CN115793165A

CN115793165A - Rat-proof optical cable with color-bar composite outer sheath and preparation method thereof

Info

Publication number: CN115793165A
Application number: CN202211585219.3A
Authority: CN
Inventors: 李红艳; 杜超; 曾鹏程; 马波; 刘喆驰; 孟泉
Original assignee: Yangtze Optical Fibre and Cable Co Ltd
Current assignee: Yangtze Optical Fibre and Cable Co Ltd
Priority date: 2022-12-09
Filing date: 2022-12-09
Publication date: 2023-03-14

Abstract

The invention discloses a ratproof optical cable with a color bar composite outer sheath and a preparation method thereof, wherein the ratproof optical cable is provided with an inner PE sheath, an outer nylon sheath and an outer nylon color bar composite outer sheath which are tightly combined; the composite outer sheath is formed at one time by adopting a three-layer co-extrusion process; the PE material forming the inner PE sheath contains maleic anhydride; wherein the weight ratio is as follows: maleic anhydride, PE = 18-20; the nylon material forming the outer nylon sheath is a black nylon 12 material; the nylon material for forming the outer layer nylon color strips is a nylon 12 material containing color master batches in a preset proportion. According to the preparation method of the ratproof optical cable with the color bar composite outer sheath, the sheath is formed in one step by adopting a three-layer co-extrusion process, and maleic anhydride is added into the PE material of the inner sheath in production, so that the inner PE sheath and the outer nylon sheath are not easy to separate, the color bars formed by the nylon 12 material containing the color master in a preset proportion are not easy to fall off, the color bars can be effectively prevented from falling off, and the ratproof optical cable with the color bar composite outer sheath has the performance of ratproof and easy identification.

Description

Ratproof optical cable with color-strip composite outer sheath and preparation method thereof

Technical Field

The invention belongs to the field of optical cable manufacturing, and particularly relates to a ratproof optical cable with a color-strip composite outer sheath and a preparation method thereof.

Background

With the rapid development of communication technology, the laying of communication optical cables in long-distance pipelines is more and more common, and in the use process of the optical cables, the optical cables exposed outside are usually bitten by rodents, so that the optical cables are easily physically damaged, the outer sheaths are further damaged, and the risk that the optical cables are broken due to the fact that the large-area damage of the outer sheaths and the loss of protection occurs in the optical cables exists. The existing optical cable is mainly used for preventing rats from damaging the optical cable by enhancing the mechanical strength of an outer sheath or adding a chemical rat repellent. Although the existing rat-proof optical cable is also widely applied to optical communication lines, the situation that the optical cable is bitten off by rats still frequently occurs, and regular maintenance of the optical cable is an important means for avoiding the optical cable from being bitten off by rats.

The sheath used as a protective layer of the optical cable for resisting various external special complex environments has to have excellent mechanical property, environment resistance, chemical corrosion resistance and the like, the commonly used sheath material at present is PE material, but the single-layer sheath has poor rat-proof effect, the existing rat-proof optical cable generally adopts a composite outer sheath, the inner layer is a PE sheath, and the outer layer is a nylon sheath. Nylon has high strength and high toughness, is an ideal optical cable outer sheath material, has the functions of preventing termites and mice, and is commonly used for manufacturing the outer sheath of the ratproof optical cable.

At present in long defeated pipe work, protection against rodents optical cable generally constructs with the pipeline synchronization, lays with the ditch, and it lays with the ditch to be many optical cables in addition generally, and the protection against rodents optical cable of outdoor laying is generally black, when needing the maintenance at protection against rodents optical cable, is difficult to discern the optical cable that needs to maintain under the complex environment fast. At present, a color bar is added on the outer sheath of the rat-proof optical cable to mark the optical cable. However, the bonding strength between the color bar and the jacket is insufficient due to the incompleteness of the color bar itself, and the color bar may fall off after the color bar is laid. Especially nylon sheath, the color bar often drops, still is difficult to discern the optical cable that needs to maintain when maintaining. Therefore, the problem that the color strips on the outer sheath fall off is urgently needed to be solved at present, and particularly, the color strips on the commonly used composite outer sheath are easy to fall off.

Disclosure of Invention

Aiming at the defects or improvement requirements of the prior art, the invention provides a ratproof optical cable with a color-strip composite outer sheath and a preparation method thereof, and aims to add maleic anhydride into a PE material for forming an inner-layer PE sheath, co-extrude the maleic anhydride with a nylon material for forming an outer-layer nylon sheath and a nylon 12 material for forming an outer-layer nylon color strip, extrude and wrap the PE + nylon + color strip on the outermost layer of the optical cable to form the composite outer sheath in one step, and fix the color strip on the surface of the outer-layer nylon sheath, thereby solving the technical problem that the color strip on the surface of the conventional ratproof optical cable composite outer sheath is easy to fall off.

