. The flanging punch assemblies 3 are located in the corresponding cylindrical forging blanks with side pipes to be flanging 1. During flanging, the hydraulic press 5 drives the crossbeam 2 to move downward, and the flanging punch assemblies 3 arranged at both ends of the crossbeam 2 can simultaneously perform flanging on the corresponding cylindrical forging blanks with side pipes to be flanging 1.

[0076] In the prior art, the crossbeam 2, the punch assembly and the cylinder forging to be formed are all arranged in the space formed by the columns of the hydraulic press 5, and therefore are limited by the working space of the hydraulic press 5. Compared with the prior art, the crossbeam 2 of the present invention penetrates the working space formed by the columns of the hydraulic press 5, and the flanging punch assemblies 3 are arranged at both ends of the crossbeam 2 and are both located outside the hydraulic press 5. Therefore, when flanging the cylinder forging blank to be connected to the side pipe, it will not be limited by the space of the hydraulic press 5; in addition, by arranging the flanging punch assemblies 3 on both sides of the crossbeam 2, the present invention can simultaneously perform flanging on two groups of cylinder forging blanks to be connected to the side pipe, thereby improving the flanging efficiency and reducing the production cost.

[0077] It should be noted that the diameter of the cylindrical forging with side pipe of the present invention is 2000mm-10000mm, and it is particularly suitable for forming cylindrical forgings with a diameter of 6000mm-10000mm.

[0078] In the prior art, the existing hydraulic press 5 has four columns, and the gap between adjacent columns is 7000mm. The maximum lifting height of the existing hydraulic press 5 is 8000mm. Considering the pressing stroke of the beam 2 and the height of the forming auxiliary tool, the maximum outer diameter of the cylinder that can be flanged inside the press is 5000mm-5500mm.

[0079] Since the flanging punch assembly 3 of the present invention is arranged outside the hydraulic press 5, the flanging forming will not be limited by the hydraulic press 5 column and the maximum lifting height of the press (8000mm). Therefore, the forming tooling of the present invention can form a wider range of cylinder sizes.

[0080] It should be pointed out that a tube forming portion is provided on the forging blank of the barrel with side tube of the present invention, and a conical tube forming guide hole 101 is provided at the tube forming portion, and the conical tube forming guide hole 101 to be flanging is aligned with the forming punch 305 in the vertical direction; when the tube is formed at the tube forming portion, the hydraulic press 5 can generate a shear force on the crossbeam 2, and the crossbeam 2 will transmit the force to the flanging forming components at both ends after being subjected to the force. At this time, the flanging forming component is subjected to downward pressure, and the flanging forming component performs flanging on the conical tube forming guide hole 101 under this pressure; after flanging, the hydraulic press 5 drives the crossbeam 2 to lift, and at the same time, the crossbeam 2 drives the flanging forming components at both ends to lift, and the forming punch 305 in the flanging forming component disengages from the conical tube forming guide hole 101, and demolding is completed.

[0081] It should be noted that if Figure 2 and Figure 3 As shown, both ends of the crossbeam 2 of the present invention are provided with assembly grooves 201 and a plurality of first vertical pin holes 202 ; the first vertical pin holes 202 all penetrate the corresponding assembly grooves 201 .

[0082] Specifically, the crossbeam 2 of the present invention includes an isosceles trapezoidal portion 203 and a rectangular portion 204; wherein, the isosceles trapezoidal portion 203 is arranged on the top surface of the rectangular portion 204 along the length direction thereof, and the two are integrally formed; the length of the base side of the isosceles trapezoidal portion 203 is smaller than the length of the rectangular portion 204; along the length direction of the rectangular portion 204, assembly grooves 201 opening outward are arranged on both end surfaces of the rectangular portion 204; and first vertical pin holes 202 of corresponding positions and the same number are arranged above and below the assembly groove 201.

[0083] Compared with the prior art, the present invention utilizes the assembly grooves 201 and the first vertical pin holes 202 at both ends of the crossbeam 2 to achieve a detachable connection with the flanging punch assembly 3, thereby facilitating assembly and replacement of the flanging punch assembly 3.

