Apparatus for processing the outer conductor of a corrugated outer conductor radio frequency coaxial feedline

Abstract

The application relates to the technical field of communication cables, in particular to a processing device for an outer conductor of a corrugated outer conductor radio frequency coaxial feeder. The corrugated outer conductor radio frequency coaxial feeder comprises, from inside to outside, an inner conductor, an insulating layer, an outer conductor and a sheath layer in sequence, the outer conductor is a strip-shaped metal enclosed in a ring shape, the two side edges of the strip-shaped metal are arranged in opposite directions by being bent, the outer conductor is made in a hanging and overlapping mode by the two side edges of the strip-shaped metal and is coaxially arranged outside the insulating layer, an adhesive is arranged at the overlapping position of the outer conductor, and the outer side wall of the outer conductor is corrugated. The outer conductor processing device comprises an operation platform and, arranged along the length direction of the operation platform in sequence, a cleaning assembly, a bending piece, a coating adhesive assembly, a forming assembly and a blow-drying assembly. The radio frequency coaxial feeder provided by the application has the effects of simple processing technology, low production cost, stable structure of the produced radio frequency coaxial feeder and excellent product performance.

Description

Technical Field

[0001] This invention relates to the field of communication cable technology, and more particularly to a processing apparatus for the outer conductor in a corrugated outer conductor radio frequency coaxial feeder. Background Technology

[0002] With the continuous improvement of manufacturing technology for radio frequency coaxial feeders used in mobile communication access systems, many new processes have emerged in the manufacturing of the outer conductor of radio frequency coaxial feeders. These processes are used to improve the existing product structure of radio frequency coaxial feeders, increase production efficiency, and reduce production costs.

[0003] The outer conductor is generally formed by wrapping together strips of metal. To improve the bending performance of the outer conductor, the surface of the outer conductor needs to be corrugated. Therefore, the overlapping joints of the strip metal need to be stably connected. The existing manufacturing process for corrugated outer conductor RF coaxial feeders is argon arc welding corrugation process. Specifically, the edges of the copper strip (or aluminum strip) are first cut off. Then, under the protection of inert gas argon, a tungsten electrode is used to melt the joint of the cut copper strip (or aluminum strip) after wrapping with high frequency and high current, welding it into a tubular shape. This achieves the outer conductor copper strip (or aluminum strip) tightly covering the outside of the feeder insulation layer. Finally, a corrugation machine forms a ring or spiral appearance on the outer conductor.

[0004] While existing argon arc welding (argon arc welding) processes offer high welding efficiency, the large heat-affected zone creates a risk of burning the inner insulation layer (primarily polyethylene). Localized annealing can cause stress damage to the outer conductor, leading to surface cracks, pinholes, and other incomplete welds, impacting the feeder's electrical performance. Furthermore, when using low-cost, relatively reactive aluminum strips as the outer conductor, the welding process requires the use of scarce helium for protection, resulting in inconsistent weld quality. Additionally, argon arc welding is susceptible to factors such as unstable welding current, impure shielding gas, and improper production speed, leading to incomplete welds, burn-through, cable breaks, and reduced product yield and production efficiency. Moreover, argon arc welding generates high current density, producing 5-30 times more ultraviolet radiation and 1-1.5 times more infrared radiation than conventional shielded metal arc welding (SMAW), along with higher ozone levels. Overall, the process is energy-intensive and poses significant health risks to operators.

[0005] Therefore, it is necessary to provide a radio frequency coaxial feeder outer conductor manufacturing and processing device that can effectively solve the above problems and the corresponding radio frequency coaxial feeder structure. Summary of the Invention

[0006] The technical problem to be solved by this invention is that the existing argon arc welding method used for corrugated outer conductor radio frequency coaxial feed lines is costly and has poor welding quality.

[0007] Therefore, the present invention provides a processing apparatus for the outer conductor in a wrinkled outer conductor radio frequency coaxial feeder, which has the advantages of simple process, low production cost, stable structure of the produced radio frequency coaxial feeder and excellent product performance.

