A kind of flexible optical cable that is suitable for using under the extreme temperature
Skill dog field
The present invention relates to a kind of communications optical cable, relate in particular to a kind of optical cable that can in more wide in range temperature range, use.
Background technology
We know, under many circumstances need (high temperature be more than 100 ℃ under extreme temperature conditions, low temperature is below-100 ℃) lay and use optical cable, for example fire detection, low-temperature (low temperature) vessel, high temperature pipe detection, the Long-distance Control of hot system, the monitoring of steam-driven generator, and in military systems such as space flight, aviation, nuclear device, under these special occasions, higher to the performance requirement that the optical cable that is applied to is high temperature resistant and low temperature resistant, otherwise the transmission quality of optical cable can not get guaranteeing.And existing communications optical cable, because the serviceability temperature of the ultra-violet curing acryl resin coating of optical fiber itself only is-50 ℃~+ 85 ℃, therefore the serviceability temperature of optical cable usually can only be in-50 ℃~+ 70 ℃ scopes, and PBT beam tube commonly used and the plastic sheath of optical cable also can't bear too high and low excessively extreme temperature, therefore, existing optical cable can't satisfy the requirement of above-mentioned use occasion.
In recent years simultaneously, various sensing optic cables have obtained the utilization of a lot of aspects.As the distributed optical fiber sensing system that utilizes optical time domain reflection (OTDR) technology particularly utilizes BOTDR (Brillouin OTDR) sensor-based system of Brillouin scattering to the susceptibility formation of fibre strain and temperature, it transmits in single-mode fiber by the Brillouin scattering that BOTDR sends, Brillouin scattering when utilizing single-mode fiber to be subjected to stress or temperature variation in the optical fiber will produce the principle of frequency displacement, calculate optical fiber the numerical value of strained and temperature; Equally, in the ROTDR that susceptibility constituted (RamanOTDR) sensor-based system that utilizes Raman diffused light to fiber optic temperature, also use multimode optical fiber as temperature-sensing element; In addition, in the phase modulation (PM) distributed optical fiber vibration sensing positioning system that Mach-Ze De (Mach-Zehnder) type fibre optic interferometer constitutes, also need be with single-mode fiber as the vibrating sensing element.Various sensing optic cables as said temperature, vibration sensing system also can lay under extreme temperature and use, and therefore, need optical cable to have the better temperature resistance energy.
In addition,,, certainly will influence the crooking ability of optical cable like this, especially under extreme temperature conditions, lay and use in various occasions thereby influenced optical cable as strengthening steel wire or FRP etc. owing to be provided with the anti-element of opening that strengthens rigidity in the conventional cable usually.
Summary of the invention
The object of the invention is exactly that a kind of flexible optical cable that can use and have good bending property in-150 ℃~+ 300 ℃ temperature ranges is provided in order to overcome the deficiencies in the prior art.
In order to reach the foregoing invention purpose, technical scheme of the present invention is: a kind of flexible optical cable that is suitable for using under the extreme temperature, it comprises the oversheath mutually sheathed successively from skin to nexine, steel wire braid, metal teleflex, be provided with at least one optical fiber in the described metal teleflex, and every described optical fiber comprises fibre core, is coated on the fibre cladding and the polyimide coating of described fibre core periphery successively.
To the variation of technique scheme be explained as follows:
1, described metal teleflex is formed by sheet metal phase helically coiling; thereby make metal teleflex of the present invention to carry out outside the particularly resistance to compression protection of machinery to optical fiber; the structure of its helically coiling makes that whole optical cable is more pliable and tougher; has good bending property; and further; described sheet metal width is that 1mm~3mm, thickness are 0.1mm~0.3mm, and the sheet metal material is a stainless steel.
2, also be enclosed with the carbon sealant between the fibre cladding of described optical fiber and the polyimide coating,,, can prevent the erosion of moisture optical fiber by the hydroscopicity of carbon by this carbon sealant is set.
3, described steel wire braid is formed by the finer wire braiding of plating zinc on surface.
4, described oversheath has the organdy braiding of polyimide resin to form by dip-coating; the oversheath that the organdy that soaked with polyimide resin weaves has replaced conventional plastic casing; not only strengthened the machinery and the chemoproection effect of optical cable, and guaranteed that further optical cable can use in wider temperature range.