To achieve the above object, according to one aspect of the present invention, there is provided a ratproof optical cable having a color-stripe composite outer sheath, the ratproof optical cable having an inner PE sheath, an outer nylon sheath, and an outer nylon color-stripe composite outer sheath which are tightly combined;

the composite outer sheath is formed at one time by adopting a three-layer co-extrusion process;

the PE material forming the inner PE sheath contains maleic anhydride; wherein the weight ratio is as follows: maleic anhydride, PE = 18-20;

the nylon material forming the outer nylon sheath is a black nylon 12 material;

the nylon material for forming the outer layer nylon color strips is a nylon 12 material containing color master batches in a preset proportion.

Preferably, the ratproof optical cable with the color bar composite outer sheath has maleic anhydride HDPE = 18.

Preferably, the PE material of the ratproof optical cable with the color-stripe composite outer sheath is high-density polyethylene.

Preferably, the rat-proof optical cable with the color-strip composite outer sheath has the advantage that the color master in the nylon material forming the outer nylon color strip accounts for 3-4% of the mass of the nylon 12 pigment.

Preferably, the rat-proof optical cable with the color-strip composite outer sheath has the advantage that the color master in the nylon material forming the outer nylon color strip accounts for 3% of the mass of the nylon 12 pigment.

Preferably, the ratproof optical cable with the color bar composite outer sheath comprises a cable core; the cable core comprises a layer-twisted cable core and a stainless steel belt; the layer-stranded cable core is formed by stranding a non-metal central reinforcing piece and a full-dry type sleeve into a full-dry type cable core, and a plurality of optical fibers are arranged in the full-dry type sleeve; the outer layer of the layer-stranded cable core is longitudinally wrapped with a stainless steel band, and the stainless steel band is provided with an open mooring rope.

According to another aspect of the invention, the invention also provides a preparation method of the ratproof optical cable with the color-bar composite outer sheath, which comprises the following steps:

acquiring a cable core to be sheathed;

a sheath is formed at one time outside the cable core by adopting a three-layer co-extrusion process;

the nylon material forming the outer nylon sheath is a black nylon 12 material;

Preferably, in the preparation method of the ratproof optical cable with the color bar composite outer sheath, the three-layer co-extrusion process adopts a single machine head to connect 3 plastic extruders to form the sheath at one time, and specifically comprises the following steps:

(1) The host machine adds the PE material forming the inner layer PE sheath, the material drying temperature is 70 ℃, the host machine temperature zone comprises 5 temperature zones of the machine chamber and 4 temperature zones of the machine head, and the processing temperatures are sequentially set in the machine cavity temperature zone of the temperature control interface of the extruding machine from left to right as follows: 160/180/190/200/210, DEG C, and the processing temperatures of the machine head temperature zone are set from left to right in sequence as follows: 220/230/230/230, deg.C;

(2) The nylon material of outer nylon sheath is added to fixed color bar machine and is formed, and material drying temperature is 100 ℃, and fixed color bar machine warm area includes 5 warm areas of machine thorax and 4 warm areas of aircraft nose, and the machine chamber warm area at extruding machine temperature control interface from left to right sets gradually the processing temperature and is: 205/225/225/230/230, and the processing temperature of the machine head temperature zone is set to 225/225/220/220, and the temperature is set to be DEG C from left to right; additionally, a movable auxiliary material drying machine is adopted to preheat the nylon material, and the material drying temperature is 100 ℃;

(3) Adding a nylon material for forming the outer-layer nylon color strips into the movable color strip machine, wherein the material drying temperature is 70 ℃, the temperature zone of the movable color strip machine comprises 3 temperature zones of a machine chamber and 2 temperature zones of a machine head, and the processing temperature is 190/200/225 ℃ from left to right in the machine cavity temperature zone of the temperature control interface of the extruding machine; the processing temperature of the machine head temperature zone is 225/225℃, and the drying material temperature is 70 ℃ from left to right; and a nylon special screw is used, and the screw is numbered: sm-22201JH 220704-03.

Preferably, in the preparation method of the ratproof optical cable with the color bar composite outer sheath, the PE material forming the inner PE sheath is HDPE containing maleic anhydride, and the preferred mass ratio is as follows: maleic anhydride HDPE = 18.

Preferably, in the preparation method of the ratproof optical cable with the color-strip composite outer sheath, the nylon material for forming the outer layer nylon color strip is prepared from the following raw materials in parts by weight, wherein the ratio of the color master to the nylon 12 pigment is 3-4.

