CN115312272A - Silicone rubber insulation medium-voltage mining flexible cable and manufacturing method thereof - Google Patents

Abstract

The invention belongs to the technical field of flexible cables, and discloses a silicone rubber insulation medium-voltage mining flexible cable and a manufacturing method thereof. This mining flexible cable of silicon rubber insulation middling pressure includes the sheath, the cable core with around the package shielding layer, the outside of cable core is located to the sheath cover, the cable core includes the many tangent interior heart yearns that set up, interior heart yearn includes the conductor, the silicon rubber insulating layer and the weaving shielding layer that the silicon rubber insulating layer outside was located to the cover outside the conductor are located to the cover, interior heart yearn still includes first package shielding layer and second around the package shielding layer, first package shielding layer is located between conductor and the silicon rubber insulating layer, the second is located the silicon rubber insulating layer and is woven between the shielding layer around the package shielding layer. The invention provides a silicon rubber insulation medium-voltage mining flexible cable which is characterized in that a first wrapping shielding layer is firstly prepared outside a conductor, then a silicon rubber insulation layer is extruded outside the first wrapping shielding layer, finally a second wrapping shielding layer is prepared outside the silicon rubber insulation layer, and the single-layer extrusion of the silicon rubber insulation layer can be completed by adopting traditional hot baking channel equipment.

Description

Silicone rubber insulation medium-voltage mining flexible cable and manufacturing method thereof

Technical Field

The invention relates to the technical field of flexible cables, in particular to a silicone rubber insulation medium-voltage mining flexible cable and a manufacturing method thereof.

Background

The general structure of the medium-voltage mining flexible cable comprises a semiconductive inner shielding layer, an ethylene-propylene medium-voltage insulating layer and a semiconductive insulating shielding layer, the cable is usually prepared by adopting a three-layer co-extrusion process, and the extrusion process of the cable is completed by adopting imported three-layer co-extrusion sulfur-connecting extrusion equipment. The working environment of the coal mine is narrow, the environment temperature is high, and the cable needs to move ceaselessly when in use. The silicon rubber insulating layer has better flexibility and can resist high and low temperatures, so the ethylene propylene medium-voltage insulating layer is mainly made of the silicon rubber insulating layer.

The extrusion mode of the silicon rubber insulating layer comprises steam sulfur-connecting pipeline extrusion and hot air pipeline extrusion, and for the low-voltage silicon rubber cable, the extrusion efficiency of the hot air pipeline is higher than that of the steam sulfur-connecting pipeline, so the low-voltage silicon rubber cable is mainly extruded by the hot air pipeline; the medium-voltage silicon rubber cable comprises a semiconductive conductor shielding layer taking silicon rubber as a base material, a silicon rubber insulating layer and a semiconductive insulating shielding layer taking silicon rubber as a base material, three layers are extruded simultaneously during preparation, and a hot air pipeline is usually a single machine head and cannot be extruded for three layers at one time.

In the prior art, the hot drying channel equipment is generally transformed into a three-layer co-extrusion machine head, so that the medium-voltage silicone rubber cable can be extruded and prepared at one time, the production efficiency is low, and in the extrusion process, gaps or bulges are easy to occur between three layers of materials, the quality of the cable is seriously reduced, and the performance of the cable is influenced.

Disclosure of Invention

The invention aims to provide a silicon rubber insulation medium-voltage mining flexible cable and a manufacturing method thereof, and aims to improve the production efficiency and the production quality of the flexible cable.

In order to achieve the purpose, the invention adopts the following technical scheme:

the mining flexible cable of silicon rubber insulation middling pressure includes:

a sheath;

the cable core, the sheath cover is located the outside of cable core, the cable core includes the many tangent interior heart yearns that set up, interior heart yearn includes that conductor, cover are located the silicon rubber insulating layer and the cover in the conductor outside are located the woven shield in the silicon rubber insulating layer outside, interior heart yearn still includes around the package shielding layer, include first around the package shielding layer and the second around the package shielding layer, first locate around the package shielding layer the conductor with between the silicon rubber insulating layer, the second is located around the package shielding layer the silicon rubber insulating layer with weave between the shielding layer.

