CN219217853U - Preform heater and preform resistance wire drawing furnace device - Google Patents

Abstract

The application relates to a preform heater and a preform resistance wire drawing furnace device. The heating main body comprises a plurality of strip-shaped resistors which are arranged at intervals along the circumferential direction, two ends of each strip-shaped resistor are respectively connected with the strip-shaped resistors positioned at two sides of the strip-shaped resistor, the value range of the inner diameter of the heating main body is 230-260 mm, the connection parts of the strip-shaped resistors are at least partially thickened, and the connection parts and the strip-shaped resistors are configured to enable the value range of the normal-temperature resistance value of the heating main body to be 40-49 mΩ. The heater for the optical fiber preform rod can meet the heating and drawing requirements of the optical fiber preform rod with large diameter, deformation is easy to occur during high-temperature heating due to the large inner diameter of the heater, the stability of the whole structure of the heater can be improved due to the thickening design of the connecting part of the strip resistor, and the connecting part and the strip resistor are matched through materials or structures, so that the normal-temperature resistance value of the large-volume heater can be reduced, the power output value of a power supply during heating is ensured, and the drawing effect is ensured.

Description

Preform heater and preform resistance wire drawing furnace device

Technical Field

The application relates to the field of optical fiber communication, in particular to a preform heater and a preform resistance wire drawing furnace device.

Background

At present, the optical fiber is used as a unique information carrier for optical communication transmission, has the advantages of small attenuation, high bandwidth, stable transmission and the like, is widely used for information transmission, and is subjected to high-temperature heating and melting through a drawing furnace to finish the drawing and fiber forming process. The common diameter of the optical fiber preform is 120-160 mm, the length of single drawing is 8-14 h, the number of drawing mileage is 1800-2500 km, and the single drawing yield changing time is 2.5 h/time because the frequency of changing production is high due to low drawing mileage, so the drawing productivity is limited.

The most effective method for reducing the production cost of the optical fiber is to improve the production efficiency, and besides the conventional reduction of equipment faults and the improvement of the running time of equipment, the improvement of the optical rod drawing mileage is the most direct and effective mode. In the related art, there are two directions for improving the drawing mileage, namely, increasing the diameter of the preform, and secondly, lengthening the length of the preform, along with the development of optical fiber technology, the drawing of a large-diameter preform in the field of optical fiber drawing gradually becomes a trend, so as to seek to greatly reduce the optical fiber drawing cost and improve the manufacturing efficiency of drawing equipment.

However, as the diameter of the optical fiber preform increases, the drawing furnace requires a larger structural size and a larger power to ensure melting of the optical fiber preform, however, the large power will cause problems of deformation and blowing of the heater, which adversely affects the performance and parameter index of the optical fiber.

Disclosure of Invention

The embodiment of the application provides a preform heater, which aims to solve the problem that a heater is easy to deform and blow when a drawing furnace in the related art draws an optical fiber preform with a large diameter.

In a first aspect, a preform resistance wire drawing furnace apparatus is provided, comprising:

the heating main body comprises a plurality of strip-shaped resistors which are arranged at intervals along the circumferential direction, wherein two ends of each strip-shaped resistor are respectively connected with the strip-shaped resistors at two sides of the strip-shaped resistor, the value range of the inner diameter of the heating main body is 230-260 mm, the connection parts of the strip-shaped resistors are at least partially thickened, and the connection parts and the strip-shaped resistors are configured to enable the value range of the normal-temperature resistance value of the heating main body to be 40-49 mΩ.

In some embodiments, the material of the junction and/or the strip resistor has a resistivity of 10 to 13mΩ.

In some embodiments, the thickness of the thickened region of the junction is 2-6 mm thicker than the thickness of the strip resistor.

In some embodiments, the heating body has a height dimension of 130 to 160mm.

In some embodiments, the thickened regions of the junction each extend toward both sides to at least partially overlap the ends of the strip resistor on both sides thereof.

In a second aspect, the present application provides a preform resistance wire drawing furnace device, comprising: the furnace body is internally provided with the preform heater.

In some embodiments, the two ends of the furnace body are respectively provided with an air outlet and an air inlet, the air inlet is used for supplying mixed gas to the bottom of the muffle tube of the furnace body, and the air outlet is used for discharging the mixed gas through the top of the muffle tube.

In some embodiments, the muffle tube is tapered from 20mm to 60mm away from the bottom, with the taper decreasing from top to bottom.

In some embodiments, the furnace body further comprises an air inlet cover plate, the air inlet cover plate is annular, a plurality of air inlet holes are formed in the side face at intervals along the circumferential direction, and the air inlet holes are used for supplying sealing gas to flow in so as to form a seal above the muffle tube.