In general, compared with the prior art, the above technical solution contemplated by the present invention can achieve the following beneficial effects:

according to the rat-proof optical cable with the colored-bar composite outer sheath, the colored bars are arranged on the surface of the outer sheath, so that the rat-proof optical cable is easy to identify, the optical cable needing to be maintained can be quickly identified in a complex environment, and the rat is prevented from further biting to cause the optical cable to be bitten and broken to influence communication. Add maleic anhydride in the PE material that forms the inlayer PE sheath, with the nylon material that forms outer nylon sheath and the nylon material that forms outer nylon color bar are crowded altogether, and strict control dries by fire material temperature and crowded material temperature one shot forming sheath, does benefit to and forms fixed color bar and inlayer PE sheath and the difficult layering of outer nylon sheath on outer nylon sheath surface, the nylon 12 material of nylon 12 material for containing the look female of predetermined proportion of nylon material that forms outer nylon color bar, nylon 12 this colouring material is joined in marriage the nylon 12 look female of predetermined proportion, and this kind of color bar sample is difficult for delaminating with the nylon sheath, can further prevent that the color bar from droing.

Further, the rat-proof optical cable with the color-bar composite outer sheath is prepared by the preparation method provided by the invention, the sheath is formed at one time by adopting a three-layer co-extrusion process, the PE + nylon + color-bar one-time-formed outer sheath is extruded on the outermost layer of the cable core, and particularly when the maleic anhydride is HDPE =18, the PE sheath on the inner layer and the nylon sheath on the outer layer in the composite outer sheath are not easy to be layered, the surface is smooth, the rat-proof optical cable can have the characteristics of air blowing performance, rat prevention and easy identification, and the application range is wide.

Drawings

FIG. 1 is a schematic view of a ratproof optical cable with a colored outer sheath in embodiment 1;

in fig. 1, 1 is an outer nylon color strip, 2 is a nylon outer sheath, 3 is a stainless steel band, 4 is an optical fiber, 5 is a water-blocking yarn, 6 is a central reinforcement, 7 is a sleeve water-blocking yarn, 8 is a full-dry sleeve, 9 is an open cable, and 10 is an inner PE sheath;

fig. 2 is a schematic view (left) and a projection measurement result (right) of the outer sheath of the ratproof optical cable with the colored outer sheath in example 1;

FIG. 3 is a pictorial view of the ratproof optical cable obtained in example 2;

FIG. 4 is a rat-proof optical cable test qualified sample with a colored-bar composite outer sheath in example 1;

fig. 5 is a real object diagram of the composite outer sheath in the rat-proof optical cable in comparative example 1 and a sample diagram after a torsion experiment;

in FIG. 5, A is a real object diagram of the composite outer sheath prepared in comparative example 1; fig. 5B is a sample diagram after the composite outer sheath prepared in comparative example 1 was subjected to a torsion test.

The same reference numbers will be used throughout the drawings to refer to the same or like elements or structures, wherein: 1 is outer nylon color strip, 2 is nylon oversheath, 3 is stainless steel band, 4 is optic fibre, 5 is the yarn that blocks water, 6 is central reinforcement, 7 is the sleeve pipe yarn that blocks water, 8 is full-dry type sleeve pipe, 9 is the open cable rope, 10 is inlayer PE sheath.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the invention. In addition, the technical features involved in the respective embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Through practical observation and experimental groping, the reason that the color strips of the rat-proof optical cable are easy to fall off after being laid is found to be two: firstly, the color strips and the nylon sheath are layered to cause the color strips to fall off, and the color strips directly fall off; and secondly, the PE sheath and the nylon sheath are layered to cause the nylon sheath to deform, so that the color strips and the nylon sheath are more easily layered, and the color strips are indirectly caused to fall off. The problem that the color strips on the composite outer sheath fall off is solved, the problem is more difficult, and two aspects of layering of the inner sheath and the outer sheath and layering of the color strips and the outer nylon sheath need to be considered.

According to the invention, maleic anhydride is added into the PE material for forming the inner layer PE sheath, the PE material, the nylon material and the nylon material are co-extruded, the nylon material for forming the outer layer nylon sheath and the nylon material for forming the outer layer nylon color strips are co-extruded, the drying material and the extruder temperature in the thermoplastic extrusion process are strictly controlled, the sheath is formed at one step, firm color strips can be formed on the surface of the nylon sheath, the inner layer PE sheath and the outer layer nylon sheath are not easy to separate, and the nylon material for forming the outer layer nylon color strips is a nylon 12 material containing color master in a preset proportion. The nylon color strips obtained by matching the nylon 12 pigment with the nylon 12 color master are firm, so that the high-strength combined color strip sheath can be formed. Particularly, the PE + nylon + color-bar composite outer sheath formed in one step by adopting a single-head three-layer co-extrusion process is smooth in outer surface, has the characteristics of air blowing performance, rat prevention, easiness in identification and the like, can reduce the phenomenon of layering of inner and outer sheaths of the composite outer sheath in one step forming of the optical cable sheath layer in production, and can greatly improve the production efficiency.

