Superconducting strip welding tool and welding method

Abstract

The invention belongs to the field of superconducting tapes, and provides a superconducting tape welding tool and a welding method.The tool comprises a first tool piece and a second tool piece, a groove is formed in the surface of the second tool piece, a protruding block matched with the groove is arranged on the first tool piece, and when the first tool piece and the second tool piece are connected, the protruding block is matched with the groove. The protruding blocks and the grooves can clamp two to-be-welded superconducting strips to be welded together in an embedded mode. According to the method, the problems existing in a traditional welding method are solved, the consistency and reliability of connector performance are improved, the service life of superconducting equipment is prolonged, and the method has wide application prospects and important practical value.

Description

Technical Field

[0001] The invention belongs to the field of superconducting tapes, and in particular relates to a superconducting tape welding tool and a welding method. Background Art

[0002] In the complex preparation process of the magnetic field coil, joints are inevitable due to limitations in material length, processing technology, and device design. The existence of joints is an important consideration for the performance and stability of superconducting coils. At present, the commonly used superconducting tape welding method in the industry is to precisely weld the finished tape after packaging by overlapping or bridging. After continuous optimization and improvement of this welding technology, the joint resistance can be controlled below 10 nanoohms (nΩ), which has basically met the needs of commercial applications.

[0003] Nevertheless, this method of welding high-temperature superconducting tapes is not perfect. In actual operation, the welding process is very likely to cause a certain degree of damage to the tape itself and contamination of the tape surface. Although these damages may not have a significant impact on the performance of the coil in the short term, they may gradually become apparent under long-term operation and high-load working conditions, affecting the stability and life of the coil. Summary of the invention

[0004] The purpose of the present invention is to provide a superconducting tape welding tool and a welding method to solve the problem that after two tapes are welded together in the prior art, they cannot be repeatedly disassembled and welded multiple times, and the welding process is very likely to cause a certain degree of damage to the tape itself.

[0005] To achieve the above object, the present invention adopts the following technical solutions: In a first aspect, the present invention provides a superconducting tape welding tool, comprising a first tool piece and a second tool piece, wherein a groove is arranged on the surface of the second tool piece, and a protrusion matching the groove is arranged on the first tool piece, and when the first tool piece and the second tool piece are connected, the protrusion and the groove can be engaged and clamped to hold two superconducting tapes to be welded together.

[0006] Furthermore, the first tooling piece is an upper top plate, the protrusion is arranged on the upper top plate, and the protrusion is a rectangular strip-shaped protrusion; the second tooling piece is a lower bottom plate, the groove is arranged on the lower bottom plate, and the groove is a rectangular strip-shaped groove.

[0007] Furthermore, the width of the rectangular band-shaped groove matches the width of the rectangular band-shaped protrusion, and the height of the rectangular band-shaped protrusion is greater than the depth of the rectangular band-shaped groove.

[0008] Furthermore, the surfaces of the protrusions and the grooves are evenly adhered with Teflon tape or polyimide tape.

[0009] Furthermore, threaded holes are provided on the first tooling piece and the second tooling piece, and the first tooling piece and the second tooling piece are fastened and connected by bolts.

[0010] In a second aspect, the present invention provides a superconducting tape welding system, comprising a superconducting tape welding tool and a heating platform, wherein the superconducting tape welding tool is arranged on the heating platform, the superconducting tape welding tool is used to clamp and fix two superconducting tapes to be welded together, and the heating platform is used to heat to weld and fix the two superconducting tapes to be welded together.

[0011] In a third aspect, the present invention provides a welding method of a superconducting tape welding tool, comprising: Copper strips of equal width are respectively packaged on the surfaces of two superconducting strips; After the copper tape packaging operation is completed, an indium sheet needs to be inserted between the two packaging copper tapes; Place the packaged copper strips and indium sheets in the grooves of the second tooling piece according to a set order, then install the first tooling piece and perform preliminary fixation; Place the entire tooling on a heating table and complete the welding.

[0012] Furthermore, during the heating process of the heating table, the bolts are gradually tightened until a preset maximum torque value is reached; and preliminary fixing is performed by the bolts.

[0013] Furthermore, the copper strip is T2 copper or oxygen-free copper.

