A method for eliminating welding defects in titanium alloy ingot welding box
By designing groove structure and turning processing technology in the smelting crucible of titanium alloy ingots and combining with the ring welding technology of vacuum plasma welding boxes, the problem of incompatibility of titanium alloy ingots is solved, and the connection strength and production efficiency are improved.
Patent Information
- Application Number
- CN202411962751.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-30
- Publication Date
- 2025-04-08
AI Technical Summary
During the production process of titanium alloy ingots, due to the limited power of the smelting crucible material and welding box in the vacuum consumable arc furnace, the gap between the head and tail end faces of the primary ingot is large, and the welding incompatibility is serious, which affects the connection strength and production efficiency.
By designing the groove structure in the smelting crucible, the bottom center of each primary ingot has a groove, and during the turning process, ensure that the turning thickness is less than or equal to the maximum depth of the groove, and avoid bottom bumps. Then ring welding is performed in the vacuum plasma welding box to ensure welding strength.
It effectively avoids the problem of welding incompatibility, improves the connection strength between multiple primary ingots, reduces production risks, and improves production efficiency.
Smart Images
Figure CN119772518A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of smelting, in particular to a method for eliminating welding defects in a titanium alloy ingot welding box. Background Art
[0002] At present, titanium alloys have the advantages of high specific strength, good high temperature performance, excellent corrosion resistance, etc., and are widely used in aviation, aerospace, medical, shipbuilding and other fields.
[0003] In the production process of titanium alloy ingots, vacuum consumable arc melting is usually used to melt the raw materials multiple times to obtain titanium alloy ingots. The process may include: pressing and welding the uniformly mixed raw materials into electrode blocks to make consumable electrodes, and then melting the consumable electrodes in a vacuum consumable arc furnace to obtain multiple primary ingots; then assembling and welding the multiple primary ingots head to tail in sequence, and remelting the assembled and welded multiple primary ingots with their heads facing down and their bottoms facing up in a vacuum consumable arc furnace to obtain secondary ingots, and turning around and remelting again if necessary.
[0004] In the above production process, since the material of the melting crucible in the vacuum consumable arc furnace includes red copper, the flatness of the crucible bottom pad of the melting crucible will decrease with the use time, resulting in a larger gap between the head and tail end faces of the primary ingot after assembly. At the same time, due to the limited power of the welding box, the welds of the multiple primary ingots after welding are very prone to welding mismatches, resulting in poor connection strength between the multiple primary ingots, which brings great safety and quality risks to the subsequent use of the ingots. Summary of the invention
[0005] In view of the shortcomings of the prior art, the present invention proposes a method for eliminating welding mismatches in a titanium alloy ingot welding box, thereby avoiding the situation in which welding mismatches easily occur at the weld seams of multiple primary ingots after plasma welding in a welding box, and ensuring the connection strength between multiple primary ingots.
[0006] To achieve the above object, the present invention adopts the following technical solutions:
[0007] The present invention provides a method for eliminating welding defects in a titanium alloy ingot welding box, the method comprising the following steps:
[0008] S1. Place m consumable electrodes in a smelting crucible for smelting to obtain m primary ingots, each of which has a groove at the bottom center; wherein m≥2;
[0009] S2, turning the ingot crown at the top of the primary ingot to make it smooth, and obtaining m top turned ingots;
[0010] S3, taking out m-1 top turning ingots from the m top turning ingots, and turning the bottom of each of the taken out top turning ingots to obtain a target turning ingot;
[0011] S4, assembling the m-1 target turning ingots and the remaining top turning ingot head to tail to obtain an assembled ingot; during the assembly process, the bottom of the remaining top turning ingot is a free end;
[0012] S5, placing the assembled ingots horizontally in a vacuum plasma welding box, and performing circumferential welding on the head and tail joints of the assembled ingots by using the vacuum plasma welding box to obtain a welded ingot.
[0013] Preferably, in S4, before assembling, the bottom outer edge and the top outer edge of the target turned ingot are chamfered, and the top outer edge of the remaining top turned ingot is chamfered.
[0014] Preferably, the groove is truncated cone-shaped and coaxial with the primary ingot, and the diameter of the groove opening is larger than the diameter of the groove bottom.
[0015] Preferably, in S1, the depth of the groove is 5 to 20 mm.
[0016] Preferably, in S3, the turning thickness is less than or equal to the maximum depth of the groove, and the bottom of the top turning ingot is turned at a rotation speed of 5 to 20 rpm and a feed rate of 0.2 to 0.5 mm / rev.