[0084] Since the middle portion of the cross beam 2 is connected to the hydraulic press 5 , in order to withstand the pressure exerted by the hydraulic press 5 , the thickness of the middle portion of the cross beam 2 of the present invention is greater than the thickness of the two end portions thereof.

[0085] Specifically, when the hydraulic press 5 is pressing down, the shear force borne by the middle position of the beam 2 is greater than the force borne by the two ends. Therefore, the middle part is set to be relatively thick and the two ends are relatively thin, which can ensure that the beam 2 can normally transmit the force to the flanging punch assembly 3 and meet the requirements of normal operation.

[0086] When flanging the forging blank with side pipe cylinder to be flanging is carried out, in order to ensure that the end of the beam 2 together with the flanging punch assembly 3 can smoothly extend into the forging blank with side pipe cylinder from one end thereof, the width of the middle position of the beam 2 of the present invention is greater than the width of its two end portions; that is, the width of the two end portions of the beam 2 is smaller than the width of the middle position.

[0087] In order to perform flanging forming on the forged blank 1 of the barrel with side pipe to be flanging, as Figure 4 and Figure 5 As shown, the flanging punch assembly 3 of the present invention includes a connecting plate 301 and a forming punch 305; the forming punch 305 is arranged below the connecting plate 301, and the two are detachably connected; one side of the connecting plate 301 is detachably connected to one end of the corresponding beam 2.

[0088] Specifically, the connecting plate 301 of the present invention is a rectangular connecting plate 301, which is horizontally arranged and detachably connected to the forming punch 305 directly below it; one side of the rectangular connecting plate 301 is detachably connected to the beam 2 through the assembly groove 201.

[0089] Compared with the prior art, the present invention can firmly fix the forming punch 305 through the connecting plate 301; by setting the forming punch 305 and the connecting plate 301 in a detachable connection mode, it is convenient to assemble and replace the forming punches 305 of different sizes.

[0090] In order to ensure the connection strength between the cross beam 2 and the flanging punch assembly 3, and thus ensure that the cross beam 2 transmits the pressure applied by the hydraulic press 5 to the flanging punch assembly 3, as shown in FIG. Figure 5 As shown, a connecting protrusion 306 is provided on one side of the connecting plate 301 of the present invention adjacent to the crossbeam 2. The connecting protrusion 306 can be embedded in the corresponding assembly groove 201 on the crossbeam 2, and a second vertical pin hole 307 is provided on the connecting protrusion 306; the number of the second vertical pin holes 307 and the first vertical pin holes 202 are equal and the positions correspond; the first vertical pin hole 202 and the second vertical pin hole 307 are provided with a first connecting pin.

[0091] Specifically, the connecting protrusion 306 is a rectangular protrusion, and correspondingly, the assembly grooves 201 at both ends of the beam 2 are also rectangular; the size of the connecting protrusion 306 matches the size of the assembly groove 201; a second vertical pin hole 307 is provided on the connecting protrusion 306; when the connecting protrusion 306 is connected and fixed to the beam 2, the connecting protrusion 306 is first embedded in the assembly groove 201, and after embedding, the second vertical pin hole 307 is aligned with the first vertical pin hole 202. At this time, the first connecting pin is inserted into the first vertical pin hole 202 and the second vertical pin hole 307. At this point, the fixed connection between the flanging punch assembly 3 and the beam 2 is completed.

[0092] It should be pointed out that the number of the first vertical pin hole 202 and the second vertical pin hole 307 are both 3, so as to meet the connection strength requirement between the flanging punch assembly 3 and the crossbeam 2.

[0093] Compared with the prior art, the present invention embeds the connecting protrusions 306 into the assembly grooves 201 at both ends of the beam 2 and fixes them with the first connecting pin, thereby ensuring that the force applied by the hydraulic press 5 is transmitted to the flanging punch assembly 3, thereby enabling the forming punch 305 to flanging the side pipe barrel forging blank 1 to be flanging.