Because the utilization of technique scheme, the present invention compared with prior art has following advantage: optical cable of the present invention is the central beam tube type optical cable, in the time of can guaranteeing that like this optical cable is crooked, and the deformation minimum that optical fiber bundle tubes bears; Because its fibre coating adopts polyimide coating, thereby can guarantee optical fiber long-term use in-180 ℃~+ 300 ℃ temperature ranges; Adopt metal hose to carry out particularly resistance to compression protection of machinery simultaneously, and good bending property is arranged optical fiber; Steel wire braid outside metal hose, it is to be formed by the finer wire braiding, in cable configuration of the present invention, form the anti-element of opening, having replaced conventional cable adopts reinforcement steel wire or FRP etc. as reinforcing element, thereby make the optical cable bending property be further enhanced, therefore, optical cable of the present invention be suitable under extreme temperature, laying and the occasion used and indoor, machine room, equipment in the application of the especially little occasion of various requirement bending radius such as connect.
Description of drawings
Accompanying drawing 1 is cable configuration synoptic diagram of the present invention;
Accompanying drawing 2 is optical fiber structure synoptic diagram of the present invention;
Wherein: 1, optical fiber; 11, fibre core; 12, fibre cladding; 13, carbon sealant; 14, polyimide coating; 2, metal teleflex; 3, steel wire braid; 4, oversheath.
Embodiment
Below in conjunction with accompanying drawing the preferred embodiment of the invention is elaborated:
Optical cable as shown in Figure 1; comprise the optical fiber 1 that is positioned at the center; the optical fiber 1 outer metal teleflex 2 that is provided with; optical fiber 1 penetrates and constitutes optical fiber bundle tubes in the metal teleflex 2; metal teleflex 2 outer walls are coated with steel wire braid 3; the steel wire braid 3 outer oversheaths 4 that are with; wherein; described metal teleflex 2 is formed by the sheet metal helically coiling; in the present embodiment; sheet metal adopts stainless steel substrates, and the width * thickness of stainless steel substrates is 1.5 * 0.2mm, and following table has provided some reference datas of metal teleflex; but this list data can not play the qualification to structure of the present invention; optical fiber 1 is placed in this metal hose 2, not only can be subjected to favorable mechanical and protect particularly resistance to compression protection, and make optical cable have good bending property.
The specification of metal teleflex 2 is as shown in the table:
Described steel wire braid 3 is to be formed by the finer wire braiding, and steel wire can adopt the zinc plated mild carbon steel silk, the anti-element of opening of steel wire braid 3 conduct in this cable configuration.Oversheath 4 forms by the organdy establishment and with the polyimide resin dip-coating; because polyimide has higher decomposition temperature; (generally all about 500 ℃) and resistance to low temperature (as can embrittlement in-269 ℃ liquid helium); it can form favorable mechanical and chemoproection effect to optical cable, and can work in-180 ℃~+ 300 ℃ temperature ranges.
As shown in Figure 2, described optical fiber 1 comprises fibre cladding 12 and the fibre cladding 12 outer polyimide coatings 14 that apply outside fiber core 11, the fiber core 11, also is provided with carbon sealant 13 between fibre cladding 12 and fibre coating 14.Because it is polyimide that the coating material of outer fiber adopts,, thereby can guarantee optical fiber long-term use in-180 ℃~+ 300 ℃ temperature ranges.Simultaneously one deck carbon sealant 13 is set outside fibre cladding 12, can prevents the erosion action of moisture optical fiber.In the present invention, optical fiber can adopt multimode or single-mode fiber according to request for utilization, when bending property being required when high, can adopt the G of loss bend-insensitive, 657 optical fiber.In concrete the manufacturing, the optical fiber in the metal teleflex can be provided with certain surplus length, is not subjected to the effect of extra-stress to guarantee optical cable optical fiber when laying and use.And the quantity of optical fiber 1 can be 1~8, but not and be limited to this quantity.
When processing optical cable of the present invention, the method that optical fiber 1 penetrates in the metal hose 2 can adopt following two kinds; The one, according to the different mining of fiber number, stainless steel soft bore and length with methods such as vibratory drilling method, plunging, vacuum suctions, the 2nd, the moulding of stainless steel sheet| corrugated hose is directly carried out outside optical fiber.
And in the metal teleflex of optical cable of the present invention, do not have the filling ointment, thereby help the cable laying operation of optical cable, also help use as temperature, vibrating sensing optical cable.Particularly as the use of vibrating sensing optical cable the time, this optical cable does not have the architectural feature of ointment, owing to avoided in the traditional fiber beam tube ointment to the damping action of fiber-optic vibration, thus make optical fiber have maximum vibration sensitivity.