[0014] Furthermore, during the process of packaging the copper tape, the copper tape is welded to the surface of the superconducting tape using lead-containing solder.

[0015] Furthermore, the heating table is set to a heating temperature of 120°C-180°C.

[0016] Compared with the prior art, the present invention has the following technical effects: The present invention adopts a special tooling design, including a first tooling piece and a second tooling piece. The second tooling piece is provided with a groove on its surface, and the first tooling piece is provided with a protrusion matching the groove. The interlocking design of the protrusion and the groove provides a stable clamping force, so that the superconducting tape can maintain a fixed position during the welding process, which helps to ensure the quality and consistency of the welded joint and ensures that the two superconducting tapes are firmly compressed. The entire welding process is carried out in a compressed and fixed state, avoiding the problem of damaging the tape itself during the welding process, while also avoiding contamination of the tape surface, enhancing the stability of the coil and extending its service life; the clamping stability also reduces the stress generated by the movement of the tape during the welding process, and reduces the risk of cracks or defects at the joint.

[0017] The height of the rectangular strip-shaped protrusion of the welding tool is greater than the depth of the rectangular strip-shaped groove, which provides sufficient margin space for compacting the superconducting strip to be welded.

[0018] The welding tooling can choose to stick Teflon tape or polyimide tape on the surface of the bump or groove to prevent the superconducting tape from sticking to the tooling.

[0019] The present invention discloses a superconducting tape welding system, wherein the tape welding tool is used to clamp and fix two superconducting tapes to be welded together, and the two superconducting tapes to be welded are welded and fixed together after heating, so as to ensure that the two superconducting tapes are firmly pressed, and the whole welding process is carried out in a pressed and fixed state, so as to avoid the problem of damaging the tape itself during the welding process, and also avoid the contamination of the tape surface, thereby enhancing the stability of the coil and extending the service life; the clamping stability also reduces the stress generated by the movement of the tape during the welding process, and reduces the risk of cracks or defects at the joint.

[0020] The present invention discloses a welding method for a superconducting tape welding tool, which first uses lead-containing solder to encapsulate a layer of copper tape on the surface of the superconducting tape, then inserts a layer of indium sheet between the copper tapes of two superconducting tapes, and welds the two superconducting tapes together under high temperature and external pressure. This method has little effect on the resistance value at the high-temperature superconducting joint. In addition, the indium pressure welding method realizes the repetitive welding and separation operations of the superconducting tape by designing the encapsulated copper tape and the indium sheet. The indium sheet serves as a detachable connecting layer, so that the two tapes can be easily separated and re-welded. This repeatable welding feature is of great advantage for tokamak devices that need to be frequently debugged, repaired or upgraded, and can greatly extend the service life of superconducting equipment.

[0021] Furthermore, the indium pressure welding method achieves stable joint resistance by encapsulating copper tape on the surface of the superconducting tape and padding indium sheets between two copper tapes, utilizing the characteristics of indium's low resistivity, low hardness and low melting point at low temperatures. It is less affected by external factors such as the proficiency of the welders, thus ensuring the consistency and reliability of the joint performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a flow chart of the indium pressure welding method of the present invention.

[0023] Figure 2 It is a three-dimensional diagram of the tooling of the present invention.

[0024] Figure 3 It is a top view of the lower base plate of the present invention.

[0025] Figure 4 It is a front view of the lower base plate of the present invention.

[0026] Figure 5It is a side view of the lower base plate of the present invention.

[0027] Figure 6 For the present invention Figure 5 A partial enlarged view of part A in the middle.

[0028] Figure 7 It is a top view of the upper top plate of the present invention.

[0029] Figure 8 It is a front view of the upper top plate of the present invention.

[0030] Fig. 9 It is a side view of the upper top plate of the present invention.

[0031] Among them: 1. The first tooling part; 2. The second tooling part. DETAILED DESCRIPTION

[0032] The present invention is further described below in conjunction with the accompanying drawings: Example 1, please refer to Figure 2 The present invention provides a superconducting tape welding tool, comprising a first tool piece 1 and a second tool piece 2, wherein a groove is arranged on the surface of the second tool piece 2, and a protrusion matching the groove is arranged on the first tool piece 1. When the first tool piece 1 and the second tool piece 2 are connected, the protrusion and the groove can be engaged and clamped to hold two superconducting tapes to be welded together.