[0094] In order to facilitate demoulding of the forming punch 305 after flanging, Figure 4 As shown, the forming punch 305 of the present invention includes a columnar portion and a peach-shaped portion; wherein, the first end of the columnar portion is detachably connected to the connecting plate 301, and the second end of the columnar portion is connected to the peach-shaped portion; the diameter of the columnar portion is smaller than the maximum diameter of the peach-shaped portion; when flanging the tapered pipe forming guide hole 101 of the cylindrical forging with side pipe to be flanging, the hydraulic press 5 is used to drive the crossbeam 2 to press down, and the crossbeam 2 transfers the shear force received to the connecting plate 301, and the connecting plate 301 drives the forming punch 305 to flanging the tapered pipe of the cylindrical forging with side pipe to be flanging.

[0095] It should be noted that the diameter of the columnar portion is smaller than the maximum diameter of the peach-shaped portion. The peach-shaped portion is designed in a peach-shaped shape with a "big head and small body", which can facilitate the demoulding of the forming punch 305 after the forming of the pipe is completed.

[0096] It should be noted that a vertical pin hole 308 is provided on the connecting plate 301 of the present invention; the vertical pin hole 308 penetrates the connecting plate 301 along the height direction of the connecting plate 301, and a connecting vertical pin 303 is provided in the vertical pin hole 308; the length of the connecting vertical pin 303 is greater than the height of the vertical pin hole 308; an upper cross pin 302 hole is provided on the top of the connecting vertical pin 303, and an upper cross pin 302 is provided in the upper cross pin 302 hole; a lower cross pin 304 hole is provided on the bottom of the connecting vertical pin 303; a lower cross pin 304 is provided in the lower cross pin 304 hole; the connecting plate 301 is detachably connected to the forming punch 305 through the lower cross pin 304.

[0097] Specifically, a vertical pin groove is provided on the end face of the first end of the cylindrical portion of the forming punch 305; the opening direction of the vertical pin groove is upward, that is, toward the direction of the connecting plate 301; a first transverse pin hole is provided on the first end of the cylindrical portion, and the first transverse pin hole passes through the above-mentioned vertical pin groove; the length of the connecting vertical pin 303 is greater than the height of the vertical pin hole 308, that is, both ends of the connecting vertical pin 303 can extend out of the vertical pin hole 308; the top of the connecting vertical pin 303 is fixed by inserting the upper transverse pin 302 into the hole of the upper transverse pin 302, and the bottom of the connecting vertical pin 303 is embedded in the vertical pin groove, and the lower transverse pin 304 hole thereon is aligned with the first transverse pin hole on the second end of the cylindrical portion. After inserting the lower transverse pin 304, the connecting plate 301 and the forming punch 305 are detachably connected.

[0098] Compared with the prior art, the present invention detachably connects the forming punch 305 through the connecting vertical pin 303. When the forming punch 305 is stuck with the blank, the lower horizontal pin 304 can be quickly pulled out to complete the rapid separation of the forming punch 305 and the connecting plate 301, so that the forming punch 305 remains in the blank. After the blank is cooled, the punch can be removed.

[0099] In order to facilitate the installation of the connecting pin 303, a handle ring is provided on the top of the connecting pin 303 of the present invention.

[0100] It should be pointed out that if Figure 6 As shown, the forming tool of the present invention further includes a supporting lower die assembly 4, wherein the supporting lower die assembly 4 includes a cylindrical supporting lower die 401, and the supporting lower die 401 is used to support the barrel forging with side pipes, and the supporting lower die 401 can ensure the support position of the blank and the pipe size when the pipe is flanging. It should be noted that the supporting lower die 401 is different according to the size of the barrel forging blank 1 with side pipes to be flanging.

