CN114649110A

CN114649110A - Preparation method of insulated cable with fireproof function

Info

Publication number: CN114649110A
Application number: CN202210323448.1A
Authority: CN
Inventors: 胡乐云; 罗锡群; 朱敬轩; 周慧玲
Original assignee: Wenzhou Weiying New Material Cable Co ltd
Current assignee: Wenzhou Weiying New Material Cable Co ltd
Priority date: 2022-03-30
Filing date: 2022-03-30
Publication date: 2022-06-21

Abstract

The invention relates to the technical field of cables, and discloses a preparation method of an insulated cable with a fireproof function, which comprises the following steps: step a: carrying out down-leading continuous casting on the copper alloy after the smelting is finished; step b: drawing the homogenized copper alloy rod to a preset copper alloy wire diameter AD through a continuous drawing and continuous annealing multi-channel wire drawing machine; step c: preparing a conductive core with the diameter of D and the resistivity of P by twisting and untwisting a copper alloy wire; step d: extruding the inner insulating material and the conductive core in a single-screw extruder to form a first cable; step e: the fireproof layer and the outer insulating layer are processed and formed by adopting a plastic extruding machine; step f: c, forming the fireproof layer and the outer insulating layer obtained in the step d through chemical crosslinking to obtain the insulating cable with the fireproof function; the invention adopts double-layer insulation, greatly improves the insulation performance of the cable, and is also provided with another fireproof layer, thereby greatly improving the safety performance of the cable.

Description

Preparation method of insulated cable with fireproof function

Technical Field

The invention relates to the technical field of cables, in particular to a preparation method of an insulated cable with a fireproof function.

Background

The cable is made of one or more mutually insulated conductors and an outer insulation protective layer, and is a wire for transmitting electric power or information from one place to another place.

Under the trend of national urbanization development and vertical urban building development in the world, the demands of people on the security of fire, personal safety, building safety and property safety are increasing day by day.

Mineral insulated cables generally use copper materials as inner core conductors, inorganic matter magnesium oxide as an insulator for preventing the cables from conducting with the outside, and a sheath is arranged on the outer surface of each cable. In order to protect the safety of the cable, a layer of plastic protection device is arranged on the outer surface of the cable; in some special places, smoke and halogen are required, and a low-smoke halogen-free sheath is added on the outer surface of the cable. Therefore, the mineral insulated cable is particularly suitable for places with severe environment, and can be effectively prevented from being damaged under the condition of higher requirement on safety. However, the mineral insulated cable has high cost and difficult construction process, so the mineral insulated cable has not been widely popularized in China.

The flexible fireproof cable uses a copper wire as an intermediate conductor, materials such as mica and the like are used as insulators in order to prevent electric leakage of the cable, and after mineral compounds are filled, a glass cloth bag is used for wrapping, and finally, a halogen-free low-smoke sheath is covered. The flexible fireproof cable has strong high-temperature resistance and fireproof performance, overcomes the defects of a rigid mineral insulated cable, such as easy moisture absorption or inconvenience in installation, construction and maintenance, and the like, also overcomes the problems of low yield, complex process flow and the like, and has wide development prospect and more market demands in the cable application market. However, after the national new code building design fire protection code GF 50016-.

In consideration of better guarantee of personal and property safety and huge market demand of fireproof cables, a novel composite insulated flexible cable appears besides a rigid mineral insulated cable and a flexible fireproof cable. The structure of the novel composite insulation flexible cable adopts double-layer composite insulation to replace magnesium oxide mineral insulation.

The thickness of the double-layer composite insulation needs to be carefully selected, and when the thickness of the cable guide core is too thin relative to the thickness of the two insulation layers, the temperature field in the cable can be changed along with the change of the thermal physical property of the cable guide core. The lead core of the cable is thin and has small sectional area, so that the resistance of the cable in unit length is increased, the lead core loss of the cable in a power-on state is increased, and more heat is released; and the size of the two insulating layers is increased, so that the heat preservation effect of the cable is enhanced, and the heat generated by the ohmic heat effect of the cable guide core is not released. So that an excessively thin cable core relative to the two insulating layers leads to a temperature increase of the cable core in the steady state; when the cable guide core is too thick relative to the two insulating layers, the insulating effect is affected; the cable core is too thin or too thick relative to the two insulating layers and is in a dangerous state under normal current-carrying capacity.

Disclosure of Invention

The invention aims to provide a preparation method of an insulated cable with a fireproof function, which avoids the problems that the cable conductor core is too thin relative to the thickness of two insulating layers, so that the resistance of the cable per unit length is increased and the power utilization is dangerous; the problem of the cable lead the core for two-layer insulating layer thickness too thick and lead to the insulating nature of cable not enough, the power consumption danger has been avoided.