Optionally, the cable core further includes a plurality of filling members, each of the filling members is tangent to two adjacent inner core wires, and each of the filling members is tangent to the sheath.

Optionally, a central reinforcing wire is provided within the filler element.

Optionally, the outer side of the sheath is sleeved with a wear-resistant layer.

Optionally, the silicone rubber insulated medium-voltage mining flexible cable further comprises a coating layer, and the coating layer is sleeved on the outer side of the wear-resistant layer.

Optionally, the first wrapped shielding layer and the second wrapped shielding layer are wrapped semi-conductive nylon layers.

Optionally, the first lapping shielding layer and the second lapping shielding layer are both 0.01mm-0.05mm thick.

Optionally, the thicknesses of the first lapping shielding layer and the second lapping shielding layer are both 0.03mm.

Optionally, the silicone rubber insulated medium-voltage mining flexible cable further comprises a wrapping belt, the wrapping belt is sleeved on the outer side of the cable core, and the sheath is sleeved on the outer side of the wrapping belt.

The manufacturing method of the silicone rubber insulation medium-voltage mining flexible cable is based on any scheme, and is characterized by comprising the following steps:

providing one of the conductors;

the first lapping shielding layer is formed by lapping and covering the conductor in the left direction;

extruding and preparing the silicon rubber insulating layer outside the first wrapping shielding layer;

and the silicone rubber insulating layer is externally overlapped and lapped in the left direction to form the second lapping shielding layer.

The invention has the beneficial effects that: according to the silicon rubber insulation medium-voltage mining flexible cable provided by the invention, the first wrapping shielding layer is arranged between the conductor and the silicon rubber insulation layer, the second wrapping shielding layer is arranged between the silicon rubber insulation layer and the braided shielding layer, when the flexible cable is prepared, the first wrapping shielding layer is prepared outside the conductor, then the silicon rubber insulation layer is extruded outside the first wrapping shielding layer, and finally the second wrapping shielding layer is prepared outside the silicon rubber insulation layer.

The manufacturing method of the silicone rubber insulated medium-voltage mining flexible cable comprises the steps of forming a first wrapping shielding layer by overlapping and wrapping the conductor in the left direction, extruding and preparing a silicone rubber insulating layer outside the first wrapping shielding layer, and forming a second wrapping shielding layer by overlapping and wrapping the silicone rubber insulating layer in the left direction, so that the preparation process of the flexible cable is optimized, the production efficiency is improved, and the production quality of the flexible cable is improved.

Drawings

Fig. 1 is a schematic structural diagram of a silicone rubber insulated medium-voltage mining flexible cable provided by an embodiment of the invention.

In the figure:

1. a sheath;

211. a conductor; 212. a silicon rubber insulating layer; 213. weaving a shielding layer; 2141. a first lapping shielding layer; 2142. a second lapping shielding layer;

22. a filling member;

3. wrapping belts;

4. and a wear-resistant layer.

Detailed Description

The present invention will be described in further detail with reference to the drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

In the description of the present invention, unless otherwise explicitly specified or limited, the terms "connected," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integral to one another; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or may be connected through the use of two elements or the interaction of two elements. The specific meanings of the above terms in the present invention can be understood in a specific case to those of ordinary skill in the art.

In the present invention, unless expressly stated or limited otherwise, the recitation of a first feature "on" or "under" a second feature may include the recitation of the first and second features being in direct contact, and may also include the recitation that the first and second features are not in direct contact, but are in contact via another feature between them. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the description of the present embodiment, the terms "upper", "lower", "right", etc. are used in an orientation or positional relationship based on that shown in the drawings only for convenience of description and simplicity of operation, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used only for descriptive purposes and are not intended to be limiting.

