Pendant head for polarization maintaining optical fiber wire falling and wire falling method

Abstract

The invention provides a pendant for a polarization maintaining optical fiber pendant and a pendant method, and belongs to the technical field of optical fiber manufacturing, the length of the pendant for the polarization maintaining optical fiber pendant is 240mm to 300mm, and the diameter of the pendant is 10mm to 12mm. The method comprises the following steps: welding a pendant at the front end of a rod head of a polarization-maintaining preform rod, wherein the pendant is the pendant for the polarization-maintaining optical fiber pendant in the first aspect; lowering the pendant and the preform to a high-temperature area; and the interior of the furnace body is heated to a set temperature, so that the pendant is fused for wire falling. According to the pendant for the polarization maintaining optical fiber wire falling, after the pendant is fused, a furnace opening cannot be blocked, and therefore normal wire falling can be guaranteed. According to the polarization maintaining optical fiber falling method, in the falling process, after the falling head is fused at a high temperature, falling is conducted through the gravity of the falling head, efficiency is high, the time of a boron rod in a high-temperature area is shortened, melting of the boron rod and deformation of the boron area are reduced, loss of the front end of a formed fiber is remarkably reduced, and the geometric structure is good.

Description

Technical Field

[0001] The invention belongs to the technical field of optical fiber manufacturing, and more specifically, relates to a polarization-maintaining optical fiber drop head and a drop method. Background Art

[0002] At present, polarization-maintaining optical fiber is drawn by fusing a conical sinker to the head of the preform rod. During the drawing process, the temperature of the drawing furnace needs to be raised to above 2100℃. After the sinker melts and falls naturally due to the high temperature, the furnace temperature is lowered to about 2000℃ to start the normal drawing process. However, this drawing process needs to last about 20 minutes. Under the action of high temperature for a long time, the boron rod inside the preform rod in the high temperature area will melt, causing the first 3km structure of the polarization-maintaining optical fiber to deform, and it cannot be regarded as a qualified product. Summary of the invention

[0003] The object of the present invention is to provide a sinker for polarization-maintaining optical fiber sinking, aiming to solve the problem that the existing optical fiber sinking takes too long.

[0004] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is to provide a polarization-maintaining optical fiber drop head and a drop method.

[0005] In a first aspect, the polarization-maintaining optical fiber drop head provided by the present invention comprises:

[0006] The length of the sinker is 240 mm to 300 mm, and the diameter of the sinker is 10 mm to 12 mm.

[0007] In a possible implementation, the sinker is made of quartz glass.

[0008] In a possible implementation, the melting point of the sinker is 1800° C. to 1900° C.

[0009] In a second aspect, the present invention provides a method for polarization-maintaining optical fiber drop, comprising the following steps:

[0010] Welding a sinker at the front end of the head of the polarization-maintaining preform rod, wherein the sinker is the sinker for polarization-maintaining optical fiber sinker as described in the first aspect;

[0011] Lower the sinker and preform rod to the high temperature area; and

[0012] The inside of the furnace is heated to a set temperature in order to melt the sinker for wire drawing.

[0013] In a possible implementation, the high temperature zone is located at a heating body inside the furnace.

[0014] In a possible implementation, heating the interior of the furnace to a set temperature so as to melt the sinker for sinking the wire includes:

[0015] The sinker is melted at the set temperature, and the wire is drawn by utilizing the gravity of the sinker.

[0016] In a possible implementation, the set temperature is 1930°C to 1970°C.

[0017] In a possible implementation manner, the polarization-maintaining preform is made of quartz glass.

[0018] In a possible implementation, welding a sinker at the front end of a polarization-maintaining preform rod head includes:

[0019] The polarization-maintaining preform rod head and the sinker are welded by using an oxyhydrogen flame welding torch.

[0020] In a possible implementation, the soldering temperature is 1900°C to 2100°C.

