Radiation-resistant optical cable and manufacturing method thereof

Abstract

This invention relates to a radiation-resistant optical cable and its manufacturing method, comprising an optical fiber and a cladding. The optical fiber is a radiation-resistant fiber, covered by a tight-buffered layer, which is then covered by a PI fiber reinforcing layer. A PI film is wrapped around the PI fiber reinforcing layer, and another PI fiber outer reinforcing layer or a PI fiber outer braided reinforcing layer is wrapped around the PI film cladding. Finally, a PI film outer cladding is wrapped around the PI fiber outer reinforcing layer or the PI fiber outer braided reinforcing layer. This invention features a reasonable and simple structure; the double-layer PI fiber and PI cladding structure not only gives the optical cable excellent radiation resistance and high / low temperature resistance but also improves its mechanical strength and provides good cabling performance. The product can meet the requirements of high radiation doses and wide temperature ranges outside spacecraft cabins.

Description

Technical Field

[0001] The present invention relates to a radiation-resistant optical cable suitable for use outside a spacecraft cabin and a manufacturing method thereof, belonging to the technical field of special optical cables. Background Art

[0002] With the rapid development of optoelectronic technology, optical communication and transmission have entered more and more fields, and optical cables have also entered more application fields, including aerospace applications. In the aerospace field, due to the special use environment, the performance of optical cables needs to have wider temperature characteristics and better wiring performance than conventional communication optical cables. At the same time, they need to have space radiation resistance and vacuum resistance. However, the existing structure of optical cables is difficult to adapt to the application requirements of the above aerospace environment. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a radiation-resistant optical cable and a manufacturing method thereof in response to the above-mentioned application environment requirements. The optical cable not only has excellent radiation resistance but also has good wiring performance and temperature resistance.

[0004] The technical solution adopted by the present invention to solve the above-mentioned problems is: it includes an optical fiber and a cladding, characterized in that the optical fiber is an resistant (radiation-resistant) optical fiber, the resistant optical fiber is coated with a tight sleeve layer, the tight sleeve layer is coated with a PI fiber reinforcement layer, the PI fiber reinforcement layer is wrapped with a PI film cladding layer, the PI film cladding layer is further coated with a PI fiber outer reinforcement layer or a PI fiber outer braided reinforcement layer, and the PI film outer cladding layer is wrapped outside the PI fiber outer reinforcement layer or the PI fiber outer braided reinforcement layer.

[0005] According to the above scheme, the number of the radiation-resistant optical fibers is 1 to 3, and the radiation-resistant optical fibers are single-mode, multi-mode GI50 or multi-mode GI62.5 optical fibers; and the tight jacket layer is an acrylic resin tight jacket layer.

[0006] According to the above scheme, the PI film is a strip-shaped PI film, which is obliquely overlapped and wrapped to form a PI film wrapping layer and a PI film outer wrapping layer.

[0007] According to the above scheme, the width of the strip PI film is 0.80-5.0 mm, the thickness is 0.01-0.10 μm, and the wrapping pitch is 0.4-4.0 mm; the wrapping overlap rate of the PI film wrapping layer and the PI film outer wrapping layer is 30%-70%.

[0008] According to the above scheme, the outer diameter of the PI film wrapping layer is 0.5-3.0 mm, and the outer diameter of the PI film outer wrapping layer is 0.6-3.5 mm.

[0009] According to the above scheme, the linear density of the PI fiber is 100 dtex to 8000 dtex, and the fiber braiding pitch of the PI fiber braided reinforcement layer is 20 to 60 mm.

[0010] According to the above scheme, the additional loss of the optical cable in the 1310nm and 1550nm windows is less than or equal to 0.6dB / km within the temperature range of -100°C to +150°C.

[0011] According to the above scheme, the optical cable communicates normally under the irradiation condition of 20MRad, and the additional irradiation loss is less than or equal to 2.0dB / 100m.

[0012] The technical scheme of the production method of the present invention is as follows:

[0013] The radiation-resistant optical fiber is coated with acrylic resin and cured by ultraviolet light to produce a radiation-resistant optical fiber covered with a tight jacket layer and then drawn up.

[0014] The radiation-resistant optical fiber coated with a tight jacket layer is placed on a pay-off frame, paid out synchronously with the PI fiber, led out through a guide wheel and a line collection mold, and then wound with a PI film wrapping layer through a wrapping process;

[0015] The cable core forming the PI film wrapping layer is pulled forward and the PI fiber that is paid out is led out through a line gathering die, or an outer braided reinforcement layer of the PI fiber is woven, and finally the outer wrapping layer of the PI film is wrapped through a wrapping process.