The rat-proof optical cable with the color-bar composite outer sheath provided by the invention is provided with the inner-layer PE sheath, the outer-layer nylon sheath and the outer-layer nylon color-bar integrally-formed composite outer sheath which are tightly combined;

the nylon material forming the outer nylon sheath is a black nylon 12 material;

In the production process, maleic anhydride is added into the PE material forming the inner layer PE sheath, the maleic anhydride, the black nylon 12 material and the nylon material forming the outer layer nylon color strips are co-extruded to form the sheath in one step, and the color strips are formed on the surface of the outer layer nylon sheath.

The PE material containing maleic anhydride and the nylon material are adopted for coextrusion, so that the inner layer PE sheath and the outer layer nylon sheath are tightly combined, the bonding strength of the inner layer PE sheath and the outer layer nylon sheath can be obviously improved, the layered color strips are prevented from falling off, and meanwhile, the production efficiency is favorably improved; according to the mass ratio, the ratio of the maleic anhydride to the PE material = 18-20, preferably PE is High Density Polyethylene (HDPE), and HDPE is beneficial to improving the rat-proof performance; HDPE =18 is more preferable, and the inner PE sheath and the outer nylon sheath in the composite outer sheath obtained by adopting the proportion are not layered and have smooth surfaces, so that the air blowing performance is ensured.

The nylon material for forming the outer layer nylon color strips is a nylon 12 pigment mixed with color master batch in a preset proportion, namely a color strip nylon 12 material; the sample color strips prepared by adopting the ratio of the two nylon materials are intact, the torsion is qualified (the wall thickness of the nylon layer is 0.46-0.54 mm, the weight is 250N, the cable sample is 1 meter, the torsion angle is 180 degrees, and the color strips are not cracked after torsion for 40 times) and the other ratios are layered at the color strip positions like the outer nylon 6 material, the color strip nylon 12 material and the outer nylon 12 material.

The preset proportion is that the color master accounts for 3% -4% of the mass of the nylon 12 pigment, wherein the color master is mainly used for blending the color of the color strip and can be selected according to the requirement, the color master with strong ultraviolet resistance is preferred, in addition, the addition amount of the color master needs to be controlled in a proper range, the identification effect cannot be realized mainly because the color of the color master is too light due to too small addition amount, the color is too bright due to too much addition amount, the ultraviolet resistance effect is poor, and the communication effect of the optical cable is easily influenced.

Furthermore, the rat-proof optical cable also comprises a cable core and a stainless steel band; the cable core is preferably a full-dry cable core formed by twisting a non-metal central reinforcement and a full-dry sleeve, and a plurality of optical fibers are arranged in the full-dry sleeve; the nonmetal central reinforcing part and the full-dry type sleeve layer are stranded into the cable core, so that the weight of the cable can be reduced from the material and structure, and the air blowing performance is ensured;

the stainless steel band is provided with a mooring rope, the stainless steel band is wrapped outside the cable core, the interface parts of the stainless steel band and the cable core are mutually overlapped, and the outer layer of the stainless steel band is extruded with the composite outer sheath.

In addition, the invention also provides a preparation method of the ratproof optical cable with the color bar composite outer sheath, which comprises the following steps:

acquiring a cable core to be sheathed;

the nylon material forming the outer nylon sheath is a black nylon 12 material;

the nylon material for forming the outer layer nylon color strips is a nylon 12 material containing color master in a preset proportion.

And co-extruding the PE material containing maleic anhydride, the nylon material forming the outer nylon sheath and the nylon material forming the outer nylon color strips, so that the PE sheath layer and the nylon sheath layer are tightly combined without layering, and the color strips are formed on the surface of the nylon sheath layer, namely the PE + nylon + color strip one-step formed composite outer sheath is extruded on the outermost layer of the cable core, and the rat-proof optical cable with the color strip composite outer sheath is obtained.