[0008] The technical solution adopted by this invention to solve its technical problem is: A corrugated outer conductor radio frequency coaxial feeder, comprising, Inner conductor, An insulating layer, which is coaxially disposed on the outside of the inner conductor; The outer conductor is a strip of metal that is enclosed in a ring shape. The two sides of the strip of metal are bent in opposite directions. The outer conductor is made by hooking and overlapping the two sides of the strip of metal and is coaxially installed outside the insulation layer. An adhesive is provided at the overlap of the outer conductor. A pleated structure is provided on the outer wall of the outer conductor to improve the flexibility of the outer conductor. A sheath layer, which is coaxially disposed on the outside of the outer conductor.

[0009] By adopting the above technical solution, the outer conductor is made by overlapping the two sides of a strip of metal with hooks, and the overlap is glued together with adhesive. This facilitates the fabrication of the outer conductor. Compared with the existing argon arc welding method, this hook-and-loop overlapping and gluing method does not require prior training for operators, has a simple process, lower processing costs, fewer factors affecting the quality of the finished product during processing, and results in higher processing quality and a higher yield. This invention uses mechanical hook-and-loop overlapping and gluing assistance, therefore the structure at the joint of the strip of metal is stable and can withstand the corrugation operation on the surface of the outer conductor.

[0010] Furthermore, the adhesive is resistant to high temperatures, and its ambient temperature resistance is -30 ℃ to 150 ℃.

[0011] An apparatus for processing the outer conductor in a wrinkled outer conductor radio frequency coaxial feeder, comprising, Operating platform, and A cleaning assembly for cleaning the edges of a strip of metal used to make an outer conductor; A bending element for bending the sides of a strip of metal used to make an outer conductor; A coating adhesive assembly is used to apply adhesive to the side edges of a strip of metal used to make an outer conductor. A molding assembly for curling strip metal to glue its adhesive-coated edges together to form an outer conductor; A drying assembly for promoting the drying of adhesive on the edge of a strip of metal; The cleaning component, bending component, coating and bonding component, molding component, and drying component are arranged sequentially along the length of the operating platform, and the end of the operating platform closest to the cleaning component is the feeding end.

[0012] Furthermore, the cleaning assembly includes two mounting plates and cleaning pads mounted on the mounting plates. The two mounting plates are arranged parallel to each other. The mounting plates are set on the operating platform by an adjusting member, which is used to adjust the spacing between the mounting plates and the height of the mounting plates in the vertical direction. When the strip metal passes between the two cleaning pads, the cleaning pads abut against the opposite edges of the strip metal.

[0013] Furthermore, the cleaning assembly also includes an air gun, which is mounted on the operating platform and has its nozzle facing the edge of the strip metal.

[0014] Furthermore, the width of the folding plate is wider at one end near the feeding end than at the other end, and the side edges of the folding plate are bent toward the two side walls of the folding plate respectively. Along the wider end of the folding plate toward the other end, the side edges of the folding plate bend closer to the side wall of the folding plate.

[0015] Furthermore, the folded edge plate is set on the operating table via an adjusting component.

[0016] Furthermore, two coating and bonding components are provided, symmetrically arranged. Each coating and bonding component includes a glue container, a guide tube, and a brush. The glue container has an opening with a sealing cap at the top, and its bottom is connected to the guide tube. The end of the guide tube away from the glue container is connected to the brush. The brush is used to abut against the edge of the strip metal. The two glue containers each contain two components of the adhesive, and the two components of the adhesive have adhesive properties after being mixed.

[0017] Furthermore, the forming component includes a forming cylinder and a guide strip. The forming cylinder is flared and its axial direction is along the length of the operating platform. The larger end of the forming cylinder faces the feeding end. The inner diameter of the larger end of the forming cylinder is larger than the width of the strip metal. The inner diameter of the smaller end of the forming cylinder is adapted to the outer diameter of the outer conductor. The guide strip is disposed on the inner wall of the forming cylinder. The guide strip is wedge-shaped and its length is along the axial direction of the forming cylinder. The end of the guide strip near the feeding end is inclined away from the axial direction of the forming cylinder.