[0101] like Figure 6 As shown, the supporting lower die assembly 4 of the present invention also includes a supporting cylinder 402 with a step inside; the supporting cylinder 402 is sleeved inside the supporting lower die 401; the outer wall of the supporting cylinder 402 is close to the inner wall of the supporting lower die 401; the supporting cylinder 402 is in the shape of a cylinder; it should be pointed out that after the tapered tube forming guide hole 101 of the forging blank with the side tube barrel is flanging, its end is in the shape of a step and follows the shape of the step of the inner wall of the supporting cylinder 402. If the supporting cylinder 402 is not provided, the end of the billet tube after flanging is wavy and uneven; after the supporting cylinder 402 is provided, the supporting cylinder 402 can back-extrude the high point of the tube of the billet during flanging to make the end of the tube flat; therefore, the flanging forming accuracy can be guaranteed by providing the supporting cylinder 402.

[0102] In summary, the supporting lower die 401 of the present invention can ensure the accurate position of the barrel flanging; the supporting barrel 402 of the present invention can ensure the forming accuracy of the pipe through the back extrusion effect during the pipe flanging process.

[0103] It should be pointed out that the connecting plate 301, various connecting pins and the forming punch 305 in the flanging punch assembly 3 of the present invention can be replaced with different sizes, so as to realize flanging forming of cylinders with different diameters.

[0104] Example 1

[0105] The integrated nozzle section of a nuclear reactor pressure vessel has an outer diameter of 5210mm, an inner diameter of 3950mm, and a distance from the nozzle end face to the center of the cylinder of 3520mm.

[0106] Description of the tube forming process:

[0107] Step 1, prefabricate two cylinder blanks with bosses on the outside, and process a tapered pipe forming guide hole 101 at the position corresponding to the pipe on the inner wall of the cylinder blank;

[0108] Step 2: locally heat the tube forming part; wherein the heating temperature is 1000° C. and the heating time is 4 hours;

[0109] Step 3, assembling the crossbeam 2 and the flanging punch assembly 3 and connecting them to the hydraulic press 5; specifically comprising the following sub-steps:

[0110] Step 31, fixedly connecting the crossbeam 2 to the hydraulic press 5;

[0111] Step 32, assembling the flanging punch assemblies 3 at both ends of the beam 2;

[0112] First, the connecting protrusion 306 is embedded in the corresponding assembly groove 201, and the second vertical pin hole 307 is aligned with the first vertical pin hole 202. At this time, the first connecting pin is inserted into the first vertical pin hole 202 and the second vertical pin hole 307 to complete the assembly of the connecting plate 301 and the beam 2;

[0113] Step 33, assembling the flanging punch assembly 3;

[0114] First, insert the connecting vertical pin 303 into the vertical pin hole 308 through the handle ring, and insert the upper horizontal pin 302 into the upper horizontal pin 302 hole at the top of the connecting vertical pin 303; the bottom of the connecting vertical pin 303 is embedded in the vertical pin groove, and the lower horizontal pin 304 hole on the connecting vertical pin 303 is aligned with the first horizontal pin hole on the first end of the cylindrical part, and then, the lower horizontal pin 304 is inserted to complete the assembly of the connecting plate 301 and the forming punch 305.

[0115] Step 4, placing the supporting lower mold 401 at the measured designated position, and placing the supporting cylinder 402 inside the supporting lower mold 401;

[0116] Step 5, align the two tubes to be flanged of the barrel blanks and place them in the supporting lower die 401;

[0117] In the above step 5, the flanging punch assemblies 3 at both ends of the crossbeam 2 are respectively placed inside the corresponding cylinder blank, and the forming punch 305 is located directly above the tapered pipe forming guide hole 101 of the cylinder blank;

[0118] Step 6: The hydraulic press 5 is pressed down to complete the flanging of one pipe of each of the two barrel blank forgings;

[0119] In the above step 6, the measuring range of the hydraulic press 5 is 4000-8000 mm; the pressing speed is 10 mm / step.

[0120] Step 7, repeating steps 2 to 6 to complete the pipe flanging operation of another pipe of the barrel blank forging, and obtaining the barrel forging 6 with side pipe after flanging.