In order to achieve the above object, the present invention provides a method for preparing an insulated cable with a fire-proof function, comprising: step a: the copper alloy after smelting is filled with protective gas and then is subjected to down-lead continuous casting, the diameter of a down-lead rod is d, and the adopted cooling mode is air cooling; carrying out homogenization treatment on the copper alloy rod with the diameter d after the down-leading continuous casting in an annealing furnace; step b: drawing the homogenized copper alloy rod to a preset copper alloy wire diameter AD through a continuous drawing and continuous annealing multi-channel wire drawing machine; the annealing current of the continuous-drawing continuous-annealing multi-channel wire drawing machine is I, and the annealing wire diameter is BD; wherein the annealing current is in direct proportion to the square of the diameter AD of the preset copper alloy wire; step c: preparing a conductive core with the diameter of D and the resistivity of P by twisting and untwisting a copper alloy wire; step d: c, extruding the inner insulating material and the guide core in the step c in a single-screw extruder to form a first cable, wherein the inner insulating material forms an inner insulating layer; step e: adding a fire retardant and halogen-free low-smoke cross-linked polyolefin into a high-speed mixer, and uniformly stirring to form a fire-proof insulating mixture, wherein the fire-proof insulating mixture is used for preparing a fire-proof layer; the fireproof layer and the outer insulating layer are processed and formed by a plastic extruding machine through the working procedures of paying off, tensioning, preheating, plastic extruding, gluing, cooling and winding and arranging wires; step f: c, forming the fireproof layer and the outer insulating layer obtained in the step d through chemical crosslinking to obtain the insulating cable with the fireproof function; wherein, in step D, the total insulation layer thickness C is determined according to the diameter D of the guide core; selecting a thickness A of the inner insulating layer based on the total insulating layer thickness C; in step f, a thickness B of the outer insulating layer is determined based on the thickness a of the inner insulating layer.

In some embodiments of the present application, when determining the total insulation layer thickness C according to the diameter D of the conductive core, a diameter matrix D0 of preset conductive cores is preset, and D0 (D1, D2, D3, D4) is set, where D1 is the diameter of a first preset conductive core, D2 is the diameter of a second preset conductive core, D3 is the diameter of a third preset conductive core, and D4 is the diameter of a fourth preset conductive core, where D1 < D2 < D3 < D4; presetting a preset total insulation layer thickness matrix C0, and setting C0 (C1, C2, C3 and C4), wherein C1 is the thickness of a first preset total insulation layer, C2 is the thickness of a second preset total insulation layer, C3 is the thickness of a third preset total insulation layer, C4 is the thickness of a fourth preset total insulation layer, and C1 is more than C2 and more than C3 is more than C4; setting the total insulating layer thickness C according to the relation between the diameter D of the guide core and the diameter of each preset guide core: when D < D1, selecting the first preset total insulation layer thickness C1 as the total insulation layer thickness C; when D1 is not less than D < D2, selecting the second preset total insulation layer thickness C2 as the total insulation layer thickness C; when D2 is not less than D < D3, selecting the third preset total insulation layer thickness C3 as the total insulation layer thickness C; when D3 is larger than or equal to D < D4, the fourth preset total insulation layer thickness C4 is selected as the total insulation layer thickness C.

In some embodiments of the present application, when determining the thickness a of the inner insulating layer based on the total insulating layer thickness C, a predetermined inner insulating layer thickness matrix a0 is preset, and a0 (a 1, a2, A3, a 4) is set, where a1 is the thickness of the first predetermined inner insulating layer, a2 is the thickness of the second predetermined inner insulating layer, A3 is the thickness of the third predetermined inner insulating layer, and a4 is the thickness of the fourth predetermined inner insulating layer, where a1 < a2 < A3 < a 4; when determining the thickness B of the outer insulating layer based on the thickness a of the inner insulating layer, presetting a thickness matrix B0 of the outer insulating layer, and setting B0 (B1, B2, B3, B4), where B1 is the thickness of a first preset outer insulating layer, B2 is the thickness of a second preset outer insulating layer, B3 is the thickness of a third preset outer insulating layer, and B4 is the thickness of a fourth preset outer insulating layer, where B1 > B2 > B3 > B4; setting the thickness B of the outer insulating layer according to the relation between the thickness A of the inner insulating layer and the thickness of each preset inner insulating layer: when A is less than A1, selecting the thickness B1 of a first preset outer insulating layer as the thickness B of the outer insulating layer; when A1 is more than or equal to A and less than A2, selecting the thickness B2 of the second preset outer insulating layer as the thickness B of the outer insulating layer; when A2 is more than or equal to A and less than A3, selecting the third preset outer insulation layer thickness B3 as the outer insulation layer thickness B; and when A3 is more than or equal to A < A4, selecting the fourth preset outer insulation layer thickness B4 as the outer insulation layer thickness B.

In some embodiments of the present application, in step e, a fire-retardant layer fire-retardant rating F is determined in real time, and a fire-retardant layer fire-retardant rating matrix F0, F0 (F1, F2, F3, F4, F5) is preset, where F1 is a first preset fire-retardant layer fire-retardant rating, F2 is a second preset fire-retardant layer fire-retardant rating, F3 is a third preset fire-retardant layer fire-retardant rating, F4 is a fourth preset fire-retardant layer fire-retardant rating, F5 is a fifth preset fire-retardant layer fire-retardant rating, and F1 < F2 < F3 < F4 < F5; the fire-proof insulation mixing agent adding method is characterized by also comprising a preset fire-proof insulation mixing agent adding amount matrix G, G (G1, G2, G3, G4 and G5), wherein G1 is the adding amount of a first preset fire-proof insulation mixing agent, G2 is the adding amount of a second preset fire-proof insulation mixing agent, G3 is the adding amount of a third preset fire-proof insulation mixing agent, G4 is the adding amount of a fourth preset fire-proof insulation mixing agent, G5 is the adding amount of a fifth preset fire-proof insulation mixing agent, and G1 is more than G2 is more than G3 is more than G4 is more than G5; when F is less than F1, selecting the adding amount of the first preset fireproof insulating mixing agent as the adding amount of an actual fireproof insulating mixing agent; when F is not less than F1 and is less than F2, selecting the addition amount of the second preset fireproof insulating mixing agent as the addition amount of the actual fireproof insulating mixing agent; when F is not less than F2 and is less than F3, selecting the addition amount of the third preset fireproof insulating mixing agent as the addition amount of the actual fireproof insulating mixing agent; when F is not less than F3 and is less than F4, selecting the addition amount of the fourth preset fireproof insulating mixing agent as the addition amount of an actual fireproof insulating mixing agent; and when F is not less than F4 and is less than F5, selecting the addition amount of the fifth preset fireproof insulating mixing agent as the addition amount of the actual fireproof insulating mixing agent.