As shown in fig. 1, the present embodiment provides a silicone rubber insulated medium voltage mining flexible cable. This mining flexible cable of silicon rubber insulation middling pressure includes sheath 1, the cable core with around the package shielding layer, the outside of cable core is located to 1 cover of sheath, the cable core includes the interior heart yearn of many tangent settings, interior heart yearn includes conductor 211, the silicon rubber insulating layer 212 and the weaving shielding layer 213 of cover locating the silicon rubber insulating layer 212 outside in the conductor 211 outside are located to the cover, interior heart yearn still includes around the package shielding layer, include first around package shielding layer 2141 and second around package shielding layer 2142 around the package shielding layer, first locate between conductor 211 and the silicon rubber insulating layer 212 around package shielding layer 2141, the second is located between silicon rubber insulating layer 212 and the weaving shielding layer 213 around package shielding layer 2142.

According to the silicone rubber insulation medium-voltage mining flexible cable provided by the invention, the first wrapping shielding layer 2141 is arranged between the conductor 211 and the silicone rubber insulation layer 212, the second wrapping shielding layer 2142 is arranged between the silicone rubber insulation layer 212 and the woven shielding layer 213, when the flexible cable is prepared, the first wrapping shielding layer 2141 is prepared outside the conductor 211, the silicone rubber insulation layer 212 is extruded outside the first wrapping shielding layer 2141, and the second wrapping shielding layer 2142 is prepared outside the silicone rubber insulation layer 212.

In the present embodiment, the conductor 211 may be made of category 5 or category 6 stranded bare copper or tin-plated copper. The copper has high conductivity and low cost. The conductor 211 is made from an original copper rod through the processes of wire drawing, deplating, bunching, compound stranding and the like.

Optionally, the first wrapped shielding layer 2141 and the second wrapped shielding layer 2142 are both wrapped semi-conductive nylon layers. The surface of the existing semi-conductive cotton cloth layer is rough, the extrusion surface is easy to have the defects of bulge or unevenness and the like, and the volume resistance of the lapping semi-conductive nylon layer is less than or equal to 4 multiplied by 10 ⁴ Omega cm, the left-hand lapping is adopted for preparation, the overlapping rate is 20-25%, and the defects are few.

Optionally, the thicknesses of the first and second wrapped shielding layers 2141 and 2142 are both 0.01mm to 0.05mm. The thickness of the existing semiconductive cotton cloth layer is generally larger than 0.1mm, defects are easily generated in the extrusion preparation process, the thicknesses of the first wrapping shielding layer 2141 and the second wrapping shielding layer 2142 in the embodiment are both 0.01mm-0.05mm, the thicknesses are small, and the defects are not easily generated in the preparation process. Preferably, the thicknesses of the first and second wrapped shielding layers 2141 and 2142 are both 0.03mm.

In this embodiment, the cable core further includes a plurality of filling members 22, each filling member 22 is tangent to two adjacent inner core wires, and each filling member 22 is tangent to the sheath 1, and the filling members 22 can fill up a gap between the inner core wire and the sheath 1, so as to increase the tensile strength of the flexible cable. Specifically, the filler 22 is extruded from silicone rubber, which has a high temperature resistance level and can also increase the flexibility of the cable.

Further, a central reinforcing wire is provided in the filling member 22 to enhance the strength of the filling member 22. Illustratively, the central reinforcing yarn may be a tear yarn or a polyester yarn. When the filling member 22 is prepared, silicone rubber is extruded outside the central reinforcing wire, and the diameter of the filling member 22 can be adjusted as required. Illustratively, the extrusion temperature of the silicone rubber may be set to 450 ℃, 300 ℃ and 300 ℃ in this order from the die.

Optionally, the material of the silicone rubber insulating layer 212 is platinum vulcanized silicone rubber, which has high purity and cleanliness and can effectively prevent color paste, color masterbatch and the like from being mixed in to reduce the electrical performance of the flexible cable. Specifically, the formula of the silicone rubber is as follows: 0.6% of platinum vulcanizing agent A, 1% of agent B and 0.2% of heat-resistant agent.

The silicone rubber insulation layer 212 is prepared by an extrusion process, and the prepared silicone rubber is mixed in an open mill, rolled for about 28 times and then sliced for extrusion. During extrusion, in order to ensure that the concentricity during extrusion is more than or equal to 92 percent, a vertical hot drying channel extruder is adopted to extrude the silicon rubber insulating layer 212, and the extrusion temperature is set to be 450 ℃, 300 ℃ and 300 ℃ from the head to the back in sequence.