[0121] Example 2

[0122] This embodiment provides a method for locally heating the tube forming part; specifically, it includes the following process:

[0123] Step 1: Install the local heating equipment and position the large-diameter barrel forging with side pipe to be flanging;

[0124] Step 11, welding a first positioning block and a second positioning block on both sides of the flanging guide opening of the side tube of the cylinder, wherein the distance between the first positioning block and the second positioning block is consistent with the straight-line distance between the first positioning groove and the second positioning groove on the circular furnace body of the local heating device, and the first positioning block and the side tube are kept on the same generatrix;

[0125] Step 12: Adjust the spacing of the four supporting rotating rollers of the local heating device to the specified position according to the outer diameter of the cylinder, and hang the cylinder onto the rollers with the gate hook;

[0126] Specifically, the designated position means: the active supporting rotating roller 27 and the second passive supporting rotating roller 29 are located on the same horizontal plane, and the first passive supporting rotating roller 28 and the third passive supporting rotating roller 30 are located on the same horizontal plane; the spacing between the active supporting rotating roller 27 and the first passive supporting rotating roller 28 and the spacing between the second passive supporting rotating roller 29 and the third passive supporting rotating roller 30 are equal, both are L3, L3≤√2 / 2×D1, where D1 is the outer diameter of the cylinder; preferably, L3 is equal to √2 / 2×D1.

[0127] Step 13, rotating the motor to adjust the circumferential position of the cylinder until the first positioning block and the second positioning block are directly facing downward with the side pipe, and at the same time adjusting the position of the circular furnace body of the heating device until the positioning groove on the circular furnace body is completely matched with the positioning block on the cylinder;

[0128] Step 14: attach a thermocouple to the insulation layer of the circular furnace body to record the entire heating process and monitor whether the heating condition meets the conventional process requirements;

[0129] It should be noted that the two ends of the thermocouple are respectively connected to the cylinder and the thermocouple graduation table for real-time monitoring and recording of temperature changes.

[0130] Step 15: Place a heat preservation cover in the inner cavity of the cylinder, covering the position that needs to be heated;

[0131] Step 2, start the heating device to heat the cylinder according to the characteristics of the heating stage;

[0132] Specifically, the characteristics of the heating stage are as follows: the heating process is divided into three stages. The first stage is heating to 300-350℃ and keeping warm for 3-5h, the second stage is heating to 650℃-700℃ and keeping warm for 4-6h, and the third stage is heating to 980℃-1020℃ and keeping warm for 6-8h. The heating condition of the cylinder is monitored in real time by a thermocouple.

[0133] Thermocouple scale is used to monitor and record temperature changes in real time, and to adjust heating equipment for temperature control in real time; the heating temperature is mainly suitable for nuclear power and hydrogenation cylinder forgings, and the third stage of heating is the cylinder side pipe flanging heating. The insulation time of the cylinder side pipe flanging heating is determined according to the depth of the cylinder side pipe flanging guide hole. The insulation time = the depth of the cylinder side pipe flanging guide hole / 100, unit: h.

[0134] The local heating equipment starts heating from a low temperature of 300-350℃, which can make a good transition when heating the forging blank in a cold state. The second and third heating stages can make each position of the local heating area fully heated, ensuring that the cylinder is heated evenly where it needs to be turned over; the third stage of 980℃-1020℃ can prevent the grain structure from growing at too high a temperature, affecting the material properties at this position and the entire forging life.

[0135] Step 3: After heating is completed, remove the local heating equipment.

[0136] Place the cylinder on the lower die assembly of the flanging auxiliary tool that has been placed in advance, fix the cylinder, remove the insulation cover, and complete the heating of the tube forming part.