In some embodiments of the present application, the diameter D of the conductive core is determined before determining the total insulation layer thickness C of the thickness a of the inner insulation layer and the thickness B of the outer insulation layer from the diameter D of the conductive core; in step a, a diameter matrix d0 of the preset lower guide rods is preset, and d0 (d 1, d2, d3 and d 4) is set, wherein d1 is the diameter of the first preset lower guide rod, d2 is the diameter of the second preset lower guide rod, d3 is the diameter of the third preset lower guide rod, and d4 is the diameter of the fourth preset lower guide rod, wherein d1 < d2 < d3 < d 4; setting the diameter D of the guide core according to the relation between the thickness A of the inner insulating layer and the diameter of each preset lower guide rod: when D < D1, selecting the diameter D1 of the first preset guide core as the diameter D of the guide core; when D1 is larger than or equal to D < D2, the diameter D2 of the second preset guide core is selected as the diameter D of the guide core; when D2 is not less than D < D3, the diameter D3 of the third preset guide core is selected as the diameter D of the guide core; when D3 is not less than D < D4, the diameter D4 of the fourth preset guide core is selected as the diameter D of the guide core.

In some embodiments of the present application, in step b, the predetermined copper alloy wire diameter matrix D0 is preset, and AD0 (AD 1, AD2, AD3, AD 4) is set, where AD1 is the first predetermined copper alloy wire diameter, AD2 is the second predetermined copper alloy wire diameter, AD3 is the third predetermined copper alloy wire diameter, and AD4 is the fourth predetermined copper alloy wire diameter, where AD1 < AD2 < AD3 < AD 4; presetting an annealing wire diameter matrix D0, and setting BD0 (BD 1, BD2, BD3 and BD 4), wherein BD1 is a first preset annealing wire diameter, BD2 is a second preset annealing wire diameter, BD3 is a third preset annealing wire diameter, and BD4 is a fourth preset annealing wire diameter, wherein BD1 < BD2 < BD3 < BD 4; and setting the annealing wire diameter BD according to the relation between the diameter AD of the copper alloy wire and the diameters of the preset copper alloy wires: when AD is less than or equal to AD1, selecting the first preset annealing wire diameter BD1 as the annealing wire diameter BD; when AD1 is more than AD and less than or equal to AD2, selecting the second preset annealing line diameter BD2 as the annealing line diameter BD; when AD2 is more than AD and less than or equal to AD3, selecting the third preset annealing wire diameter BD3 as the annealing wire diameter BD; and when AD3 is less than AD and less than or equal to AD4, selecting the fourth preset annealing line diameter BD4 as the annealing line diameter BD.

In some embodiments of the present application, in step b, an annealing current I corresponding to the preset annealing line diameter is selected according to the annealing line diameter BD, and a corresponding annealing current matrix I0 is preset according to the annealing line diameter matrix BD0, and I0 (I1, I2, I3, I4) is set, where I1 is a first preset annealing current, is an annealing current corresponding to the first preset annealing line diameter BD1, I2 is a second preset annealing current, is an annealing current corresponding to the second preset annealing line diameter BD2, I3 is a third preset annealing current, is an annealing current corresponding to the third preset annealing line diameter BD3, I4 is a fourth preset annealing current, is an annealing current corresponding to the fourth preset annealing line diameter BD4, where I1 < I2 < I3 < I4; monitoring the annealing current I in real time, and adjusting the annealing current I according to the relation between the annealing current I and each preset annealing current: when the annealing wire diameter BD is the first preset annealing wire diameter BD1, and I is less than I1, the annealing current I is increased to the first preset annealing current I1, and when I = I1, the annealing current I is not adjusted; when I > I1, reducing the annealing current I to the first preset annealing current I1; when the annealing wire diameter BD is the second preset annealing wire diameter BD2, and I is less than I2, increasing the annealing current I to the first preset annealing current I2, and when I = I2, not adjusting the annealing current I; when I > I2, reducing the annealing current I to the first preset annealing current I2; when the annealing wire diameter BD is the third preset annealing wire diameter BD3, and I is less than I3, increasing the annealing current I to the first preset annealing current I3, and when I = I3, not adjusting the annealing current I; when I > I3, reducing the annealing current I to the first preset annealing current I3; when the annealing wire diameter BD is the fourth preset annealing wire diameter BD4, and I is less than I4, increasing the annealing current I to the first preset annealing current I4, and when I = I4, not adjusting the annealing current I; when I > I4, the annealing current I is reduced to the first preset annealing current I4.