In this embodiment, the braided shield layer 213 is a mixed braided shield layer 213 of tinned copper wire and fiber. The weaving density of the tinned copper wires and the weaving density of the fibers are both greater than 80%, the overall weaving density is greater than or equal to 96%, the tinned copper wires play a shielding role, and meanwhile, the galvanized copper wires of the inner core wires can be combined together to be used as a ground wire for grounding; the woven fabric is woven by fibers with different colors, such as red, blue or white, and the like, and is used for distinguishing the phase lines.

Optionally, the silicone rubber insulated medium-voltage mining flexible cable further comprises a wrapping belt 3, the wrapping belt 3 is sleeved on the outer side of the cable core, and the sheath 1 is sleeved on the outer side of the wrapping belt 3. During processing, after the cable core is twisted in the right direction, a layer of wrapping tape 3 is prepared in the outer side of the cable core in the left direction in a wrapping mode, the wrapping tape 3 is a non-hygroscopic wrapping tape 3, so that the longitudinal water blocking effect is achieved, and the conductor 211 is prevented from being oxidized or the electrical performance of the conductor 211 is prevented from being affected. Illustratively, the material of the bag strap 3 is non-woven fabric, the thickness is 0.05mm-0.15mm, the overlapping rate of the bag strap 3 is 20% -25%, wherein the thickness of the bag strap 3 is preferably 0.1mm.

Optionally, the sheath 1 is made of a highly tear-resistant silicone rubber sheath 1 to improve the reliability of the use of the sheath 1. Optionally, the formula of the silicone rubber is a double-two-four vulcanizing agent formula, so that the defects of overlarge outer diameter, nonuniform vulcanization and air holes of the sheath 1 are avoided. The formula specifically comprises: 1.5 percent of bis-tetra-vulcanizing agent, 0.4 percent of defrosting agent and 1 percent of red paste. The prepared silicone rubber is mixed in an open mill, rolled for 28 times and then sliced for extrusion. During preparation, a vertical hot baking channel extruder is adopted for extrusion, and the extrusion temperature is sequentially set to 480 ℃, 400 ℃, 350 ℃ and 300 ℃ from a machine head.

The flexible cable needs to be moved frequently when in use, so that the service life of the flexible cable is prolonged. The outer side of the sheath 1 is sleeved with a wear-resistant layer 4.

Specifically, the wear-resistant layer 4 is a fiber woven layer, and the fiber woven layer is made of polyester yarns with high tearing resistance. In the prior art, the fiber braided layer is made of glass fiber or aramid fiber, so that the glass fiber has poor wear resistance and is easy to damage; aramid fiber has good wear resistance but is expensive. The high-tear-resistance polyester yarn has excellent wear resistance and low price.

Further, the silicon rubber insulation medium voltage mining flexible cable further comprises a coating layer, and the coating layer is sleeved on the outer side of the wear-resistant layer 4. The coating layer is silica gel resin which can resist the temperature of 200 ℃, the clearance of the fiber braided layer can be filled, the adhesive force between the fiber braided layer and the sheath 1 can also be increased, and the color of the coating layer can be set as required.

The embodiment of the invention also provides a manufacturing method of the silicone rubber insulation medium-voltage mining flexible cable, which is based on the silicone rubber insulation medium-voltage mining flexible cable and comprises the following steps:

s1, providing a conductor 211;

s2, lapping and forming a first lapping shielding layer 2141 in a left-hand overlapping mode outside the conductor 211;

s3, preparing a silicon rubber insulating layer 212 by extruding outside the first wrapping shielding layer 2141;

for example, in a flexible cable with a cross-sectional area of 70 mm square and a thickness of the silicon rubber insulating layer 212 of 5.5mm, when the silicon rubber insulating layer 212 is extruded, the conductor 211 needs to be preheated, where the preheating temperature may be 100 ℃, so as to increase the adhesion between the first wrapped shielding layer 2141 and the silicon rubber insulating layer 212, and then the vulcanization speed can be increased. The extrusion speed during extrusion can be set to 10m/min, and cooling treatment is carried out after extrusion.