The nylon material forming the outer nylon sheath is black nylon 12. Generally, although color master is added to the color bar to obtain different marks, the same matrix material is used for the sheath material and the color bar to improve the bonding capability of the color bar. However, in the nylon sheath material, once the color master is added, the bonding firmness of the nylon material is seriously influenced. Practice shows that the bonding degree of nylon 6 commonly used in optical cable production is sensitive to color master, the bonding capability of the co-extrusion sheath is reduced after the color master is added, and color strips are easy to fall off; the combination of the nylon sheaths and the nylon color bars with different matrixes is more difficult to meet the requirement of the firmness degree of the color bars. And the nylon 12 can form a color strip firmly combined with the sheath after the color master is added, so that the use requirement is met. Namely, the nylon material for forming the outer layer nylon color strip is nylon 12 pigment matched with nylon 12 color master batch.

The PE material containing maleic anhydride comprises, by mass, maleic anhydride and PE material = 18-20; the PE material is preferably high-density polyethylene (HDPE) and is beneficial to improving the rat-proof performance, more preferably maleic anhydride HDPE = 18.

The experimental result shows that when the mass fraction of the maleic anhydride exceeds 20%, the inner layer HDPE and the outer layer are not delaminated, but the surface is rough, and as shown in FIG. 3, the PE material may be unstably shrunk due to excessive maleic anhydride; HDPE =18, the inner HDPE and the outer nylon material do not delaminate and have smooth surfaces, as shown in fig. 4; and when the ratio of maleic anhydride to HDPE =16 is higher than 84, the bonding between the inner HDPE layer and the outer nylon layer is not tight enough as shown in A in FIG. 5, which indicates that the use of maleic anhydride can significantly affect the bonding between the PE layer and the nylon sheath, and finally the bonding firmness of the color bar is affected by affecting the curing shrinkage of the nylon layer, and the twisting test result of the sheath is shown in B in FIG. 5, which indicates that the addition amount of maleic anhydride needs to be controlled in a proper range, and the addition amount is improper and the color bar is easy to delaminate.

However, the addition of maleic anhydride also brings difficulty to the process. The PE material that contains maleic anhydride, relative ordinary PE material, when crowded altogether with the nylon 12 who extrudes the higher operating temperature, receive the influence of nylon temperature, produce more easily and pile up, solidify and block up the extruder head, even not block up the extruder head, also can lead to the sheath shrink uncontrollable because of partial solidification, influence the adhesion firmness degree of colored steel. Repeated practice shows that the PE material of maleic anhydride and nylon 12 are in good flowing state and have equivalent real-time curing shrinkage degree by accurately controlling the extrusion working temperature and the temperature of each stage of the extruding machine, so that the PE layer and the nylon layer can be well combined.

Further, the three-layer co-extrusion process adopts a single machine head to connect 3 plastic extruders to form a sheath in one step, and specifically comprises the following steps:

(1) The main machine is a single-thread BM screw extruder with a temperature zone of 9 ℃ and is used for adding a PE material containing maleic anhydride and forming an inner layer PE sheath, and the drying temperature is 70 ℃; the 9 temperature zones comprise 5 temperature zones of a machine chamber and 4 temperature zones of a machine head, and the processing temperatures of the machine cavity temperature zone of the temperature control interface of the extruding machine are sequentially set from left to right as follows: 160/180/190/200/210 (unit: ℃, the processing temperature of the machine head temperature zone is 220/230/230/230 (unit: ℃) from left to right in sequence;

wherein, the mass ratio of the maleic anhydride to PE = 18-20, preferably, the PE is high density polyethylene, and more preferably, the maleic anhydride to HDPE = 18;

(2) The color bar fixing machine is a single-thread BM screw extruder with a temperature zone of 9 and is used for adding black nylon 12 forming an outer nylon sheath, wherein the black nylon 12 is prepared by nylon 12 black master and nylon 12 pigment according to a preset proportion and is uniformly mixed; the material drying temperature is 100 ℃, the 9 temperature zones comprise 5 temperature zones of a machine chamber and 4 temperature zones of a machine head, and the processing temperatures are sequentially set in the machine cavity temperature zone of the temperature control interface of the extruding machine from left to right as follows: 205/225/225/230/230 (unit: ℃, the processing temperature of the machine head temperature zone is 225/225/220/220 (unit: ℃) from left to right in sequence; in addition, a movable auxiliary material drying machine is adopted to assist in drying the materials, the drying temperature is 100 ℃, so that the nylon material is preheated, and meanwhile, the damp-proof effect is achieved.