The application provides an insulating type cable with fire prevention function, this cable adopt the preparation method processing of insulating type cable with fire prevention function is made, wherein, lead the core and crowded package outward have the internal insulation layer forms first cable, one and more first cable is crowded package outward by interior outside to in proper order has flame retardant coating, external insulation layer.

In some embodiments of the present application, the first cable conductors have filler disposed therebetween in parallel and spaced relation.

In some embodiments of the application, the insulating cable with the fireproof function is coated with glass fiber and embossed copper pipe sheaths from inside to outside in sequence.

The invention discloses a preparation method of an insulated cable with a fireproof function, which has the following technical effects compared with the prior art: the preparation accuracy of the diameter of the guide core is improved, and the use safety problem of the cable is avoided by accurately determining the thickness of the inner and outer insulating layers; and the fireproof effect of the cable is improved by additionally arranging the grade of the fireproof layer.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.

Fig. 1 is a flowchart of a method for manufacturing an insulated cable with a fire-proof function according to an embodiment of the present invention.

Detailed Description

The following detailed description of embodiments of the present invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

In the description of the present application, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present application and simplifying the description, but do not indicate or imply that the referred device or element must have a particular orientation, be constructed in a particular orientation, and be operated, and thus should not be construed as limiting the present application.

The terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless otherwise specified.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

As shown in fig. 1, this embodiment discloses a method for preparing an insulated cable with a fire-proof function, including: step a: performing down-drawing continuous casting on the copper alloy after smelting is finished after protective gas is filled, wherein the down-drawing speed is V, the dwell time is t, the diameter of a down-drawing rod is d, and the adopted cooling mode is air cooling; carrying out homogenization treatment on the copper alloy rod with the diameter d after the down-leading continuous casting in an annealing furnace; step b: drawing the homogenized copper alloy rod to a preset copper alloy wire diameter AD through a continuous drawing and continuous annealing multi-channel wire drawing machine; the annealing current of the continuous drawing and continuous annealing multi-channel wire drawing machine is I, and the annealing wire diameter is BD; wherein the annealing current is in direct proportion to the square of the diameter AD of the preset copper alloy wire; step c: preparing a conductive core with the diameter of D and the resistivity of P by twisting and untwisting a copper alloy wire; step d: c, extruding an inner insulating material and the guide core in the step c in a single-screw extruder to form a first cable, wherein the inner insulating material forms an inner insulating layer; step e: adding the fire retardant and the halogen-free low-smoke cross-linked polyolefin into a high-speed mixer, and uniformly stirring to form a fire-proof insulating mixture, wherein the fire-proof insulating mixture is used for preparing a fire-proof layer; the fireproof layer and the outer insulating layer are processed and formed by a plastic extruding machine through the working procedures of paying off, tensioning, preheating, plastic extruding, gluing, cooling and winding and arranging wires; step f: c, forming the fireproof layer and the outer insulating layer obtained in the step d through chemical crosslinking to obtain the insulating cable with the fireproof function; in step D, determining the total insulation layer thickness C of the cable according to the diameter D of the guide core; selecting a thickness A of the inner insulating layer based on the total insulating layer thickness C; in step f, a thickness B of the outer insulating layer is determined based on the thickness a of the inner insulating layer.

It can be understood that the above embodiment selects the corresponding total insulation layer thickness C for the conductive cores with different diameters D, and then selects the corresponding thickness a of the inner insulation layer according to the total insulation layer thickness C, thereby determining the thickness B of the outer insulation layer. The total insulation layer thickness C of the cable is determined according to the diameter D of the guide core, so that the problems that the unit length resistance of the cable is increased and the electricity utilization risk is caused due to the fact that the thickness of the guide core of the cable is too thin relative to the thickness of two insulation layers are solved; the problem of the cable lead the core for two-layer insulation thickness too thick and lead to the insulating nature of cable not enough, the power consumption danger is avoided. In addition, the insulating cable with the fireproof function has the advantages that the mica tape is used as the material in the inner insulating layer, the 4-crosslinked polyethylene insulating layer is used as the outer insulating layer, the crosslinked polyethylene cannot be decomposed and carbonized at the temperature of below 200 ℃, the long-term working temperature can reach 90 ℃, the heat resistance is superior to that of polyvinyl chloride and polyethylene, and the insulating effect can be effectively improved.

It should be noted that the above solution of the preferred embodiment is only one specific implementation proposed in the present application, and those skilled in the art can select other insulating materials and fire-retardant agents according to practical situations, which does not affect the protection scope of the present application.