[0017] Preferably, in S1, the smelting crucible comprises a cylinder, the lower end of the cylinder is sealedly connected to the bottom gasket through a connecting piece, and the upper end of the bottom gasket is provided with a boss matching the groove.
[0018] Preferably, the size of the chamfers on the target turned ingot and the remaining top turned ingot is 20 mm x 45°.
[0019] Preferably, in S5, the welding current of the ring welding is 300-550A, and the welding voltage is 45-80V.
[0020] Preferably, the ratio of the diameter of the groove notch to the outer diameter of the primary ingot is 0.15 to 0.75.
[0021] Preferably, the bottom surface of the groove is a plane or a curved surface recessed toward the top of the primary ingot.
[0022] Compared with the prior art, the present invention has the following beneficial effects:
[0023] The present invention places a plurality of consumable electrodes in a smelting crucible to smelt a primary ingot with a groove, then assembles the multiple primary ingots after turning the tops and bottoms, and welds the assembled ingots in a plasma welding box. Since the bottom of each primary ingot has a groove, and the turning thickness of the bottom of the primary ingot is less than or equal to the maximum depth of the groove, the smelting process and the turning process can be coordinated to avoid the bottom of the target turned ingot having a protrusion, thereby reducing the width of the head and tail joints in the assembled ingots, eliminating the problem of welding mismatch in the titanium alloy ingot welding box, thereby reducing the welding difficulty, improving production efficiency, and reducing production risks. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Figure 1 It is a schematic diagram of the structure of a melting crucible;
[0025] Figure 2 It is a bottom morphology diagram of a primary ingot produced by the production process described in the background art;
[0026] Figure 3 It is a flow chart of a method for eliminating welding defects in a titanium alloy ingot welding box according to the present invention;
[0027] Figure 4 It is a structural schematic diagram of the bottom pad of the smelting crucible of the present invention;
[0028] Figure 5 yes Figure 4 Schematic diagram of the cross-sectional structure along the A1-A2 position;
[0029] Figure 6 It is a schematic diagram of the bottom structure of the primary ingot of the present invention;
[0030] Figure 7 yes Figure 6 Schematic diagram of the cross-sectional structure along the B1-B2 position;
[0031] Figure 8 It is a bottom morphology diagram of a primary ingot produced by the present invention;
[0032] Fig. 9 It is a schematic structural diagram of a groove bottom surface of a primary ingot casting of the present invention being a curved surface;
[0033] Fig.10 It is a schematic diagram of the structure of the assembled ingot of the present invention;
[0034] Fig.11 It is the bottom morphology image of the target turned ingot of the present invention. DETAILED DESCRIPTION
[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0036] The vacuum consumable arc furnace is a type of vacuum metallurgical smelting equipment. The furnace body is a closed container, which is evacuated or filled with inert gas. After the electrodes introduced from the top of the furnace and the water-cooled crystallizer at the bottom of the furnace are energized and arc is struck, an arc is generated, and the metal or alloy is melted by the heat of the arc and solidified in the crystallizer. The electrode is made of the smelted metal, which is called a "consumable electrode vacuum arc furnace". Please refer to Figure 1 , Figure 1 This is a structural diagram of a melting crucible. The melting crucible is a mold used in the vacuum consumable arc melting process. The melting crucible includes a cylinder and a bottom pad. The lower end of the cylinder is sealed and connected to the bottom pad through a connector, and is used to form ingots of different specifications. The bottom pad not only plays a conductive role, but also plays a cooling, load-bearing, and sealing role. Therefore, the crucible bottom pad has good electrical conductivity, thermal conductivity, strength, and sealing properties.
[0037] Vacuum plasma welding box is a kind of equipment used for welding in vacuum or inert atmosphere. It can use the high temperature and high energy characteristics of plasma to achieve material welding. In other words, vacuum plasma welding uses plasma, which has the characteristics of high energy and high efficiency, and can complete the welding task in a short time, thus improving production efficiency.
[0038] Since the bottom pad needs to have good electrical and thermal conductivity, the material of the bottom pad currently usually includes red copper, and the thickness of the crucible bottom pad is between 50 and 100 mm, which makes the strength of the crucible bottom pad relatively low. After the crucible bottom pad has been used for many times, the middle area of the crucible bottom pad lacks supporting force, so that the middle area of the crucible bottom pad appears to be concave toward the ground, thereby reducing the flatness of the crucible bottom pad, resulting in a bulge on the bottom of the primary ingot formed by the smelting crucible.