In some embodiments, the furnace body further comprises an extension tube arranged below the muffle tube and the air inlet, and the length dimension of the extension tube is 2-4 m.

The beneficial effects that technical scheme that this application provided brought include:

the embodiment of the application provides a prefabricated rod heater, because the heating main body includes a plurality of strip resistances that set up along circumference interval, the both ends of strip resistance link to each other with the strip resistance that is located its both sides respectively, and make the value range of heating main body's internal diameter be 230 ~ 260mm, the junction of strip resistance all is partly thickened simultaneously, and make junction and strip resistance be configured to make the value range of heating main body's normal atmospheric temperature resistance value be 40 ~ 49mΩ, the value range of this prefabricated rod heater's internal diameter is 230 ~ 260mm, can satisfy the heating drawing of large-diameter optical fiber perform, secondly, because the internal diameter size of heater is bigger, deformation takes place more easily during the high temperature heating, and the design that strip resistance junction carries out thickening just can increase the stability of heater overall structure, avoid deformation, finally junction and strip resistance pass through the cooperation of material or structure, make the normal temperature resistance value of bulky heater can reduce to 40 ~ 49mΩ, thereby the size of power output value when guaranteeing heating, provide sufficient heat for the prefabricated rod of large-diameter, guarantee drawing effect.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of a preform heater according to an embodiment of the present disclosure;

fig. 2 is a schematic structural diagram of a resistance drawing furnace device for a preform according to an embodiment of the present application.

In the figure: 1-heating main body, 10-strip resistor, 11-junction, 2-furnace body, 20-exhaust port, 21-air inlet, 22-muffle tube, 23-air inlet cover plate, 230-air inlet, 24-extension tube, 3-connecting ear and 4-optical fiber preform.

Detailed Description

For the purposes of making the objects, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present application based on the embodiments herein.

The embodiment of the application provides a preform heater, which can solve the problem that a heater is easy to deform and blow when a drawing furnace in the related art draws an optical fiber preform with a large diameter.

Referring to fig. 1, the preform heater mainly includes a heating body 1, where the heating body 1 includes a plurality of strip resistors 10 disposed at intervals along a circumferential direction, two ends of the strip resistor 10 are respectively connected to the strip resistors 10 disposed at two sides thereof, that is, one end of each strip resistor 10 is connected to a corresponding end of the strip resistor 10 disposed at one side thereof, and the other end is connected to a corresponding end of the strip resistor 10 disposed at the other side thereof, and the ends are connected to form a closed loop, so that the value range of the inner diameter of the heating body 1 is 230-260 mm, which is larger than the inner diameter size of a conventional preform heater, and can satisfy the heating drawing of a large-diameter optical fiber preform 4 with a value range of 170-230 mm; the connecting parts 11 of the strip resistors 10 are at least partially thickened, and as the connecting parts 11 of different strip resistors 10 are all curved cambered surfaces during heating, current concentration easily occurs at the connecting parts, so that the position is excessively loaded and is broken and deformed for a long time, the thickened design can just seal the defect at the connecting parts, the stability of the overall structure of the heater is improved, and the deformation of the heater of the preform at high temperature is avoided; because the requirement of the large-diameter preform on temperature is higher during drawing, the power of the power supply cannot output a required value after the resistance of the heater is too high, and the heating of the heater is affected, and the heater can increase the whole normal-temperature resistance value to a certain extent although the connecting part 11 is thickened, the aim of reducing the material consumption and reducing the normal-temperature resistance can be fulfilled by adjusting the structures such as gaps among the strip-shaped resistors 10, and the like, therefore, the connecting part 11 and the strip-shaped resistors 10 are configured to ensure that the normal-temperature resistance value of the heating main body 1 is 40-49 mΩ, the power output value of the power supply is ensured during heating, enough heat is provided for the large-diameter optical fiber preform 4, and the drawing effect is ensured.

Further, the materials of the strip resistor 10 and the connection portion 11 are both graphite materials, and besides the purpose of reducing the normal temperature resistance by reducing the material consumption by adjusting the structures such as the gap between the strip resistors 10, the purpose of adjusting the overall normal temperature resistance of the heater can be achieved by changing the resistivity of the materials of the connection portion 11 and the strip resistor 10, preferably, in this embodiment, the resistivity of the materials of the connection portion 11 and the strip resistor 10 is 10 to 13mΩ. The number of the strip resistors 10 is 18 to 24.