According to some embodiments of the present application, when determining the total insulation layer thickness C according to the diameter D of the conductive core, a diameter matrix D0 of the preset conductive cores is preset, and D0 (D1, D2, D3, D4) is set, wherein D1 is the diameter of the first preset conductive core, D2 is the diameter of the second preset conductive core, D3 is the diameter of the third preset conductive core, and D4 is the diameter of the fourth preset conductive core, wherein D1 < D2 < D3 < D4; presetting a preset total insulation layer thickness matrix C0, and setting C0 (C1, C2, C3 and C4), wherein C1 is the thickness of a first preset total insulation layer, C2 is the thickness of a second preset total insulation layer, C3 is the thickness of a third preset total insulation layer, C4 is the thickness of a fourth preset total insulation layer, and C1 is more than C2 and more than C3 is more than C4; setting the total insulation layer thickness C according to the relation between the diameter D of the guide core and the diameter of each preset guide core: when D is less than D1, selecting a first preset total insulation layer thickness C1 as the total insulation layer thickness C; when D1 is more than or equal to D and less than D2, selecting the thickness C2 of a second preset total insulating layer as the thickness C of the total insulating layer; when D2 is more than or equal to D and less than D3, selecting the third preset total insulation layer thickness C3 as the total insulation layer thickness C; and when D3 is more than or equal to D < D4, selecting a fourth preset total insulation layer thickness C4 as the total insulation layer thickness C.

It is understood that the above-described embodiment can improve the accuracy of the selection of the total insulation layer thickness C by setting the total insulation layer thickness C according to the relationship between the diameter D of the conductive core and the diameter of each preset conductive core.

It should be noted that the above solution of the preferred embodiment is only a specific implementation manner proposed in the present application, and a person skilled in the art may select and set the diameter matrix D0 of the predetermined guide core and the total insulation layer thickness matrix C0 according to practical situations, which does not affect the protection scope of the present application.

In some embodiments of the present application, in determining the thickness a of the inner insulating layer based on the total insulating layer thickness C, a thickness matrix a0 of the preset inner insulating layers is preset, and a0 (a 1, a2, A3, a 4) is set, where a1 is the thickness of the first preset inner insulating layer, a2 is the thickness of the second preset inner insulating layer, A3 is the thickness of the third preset inner insulating layer, and a4 is the thickness of the fourth preset inner insulating layer, where a1 < a2 < A3 < a 4; when the thickness B of the outer insulating layer is determined based on the thickness A of the inner insulating layer, presetting a thickness matrix B0 of the outer insulating layer, and setting B0 (B1, B2, B3 and B4), wherein B1 is the thickness of a first preset outer insulating layer, B2 is the thickness of a second preset outer insulating layer, B3 is the thickness of a third preset outer insulating layer, and B4 is the thickness of a fourth preset outer insulating layer, wherein B1 > B2 > B3 > B4; setting the thickness B of the outer insulating layer according to the relation between the thickness A of the inner insulating layer and the thickness of each preset inner insulating layer: when A is less than A1, selecting the thickness B1 of the first preset outer insulating layer as the thickness B of the outer insulating layer; when A is greater than or equal to A1 and is less than A2, selecting the thickness B2 of the second preset outer insulating layer as the thickness B of the outer insulating layer; when A is greater than or equal to A2 and is less than A3, selecting the thickness B3 of a third preset outer insulating layer as the thickness B of the outer insulating layer; and when A3 is more than or equal to A and less than A4, selecting the thickness B4 of the fourth preset outer insulating layer as the thickness B of the outer insulating layer.

It can be understood that, in the above embodiment, the thickness a of the inner insulating layer can be better determined by presetting the thickness matrix a0 of the preset inner insulating layer, wherein the thickness of the inner insulating layer accounts for 25% -50% of the total thickness of the insulating layer, which can better improve the insulation of the first cable, and the value of the thickness matrix a0 of the preset inner insulating layer is in the range of 0.25C ≦ a ≦ 0.50C; the thickness B of the outer insulating layer is set according to the relation between the thickness A of the inner insulating layer and the thickness of each preset inner insulating layer, so that the accuracy of selecting the thickness B of the outer insulating layer can be improved, and the phenomenon that the insulation of the cable is influenced due to too low thickness B of the outer insulating layer is avoided.

It should be noted that the above solution of the preferred embodiment is only a specific implementation manner proposed in the present application, and those skilled in the art can select and set the preset thickness matrix a0 of the inner insulating layer and the preset thickness matrix B0 of the outer insulating layer according to practical situations, which does not affect the protection scope of the present application.

In some embodiments of the present application, in step e, a fire-retardant layer fire-retardant rating F is determined in real time, and a fire-retardant layer fire-retardant rating matrix F0, F0 (F1, F2, F3, F4, F5) is preset, where F1 is a first preset fire-retardant layer fire-retardant rating, F2 is a second preset fire-retardant layer fire-retardant rating, F3 is a third preset fire-retardant layer fire-retardant rating, F4 is a fourth preset fire-retardant layer fire-retardant rating, F5 is a fifth preset fire-retardant layer fire-retardant rating, and F1 < F2 < F3 < F4 < F5; the fire-proof insulation mixing agent adding method is characterized by also comprising a preset fire-proof insulation mixing agent adding amount matrix G and G (G1, G2, G3, G4 and G5), wherein G1 is the adding amount of a first preset fire-proof insulation mixing agent, G2 is the adding amount of a second preset fire-proof insulation mixing agent, G3 is the adding amount of a third preset fire-proof insulation mixing agent, G4 is the adding amount of a fourth preset fire-proof insulation mixing agent, G5 is the adding amount of a fifth preset fire-proof insulation mixing agent, G1 is more than G2 is more than G3 is more than G4 is more than G5, and when the adding amount of the fire-proof insulation mixing agent is determined, the adding amount of an actual fire-proof insulation mixing agent is set according to the relation between a fire-proof grade F of a fire-proof layer determined in real time and the fire-proof grade of the fire-proof layer; when F is less than F1, selecting the adding amount of the first preset fireproof insulating mixing agent as the adding amount of the actual fireproof insulating mixing agent; when F is not less than F1 and is less than F2, selecting the addition amount of the second preset fireproof insulating mixing agent as the addition amount of the actual fireproof insulating mixing agent; when F is not less than F2 and is less than F3, selecting the addition amount of the third preset fireproof insulating mixing agent as the addition amount of the actual fireproof insulating mixing agent; when F is not less than F3 and is less than F4, selecting the addition amount of a fourth preset fireproof insulating mixing agent as the addition amount of an actual fireproof insulating mixing agent; and when F is not less than F4 and is less than F5, selecting the addition amount of the fifth preset fireproof insulating mixing agent as the addition amount of the actual fireproof insulating mixing agent.