And S4, lapping and forming a second lapping shielding layer 2142 in a left-hand overlapping mode outside the silicon rubber insulating layer 212.

The manufacturing method of the silicone rubber insulation medium-voltage mining flexible cable comprises the steps of forming a first wrapping shielding layer 2141 by overlapping and wrapping the conductor 211 in the left direction, preparing a silicone rubber insulation layer 212 by extruding the first wrapping shielding layer 2141, and forming a second wrapping shielding layer 2142 by overlapping and wrapping the silicone rubber insulation layer 212 in the left direction, so that the preparation process of the flexible cable is optimized, the production efficiency is improved, and the production quality of the flexible cable is improved.

Taking a flexible cable with a sectional area of 70 square millimeters as an example, a traditional three-layer extrusion process is adopted, the extrusion speed of three-layer extrusion is about 5m/min, while the single-layer extrusion speed of the flexible cable provided by the embodiment can reach 10m/min, and the extrusion efficiency is improved to 2 times of the original extrusion speed. The flexible cable provided by the embodiment can meet the power frequency withstand voltage test of 2.5U0+2kV, and the wear resistance of the cable is effectively improved.

It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Numerous obvious variations, adaptations and substitutions will occur to those skilled in the art without departing from the scope of the invention. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.

Claims (10)

1. Mining flexible cable of silicon rubber insulation middling pressure, its characterized in that includes:

a sheath (1);

the cable core, sheath (1) cover is located the outside of cable core, the cable core includes the interior heart yearn of many tangent settings, the interior heart yearn includes conductor (211), cover and locates silicon rubber insulating layer (212) and the cover in the conductor (211) outside are located the braided shielding layer (213) in silicon rubber insulating layer (212) outside, the interior heart yearn still includes around the package shielding layer, include first around package shielding layer (2141) and second around package shielding layer (2142) around the package shielding layer, first locate around package shielding layer (2141) conductor (211) with between silicon rubber insulating layer (212), the second is located around package shielding layer (2142) silicon rubber insulating layer (212) with weave between the shielding layer (213).

2. The silicone rubber insulated medium voltage mining flexible cable according to claim 1, characterized in that the cable core further comprises a plurality of fillers (22), each of the fillers (22) being tangent to two adjacent inner core wires, and each of the fillers (22) being tangent to the sheath (1).

3. The silicone rubber insulated medium voltage mining flexible cable according to claim 2, characterized in that a central reinforcing wire is provided inside the filler piece (22).

4. The silicone rubber insulated medium voltage mining flexible cable according to claim 1, characterized in that the outer side of the sheath (1) is sheathed with a wear layer (4).

5. The silicone rubber-insulated medium-voltage mining flexible cable according to claim 4, characterized in that it further comprises a coating layer which is sleeved on the outside of the wear-resistant layer (4).

6. The silicone rubber-insulated medium-voltage mining flexible cable according to claim 1, wherein the first and second wrapped shielding layers (2141, 2142) are both wrapped semiconductive nylon layers.

7. The silicone rubber-insulated medium-voltage mining flexible cable according to claim 6, characterized in that the first and second wrapped shielding layers (2141, 2142) each have a thickness of 0.01mm to 0.05mm.

8. The silicone rubber-insulated medium-voltage mining flexible cable according to claim 7, characterized in that the first and second wrapped shielding layers (2141, 2142) each have a thickness of 0.03mm.

9. The silicone rubber insulation medium voltage mining flexible cable according to claim 1, further comprising a wrapping tape (3), wherein the wrapping tape (3) is sleeved on the outer side of the cable core, and the sheath (1) is sleeved on the outer side of the wrapping tape (3).

10. The manufacturing method of the silicone rubber insulated medium voltage mining flexible cable is based on the silicone rubber insulated medium voltage mining flexible cable according to any one of claims 1 to 9, and is characterized by comprising the following steps:

-providing a said conductor (211);

the first lapping shielding layer (2141) is formed by lapping and covering the conductor (211) in the left direction;

extruding and preparing the silicon rubber insulating layer (212) outside the first wrapping shielding layer (2141);

and the second lapping shielding layer (2142) is formed by lapping and lapping the silicon rubber insulating layer (212) in the left direction.

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