[0016] According to the above scheme, the influence of various process parameters on the cable attenuation during the wrapping process is obtained by data fitting as follows (in this formula, each parameter is substituted with the numerical value corresponding to the following units, and the corresponding K value is calculated as a dimensionless parameter, Lg represents the logarithm with base 10, and D and p are separately explained in the embodiment):

[0017]

[0018] d: PI film wrapping layer diameter, the diameter of the sub-cable core to be wrapped, range: 0.5-3.0mm

[0019] D: PI film outer sheath diameter, finished optical cable diameter, range: 0.55-3.40mm

[0020] t: thickness of wrapping film, range: 0.01-0.10mm

[0021] b: Width of wrapping film, range: 0.80-5.0mm

[0022] p: winding pitch, range: 0.40-4.0mm

[0023] T m: Pay-off tension of wrapping film, range: 0.02-4.0N

[0024] T f :Fiber pay-off tension, range: 1.0-10.0N

[0025] C: Overlap rate: 30% to 70%

[0026] K: Additional attenuation factor of optical cable. This factor is between 0.5-7.0, and the preferred value of this factor is between 2-6. This definition range limits each wrapping process parameter.

[0027] According to the fitting formula, the additional loss after cabling is proportional to the square of the pay-off tension of the wrapping film, inversely proportional to the pay-off tension of the optical fiber, and is related to the cable core and outer diameter of the cable, as well as the thickness and width of the film. For example, the thickness and width of the film will directly affect the force of the wrapping film on the optical fiber, thereby affecting the cable attenuation index of the product. The above formula can effectively control the effect of the torsional force of the wrapping film on the optical fiber.

[0028] The above indicators are not linearly related to the additional attenuation of the optical cable, and the indicators are related to the type of optical fiber, etc. The above data fitting has a very beneficial effect on the preparation of optical cables and reducing the attenuation of the cable, and the wrapping process is successfully applied directly to the wrapping of optical cables.

[0029] The beneficial effects of the present invention are: 1. Anti-radiation optical fiber is used as the optical transmission medium, and the anti-radiation (anti-radiation) performance of the optical cable is improved by using PI fiber and PI sheath with strong anti-radiation performance and temperature resistance. The product can meet the high radiation dose and wide temperature range outside the spacecraft cabin. 2. The structural setting of the present invention is reasonable and simple. The double-layer PI fiber and PI sheath structure not only makes the optical cable have excellent radiation resistance and high and low temperature resistance, but also improves the mechanical strength of the optical cable and has good wiring performance. 3. In the process of manufacturing optical cables, the torsional force of the sheath film on the optical fiber is effectively controlled, and the cable attenuation of the optical cable is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a radial cross-sectional structural diagram of an embodiment of the present invention. Specific implementation plan

[0031] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0032] An embodiment of the present invention is Figure 1As shown, a radiation-resistant optical fiber 1 is used, and there is one optical fiber. The radiation-resistant optical fiber is coated with a tight sleeve layer 2, which is a high-temperature resistant acrylic resin tight sleeve layer with an outer diameter of 0.50 mm. A PI fiber reinforcement layer 3 is coated on the outside of the tight sleeve layer. A PI film wrapping layer 4 is wrapped around the outside of the PI fiber reinforcement layer. The PI film wrapping layer is formed by obliquely overlapping a strip of PI film and wrapping it along a spiral line. The outer diameter is controlled at 1.0 mm. A PI fiber braided reinforcement layer 5 is coated on the outside of the PI film wrapping layer. The optical cable is reinforced by PI fiber weaving, and the fiber weaving pitch is 20 mm to 60 mm. A PI film outer wrapping layer 6 is wrapped around the outside of the PI fiber braided reinforcement layer. The PI film outer wrapping layer is formed by obliquely overlapping a strip of PI film and wrapping it along a spiral line. The outer diameter is 1.80 mm. The cable loss of the optical cable is 0.42 / 0.22 dB / km (1310 / 1550 nm).

[0033] The above optical cables were subjected to irradiation tests under irradiation conditions. With the increase of irradiation dose, the additional irradiation loss continued to increase. When the total irradiation dose reached 18MRad, the additional irradiation loss of the optical cable in the 1310nm window was 1.3dB / 100m, and the additional irradiation loss in the 1550nm window was 1.8dB / 100m.

[0034] The above optical cables were subjected to temperature cycle and temperature shock tests (low temperature -100°C, high temperature +150°C) in a temperature cycle box for multiple times. Under this condition, the additional loss of the 1310nm window optical cable was 0.25dB / km@1310nm, and the additional loss of the 1550nm window optical cable was 0.28dB / km@1550nm.

[0035] The manufacturing process of this embodiment is as follows: coating the radiation-resistant optical fiber with acrylic resin, curing it through UV to make a radiation-resistant optical fiber coated with a tight sleeve layer, and then winding it; placing the radiation-resistant optical fiber coated with the tight sleeve layer on a pay-off rack, paying it out synchronously with the PI fiber, leading it out through a guide wheel and a line collection mold, and then forming a PI film sheathing layer through a wrapping process; pulling the cable core formed with the PI film sheathing layer forward through the braided PI fiber outer braided reinforcement layer, and finally wrapping it through a wrapping process to form a PI film outer sheathing layer.