It can be understood that, in the above embodiment, the adding amount of the actual fireproof insulation mixing agent is set according to the relation between the fireproof grade F of the fireproof layer determined in real time and the fireproof grade of the preset fireproof layer when the adding amount of the fireproof insulation mixing agent is determined through the preset fireproof grade matrix F0 of the fireproof layer and the preset adding amount matrix G of the fireproof insulation mixing agent; the addition of the fire-proof insulating mixing agent can be accurately controlled, the fire-proof performance of the cable is prevented from being influenced by the excessively low addition of the fire-proof insulating mixing agent, and the waste of the fire-proof insulating mixing agent caused by the excessively high addition of the fire-proof insulating mixing agent is avoided.

It should be noted that the above solution of the preferred embodiment is only a specific implementation manner proposed in the present application, and a person skilled in the art may select to set the preset fire-protection level matrix F0 of the fire-protection layer and the preset addition amount matrix G of the fire-protection insulation mixture according to actual situations, which does not affect the protection scope of the present application.

In some embodiments of the present application, the diameter D of the conductive core is determined before the total insulation layer thickness C of the thickness a of the inner insulation layer and the thickness B of the outer insulation layer is determined from the diameter D of the conductive core; in the step a, a diameter matrix d0 of the preset lower guide rods is preset, and d0 (d 1, d2, d3 and d 4) is set, wherein d1 is the diameter of the first preset lower guide rod, d2 is the diameter of the second preset lower guide rod, d3 is the diameter of the third preset lower guide rod, and d4 is the diameter of the fourth preset lower guide rod, wherein d1 < d2 < d3 < d 4; the diameter D of the guide core is set according to the relation between the thickness A of the inner insulating layer and the diameter of each preset lower guide rod: when D is less than D1, selecting the diameter D1 of the first preset guide core as the diameter D of the guide core; when D1 is not less than D and is less than D2, the diameter D2 of the second preset guide core is selected as the diameter D of the guide core; when D2 is not less than D and is less than D3, the diameter D3 of the third preset guide core is selected as the diameter D of the guide core; when D3 is larger than or equal to D < D4, the diameter D4 of the fourth preset guide core is selected as the diameter D of the guide core.

It can be understood that, in the above embodiment, in order to improve the accuracy of the preparation of the core diameter D, the diameter D of the core is set according to the relationship between the thickness a of the inner insulating layer and the diameter of each of the preset lower leads, so that the accuracy of the preparation of the core diameter D can be effectively improved.

It should be noted that the above solution of the preferred embodiment is only a specific implementation manner proposed in the present application, and a person skilled in the art may select to set the diameter matrix d0 of the preset down-lead rod according to practical situations, which does not affect the protection scope of the present application.

In some embodiments of the present application, in step b, the predetermined copper alloy wire diameter matrix D0 is preset, and AD0 (AD 1, AD2, AD3, AD 4) is set, where AD1 is the first predetermined copper alloy wire diameter, AD2 is the second predetermined copper alloy wire diameter, AD3 is the third predetermined copper alloy wire diameter, and AD4 is the fourth predetermined copper alloy wire diameter, where AD1 < AD2 < AD3 < AD 4; presetting an annealing wire diameter matrix D0, and setting BD0 (BD 1, BD2, BD3 and BD 4), wherein BD1 is a first preset annealing wire diameter, BD2 is a second preset annealing wire diameter, BD3 is a third preset annealing wire diameter, and BD4 is a fourth preset annealing wire diameter, wherein BD1 < BD2 < BD3 < BD 4; and setting the annealing wire diameter BD according to the relation between the diameter AD of the copper alloy wire and the diameters of the preset copper alloy wires: when AD is less than or equal to AD1, selecting a first preset annealing wire diameter BD1 as the annealing wire diameter BD; when AD1 is more than AD and less than or equal to AD2, selecting a second preset annealing wire diameter BD2 as an annealing wire diameter BD; when AD2 is more than AD and less than or equal to AD3, selecting a third preset annealing wire diameter BD3 as an annealing wire diameter BD; and when AD3 is more than AD and less than or equal to AD4, selecting a fourth preset annealing wire diameter BD4 as the annealing wire diameter BD.

It can be understood that, in order to further improve the accuracy of the diameter D of the core, the above embodiment improves the accuracy of the diameter AD of the copper alloy wire by presetting the diameter AD of the copper alloy wire subjected to the continuous drawing and continuous annealing process and adjusting the annealing current.