[0021] The beneficial effect of the sinker for polarization-maintaining optical fiber provided by the present invention is that, compared with the prior art, in the process of sinking, the sinker starts to melt in the high temperature of the furnace body, and starts to sink the wire under the action of its own gravity, and the length of the sinker is set to 240 mm to 300 mm, and the diameter is set to 10 mm to 12 mm, so that after the sinker rod is in place, the length of the sinker does not exceed the lower furnace mouth, and the diameter does not exceed the inner diameter of the annealing tube, and after the sinker is melted, the furnace mouth will not be blocked, thereby ensuring normal sinking.

[0022] The beneficial effect of the polarization-maintaining optical fiber drawing method provided by the present invention is that during the drawing process, after the sinker is melted due to high temperature, the gravity of the sinker is used to draw the fiber, which is highly efficient, reduces the time the boron rod is in the high temperature zone, reduces the melting of the boron rod and the deformation of the boron zone, significantly reduces the loss at the front end of the fiber, and has a good geometric structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 A schematic diagram of the main steps of polarization-maintaining optical fiber deflection provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0025] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0026] Reference Figure 1 Now, the polarization-maintaining optical fiber drop head and drop method provided by the present invention are described.

[0027] In the first aspect, the present embodiment provides a sinker for polarization-maintaining optical fiber wire drawing, the length of the sinker is 240mm to 300mm, and the diameter is 10mm to 12mm. In the wire drawing process, the sinker begins to melt in the high temperature of the furnace body, and begins to draw the wire under the action of its own gravity. The length of the sinker is set to 240mm to 300mm, and the diameter is set to 10mm to 12mm, so that after the sinker rod is in place, the length of the sinker does not exceed the lower furnace mouth, and the diameter does not exceed the inner diameter of the annealing tube. After the sinker melts, it will not block the furnace mouth, thereby ensuring normal wire drawing.

[0028] Optionally, the sinker is made of quartz glass. The density of quartz glass is 2.2g / cm 3 When the length of the sinker is 240mm and the diameter is 10mm, the weight of the sinker is 41.5g. When the length of the sinker is 300mm and the diameter is 12mm, the weight of the sinker is 74.6g.

[0029] Optionally, the melting point of the sinker is 1800° C. to 1900° C. After the sinker enters the high temperature zone of the furnace body, when the temperature is higher than the melting point of the sinker, the sinker begins to melt, and the wire is drawn under the gravity of the sinker itself.

[0030] During the wire drawing process, the residence time of the preform rod in the high temperature zone of the furnace body depends on the wire drawing temperature and the weight of the sinker. If the temperature is too low or the glass rod is light, the wire drawing process cannot be completed quickly, resulting in a low fiber formation rate. If the size and weight of the glass rod are too large, the melted sinker will block the furnace mouth and cause production accidents. Therefore, after the rod is in place, the length of the sinker cannot exceed the lower furnace mouth, and the diameter of the sinker cannot exceed the inner diameter of the annealing tube. The length of the sinker cannot exceed 300mm and the diameter cannot exceed 12mm. In order to ensure that the wire drawing process can be completed smoothly and quickly, the weight of the sinker needs to be guaranteed. Therefore, the length of the sinker needs to be greater than 240mm and the diameter is greater than 10mm, so as to achieve fast and smooth wire drawing.

[0031] In a second aspect, the present embodiment provides a method for polarization-maintaining optical fiber falling, the method comprising the following steps:

[0032] S1. Welding a sinker at the front end of the head of the polarization-maintaining preform rod, wherein the sinker is the sinker for polarization-maintaining optical fiber sinker as described in the first aspect.

[0033] S2. Lower the sinker and preform rod to the high temperature area of ​​the furnace.

[0034] S3. Heat the inside of the furnace to a set temperature to melt the sinker for wire drawing.

[0035] Optionally, the high temperature zone in step S2 is located at the heating body inside the furnace body. The temperature zones of the heating furnace body are not evenly distributed, and there is a high temperature zone at the location of the heating body. Generally, the front end of the rod body of the preform rod is lowered to the high temperature zone for heating and melting, and the plummet is heated and melted and falls naturally, thereby plummeting the wire.

[0036] Optionally, the furnace body is heated to a set temperature to melt the sinker for sinking the wire, including:

[0037] The sinker melts at the set temperature, and the wire is drawn by the gravity of the sinker.