(3) The movable color bar machine is a single-thread BM screw extruder with a temperature zone of 5 ℃, and is used for adding a nylon material for forming outer nylon color bars, wherein the nylon material for forming the outer nylon color bars is prepared from nylon 12 color master and nylon 12 pigment according to a preset proportion, the color master is uniformly mixed, and the color master in the color bars is selected to have a proper color according to the requirement; the preset proportion is that the nylon 12 color master accounts for 3 to 4 percent of the mass of the nylon 12 pigment;

the 5 temperature zones comprise 3 temperature zones of a machine chamber and 2 temperature zones of a machine head, and the machine cavity temperature zone of a temperature control interface of the extruding machine is sequentially set to be 190/200/225 ℃ at the processing temperature from left to right; the processing temperature of 225/225℃ and the drying temperature of 70 ℃ are set in the head temperature zone from left to right;

the color strip nylon extruding machine uses a special nylon screw, and the screws are numbered: sm-22201 JH 22070401-03. The nylon material forming the outer nylon color strips is less in consumption and high in viscosity, so that the screw rod is easy to wind to cause screw rod pause to cause color breaking, and the screw rod special for nylon can increase the thrust of the screw rod, so that the material is not easy to accumulate in the screw rod, and the screw rod is prevented from pausing and color breaking.

The experimental result shows that the outer layer nylon 6 material mixed with the color strip nylon 6 material, the outer layer nylon 6 material mixed with the color strip nylon 12 material and the outer layer nylon 12 material mixed with the color strip nylon 6 material have layering phenomena at the color strip position, and the color strip of the sample prepared by mixing the outer layer nylon 12 material mixed with the color strip nylon 12 material is intact and qualified after torsion.

The results of the torsion experiments show that the nylon 12 material of the outer layer is matched with the sample of the color strip nylon 12 material, the wall thickness of the nylon layer is 0.46 mm-0.54 mm, the weight of the nylon layer is 250N, the sample of the 1 meter cable is twisted for 180 degrees, and the color strip is not cracked after being twisted for 40 times, as shown in figure 4.

And co-extruding the PE material forming the inner PE sheath, the nylon material forming the outer nylon sheath and the nylon material forming the outer nylon color strips by adopting a three-layer co-extrusion process, and extruding the composite outer sheath of the PE, the nylon and the color strips which is formed in one step on the outermost layer of the cable core part to obtain the ratproof optical cable with the color strip composite outer sheath.

Preferably, the high-density polyethylene (HDPE) containing maleic anhydride is co-extruded with the nylon material and is formed at one time by a single machine. In the invention, a single machine head is connected with 3 plastic extruders for one-step molding, so that the production efficiency can be improved, the diameter of the optical cable can be reduced, and the problem of high defective rate in the production of single-layer nylon materials can be effectively solved.

Further, the cable core to be sheathed is obtained according to the following steps:

twisting the central reinforcing piece and the full-dry type sleeve into a full-dry type cable core, wherein a plurality of optical fibers are arranged in the full-dry type sleeve;

the stainless steel belt is longitudinally wrapped outside the full-dry cable core, and the interface parts of the stainless steel belt are mutually overlapped;

and adding 2 twisted aramid fiber open mooring ropes into the stainless steel belt at 180 degrees to obtain the cable core to be sheathed.

The central reinforcing part is preferably a non-metal central reinforcing part, and the non-metal central reinforcing part and the full-dry type sleeve layer are twisted into a cable core, so that the weight of the cable can be reduced in material and structure, and the air blowing performance is ensured.

The following are examples:

embodiment 1 rat-proof optical cable with color-bar composite outer sheath

The rat-proof optical cable with the color bar composite outer sheath is shown in figure 1 and comprises a cable core, a stainless steel belt, a cable opening rope and a composite outer sheath; a plurality of optical fibers are arranged in the cable core, a stainless steel band is wound outside the cable core, the interface parts of the stainless steel band are mutually overlapped, and a composite outer sheath is extruded on the outer layer of the stainless steel band; the composite outer sheath is a PE (polyethylene), nylon and color strip one-step forming sheath, the inner layer of the composite outer sheath is a PE sheath, the outer layer of the composite outer sheath is a nylon sheath, and the color strips are arranged on the surface of the nylon sheath;

the rat-proof optical cable with the color bar composite outer sheath is specifically obtained according to the following preparation method:

the central reinforcer and the full-dry type sleeve are twisted into a full-dry type cable core, and a plurality of optical fibers are arranged in the full-dry type sleeve;

longitudinally wrapping stainless steel bands outside the obtained layer-stranded cable core, overlapping the interface parts together, and adding 2 twisted aramid fiber open cables at 180 degrees;

using extrusion molding dies such as a single machine head, a full-color spreader cone and a color bar die cover, and adopting a three-layer co-extrusion process to form the sheath at one time to obtain the ratproof optical cable with the color bar composite outer sheath;

the three-layer co-extrusion process comprises the following specific steps:

(1) The main machine is a single-thread BM screw extruder with a 9-temperature zone, which is used for adding a PE material containing maleic anhydride and forming an inner layer PE sheath, the drying temperature is 70 ℃, the 9-temperature zone comprises 5 temperature zones of a machine chamber and 4 temperature zones of a machine head, and the machine cavity temperature zone of a temperature control interface of the extruder is sequentially provided with the processing temperatures from left to right as follows: 160/180/190/200/210 (unit: ℃, the processing temperature of the machine head temperature zone is set from left to right as follows: 220/230/230/230 (unit:. Degree. C.);

wherein PE is high density polyethylene, maleic anhydride HDPE = 18;

(2) The color bar fixing machine is a single-thread BM screw extruder with a temperature zone of 9 and is used for adding black nylon 12 for forming an outer nylon sheath, wherein the black nylon 12 is prepared according to the condition that nylon 12 black master accounts for 3% of the mass of nylon 12 pigment, and black nylon 12 is obtained by uniformly mixing materials; the 9 temperature zones comprise 5 temperature zones of a machine chamber and 4 temperature zones of a machine head, and the processing temperatures of the machine cavity temperature zone of the temperature control interface of the extruding machine are sequentially set from left to right as follows: 205/225/225/230/230 (unit: ℃, processing temperature of 225/225/220/220 (unit: ℃ C.) is set in the machine head temperature zone from left to right in sequence, and material drying temperature is 100 ℃; and a movable auxiliary material drier is additionally arranged for auxiliary material drying, the auxiliary material drier is provided with a material pumping device, nylon materials are pumped into a hopper of a plastic extruding machine after being pumped into the hopper for drying for 2 hours, and the auxiliary material drying temperature is 100 ℃.

(3) Remove the colored strip machine and be the single thread BM screw rod extruding machine in 5 warm areas for add the nylon material that forms outer nylon colored strip: the nylon material for forming the outer layer nylon color strips is prepared according to the condition that the blue master batch of nylon 12 accounts for 3 percent of the mass of the nylon 12 pigment, and the blue nylon material is obtained by uniformly mixing;

the 5 temperature zones comprise 3 temperature zones of a machine chamber and 2 temperature zones of a machine head, and the processing temperature of the machine cavity temperature zone of the temperature control interface of the extruding machine is set to be 190/200/225℃ from left to right; the processing temperature of 225/225℃ and the drying temperature of 70 ℃ are set in the head temperature zone from left to right;

the color strip nylon extruding machine uses a special nylon screw, and the screws are numbered: sm-22201 JH 22070401-03;

adding color strips on the surface of the sheath; the full-color tap with 2 through holes (GQ L = 107.8Z-AC-1.5-3/9-2 TH-11.0 x 2), two through holes are arranged at the 3/9 position, and the left and right through holes respectively correspond to the 3-point and 9-point directions during installation.

The end face of the die cover is flush with the end face of the large platform of the current divider; from left to right direction production line: the color bar feeding port of the mold cover is aligned with the through hole of 9 points of the splitter; production line from right to left: a feeding port of the color bar of the mold cover is aligned with a through hole at the 3 point of the splitter; 2 layers of 60 filter screens are used at the filter screens of the 2 color bar machines;

before starting up, firstly starting a fixed color bar machine, and firstly discharging a nylon material and then discharging an HDPE material; when a sample is debugged, the fixed color bar machine is closed, the diameter of the inner layer is measured, then the fixed color bar machine is opened, the total diameter is measured, the thickness of the nylon layer is obtained by subtracting the two diameters, as shown in figure 2 (left), and the accurate thickness of the nylon layer is measured by using an instrument projection after being sliced, as shown in figure 2 (right).

Example 2 ratproof optical cable with color-stripe composite outer sheath

The rat-proof optical cable is prepared by the following preparation method in the same way as the embodiment 1:

the rat-proof optical cable obtained in the same manner as in example 1 except that the host machine used HDPE containing maleic anhydride, HDPE =20, is shown in fig. 3.

As can be seen from fig. 3, HDPE =20, the inner HDPE layer does not delaminate from the outer nylon layer.

Example 3 color strip firmness test of ratproof optical cable with color strip outer sheath

Torsion tests are carried out on the ratproof optical cable with the color-strip composite outer sheath obtained in the embodiment 1, and results show that the nylon sheath on the outer layer is made of nylon 12 material and blended with the color-strip nylon 12 material, the wall thickness of the nylon layer is 0.46 mm-0.54mm, 250N weight is added, a 1-meter cable sample is twisted at an angle of 180 degrees, and color strips are not cracked after being twisted for 40 times, as shown in FIG. 4.

Comparative example 1 rat-proof optical cable

the rat-proof optical cable obtained in the same way as in example 1 except that HDPE containing maleic anhydride, HDPE: 16.