It should be noted that the above solution of the preferred embodiment is only a specific implementation manner proposed in the present application, and those skilled in the art can select and set the pre-set copper alloy wire diameter matrix AD0 and the annealing wire diameter matrix BD0 according to practical situations, which does not affect the protection scope of the present application.

In some embodiments of the present application, in order to improve the accuracy of adjusting the annealing current, in step b, an annealing current I corresponding to a predetermined annealing line diameter is selected according to the annealing line diameter BD, and a corresponding annealing current matrix I0 is preset according to the annealing line diameter matrix BD0, and I0 (I1, I2, I3, I4) is set, where I1 is a first predetermined annealing current corresponding to the first predetermined annealing line diameter BD1, I2 is a second predetermined annealing current corresponding to the second predetermined annealing line diameter BD2, I3 is a third predetermined annealing current corresponding to the third predetermined annealing line diameter BD3, I4 is a fourth predetermined annealing current corresponding to the fourth predetermined annealing line diameter BD4, where I1 < I2 < I3 < I4; monitoring the annealing current I in real time, and adjusting the annealing current I according to the relation between the annealing current I and each preset annealing current: when the annealing wire diameter BD is a first preset annealing wire diameter BD1, and I is less than I1, the annealing current I is increased to a first preset annealing current I1, and when I = I1, the annealing current I is not adjusted; when I is larger than I1, reducing the annealing current I to a first preset annealing current I1; when the annealing wire diameter BD is the second preset annealing wire diameter BD2, when I is less than I2, the annealing current I is increased to the first preset annealing current I2, and when I = I2, the annealing current I is not adjusted; when I is larger than I2, reducing the annealing current I to a first preset annealing current I2; when the annealing wire diameter BD is a third preset annealing wire diameter BD3, when I is less than I3, increasing the annealing current I to a first preset annealing current I3, and when I = I3, not adjusting the annealing current I; when I is larger than I3, reducing the annealing current I to a first preset annealing current I3; when the annealing wire diameter BD is a fourth preset annealing wire diameter BD4, and I is less than I4, increasing the annealing current I to a first preset annealing current I4, and when I = I4, not adjusting the annealing current I; when I > I4, the annealing current I is reduced to a first preset annealing current I4.

It can be understood that, in the above embodiment, the preset annealing current I corresponding to the preset annealing line diameter is selected according to the annealing line diameter BD, and the annealing current I is adjusted according to the relationship between the annealing current I and each preset annealing current, so as to improve the accuracy of adjusting the annealing current.

It should be noted that the above solution of the preferred embodiment is only a specific implementation manner proposed in the present application, and a person skilled in the art may select to set the preset annealing current matrix I0 according to practical situations, which does not affect the protection scope of the present application.

The utility model provides an insulating type cable with fire prevention function, this cable adopt the preparation method processing of insulating type cable with fire prevention function to make, wherein, the outer crowded package of lead core has the internal insulation layer to form first cable, and the crowded package of flame retardant coating, outer insulating layer in proper order outside one or more first cables is from inside to outside.

It can be understood that, the above embodiment improves the insulation of the first cable by extruding the inner insulation layer outside the conductive core for insulation; the insulating cable with the fireproof function comprises one or more first cables, and the fireproof layer and the outer insulating layer are sequentially extruded outside the one or more first cables from inside to outside, so that the insulativity of the cable can be further improved, and the fireproof performance of the cable is improved.

In some embodiments of the present application, a filler is disposed between the first cable conductors in parallel and spaced relation to each other.

It can be understood that when the embodiment is in a fire scene, the glass fiber has a flame retardant effect, and the corrugated copper pipe sheath forms a physical first defense line to protect the internal structure from being damaged by external force. In addition, in the project environment that the copper sheath is easily corroded, the low-smoke halogen-free high-flame-retardant polyolefin outer sheath can be added.

It should be noted that the above solution of the preferred embodiment is only one specific implementation proposed in the present application, and those skilled in the art can select other outer sheaths according to practical situations, which does not affect the protection scope of the present application.

In summary, the invention discloses a preparation method of an insulated cable with a fireproof function, and compared with the prior art, the preparation method has the following technical effects: the diameter preparation accuracy of the guide core is improved, and the use safety problem of the cable is avoided by accurately determining the thickness of the inner and outer insulating layers; and the fireproof effect of the cable is improved by additionally arranging the grade of the fireproof layer.

It should be understood that, although the steps in the flowcharts of the embodiments of the present invention are shown in sequence as indicated by the arrows, the steps are not necessarily performed in sequence as indicated by the arrows. The steps are not performed in the exact order shown and described, and may be performed in other orders, unless explicitly stated otherwise. Moreover, at least a portion of steps in various embodiments may include multiple sub-steps or multiple stages that are not necessarily performed at the same time, but may be performed at different times, and the order of performing the sub-steps or stages is not necessarily sequential, but may be performed alternately or alternatingly with other steps or at least a portion of the sub-steps or stages of other steps.