[0137] Example 3

[0138] The present invention provides a structural form for realizing the above-mentioned local heating, wherein, that is, this embodiment provides a local heating device capable of locally heating a forging blank of a barrel body with a side pipe to be flanging, and the local heating device used comprises a heating device 7, a supporting structure 8 and a heat preservation cover 9 assembled; Figures 11 to 15 As shown, the heating device 7 includes a circular furnace body 12, an air supply component connected to the inner cavity of the circular furnace body, and an adjustment component for adjusting the distance between the combustion nozzle of the air supply component and the part of the cylinder to be flanging; the air supply component of the heating device 7 includes a heating control device 11, a gas pipeline 15, an air pipeline 16 and a combustion nozzle 14 located at the jet end of the gas pipeline 15; the adjustment component of the heating device 7 includes a movable lifting platform 17, and the distance between the combustion nozzle 14 and the part of the cylinder to be flanging can be adjusted by the movable lifting platform 17.

[0139] First, before heating the tube forming part, the heating device 7 and the heating support structure 8 need to be assembled. The movable lifting platform 17 of the heating device 7 is directly placed on the bottom plate of the support structure 8. The relative distance between the heating device 7 and the support structure 8 is adjusted through the movable lifting platform 17, so that the combustion nozzle 14 in the heating device 7 is aligned with the tapered tube forming guide hole 101. After the loading is completed, the lifting platform is adjusted so that the distance between the combustion nozzle and the part to be flanging is between 100-300mm, so as to achieve close-range heating of the combustion nozzle and the part to be flanging of the cylinder; the thermal insulation cover 9 is placed in the inner cavity of the cylinder.

[0140] It should be noted that the local heating device is assembled from the heating device 7, the support structure 8 and the heat preservation cover 9, and the movable lifting platform of the heating device 7 is directly placed on the bottom plate of the support structure 8, directly contacting but not directly connected. It should be pointed out that the heat preservation cover 9 of the present invention has no connection with the heating device 7 and the support structure 8.

[0141] Specifically, the circular furnace body 12 includes a circular outer cavity, a circular inner cavity, a circular insulation layer and a positioning groove.

[0142] The supporting structure 8 includes a base plate 21, a driving assembly and a track assembly. The track assembly is arranged on the base plate, and the driving assembly is connected to the track assembly by bearings.

[0143] The driving assembly includes a rotating motor 22, an active supporting rotating roller 27, a first passive supporting rotating roller 28, a second passive supporting rotating roller 29, a third passive supporting rotating roller 30, a first bearing 35, a second bearing 36, a third bearing 37, a fourth bearing 38, a fifth bearing 39, a sixth bearing 40, a seventh bearing 41, and an eighth bearing 42.

[0144] The track assembly includes a first track 23 , a second track 24 , a third track 25 , a fourth track 26 , a first bracket 31 , a second bracket 32 ​​, a third bracket 33 , and a fourth bracket 34 .

[0145] The heat preservation cover 9 includes an inner cavity heat preservation layer 43 and an outer cover. The shape of the heat preservation cover port is designed to match the inner cavity structure of the cylinder. The shape of the heat preservation cover port matches the inner cavity structure of the cylinder to ensure that the inner cavity of the cylinder is tightly closed, thereby reducing heat loss and achieving a good heat preservation effect.

[0146] In the heating device 7, the heating control device 11 is connected to the circular inner cavity of the circular furnace body 12 through the gas pipeline 15 and the air pipeline 16, and the gas pipeline 15 and the air pipeline 16 are connected in parallel; one end of the gas pipeline 15 is connected to the heating control device 11, and the other end of the gas pipeline 15 is equipped with a combustion nozzle 14 and passes into the circular inner cavity of the circular furnace body 12; one end of the air pipeline 16 is connected to the heating control device 11, and the other end of the air pipeline 16 is connected to the circular inner cavity wall of the circular furnace body and is not inserted into the circular inner cavity; the movable lifting platform 17 is connected to the heating control device 11, and the other end of the air pipeline 16 is connected to the circular inner cavity wall of the circular furnace body and is not inserted into the circular inner cavity; It is connected to the outer wall of the outer cavity of the circular furnace body 12 through multiple telescopic rods; the inner wall of the outer cavity of the circular furnace body 12 is processed with a first positioning groove 18 and a second positioning groove 19, and the angle between the first positioning groove 18 and the second positioning groove 19 is 180°; the straight-line distance between the inner edges of the first positioning groove 18 and the second positioning groove 19 is L1, and there is a certain distance between the inner edges of the two positioning grooves and the insulation layer 10 of the circular furnace body, so the straight-line distance between the inner edges of the two positioning grooves is greater than the diameter of the inner cavity of the circular furnace body, and smaller than the diameter of the outer cavity of the circular furnace body.