Further, the thickness of the thickened area of the connection part 11 is 2-6 mm thicker than the thickness of the strip resistor 10. Specifically, the purpose of the region of the thickened junction 11 is to strengthen the connection stability between the two strip resistors 10, so that the thickened direction of the junction 11 can extend outwards along the outer wall or inwards along the inner wall, in this embodiment, preferably, the thickened direction of the thickened region of the junction 11 extends outwards along the outer wall, and damage to the muffle tube and other components caused by extrusion when the thickened region extends inwards along the inner wall can be effectively avoided.

Further, since the present preform heater is suitable for drawing the large-diameter optical fiber preform 4, it is required to have a height dimension of 130 to 160mm in addition to an inner diameter of 230 to 260mm, and the height dimension of the heating body 1 in this embodiment is also required.

Further, the thickening of the connection portion 11 is mainly to increase the structural strength of the connection portion 11, and the shape of the thickened area of the connection portion 11 may be circular, elliptical or square, or may be other suitable shape; in order to ensure the stability of the connection, the thickened areas of the connection 11 extend towards both sides so as to overlap at least partially the corresponding ends of the strip-shaped resistor 10 located on both sides thereof, in which embodiment, it is preferred that the shape of the thickened areas of the connection 11 is preferably square, where square means that the projection along the vertical plane is square, since the thickened areas are, whatever their shape, distributed in the circumferential direction and then are curved overall; secondly, in this embodiment, in order to ensure the connection stability, the thickened areas of the connection 11 extend toward both sides until they are flush with the vertically disposed sides of the strip resistor 10 on both sides.

Further, the preform heater further comprises connecting lugs 3, wherein the number of the connecting lugs 3 is at least two, and the connecting lugs are arranged at intervals along the circumferential direction and used for fixing the preform heater with the furnace body 2.

The utility model also provides a perform resistance wire drawing furnace device, see the figure 2 and show, this perform resistance wire drawing furnace device mainly includes furnace body 2, be equipped with the perform heater in the furnace body 2 for satisfy the drawing of the optical fiber perform 4 of major diameter.

Further, the two ends of the furnace body 2 are respectively provided with an air outlet 20 and an air inlet 21, the air inlet 21 is used for supplying mixed gas to the bottom of a muffle tube 22 of the furnace body 2, the air outlet 20 is used for discharging the mixed gas through the top of the muffle tube 22, that is, the positions of the air outlet 20 and the air inlet 21 correspond to the top and the bottom of the muffle tube 22, the furnace body 2 is protected by introducing protective gas and exhausting the protective gas in an air inlet upper exhaust mode below, and other structures except for a heater in the furnace body 2 are all insulated by adopting heat insulation materials.

Further, the muffle tube 22 is a conical structure with a gradually smaller size from top to bottom at a distance of 20-60 mm from the bottom, the specific angle of the conical structure can be adjusted according to actual production requirements, and the design of the conical structure can effectively reduce the vortex structure formed by gas in the furnace body 2 so as to improve the wire drawing stability.

Further, the furnace body 2 further includes an air inlet cover plate 23, the air inlet cover plate 23 is annular, and a plurality of air inlet holes 230 are arranged on the side surface at intervals along the circumferential direction, and the air inlet holes 230 are used for introducing sealing gas to form a seal above the muffle tube 22; wherein the shielding gas is helium and argon, and the gas used for sealing is helium.

Further, the furnace body 2 further comprises an extension tube 24 arranged below the muffle tube 22 and the air inlet 21, the length dimension of the extension tube 24 is 2-4 m, the extension tube 24 can ensure that the temperature of bare fibers is gradually reduced, rapid quenching is avoided, a certain transition is provided, and excessive internal stress of drawn optical fibers is avoided.

The embodiment of the resistance wire drawing furnace device for the optical fiber preform rod with different diameters is as follows:

when the optical fiber preform 4 with the diameter of 170mm is drawn, the height dimension of the preform heater is 130mm, the inner diameter is 230mm, the room temperature resistance is 40mΩ, the number of the strip resistors 10 is 18, and the thickness of the thickened area of the joint 11 is 2mm; the height of the conical structure at the bottom of the tube was 20mm and the length of the extension tube 24 was 2m. In the specific drawing, the gas process parameters in the furnace body 2 are helium gas 6L/min, argon gas 1L/min, exhaust gas 15L/min and sealing gas helium gas 4L/min in the protective gas, and indexes such as the out-of-roundness, strength and the like of the cladding of the drawn optical fiber meet the requirements after the optical fiber preform 4 with the thickness of 170mm is drawn.