[0038] Optionally, the set temperature in step S3 is 1930°C to 1970°C.

[0039] When the temperature inside the furnace reaches the set temperature, the sinker melts and begins to fall under the action of its own gravity. The whole process is shortened from the original 20 minutes to 3 minutes to 7 minutes. When the set temperature is 1930℃, the time required for the wire falling process is about 3 minutes. When the set temperature is 1950℃, the time required for the wire falling process is about 5 minutes. When the set temperature is 1970℃, the time required for the wire falling process is about 7 minutes.

[0040] Optionally, in step S1, the material of the preform rod is the same as that of the sinker, both of which are quartz glass.

[0041] Optionally, when welding the preform rod and the sinker in step S1, an oxyhydrogen flame welding torch is used to weld the preform rod and the sinker together.

[0042] Optionally, when welding the preform rod and the sinker, the welding temperature is 1900°C to 2100°C.

[0043] In a preferred embodiment, the polarization-maintaining optical fiber drop method provided in this embodiment comprises the following steps:

[0044] S1. Welding a sinker at the front end of the head of the polarization-maintaining preform rod, wherein the sinker is the sinker for polarization-maintaining optical fiber sinker as described in the first aspect.

[0045] The length of the sinker is 240mm to 300mm, and the diameter is 10mm to 12mm. During the process of sinking the wire, the sinker begins to melt in the high temperature of the furnace body, and begins to sink the wire under the action of its own gravity. The length of the sinker is set to 240mm to 300mm, and the diameter is set to 10mm to 12mm, so that after the sinker rod is in place, the length of the sinker does not exceed the lower furnace mouth, and the diameter does not exceed the inner diameter of the annealing tube. After the sinker melts, it will not block the furnace mouth, thereby ensuring normal sinking of the wire.

[0046] The material of the sinker is quartz glass. The density of quartz glass is 2.2g / cm 3 When the length of the sinker is 240mm and the diameter is 10mm, the weight of the sinker is 41.5g. When the length of the sinker is 300mm and the diameter is 12mm, the weight of the sinker is 74.6g.

[0047] The melting point of the sinker is 1800° C. to 1900° C. After the sinker enters the high temperature zone of the furnace body, when the temperature is higher than the melting point of the sinker, the sinker begins to melt, and the wire is drawn under the gravity of the sinker itself.

[0048] During the wire drawing process, the residence time of the preform rod in the high temperature zone of the furnace body depends on the wire drawing temperature and the weight of the sinker. If the temperature is too low or the glass rod is light, the wire drawing process cannot be completed quickly, resulting in a low fiber formation rate. If the size and weight of the glass rod are too large, the melted sinker will block the furnace mouth and cause production accidents. Therefore, after the rod is in place, the length of the sinker cannot exceed the lower furnace mouth, and the diameter of the sinker cannot exceed the inner diameter of the annealing tube. The length of the sinker cannot exceed 300mm and the diameter cannot exceed 12mm. In order to ensure that the wire drawing process can be completed smoothly and quickly, the weight of the sinker needs to be guaranteed. Therefore, the length of the sinker needs to be greater than 240mm and the diameter is greater than 10mm, so as to achieve fast and smooth wire drawing.

[0049] The material of the preform rod is the same as that of the sinker, which is quartz glass. When welding the preform rod and the sinker, an oxyhydrogen flame welding torch is used to weld the preform rod and the sinker together. When welding the preform rod and the sinker, the welding temperature is 1900℃ to 2100℃.

[0050] S2. Lower the sinker and preform rod to the high temperature area.

[0051] The high temperature zone is located at the heating body inside the furnace. The temperature zones of the heating furnace are not evenly distributed. There is a high temperature zone at the location of the heating body. Generally, the front end of the rod body of the preform rod is lowered to the high temperature zone for heating and melting. The plummet melts under the heat and falls naturally, thereby dropping the wire. The furnace body is heated to a set temperature so as to melt the plummet for dropping the wire, including: the plummet melts at the set temperature, and the plummet is dropped by gravity.

[0052] S3. Heat the inside of the furnace to a set temperature to melt the sinker for wire drawing.