[0147] In the supporting structure, the rotating motor 22 is connected to one end of the active supporting rotating roller 27 through the first bearing 35, and the end is also connected to the first bracket 31 through the first bearing 35; the other end of the active supporting rotating roller 27 is connected to the second bracket 32 ​​through the second bearing 36. One end of the first passive supporting rotating roller 28 is connected to the first bracket 31 through the third bearing 37, and the other end of the first passive supporting rotating roller 28 is connected to the second bracket 32 ​​through the fourth bearing 38. One end of the second passive supporting rotating roller 29 is connected to the third bracket 33 through the fifth bearing 39, and the other end of the second passive supporting rotating roller 29 is connected to the fourth bracket 34 through the sixth bearing 40. One end of the third passive support rotating roller 30 is connected to the third bracket 33 through the seventh bearing 41, and the other end of the third passive support rotating roller 30 is connected to the fourth bracket 34 through the eighth bearing 42; the first bracket 31, the second bracket 32, the third bracket 33, and the fourth bracket 34 are respectively embedded and installed on the first track 23, the second track 24, the third track 25, and the fourth track 26, and the four brackets can respectively drive the rotating rollers installed thereon to move up and down on the tracks, and during the movement, the active support rotating roller 27 and the second passive support rotating roller 29 are always kept on the same horizontal plane, and the first passive support rotating roller 28 and the third passive support rotating roller 30 are always kept on the same horizontal plane; the distance between the active support rotating roller 27 and the first passive support rotating roller 28 is L3, L3≤√2 / 2×D1, where D1 is the outer diameter of the cylinder.

[0148] It should be noted that the movable lifting platform 17 in the heating device is directly placed on the bottom plate 21 in the supporting structure.

[0149] In order to cooperate with the use of the local heating equipment of the present invention, the first positioning block 44 and the second positioning block 45 are welded on both sides of the cylinder forging 1 with the side pipe to be flanging on the side of the cylinder; a level meter is used to mark during welding to ensure that the position is on the same generatrix as the side pipe; the shapes of the first positioning block 44 and the second positioning block 45 are respectively matched with the shapes of the first positioning groove 18 and the second positioning groove 19, and the straight-line distance between the two positioning blocks is L2, which is equal to the straight-line distance L1 between the two positioning grooves on the circular furnace body, ensuring that during the heating process, the two positioning blocks can be completely matched with the two positioning grooves respectively. It should be noted that the first positioning groove 18, the second positioning groove 19 located on the circular furnace body of the local heating equipment and the first positioning block 44 and the second positioning block 45 located on the cylinder together constitute a positioning structure during the local heating process.

[0150] It should be noted that when the local heating device of the present invention is used to locally heat the flanged part of the cylinder, first, before heating the cylinder, a first positioning block 44 and a second positioning block 45 are respectively welded on both sides of the cylinder forging 1 with a side pipe to be flanged on the side of the cylinder, and at the same time, according to the assembly composition of the above-mentioned local heating device, the heating device 7 and the heating support structure 8 are assembled, and the movable lifting platform of the heating device 7 is directly placed on the bottom plate of the support structure 8; the distance between the four drag rollers in the support structure 8 is adjusted according to the outer diameter of the cylinder; the relative distance between the heating device 7 and the support structure 8 is adjusted by the movable lifting platform 17, so that the combustion nozzle 14 in the heating device 7 is aligned with the tapered pipe forming guide hole 101; the material is loaded after the adjustment, and after the loading is completed, the lifting platform is adjusted so that the distance between the combustion nozzle and the part to be flanged is between 100-300mm, so as to realize close heating of the combustion nozzle and the part to be flanged; the heat preservation cover 9 is placed in the inner cavity of the cylinder to realize heat preservation of the local position; after the above is completed, the heating device is started for local heating.