[0033] The welding tool is composed of a first tool part 1 and a second tool part 2. This split design facilitates assembly, disassembly and maintenance of the tool.

[0034] The grooves arranged on the surface of the second tooling piece 2 match the bumps on the first tooling piece 1. This fitting design can ensure that the superconducting tape to be welded is firmly clamped in the tooling, avoiding displacement or deformation of the tape during welding. The fitting design of the bumps and grooves provides a stable clamping force, so that the superconducting tape can maintain a fixed position during welding, which helps to ensure the quality and consistency of the welded joint.

[0035] The clamping stability also reduces stress caused by strip movement during welding, reducing the risk of cracks or defects in the joint.

[0036] A groove is arranged on the surface of the second tooling piece, and a protrusion matching the groove is arranged on the first tooling piece. The cooperation of the groove and the protrusion can clamp the two superconducting tapes to be welded together tightly, ensuring that the two superconducting tapes are firmly pressed. The entire welding process is carried out in a pressed and fixed state, avoiding the problem of damaging the tape itself during the welding process, and also avoiding contamination of the tape surface, thereby enhancing the stability of the coil and extending its service life.

[0037] The tooling design can adapt to superconducting tapes of different widths and thicknesses by simply adjusting the size of the bumps and grooves. This adaptability enables the tooling to be used for welding multiple types of superconducting tapes, improving its versatility and flexibility.

[0038] The split design of the tooling also makes it easy to replace or adjust the tooling parts according to actual needs to meet the requirements of different welding tasks.

[0039] The interlocking design of the protrusion and the groove makes the assembly and disassembly process of the tooling simple and quick, reducing the labor intensity and time cost of the operators.

[0040] The structure of the tooling is clear and straightforward, and operators can easily understand and master its use, which improves the efficiency and accuracy of welding work.

[0041] The stable clamping force and adaptable design together ensure the position accuracy and stability of the superconducting tape during the welding process, which is a prerequisite for obtaining high-quality welded joints.

[0042] By using this tool for welding, the influence of human factors on the quality of the joint can be reduced, and the reliability and consistency of the welded joint can be improved.

[0043] In summary, the superconducting tape welding tool provides reliable tools and support for the welding of superconducting tapes through reasonable structural design, stable clamping force, adaptability and flexibility, ease of operation, and welding quality assurance. The design of this tool not only improves the efficiency and accuracy of welding work, but also ensures the quality and consistency of the welded joints, which is of great significance to the application and development of superconducting technology.

[0044] Working principle: Split design: The tooling adopts a split design, which is easy to assemble, disassemble and maintain.

[0045] Chimeric clamping: The groove of the second tooling piece matches the protrusion of the first tooling piece. The chimeric design ensures that the superconducting tape is firmly clamped in the tooling to avoid displacement or deformation of the tape during welding.

[0046] Stable clamping force: The interlocking design of the bumps and grooves provides a stable clamping force, keeping the superconducting tape in a fixed position during the welding process, helping to ensure the quality and consistency of the welded joint.

[0047] Adaptability and flexibility: The tooling design can adapt to superconducting tapes of different widths and thicknesses by simply adjusting the size of the bumps and grooves. This adaptability improves the versatility and flexibility of the tooling.

[0048] Embodiment 2, the present invention provides a superconducting tape welding tool, specifically comprising: two major components, upper and lower. The lower base plate is the basic support part of the entire tool, and a groove with a width of 12 mm and a depth of 1 mm is designed in the center, which is intended to firmly accommodate and fix two superconducting tapes containing copper packaging tapes and indium sheets for welding. The design of the groove ensures that the superconducting tape and the indium sheet can maintain the correct position during the welding process to avoid displacement or deformation.

[0049] The upper top plate is a key component that matches the lower bottom plate. The center of the upper top plate is equipped with a bump that is the same width as the bottom plate groove, that is, 12 mm and 1.5 mm high. This bump matches the groove of the lower bottom plate in size and shape. When the two are combined, they can tightly clamp the superconducting tape and indium sheet to ensure that they maintain stable contact and correct position during the welding process. In order to further enhance the stability of the clamping, the tooling is also fastened by external bolts so that the upper and lower components can be tightly connected together to form a whole. At the same time, the overall heating method is also adopted to ensure that the superconducting tape and indium sheet can be evenly heated during the welding process, so as to achieve the best welding effect.