[0018] Furthermore, the inner diameter of the smaller end of the forming cylinder port is the sum of the outer diameter of the insulating layer and five times the thickness of the strip metal.

[0019] The beneficial effects of this invention are that the use of mechanical hook-and-loop splicing and adhesive bonding to process the outer conductor of the RF coaxial feeder is more cost-effective, simpler to process, and provides better connection stability compared to argon arc welding. The design of the outer conductor processing device is based on the outer conductor structure of this invention and is tailored to the specific implementation steps in the production process. Attached Figure Description

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0021] Figure 1 This is a schematic diagram of the structure of the novel wrinkled outer conductor radio frequency coaxial feeder in this invention.

[0022] Figure 2 This is a schematic cross-sectional view of the novel wrinkled outer conductor radio frequency coaxial feeder of this invention.

[0023] Figure 3 This is a schematic diagram of the overlapping structure of the outer conductor in this invention.

[0024] Figure 4 This is a schematic diagram of the processing device in this invention.

[0025] Figure 5 This is a schematic diagram of the cleaning component in this invention.

[0026] Figure 6 This is a schematic diagram of the folded edge component in this invention.

[0027] Figure 7 This is a schematic diagram of the coated adhesive component in this invention.

[0028] Figure 8 This is a schematic diagram of the molding component in this invention.

[0029] Figure 9 This is a structural schematic diagram showing the positional relationship between the forming cylinder and the guide strip in this invention.

[0030] Figure 10 This is a schematic diagram of the drying component in this invention.

[0031] In the diagram: 1. Inner conductor; 2. Insulation layer; 3. Outer conductor; 4. Sheath layer; 5. Processing device; 50. Cleaning assembly; 500. Mounting plate; 501. Cleaning pad; 502. Air gun; 51. Bending component; 52. Coating and bonding assembly; 520. Glue bottle; 521. Guide tube; 522. Brush; 53. Forming assembly; 530. Forming cylinder; 531. Guide strip; 54. Drying assembly; 540. Drying cylinder; 541. Hot air blower; 55. Operating platform; 6. Adjusting component; 7. Wire core pay-off frame; 71. Wire core; 8. Copper strip pay-off frame; 81. Copper strip; 9. Corrugating device. Detailed Implementation

[0032] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0033] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the components or elements referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention. Furthermore, features defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0034] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0035] Reference Figure 1 and Figure 2 A corrugated outer conductor radio frequency coaxial feeder includes, from the inside out, an inner conductor 1, an insulating layer 2, an outer conductor 3, and a sheath layer 4, which are arranged coaxially.

[0036] Reference Figure 3The outer conductor 3 is a ring-shaped strip of metal, which can be a copper strip 81 or an aluminum strip. In this embodiment, the strip is a copper strip 81 with a thickness of 0.12–0.23 mm. The two sides of the copper strip 81 are bent in opposite directions and coaxially mounted outside the insulation layer 2 by hook-and-loop connection. An adhesive is provided at the overlap between the outer conductor 3 and the insulation layer 2. The adhesive is heat-resistant and has an ambient temperature resistance of -30 ℃ to 150 ℃. The adhesive includes two components, A and B, which, when mixed, form a sticky adhesive. The outer wall of the outer conductor 3 has a pleated structure to improve its flexibility. Specifically, this pleated structure can be multiple parallel and equidistant annular grooves on the outer wall of the outer conductor 3, or threaded grooves on the outer wall of the outer conductor 3, resulting in a regular pleated structure on the radial cross-section of the outer conductor 3.

[0037] Reference Figure 4 An external conductor processing apparatus 5 includes an operating platform 55 and a cleaning component 50, a bending component 51, a coating and bonding component 52, a forming component 53, and a drying component 54 arranged sequentially along the length of the operating platform 55.