As can be seen from fig. 5A, when HDPE =16, the inner HDPE layer is not tightly bonded to the outer nylon layer, and a significant gap is observed; the torsion experiment result of the sheath in fig. 5B shows that the sheath is easy to delaminate, easily causes the color strips to fall off, and cannot play a role in identification when the optical cable needs to be maintained.

Comparative example 2 rat-proof optical cable

The rat-proof optical cable is prepared by the following preparation method in the same way as the example 1:

except that the nylon material forming the outer nylon color strips is nylon 6 material and the color strips are nylon 6 material, the ratproof optical cable obtained in the same way as the embodiment 1 has a layering phenomenon at the color strips.

Comparative example 3 rat-proof optical cable

except that the nylon material forming the outer nylon color strips is nylon 6 material and blended with color strip nylon 12 material, the ratproof optical cable obtained in the same way as the embodiment 1 has a layering phenomenon at the color strips.

Comparative example 4 rat-proof optical cable

except that the nylon material forming the outer nylon color strips is nylon 12 material and color strip nylon 6 material, the ratproof optical cable obtained in the same way as the embodiment 1 has a layering phenomenon at the color strips.

It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A ratproof optical cable with a color bar composite outer sheath is characterized by comprising an inner layer PE sheath, an outer layer nylon sheath and an outer layer nylon color bar composite outer sheath which are tightly combined;

the nylon material forming the outer nylon sheath is a black nylon 12 material;

2. The ratproof optical cable with a colorstripe composite outer jacket of claim 1, wherein maleic anhydride HDPE = 18.

3. The ratproof optical cable with a color-strip composite outer sheath according to claim 1 or 2, wherein the PE material is high-density polyethylene.

4. The ratproof optical cable with color-strip composite outer sheath according to claim 1, wherein the color master in the nylon material forming the outer nylon color strip accounts for 3-4% of the mass of the nylon 12 pigment.

5. The ratproof optical cable with color-striped composite outer sheath according to claim 4, wherein the nylon material forming the outer nylon color stripes comprises 3% of color masterbatch by mass of 12 nylon pigments.

6. The ratproof optical cable with color-stripped composite outer sheath according to claim 1, further comprising a cable core; the cable core comprises a layer-twisted cable core and a stainless steel belt; the layer-twisted cable core is twisted into a full-dry cable core by a non-metal central reinforcer and a full-dry sleeve, and a plurality of optical fibers are arranged in the full-dry sleeve; the outer layer of the layer-stranded cable core is longitudinally wrapped with a stainless steel band, and the stainless steel band is provided with an open mooring rope.

7. The preparation method of the ratproof optical cable with the color bar composite outer sheath as claimed in any one of claims 1 to 6, characterized by comprising the following steps:

acquiring a cable core to be sheathed;

the nylon material forming the outer nylon sheath is a black nylon 12 material;

8. The method for preparing the ratproof optical cable with the color bar composite outer sheath as claimed in claim 7, wherein the three-layer co-extrusion process adopts a single-head connection 3 extruders to form the sheath in one step, and comprises the following steps:

(1) The host machine adds the PE material forming the inner layer PE sheath, the material drying temperature is 70 ℃, the host machine temperature zone comprises 5 temperature zones of the machine chamber and 4 temperature zones of the machine head, and the processing temperatures are sequentially set in the machine cavity temperature zone of the temperature control interface of the extruding machine from left to right as follows: 160/180/190/200/210, DEG C, and the processing temperature of the machine head temperature zone is set as follows from left to right: 220/230/230/230, deg.C;

(3) Adding a nylon material for forming the outer-layer nylon color strips into the movable color strip machine, wherein the material drying temperature is 70 ℃, the temperature zone of the movable color strip machine comprises 3 temperature zones of a machine chamber and 2 temperature zones of a machine head, and the processing temperature is 190/200/225 ℃ from left to right in the machine cavity temperature zone of the temperature control interface of the extruding machine; the processing temperature of 225/225℃ and the drying temperature of 70 ℃ are set in the head temperature zone from left to right; and a special nylon screw is used, and the number of the screw is as follows: sm-22201JH 220704-03.

9. The method for preparing the ratproof optical cable with the color bar composite outer sheath as claimed in claim 7, wherein the PE material forming the inner PE sheath is HDPE containing maleic anhydride, and the preferred mass ratio is as follows: maleic anhydride HDPE = 18.

10. The preparation method of the ratproof optical cable with the color strip composite outer sheath as claimed in claim 7, wherein the nylon material forming the outer nylon color strip is prepared from the following raw materials in parts by mass, wherein the raw materials comprise 3-4 parts of color master batch, 12 parts of nylon pigment.