[0050] In actual operation, in order to prevent the superconducting tape from sticking to the tooling, which affects the welding quality and the reuse of the tooling, a layer of Teflon tape or polyimide tape can be pasted on the surface of the bumps of the upper plate or (and) the grooves of the lower plate. These tapes have good high temperature resistance and anti-adhesion properties, which can effectively prevent the superconducting tape from sticking to the tooling and protect the surface of the tooling and superconducting tape from damage.

[0051] Working principle: Stable clamping: The grooves of the lower base plate and the protrusions of the upper top plate fit tightly and are fastened by external bolts to form a whole, ensuring that the superconducting tape and indium sheet maintain stable contact and correct position during the welding process.

[0052] Overall heating: The overall heating method is adopted to ensure that the superconducting tape and indium sheet are heated evenly to achieve the best welding effect.

[0053] Anti-adhesion measures: Teflon tape or polyimide tape is pasted on the surface of the protrusions of the upper top plate or (and) the grooves of the lower bottom plate to prevent the superconducting tape from adhering to the tooling and protect the surface of the tooling and the superconducting tape from damage.

[0054] Embodiment 3, the present invention provides a welding method of a superconducting tape welding tool, comprising: Copper strips of equal width are respectively packaged on the surfaces of two superconducting strips; After the copper tape packaging operation is completed, an indium sheet needs to be inserted between the two packaging copper tapes; Place the packaged copper strips and indium sheets in the grooves of the second fixture in a set order, then install the first fixture and use bolts to preliminarily fix them; Place the entire tooling on the heating table. During the heating process, gradually tighten the bolts until the preset maximum torque value is reached to complete the welding. The heating table heating setting temperature is 120℃-180℃, preferably 160℃.

[0055] When the two strips are welded together, they form an inseparable whole. This means that once the welding is completed, the strips cannot be disassembled and welded repeatedly. This feature limits the flexibility and maintainability of the coil to a certain extent. The inability to weld and separate repeatedly is undoubtedly a considerable challenge for the Tokamak device that needs to be frequently debugged, repaired or upgraded.

[0056] First, a layer of copper tape is encapsulated on the surface of the superconducting tape using lead-containing solder, and then a layer of indium sheet is placed between the copper tapes of the two superconducting tapes. Under high temperature and external pressure, the two superconducting tapes are welded together. This method has little effect on the resistance value at the high-temperature superconducting joint. In addition, the indium pressure welding method realizes the repetitive welding and separation operations of the superconducting tape by designing the encapsulated copper tape and indium sheet. The indium sheet serves as a detachable connecting layer, allowing the two tapes to be easily separated and re-welded. This repeatable welding feature is of great advantage for tokamak devices that require frequent debugging, maintenance or upgrades, and can greatly extend the service life of superconducting equipment.

[0057] Furthermore, the indium pressure welding method achieves stable joint resistance by encapsulating copper tape on the surface of the superconducting tape and padding indium sheets between two copper tapes, utilizing the characteristics of indium's low resistivity, low hardness and low melting point at low temperatures. It is less affected by external factors such as the proficiency of the welders, thus ensuring the consistency and reliability of the joint performance.

[0058] The entire welding process is simple and convenient to operate. You only need to place the superconducting tape, copper tape and indium sheet in the tooling according to the established packaging order, and then heat and apply external pressure to complete the welding.

[0059] The indium pressure welding method selects T2 copper or oxygen-free copper as the material for the packaging copper tape, which has a low resistivity at liquid nitrogen temperature, and minimizes their impact on the joint resistance value by precisely controlling the thickness of the solder layer and the indium sheet.

[0060] The indium pressure welding method has a wide range of application prospects, especially for the preparation of detachable TF superconducting coils. This method not only ensures the detachability of the coil at any time, facilitating replacement and maintenance, but also improves the flexibility and maintainability of superconducting equipment. Compared with traditional welding methods, the indium pressure welding method has significant advantages in joint resistance stability, strip protection, repeatable welding, ease of operation and application prospects.