[0039] Furthermore, usually, in order to realize the subsequent smelting furnace assembly, ingot chemical composition control and subsequent mechanical processing, it is necessary to use a lathe device to turn the top and bottom of the primary ingot to remove the ingot crown at the top of the primary ingot and make the bottom of the primary ingot smoother. However, in the process of turning the primary ingot, the lathe device drives the primary ingot to rotate by clamping the central area of both ends of the primary ingot, so that the turning tool can move horizontally in a direction perpendicular to the axis of rotation of the workpiece to turn the two ends of the primary ingot. In this way, it is difficult for the central area of both ends of the primary ingot to be cut smooth by the turning tool, such as Figure 2 As shown in Figure 2, this will result in a bulge in the bottom middle area of the primary ingot after turning. Figure 1 The bulge in the bottom center area of the primary ingot produced by the melting crucible in the turning process is more serious.
[0040] This directly results in a large gap between the head and tail end faces of adjacent primary ingots after splicing the multiple primary ingots after turning. At the same time, due to the limited power of the vacuum plasma welding box, the welds of the multiple primary ingots after welding are very likely to have poor welding, resulting in poor connection strength between the multiple primary ingots, which poses a great hidden danger to the subsequent use of the ingots.
[0041] In addition, if multiple primary ingots are placed in a vacuum consumable arc furnace for welding, compared with using a vacuum plasma welding box to weld single ingots, the assembly efficiency of the vacuum consumable arc furnace is lower, and the cleaning of metal weld nodules and metal splash particles after welding is time-consuming and labor-intensive. When welding multiple ingots, each weld needs to wait for cooling and solidification. These effects will greatly affect the continuous production efficiency of the ingots and increase labor costs.
[0042] The present invention arranges a boss at the middle of the upper end of the crucible bottom pad, so that the center of the bottom of each smelted primary ingot has a groove matching the boss. After turning the two ends of the primary ingot, there will be no bulge in the middle area of the bottom of the primary ingot, which will not lead to an increase in the weld seam and the problem of poor welding. At the same time, the present invention welds the assembled ingots through a vacuum plasma welding box, which can further ensure the elimination of the problem of poor welding and improve production efficiency. The technical solution of the present invention is described in detail below through specific embodiments.
[0043] Example
[0044] refer to Figure 3 A method for eliminating welding defects in a titanium alloy ingot welding box comprises the following steps:
[0045] S1. Place m consumable electrodes in a melting crucible for melting to obtain m primary ingots. In this embodiment, m=5. Figure 1 and Figures 4 to 8 The smelting crucible comprises a cylinder 1 and a cylinder 2, the lower end of the cylinder 1 is sealed and connected to the cylinder 2 through a connecting piece, and a boss 3 is provided at the upper end of the cylinder 2, so that the center of the bottom of each smelted primary ingot has a groove matching the boss 3;
[0046] S2, turning the ingot crown at the top of the first ingot to make it flat, and obtaining 5 top-turned ingots;
[0047] S3. Take out 4 from the 5 top turned ingots, and turn the bottom of each of the taken out top turned ingots to obtain the target turned ingots; the turning thickness during the turning process is less than or equal to the maximum depth of the groove, ensuring that the previous ingot and the next ingot can be connected smoothly during the subsequent splicing process, thereby eliminating the problem of poor welding of the spliced ingots in the welding box.
[0048] S4. References Figures 10 to 11 First, the bottom outer edges and top outer edges of the four target turned ingots are chamfered, and the top outer edge of the remaining top turned ingot is chamfered, and then the four target turned ingots and the remaining top turned ingot are spliced end to end to obtain an assembled ingot; during the splicing process, the bottom of the remaining top turned ingot is a free end of the assembled ingot; before splicing, the target turned ingots and the top turned ingot are chamfered to form a weld at the connection between the previous ingot and the next ingot in the assembled ingot, which can ensure the strength of the subsequent welded ingots. In this embodiment, the size of the chamfer is 20mm×45°.
[0049] S5, placing the assembled ingots horizontally in a vacuum plasma welding box, and performing circumferential welding on the head and tail joints of the assembled ingots by using the vacuum plasma welding box to obtain a welded ingot.
[0050] refer to Figures 4 to 8 In the above embodiments, the depth of the groove is 5 to 20 mm, the groove is truncated cone-shaped and coaxial with the primary ingot, the bottom surface of the groove is flat, the diameter of the groove notch is larger than the diameter of the groove bottom, and the ratio of the diameter of the groove notch to the outer diameter of the primary ingot is 0.15 to 0.75, ensuring that the end face of the subsequent target turning ingot is flat and the previous one can be in smooth contact with the next one.