[0151] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for forming an integrated pipe section of a large-diameter barrel forging with a side pipe, characterized in that: The following steps are involved: Step 1, preparing a forging blank of a barrel with a side pipe to be flanging; Step 2: Use a local heating device to locally heat the tube forming part; Step 3, assemble the crossbeam and the flanging punch assembly and connect them to the hydraulic press; Step 31, the crossbeam penetrates the working space formed by the columns of the hydraulic press, and the middle position of the crossbeam is fixedly connected to the hydraulic press; both ends of the crossbeam are located outside the hydraulic press; Step 32, installing the flanging punch assembly at both ends of the beam respectively; Step 4: Place the supporting lower die at the measured designated position, and place the supporting cylinder inside the supporting lower die; Step 5, align the two tubes to be flanged of the barrel blanks and place them in the supporting lower die; Step 6: The hydraulic press presses downward to complete the flanging of one pipe of each of the two barrel blank forgings; Step 7: Repeat steps 2 to 6 to complete the pipe flanging operation of another pipe of the barrel blank forging.

2. The method for forming an integrated pipe section of a large diameter barrel forging with a side pipe according to claim 1, characterized in that: In step 1, the process of preparing the forged barrel blank with side pipe to be flanging is: prefabricating two barrel blanks with bosses on the outside, and processing conical pipe forming guide holes at the corresponding positions of the pipes on the inner walls of the barrel blanks to obtain the forged barrel blank with side pipe to be flanging.

3. The method for forming an integrated pipe section of a large diameter barrel forging with a side pipe according to claim 2, characterized in that: In step 2, when the local heating device is used to locally heat the tube forming part, the heating process is divided into three stages.

4. The method for forming an integrated pipe section of a large diameter barrel forging with a side pipe according to claim 3, characterized in that: In step 2, the first stage is heating to 300-350° C. and keeping the temperature for 3-5 hours; the second stage is heating to 650° C.-700° C. and keeping the temperature for 4-6 hours.

5. The method for forming an integrated pipe section of a large diameter barrel forging with a side pipe according to claim 4, characterized in that: In the step 2, the third stage is heating to 980°C-1020°C and keeping the temperature for 6-8h.

6. The method for forming an integrated pipe section of a large diameter barrel forging with a side pipe according to claim 5, characterized in that: In the step 32; the flanging punch assembly includes a connecting plate and a forming punch; The forming punch is arranged below the connecting plate, and the two are detachably connected; one side of the connecting plate is detachably connected to an end portion of the corresponding crossbeam.

7. The method for forming an integrated pipe section of a large diameter barrel forging with a side pipe according to claim 6, characterized in that: In the step 33, both ends of the beam are provided with assembly grooves; A connecting protrusion is provided on one side of the connecting plate adjacent to the cross beam, and the connecting protrusion can be embedded in the corresponding assembly groove.

8. The method for forming an integrated pipe section of a large diameter barrel forging with a side pipe according to claim 7, characterized in that: In step 5, before pressing down, the flanging punch assemblies arranged at both ends of the beam are respectively placed inside the corresponding cylinder blank, and the forming punch is located directly above the tapered pipe forming guide hole of the cylinder forging blank with side pipe to be flanging.

9. The method for forming an integrated pipe section of a large diameter barrel forging with a side pipe according to claim 1, characterized in that: In step 6, the measuring range of the hydraulic press is 4000-8000 mm; the pressing speed is 8-12 mm / s.

10. The method for forming an integrated pipe section of a large diameter barrel forging with a side pipe according to any one of claims 1 to 9, characterized in that: In step 7, after the flanging of one of the tubes of the barrel forging blank with side tubes is completed, the two barrel forging blanks with side tubes are simultaneously rotated by the operating machine so that the tapered tube forming guide hole of the other tube is aligned with the corresponding forming punch; then steps 2 to 6 are repeated until the flanging of all the tube forming parts is completed.

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