[0038] Reference Figure 4 The copper strip pay-off frame 8 is wound with copper strip 81 for making the outer conductor 3, and the wire core pay-off frame 7 is wound with wire core 71 formed by the inner conductor 1 and the insulation layer 2. The existing wire core pay-off frame 7 and copper strip pay-off frame 8 are set at the same end of the operating platform 55, and the existing corrugating device 9 is set at the other end of the operating platform 55. The cleaning component 50 is set close to the wire core pay-off frame 7 and copper strip pay-off frame 8, with the end where the wire core pay-off frame 7 and copper strip pay-off frame 8 are located as the feeding end of the operating platform 55; the corrugating device 9 is the existing corrugating equipment for the outer conductor 3. During production, it is necessary to ensure that the rotation direction of the corrugating head is consistent with the hook-overlap direction of the metal outer conductor 3, so as to further press the strip metal at the hook-overlap firmly.

[0039] Reference Figure 5 The cleaning assembly 50 includes two mounting plates 500 and a cleaning pad 501 and an air gun 502 mounted on the mounting plates 500. The two mounting plates 500 are arranged parallel to each other. In this embodiment, the two mounting plates 500 are arranged vertically and are mounted on the operating platform 55. The mounting plates 500 are made of nylon. The cleaning pad 501 is detachably mounted on the mounting plate 500 and is a dust-removing soft pad. When the copper strip 81 passes between the two cleaning pads 501, the edges of the cleaning pads 501 abut against the opposite edges of the copper strip 81. The air gun 502 is mounted on the operating platform 55, and the nozzle of the air gun 502 is directed towards the copper strip 81.

[0040] Reference Figure 6The bending part 51 is set as a folding plate. The width of the folding plate is wider at one end near the feeding end than at the other end. The width of the wider end of the folding plate is adapted to the width of the copper strip 81. The side edges of the folding plate are bent towards the two side walls of the folding plate respectively. The width of the bent part is 2-3mm. Along the direction from the wider end of the folding plate towards the other end, the bent part on the folding plate is bent closer to the side wall of the folding plate.

[0041] Reference Figure 7 There are two adhesive coating components 52, which are arranged symmetrically. Each adhesive coating component 52 includes an adhesive container 520, a guide tube 521, and a brush 522. The adhesive container 520 has an opening with a sealing cap at the top, and its bottom is connected to the guide tube 521. The end of the guide tube 521 away from the adhesive container 520 is connected to the brush 522. The brush 522 is used to abut against the edge of the strip metal. The two adhesive containers 520 contain two components of adhesive, A and B, respectively.

[0042] Reference Figure 8 and Figure 9 The forming component 53 includes a forming cylinder 530 and a guide bar 531. The forming cylinder 530 is flared and has a length of 40 cm to 50 cm. Its axial direction is set along the length of the operating platform 55. The larger end of the forming cylinder 530 faces the feeding end. The inner diameter of the larger end of the forming cylinder 530 is larger than the width of the strip metal. The inner diameter of the smaller end of the forming cylinder 530 is adapted to the outer diameter of the outer conductor 3. The guide bar 531 is set on the top surface of the inner sidewall of the forming cylinder 530. The guide bar 531 is wedge-shaped and its length is set along the axial direction of the forming cylinder 530. The end near the feeding end is inclined away from the axial direction of the forming cylinder 530. The guide bar 531 has a length of 15 cm to 20 cm and a width of 1 / 5 of the width of the strip metal.

[0043] Reference Figure 10 The drying device includes a drying cylinder 540 and a hot air blower 541. The drying cylinder 540 is a cylindrical metal tube with a length of 20cm to 30cm and an outer diameter of 1.5 to 2 times that of the insulation layer 2. The metal tube is fixed on the operating platform 55. A mounting hole is opened at the top center of the drying cylinder 540, and the hot air blower 541 is connected to the mounting hole on the drying cylinder 540. The air outlet of the hot air blower 541 is set towards the inside of the drying cylinder 540 through the mounting hole.