[0061] In summary, as an innovative high-temperature superconducting tape welding technology, indium pressure welding not only solves the problems existing in traditional welding methods, but also improves the consistency and reliability of joint performance, extends the service life of superconducting equipment, and has broad application prospects and important practical value.

[0062] Working principle: Copper tape packaging: The surface of the superconducting tape is packaged with copper tape to provide additional support and protection.

[0063] Indium sheet insertion: The indium sheet acts as a welding medium to ensure that the two superconducting tapes are welded together under high temperature and external pressure.

[0064] Tool clamping and heating: The tool clamps the superconducting tape and indium sheet through the interlocking design of bumps and grooves. The bolts are gradually tightened during the heating process to ensure the tightness and stability of the welded joint.

[0065] Embodiment 4, the present invention provides a welding method of a superconducting tape welding tool, specifically comprising: Figures 3 to 6 The structure of the bottom plate and the packaging sequence are shown in detail. The width of the superconducting tape is set to 12 mm, and the connection between it and the packaging copper is soldered with lead-containing solder, and the thickness of the solder layer is precisely controlled to 0.01 mm. This design aims to minimize the impact of the solder layer on the resistance value of the indium crimping joint. The thickness of the packaging copper is 0.1 mm, and the material used is T2 copper. After searching the data, the resistivity of T2 copper at liquid nitrogen temperature is about 2.4*10 -9 Ω·m, according to the material volume resistance calculation formula: R=ρL / S (where R represents resistance, ρ represents resistivity, L represents the length of the material, and S represents the cross-sectional area of ​​the material), it can be calculated that the volume resistance of the packaged copper is about 10-18Ω. Between the two packaged coppers, an indium sheet with a thickness of 0.1 mm and the same width as the superconducting tape (i.e. 12 mm) was selected. After heating and applying external pressure, the thickness of the indium sheet will be reduced to less than 0.08 mm. At this point, using the material volume resistance calculation formula again for estimation, we can deduce that the volume resistance of the indium sheet between the packaged coppers is also about 10 -18 Ω, which is basically the same as the bulk resistance of T2 copper.

[0066] Figures 7 to 9It is a three-dimensional diagram of the upper plate structure of the welding tooling, which is mainly used to cooperate with the lower base plate to press the superconducting tape and indium sheet. The material of the upper plate and the lower base plate can be a metal block with good thermal conductivity, such as copper, anodized aluminum, etc.

[0067] After assembling all parts and heating and tightening the bolts, the superconducting tape indium press detachable joint was prepared, and then the resistance test was carried out using the four-lead method in a liquid nitrogen environment. The test results showed that the resistance value of the indium press detachable joint was 3.66nΩ, which was almost negligible compared with the resistance value of the conventional welding joint without the addition of encapsulated copper and indium sheet, which was 3.39nΩ. This is enough to show that the indium press welding technology has little effect on the resistance of the superconducting tape joint, and can completely replace the traditional direct lap welding method.

[0068] In the indium pressure welding test, we also tested the critical current of the strip. The critical current of the strip after welding was 443A. After the test, the two superconducting strips were separated at the welding point, and the critical current of the two superconducting strips after separation was tested. The test results showed that the critical currents of the two superconducting strips were 434A and 445A respectively, indicating that the indium pressure welding method has almost no damage to the disassembled superconducting strips.

[0069] The indium sheet between the two packaging tapes can ensure that the two superconducting tapes can be repeatedly disassembled and indium pressed and welded, and the packaging copper can ensure that the superconducting tape is not damaged during multiple disassembly and indium pressing. The indium pressing method for welding superconducting tape joints has a wide range of application prospects and can be used for the preparation of detachable TF superconducting coils, which can ensure that the coils can be disassembled at any time, convenient for replacement and maintenance, and can greatly extend the service life of superconducting equipment.

[0070] Working principle and effect verification: Minimize resistance effects: By precisely controlling the thickness of the solder layer and the indium sheet, their effects on the resistance value of the indium crimp joint are minimized.

[0071] Resistance test: The resistance test was performed using the four-lead method in a liquid nitrogen environment. The results showed that the resistance value at the indium pressed detachable joint was almost negligible compared to the resistance value of the conventional soldered joint without the addition of encapsulated copper and indium sheets.