[0053] The set temperature is 1930℃ to 1970℃. When the temperature inside the furnace reaches the set temperature, the sinker melts and begins to sink the wire under the action of its own gravity. The whole process is shortened from the original 20min to 3min to 7min. When the set temperature is 1930℃, the time required for the sinking process is about 3min. When the set temperature is 1950℃, the time required for the sinking process is about 5min. When the set temperature is 1970℃, the time required for the sinking process is about 7min.

[0054] In a preferred implementation, this embodiment provides a method for drawing a polarization-maintaining optical fiber.

[0055] At present, polarization-maintaining optical fiber is drawn by welding a conical sinker to the head of the preform rod. During the drawing process, the temperature of the drawing furnace needs to be raised to above 2100℃. After the sinker melts and falls naturally due to the high temperature, the furnace temperature is lowered to about 2000℃, and the normal drawing process begins. However, the drawing process needs to last for about 20 minutes. Under the action of high temperature for a long time, the boron rod inside the preform rod in the high temperature area will melt, causing the first 3km structure of the polarization-maintaining optical fiber to deform, and it cannot be regarded as a qualified product.

[0056] The sinker is a conical glass block welded to the front end of the polarization-maintaining optical fiber preform rod. The sinker will fall naturally when heated, achieving the purpose of wire drawing. The temperature zone of the wire drawing heating furnace is not evenly distributed. There is a high-temperature zone at the location of the heating element. Generally, the front end of the rod is lowered to the high-temperature zone for heating and melting.

[0057] The method for polarization-maintaining optical fiber falling provided in this embodiment is specifically as follows:

[0058] A glass rod with a length of 240 mm and an outer diameter of 12 mm is welded to the front end of the polarization-maintaining preform rod.

[0059] After the rod is lowered to the high temperature zone, the wire is drawn at a temperature of 1950℃.

[0060] After being melted at high temperature, the glass rod will naturally fall due to gravity, completing the fiber-falling process. The entire process is reduced from the previous 20 minutes to about 5 minutes, which greatly reduces the time the boron rod spends in the high temperature zone, reduces the melting of the boron rod and the deformation of the boron zone, significantly reduces the loss at the front end of the fiber, and has a good geometric structure.

[0061] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A sinker for polarization-maintaining optical fiber, characterized in that: The length of the sinker is 240 mm to 300 mm, and the diameter of the sinker is 10 mm to 12 mm.

2. The polarization-maintaining optical fiber sinker according to claim 1, characterized in that: The material of the sinker is quartz glass.

3. The polarization-maintaining optical fiber sinker according to claim 1, characterized in that: The melting point of the sinker is 1800°C to 1900°C.

4. A method for polarization-maintaining optical fiber drop, characterized in that: The following steps are involved: A sinker is welded at the front end of the head of the polarization-maintaining preform rod, wherein the sinker is the sinker for polarization-maintaining optical fiber as claimed in any one of claims 1 to 3; Lower the sinker and preform rod to the high temperature area; and The inside of the furnace is heated to a set temperature in order to melt the sinker for wire drawing.

5. The method for drawing a polarization-maintaining optical fiber according to claim 4, characterized in that: The high temperature zone is located at the heating body inside the furnace body.

6. The method for drawing a polarization-maintaining optical fiber according to claim 4, characterized in that: The furnace is heated to the set temperature to melt the sinker for wire drawing, including: The sinker is melted at the set temperature, and the wire is drawn by utilizing the gravity of the sinker.

7. The method for drawing a polarization-maintaining optical fiber according to claim 6, wherein: The set temperature is 1930°C to 1970°C.

8. The method for drawing a polarization-maintaining optical fiber according to claim 4, characterized in that: The polarization-maintaining preform is made of quartz glass.

9. The method for drawing a polarization-maintaining optical fiber according to claim 4, characterized in that: A sinker is welded at the front end of the polarization-maintaining prefabricated rod head, including: The polarization-maintaining preform rod head and the sinker are welded by using an oxyhydrogen flame welding torch.

10. The method for drawing a polarization-maintaining optical fiber according to claim 9, characterized in that: The soldering temperature is 1900℃ to 2100℃.

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