When an optical fiber preform 4 having a diameter of 200mm is drawn, the height dimension of the preform heater is 145mm, the inner diameter is 245mm, the room temperature resistance is 45mΩ, the number of the strip-shaped resistors 10 is 22, and the thickness of the thickened region of the junction 11 is 4mm; the height of the conical structure at the bottom of the tube was 40mm and the length of the extension tube 24 was 3m. In the specific drawing, the gas process parameters in the furnace body 2 are helium gas 8L/min, argon gas 2L/min and exhaust gas 16L/min in the protective gas, sealing gas helium gas 4L/min, and indexes such as the out-of-roundness, strength and the like of the cladding of the drawn optical fiber meet the requirements after the optical fiber preform 4 with 200mm is drawn.

When the optical fiber preform 4 with the diameter of 230mm is drawn, the height dimension of the preform heater is 160mm, the inner diameter is 260mm, the room temperature resistance is 49mΩ, the number of the strip resistors 10 is 24, and the thickness of the thickened area of the joint 11 is 6mm; the height of the conical structure at the bottom of the tube was 60mm and the length of the extension tube 24 was 4m. In the specific drawing, the gas process parameters in the furnace body 2 are helium gas 10L/min, argon gas 3L/min and exhaust gas 16L/min in the protective gas, sealing gas helium gas 4L/min, and indexes such as the out-of-roundness, strength and the like of the cladding of the drawn optical fiber meet the requirements after the optical fiber preform 4 with the thickness of 230mm is drawn.

In the description of the present application, it should be noted that the azimuth or positional relationship indicated by the terms "upper", "lower", etc. are based on the azimuth or positional relationship shown in the drawings, and are merely for convenience of description of the present application and simplification of the description, and are not indicative or implying that the apparatus or element in question must have a specific azimuth, be configured and operated in a specific azimuth, and thus should not be construed as limiting the present application. Unless specifically stated or limited otherwise, the terms "mounted," "connected," and "coupled" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art as the case may be.

It should be noted that in this application, relational terms such as "first" and "second" and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The foregoing is merely a specific embodiment of the application to enable one skilled in the art to understand or practice the application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. A preform heater, comprising:

the heating main body (1) comprises a plurality of strip-shaped resistors (10) which are arranged at intervals along the circumferential direction, wherein two ends of each strip-shaped resistor (10) are respectively connected with the strip-shaped resistors (10) at two sides of the strip-shaped resistor, the value range of the inner diameter of the heating main body (1) is 230-260 mm, the connecting parts (11) of the strip-shaped resistors (10) are at least partially thickened, and the connecting parts (11) and the strip-shaped resistors (10) are configured to enable the value range of the normal-temperature resistance value of the heating main body (1) to be 40-49 mΩ.

2. A preform heater as claimed in claim 1, wherein:

the resistivity of the material of the connection (11) and/or the strip resistor (10) is 10-13 mΩ.

3. A preform heater as claimed in claim 1, wherein:

the thickness of the thickened area of the connecting part (11) is 2-6 mm thicker than the thickness of the strip resistor (10).

4. A preform heater as claimed in claim 1, wherein:

the height dimension of the heating main body (1) is 130-160 mm.

5. A preform heater as claimed in claim 1, wherein:

the thickened areas of the junction (11) extend towards both sides to at least partially overlap the ends of the strip resistor (10) on both sides thereof.

6. A preform resistance wire drawing furnace device, characterized in that it comprises: a furnace body (2), wherein the furnace body (2) is internally provided with the preform heater as claimed in claim 1.

7. A preform resistance wire drawing furnace apparatus as defined in claim 6, wherein:

the two ends of the furnace body (2) are respectively provided with an exhaust port (20) and an air inlet (21), the air inlet (21) is used for supplying mixed gas to the bottom of a muffle tube (22) of the furnace body (2), and the exhaust port (20) is used for exhausting the mixed gas through the top of the muffle tube (22).

8. A preform resistance wire drawing furnace apparatus as defined in claim 7, wherein:

the muffle tube (22) is in a conical structure with a distance of 20-60 mm from the bottom end, and the size of the muffle tube is gradually reduced from top to bottom.

9. A preform resistance wire drawing furnace apparatus as defined in claim 7, wherein:

the furnace body (2) further comprises an air inlet cover plate (23), the air inlet cover plate (23) is annular, a plurality of air inlet holes (230) are formed in the side face at intervals along the circumferential direction, and the air inlet holes (230) are used for supplying sealing gas to flow in so as to form sealing above the muffle tube (22).

10. A preform resistance wire drawing furnace apparatus as defined in claim 7, wherein:

the furnace body (2) further comprises an extension tube (24) arranged below the muffle tube (22) and the air inlet (21), and the length dimension of the extension tube (24) is 2-4 m.

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