[0044] Adjusting components 6 are connected between the mounting plate 500, the folding plate, the glue container 520, the drying cylinder 540, and the operating platform 55. The adjusting components 6 are used to adjust the distance between the mounting plate 500, the folding plate, the glue container 520, the drying cylinder 540, and the operating platform 55. In this embodiment, the adjusting component 6 is a cylinder. The adjusting component 6 can adjust the spacing between the mounting plates 500 and the vertical height of the mounting plate 500, the folding plate, the glue container 520, and the drying cylinder 540, so that the copper strip 81 and the insulating layer 2 can pass horizontally through the cleaning component 50, the bending component 51, the coating and bonding component 52, the forming component 53, the drying component 54, and the embossing device 9.

[0045] The implementation principle of this embodiment is as follows: pull out one end of the copper strip 81 on the copper strip pay-off frame 8. The plane on which the copper strip 81 is located is a vertical plane. Let it pass through the cleaning component 50, bending component 51, coating and bonding component 52, forming component 53, drying component 54, and corrugating device 9 in sequence. Pull out one end of the wire core 71 on the wire core pay-off frame 7. The plane on which the insulation layer 2 is located is a vertical plane. Let it pass through the forming component 53, drying component 54, and corrugating device 9 in sequence.

[0046] The copper strip 81 passes through the cleaning assembly 50 and passes between the two mounting plates 500. The edge of the copper strip 81 is opposite to the cleaning pad 501. When the copper strip 81 passes through the cleaning assembly 50, the cleaning pad 501 wipes the edge of the copper strip 81 to clean it.

[0047] After the cleaning component 50 moves from the wider end of the folding plate to the narrower end of the folding plate, the two sides of the copper strip 81 bend towards the center of the folding plate under the pressure of the bent part on the folding plate, thereby realizing the bending of the two sides of the copper strip 81 towards the two sides of the copper strip 81.

[0048] After the copper strip 81 is bent, it passes through the adhesive coating assembly 52. ​​The substance in the adhesive bottle 520 flows through the guide tube 521 to the brush 522. The brush 522 applies components A and B of the adhesive to the bent parts on both sides of the copper strip 81.

[0049] After being coated with adhesive, the copper strip 81 and the insulating layer 2 enter the forming cylinder 530 together. Along the direction of the guide bar 531, the copper strip 81 is inclined downward away from the bent edge set on the bottom surface, and hooks together with the bent edge on the other side of the copper strip 81. The A and B components on the bent edge of the copper strip 81 come into contact and mix, and glue the two sides of the copper strip 81 together. After being glued together, the copper strip 81 is curled into a cylindrical shape to form the outer conductor 3 wrapped around the wire core 71.

[0050] Finally, the outer conductor 3 is wrapped around the insulation layer 2 and then blown into the drying cylinder 540 by the drying assembly 54, the texturing device 9, and the hot air blower 541 to dry the glued joint of the outer conductor 3. The temperature of the hot air blower needs to be adjusted according to the production speed. The texturing device 9 rolls patterns on the outer wall of the outer conductor 3 to press the copper strip 81 at the hook overlap firmly.

[0051] In summary, the method of mechanical hook-and-loop splicing and adhesive bonding for processing the outer conductor 3 of the RF coaxial feeder is more cost-effective, simpler, and provides better connection stability compared to argon arc welding. The design of the outer conductor 3 processing device is based on the structure of the outer conductor 3 of this invention and is determined according to the specific implementation steps in the production process.

[0052] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined by the scope of the claims.