[0036] The influence of various process parameters on the cable attenuation during the wrapping process is obtained by data fitting as follows (in this formula, each parameter is substituted with the numerical value corresponding to the following units, and the corresponding K value is calculated as a dimensionless parameter, Lg represents the logarithm with base 10, and D and p are separately explained in the embodiment):

[0037]

[0038] d: PI film wrapping layer diameter, the diameter of the sub-cable core to be wrapped, take 1mm,

[0039] D: PI film outer sheath diameter, finished optical cable diameter, range: 0.55-3.40mm,

[0040] t: The thickness of the wrapping film, take 0.05mm,

[0041] b: The width of the wrapping film is 2.0 mm.

[0042] p: winding pitch, range: 0.40-4.0mm,

[0043] T m : The pay-off tension of the wrapping film is 1.5N.

[0044] T f :Fiber pay-off tension, take 5N,

[0045] C: Overlap rate: 50%,

[0046] The calculated K is about 0.7

[0047] K: Additional attenuation factor of optical cable. This factor is between 0.5-7.0.

Claims

1. A radiation-resistant optical cable, comprising an optical fiber and a cladding, characterized in that The optical fiber is a radiation-resistant optical fiber, which is coated with a tight sleeve layer, which is coated with a PI fiber reinforcement layer, which is wrapped with a PI film wrapping layer, which is further coated with a PI fiber outer reinforcement layer or a PI fiber outer braided reinforcement layer, and which is wrapped with a PI film outer wrapping layer outside the PI fiber outer reinforcement layer or the PI fiber outer braided reinforcement layer.

2. The radiation-resistant optical cable according to claim 1, characterized in that The number of the radiation-resistant optical fibers is 1 to 3, and the radiation-resistant optical fibers are single-mode, multi-mode GI50 or multi-mode GI62.5 optical fibers; and the tight jacket layer is an acrylic resin tight jacket layer.

3. The radiation-resistant optical cable according to claim 1 or 2, characterized in that The PI film is a strip-shaped PI film, which is obliquely overlapped and wrapped to form a PI film wrapping layer and a PI film outer wrapping layer.

4. The radiation-resistant optical cable according to claim 3, characterized in that The width of the strip PI film is 0.80-5.0 mm, the thickness is 0.01-0.10 μm, and the wrapping pitch is 0.4-4.0 mm; the wrapping overlap rate of the PI film wrapping layer and the PI film outer wrapping layer is 30%-70%.

5. The radiation-resistant optical cable according to claim 1 or 2, characterized in that The outer diameter of the PI film wrapping layer is 0.5 to 3.0 mm, and the outer diameter of the PI film outer wrapping layer is 0.6 to 3.5 mm.

6. The radiation-resistant optical cable according to claim 1 or 2, characterized in that The linear density of the PI fiber is 100 dtex to 8000 dtex, and the fiber braiding pitch of the PI fiber braiding reinforcement layer is 20 to 60 mm.

7. The radiation-resistant optical cable according to claim 1 or 2, characterized in that The additional loss of the optical cable in the 1310nm and 1550nm windows is less than or equal to 0.6dB / km within the temperature range of -100°C to +150°C.

8. The radiation-resistant optical cable according to claim 1 or 2, characterized in that The optical cable communicates normally under the irradiation condition of 20MRad, and the additional irradiation loss is less than or equal to 2.0dB / 100m.

9. A method for manufacturing a radiation-resistant optical cable according to any one of claims 1 to 8, characterized in that The radiation-resistant optical fiber is coated with acrylic resin and cured by ultraviolet light to produce a radiation-resistant optical fiber covered with a tight jacket layer and then drawn up. The radiation-resistant optical fiber coated with a tight jacket layer is placed on a pay-off frame, and is paid out synchronously with the PI fiber, and is led out through a guide wheel and a line collection mold, and then the PI film wrapping layer is wound through a wrapping process; The cable core forming the PI film wrapping layer is pulled forward and the PI fiber that is paid out is led out through a line gathering die, or an outer braided reinforcement layer of the PI fiber is woven, and finally the outer wrapping layer of the PI film is wrapped through a wrapping process.

10. The method for manufacturing a radiation-resistant optical cable according to claim 9, characterized in that The influence of various process parameters on the cable attenuation during the wrapping process is obtained through data fitting as follows: Substitute the values ​​corresponding to the following units into each parameter and calculate the corresponding K value as a dimensionless parameter. Lg represents the logarithm with base 10; d: PI film wrapping layer diameter, the diameter of the sub-cable core to be wrapped, range: 0.5-3.0mm t: thickness of wrapping film, range: 0.01-0.10mm b: Width of wrapping film, range: 0.80-5.0mm T m : Pay-off tension of wrapping film, range: 0.02-4.0N T f :Fiber pay-off tension, range: 1.0-10.0N C: Overlap rate: 30% to 70% K: Additional attenuation factor of optical cable, which should be between 0.5-7.0.

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