[0072] Critical current detection: The critical current of the strip after welding is 443A, and the critical currents of the two superconducting strips after splitting are 434A and 445A respectively, indicating that the indium pressure welding method has almost no damage to the disassembled superconducting strips.

[0073] Repeatable disassembly and welding: The design of indium sheet and packaging copper ensures that the superconducting tape can be repeatedly disassembled and indium pressed and welded, which extends the service life of superconducting equipment and has broad application prospects.

[0074] In summary, the superconducting tape welding tool and the welding method of the present invention provide reliable tools and support for the welding of superconducting tapes through reasonable structural design, stable clamping force, adaptability and flexibility, ease of operation, and welding quality assurance. The design of this tool and method not only improves the efficiency and accuracy of welding work, but also ensures the quality and consistency of welded joints, which is of great significance to the application and development of superconducting technology.

[0075] Embodiment 5, the present invention provides a superconducting tape welding system, comprising the above-mentioned superconducting tape welding tool and a heating platform, wherein the superconducting tape welding tool is arranged on the heating platform.

[0076] Place the entire tooling on the heating table. During the heating process, gradually tighten the bolts until the preset maximum torque value is reached to complete the welding.

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A superconducting tape welding tool, characterized in that: The invention comprises a first tooling piece (1) and a second tooling piece (2), wherein a groove is arranged on the surface of the second tooling piece (2), and a convex block matching the groove is arranged on the first tooling piece (1), and when the first tooling piece (1) and the second tooling piece (2) are connected, the convex block and the groove can be engaged to clamp two superconducting tapes to be welded together.

2. A superconducting tape welding tool according to claim 1, characterized in that: The first tooling piece (1) is an upper top plate, the convex block is arranged on the upper top plate, and the convex block is a rectangular strip-shaped convex block; the second tooling piece (2) is a lower bottom plate, the groove is arranged on the lower bottom plate, and the groove is a rectangular strip-shaped groove.

3. A superconducting tape welding tool according to claim 2, characterized in that: The width of the rectangular band-shaped groove matches the width of the rectangular band-shaped protrusion, and the height of the rectangular band-shaped protrusion is greater than the depth of the rectangular band-shaped groove.

4. A superconducting tape welding tool according to claim 1, characterized in that: The surfaces of the protrusions and the grooves are evenly adhered with Teflon tape or polyimide tape.

5. A superconducting tape welding tool according to claim 1, characterized in that: The first tooling piece (1) and the second tooling piece (2) are both provided with threaded holes, and the first tooling piece (1) and the second tooling piece (2) are fastened and connected by bolts.

6. A superconducting tape welding system, characterized in that: It comprises a superconducting tape welding tool and a heating platform as described in any one of claims 1 to 5, wherein the superconducting tape welding tool is arranged on the heating platform, the superconducting tape welding tool is used to clamp and fix two superconducting tapes to be welded together, and the heating platform is used to heat to weld and fix the two superconducting tapes to be welded together.

7. A welding method for a superconducting tape welding tool according to any one of claims 1 to 5, or a superconducting tape welding system according to claim 6, characterized in that: include: Copper strips of equal width are respectively packaged on the surfaces of two superconducting strips to be welded; After the copper tape packaging operation is completed, an indium sheet needs to be inserted between the two copper tapes; Place the packaged copper strips and indium sheets in the grooves of the second tooling piece according to a set order, then install the first tooling piece and perform preliminary fixation; Place the entire tooling on a heating table and complete the welding.

8. A welding method for a superconducting tape welding tool according to claim 7, characterized in that: During the heating process of the heating table, gradually tighten the bolts until the preset maximum torque value is reached; preliminary fixing is performed by the bolts.

9. The welding method of a superconducting tape welding tool according to claim 7, characterized in that: The copper strip is T2 copper or oxygen-free copper.

10. The welding method of a superconducting tape welding tool according to claim 7, characterized in that: During the copper tape packaging process, lead-containing solder is used to solder the copper tape to the surface of the superconducting tape.

11. A welding method for a superconducting tape welding tool according to claim 7, characterized in that: The heating table heating setting temperature is 120℃-180℃.

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