Claims

1. An apparatus for processing the outer conductor of an outer conductor corrugated radio frequency coaxial feedline, characterized by, The wrinkled outer conductor RF coaxial feed line includes: Inner conductor (1), and An insulating layer (2) is coaxially disposed on the outside of the inner conductor (1); The outer conductor (3) is a strip of metal that is enclosed in a ring shape. The two sides of the strip of metal are bent in opposite directions. The outer conductor (3) is made by hooking and overlapping the two sides of the strip of metal and is coaxially disposed outside the insulation layer (2). The overlap of the outer conductor (3) is provided with adhesive. The outer side wall of the outer conductor (3) is provided with a pleated structure to improve the flexibility of the outer conductor. Sheath layer (4), which is coaxially disposed on the outside of the outer conductor (3); The processing apparatus for the outer conductor (3) includes: Operating platform (55), and A cleaning component (50) is used to clean the edges of the strip metal used to make the outer conductor (3); A bending element (51) is used to bend the side of a strip of metal used to make an outer conductor (3); A coating adhesive assembly (52) is used to apply adhesive to the side edges of a strip of metal used to make an outer conductor (3); A molding component (53) is used to roll up a strip of metal to glue the edges of its adhesive coating together to form an outer conductor (3); Drying assembly (54) for promoting the drying of the adhesive on the edge of the strip metal; The cleaning component (50), bending component (51), coating and bonding component (52), forming component (53), and drying component (54) are arranged sequentially along the length of the operating platform (55), and the end of the operating platform (55) closest to the cleaning component (50) is the feeding end.

2. The apparatus of claim 1, wherein, The cleaning assembly (50) includes two mounting plates (500) and cleaning pads (501) mounted on the mounting plates (500). The two mounting plates (500) are arranged parallel to each other. The mounting plates (500) are set on the operating platform (55) by means of an adjusting member (6). The adjusting member (6) is used to adjust the spacing between the mounting plates (500) and the height of the mounting plates (500) in the vertical direction. When the strip metal passes between the two cleaning pads (501), the cleaning pads (501) abut against the opposite edges of the strip metal.

3. The apparatus of claim 1, wherein, The cleaning assembly (50) also includes an air gun (502) which is mounted on the operating platform (55) and has its nozzle facing the edge of the strip metal.

4. The apparatus of claim 1, wherein, The bending member (51) is configured as a folding plate. The width of the folding plate is wider at one end near the feeding end than at the other end. The side edges of the folding plate are bent toward the two side walls of the folding plate respectively. The side edges of the folding plate are bent closer to the side wall of the folding plate along the wider end toward the other end.

5. The apparatus for processing the outer conductor in a wrinkled outer conductor radio frequency coaxial feeder according to claim 4, characterized in that, The folded edge plate is set on the operating table via an adjusting component (6).

6. The apparatus for processing the outer conductor in a wrinkled outer conductor radio frequency coaxial feeder according to claim 1, characterized in that, Two coating and bonding components (52) are provided and are arranged symmetrically. Each coating and bonding component (52) includes a glue container (520), a guide tube (521), and a brush (522). The glue container (520) has an opening with a sealing cap at the top and its bottom is connected to the guide tube (521). The end of the guide tube (521) away from the glue container (520) is connected to the brush (522). The brush (522) is used to abut against the edge of the strip metal. The two glue containers (520) contain two components of the adhesive respectively. The two components of the adhesive are sticky after being mixed.

7. The apparatus for processing the outer conductor in a wrinkled outer conductor radio frequency coaxial feeder according to claim 1, characterized in that, The forming component (53) includes a forming cylinder (530) and a guide bar (531). The forming cylinder (530) is flared and its axial direction is set along the length direction of the operating platform (55). The larger end of the forming cylinder (530) faces the feeding end. The inner diameter of the larger end of the forming cylinder (530) is greater than the width of the strip metal. The inner diameter of the smaller end of the forming cylinder (530) is adapted to the outer diameter of the outer conductor (3). The guide bar (531) is set on the inner side wall of the forming cylinder (530). The guide bar (531) is wedge-shaped and its length direction is set along the axial direction of the forming cylinder (530). The end near the feeding end is inclined away from the axial direction of the forming cylinder (530).

8. The apparatus for processing the outer conductor in a wrinkled outer conductor radio frequency coaxial feeder according to claim 7, characterized in that, The inner diameter of the smaller end of the forming cylinder (530) is the sum of the outer diameter of the insulating layer (2) and the thickness of five times the strip metal.

9. The apparatus for processing the outer conductor in a wrinkled outer conductor radio frequency coaxial feeder according to claim 1, characterized in that, The adhesive is resistant to high temperatures, and its ambient temperature resistance is -30 ℃ to 150 ℃.

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