[0051] In the above embodiment S3, the bottom of the top turning ingot can be turned at a rotation speed of 5 to 20 rpm and a feed rate of 0.2 to 0.5 mm / rev.
[0052] In the above embodiment S5, the welding current of the ring welding is 300 to 550 amperes, and the welding voltage is 45 to 80 volts.
[0053] refer to Fig. 9 In the above embodiments, the bottom surface of the groove may also be a curved surface that is recessed toward the top of the primary ingot.
[0054] In the above embodiment, the cylinder 2 can be obtained by turning, and the specific method is as follows:
[0055] First, obtain the target cylinder, and then turn the edge area of the end of the target cylinder to obtain a barrel 2 with a boss 3, wherein the diameter of the target cylinder can be the diameter of the barrel 2, and the thickness of the target cylinder can be the maximum thickness of the barrel 2. In the process of turning the target cylinder, a chamfer structure can be formed at the upper edge of the boss 3. In this way, the following two effects can be achieved. On the one hand, the strength of the boss 3 can be enhanced to avoid stress concentration on the edge of the boss 3. On the other hand, it is also beneficial to demold the ingot in the melting crucible.
[0056] The cylinder 2 can also be obtained by smelting and casting.
[0057] In the above embodiments, the connecting piece may be a bolt, which can facilitate the maintenance or replacement of parts of the smelting crucible, or may be a connecting piece with other structures.
[0058] The specific embodiments of the present invention enable those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention.
[0059] It should be understood that the present invention is not limited to what has been described above and that various modifications and changes may be made without departing from its scope. The scope of the present invention is limited only by the appended claims.
Claims
1. A method for eliminating welding defects in a titanium alloy ingot welding box, characterized in that: The method comprises the following steps: S1. Place m consumable electrodes in a smelting crucible for smelting to obtain m primary ingots, each of which has a groove at the bottom center; wherein m≥2; S2, turning the ingot crown at the top of the primary ingot to make it smooth, and obtaining m top turned ingots; S3, taking out m-1 top turning ingots from the m top turning ingots, and turning the bottom of each of the taken out top turning ingots to obtain a target turning ingot; S4, assembling the m-1 target turning ingots and the remaining top turning ingot head to tail to obtain an assembled ingot; during the assembly process, the bottom of the remaining top turning ingot is a free end; S5, placing the assembled ingots horizontally in a vacuum plasma welding box, and performing circumferential welding on the head and tail joints of the assembled ingots by using the vacuum plasma welding box to obtain a welded ingot.
2. The method for eliminating welding defects in a titanium alloy ingot welding box according to claim 1, characterized in that: In S4, before assembling, the bottom outer edge and the top outer edge of the target turned ingot are chamfered, and the top outer edge of the remaining top turned ingot is chamfered.
3. The method for eliminating welding defects in a titanium alloy ingot welding box according to claim 1, characterized in that: In S1, the groove is truncated cone-shaped and coaxial with the primary ingot, and the diameter of the groove opening is larger than the diameter of the groove bottom.
4. The method for eliminating welding defects in a titanium alloy ingot welding box according to claim 1, characterized in that: In S1, the depth of the groove is 5 to 20 mm.
5. The method for eliminating welding defects in a titanium alloy ingot welding box according to claim 1, characterized in that: In S3, the turning thickness is less than or equal to the maximum depth of the groove, and the bottom of the top turning ingot is turned at a rotation speed of 5 to 20 rpm and a feed rate of 0.2 to 0.5 mm / rev.
6. The method for eliminating welding defects in a titanium alloy ingot welding box according to claim 1, characterized in that: In S1, the smelting crucible comprises a cylinder (1), the lower end of the cylinder (1) is sealedly connected to a bottom pad (2) via a connecting piece, and the upper end of the bottom pad (2) is provided with a boss (3) matching the groove.
7. The method for eliminating welding defects in a titanium alloy ingot welding box according to claim 2, characterized in that: The dimensions of the chamfers on the target turned ingot and the remaining top turned ingot were 20 mm x 45°.
8. The method for eliminating welding defects in a titanium alloy ingot welding box according to claim 1, characterized in that: In S5, the welding current of the ring welding is 300-550A, and the welding voltage is 45-80V.
9. The method for eliminating welding defects in a titanium alloy ingot welding box according to claim 3, characterized in that: The ratio of the diameter of the groove notch to the outer diameter of the primary ingot is 0.15 to 0.
75.
10. The method for eliminating welding defects in a titanium alloy ingot welding box according to claim 1, characterized in that: The bottom surface of the groove is a plane or a curved surface recessed toward the top of the primary ingot.