Those of ordinary skill in the art will understand that: although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that various changes, modifications and substitutions can be made without departing from the spirit and scope of the invention as defined by the appended claims. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A preparation method of an insulated cable with a fireproof function is characterized by comprising the following steps:

step a: the copper alloy after smelting is filled with protective gas and then is subjected to down-lead continuous casting, the diameter of a down-lead rod is d, and the adopted cooling mode is air cooling; carrying out homogenization treatment on the copper alloy rod with the diameter d after the down-leading continuous casting in an annealing furnace;

step b: drawing the homogenized copper alloy rod to a preset copper alloy wire diameter AD through a continuous drawing and continuous annealing multi-channel wire drawing machine; the annealing current of the continuous-drawing continuous-annealing multi-channel wire drawing machine is I, and the annealing wire diameter is BD; wherein the annealing current is in direct proportion to the square of the diameter AD of the preset copper alloy wire;

step c: preparing a conductive core with the diameter of D and the resistivity of P by twisting and untwisting a copper alloy wire;

step d: c, extruding the inner insulating material and the guide core in the step c in a single-screw extruder to form a first cable, wherein the inner insulating material forms an inner insulating layer;

step e: adding a fire retardant and halogen-free low-smoke cross-linked polyolefin into a high-speed mixer, and uniformly stirring to form a fire-proof insulating mixture, wherein the fire-proof insulating mixture is used for preparing a fire-proof layer; the fireproof layer and the outer insulating layer are processed and formed by a plastic extruding machine through the working procedures of paying off, tensioning, preheating, plastic extruding, gluing, cooling and winding and arranging wires;

step f: c, forming the fireproof layer and the outer insulating layer obtained in the step d through chemical crosslinking to obtain the insulating cable with the fireproof function; wherein the content of the first and second substances,

in the step D, determining the total insulating layer thickness C according to the diameter D of the guide core; selecting a thickness A of the inner insulating layer based on the total insulating layer thickness C;

in the step f, a thickness B of the outer insulating layer is determined based on the thickness a of the inner insulating layer.

2. The method for preparing an insulated cable having a flameproof function of claim 1, wherein, when determining the total insulation layer thickness C according to the diameter D of the conductive cores, a diameter matrix D0 of preset conductive cores is preset, and D0 (D1, D2, D3, D4) is set, wherein D1 is the diameter of a first preset conductive core, D2 is the diameter of a second preset conductive core, D3 is the diameter of a third preset conductive core, and D4 is the diameter of a fourth preset conductive core, wherein D1 < D2 < D3 < D4;

presetting a preset total insulation layer thickness matrix C0, and setting C0 (C1, C2, C3 and C4), wherein C1 is the thickness of a first preset total insulation layer, C2 is the thickness of a second preset total insulation layer, C3 is the thickness of a third preset total insulation layer, C4 is the thickness of a fourth preset total insulation layer, and C1 is more than C2 and more than C3 is more than C4;

setting the total insulating layer thickness C according to the relation between the diameter D of the guide core and the diameter of each preset guide core:

when D < D1, selecting the first preset total insulation layer thickness C1 as the total insulation layer thickness C;

when D1 is not less than D < D2, selecting the second preset total insulation layer thickness C2 as the total insulation layer thickness C;

when D2 is not less than D < D3, selecting the third preset total insulation layer thickness C3 as the total insulation layer thickness C;

when D3 is larger than or equal to D < D4, the fourth preset total insulation layer thickness C4 is selected as the total insulation layer thickness C.

3. The method for preparing an insulated cable having a flameproof function according to claim 2, wherein, in determining the thickness a of the inner insulating layer based on the total insulating layer thickness C, a thickness matrix a0 of a predetermined inner insulating layer is previously set, a0 (a 1, a2, A3, a 4) is set, wherein a1 is the thickness of a first predetermined inner insulating layer, a2 is the thickness of a second predetermined inner insulating layer, A3 is the thickness of a third predetermined inner insulating layer, and a4 is the thickness of a fourth predetermined inner insulating layer, wherein a1 < a2 < A3 < a 4;

when the thickness B of the outer insulating layer is determined based on the thickness A of the inner insulating layer, presetting a thickness matrix B0 of the outer insulating layer, and setting B0 (B1, B2, B3 and B4), wherein B1 is the thickness of a first preset outer insulating layer, B2 is the thickness of a second preset outer insulating layer, B3 is the thickness of a third preset outer insulating layer, and B4 is the thickness of a fourth preset outer insulating layer, wherein B1 > B2 > B3 > B4;

setting the thickness B of the outer insulating layer according to the relation between the thickness A of the inner insulating layer and the thickness of each preset inner insulating layer:

when A is less than A1, selecting the thickness B1 of a first preset outer insulating layer as the thickness B of the outer insulating layer;

when A1 is more than or equal to A and less than A2, selecting the thickness B2 of the second preset outer insulating layer as the thickness B of the outer insulating layer;

when A2 is more than or equal to A and less than A3, selecting the third preset outer insulation layer thickness B3 as the outer insulation layer thickness B;

and when A3 is more than or equal to A < A4, selecting the fourth preset outer insulation layer thickness B4 as the outer insulation layer thickness B.

4. The method for preparing an insulated cable having a fire prevention function according to claim 1,

in the step e, determining the fire-proof grade F of the fire-proof layer in real time, and presetting a fire-proof grade matrix F0 and F0 (F1, F2, F3, F4 and F5), wherein F1 is a first preset fire-proof grade of the fire-proof layer, F2 is a second preset fire-proof grade of the fire-proof layer, F3 is a third preset fire-proof grade of the fire-proof layer, F4 is a fourth preset fire-proof grade of the fire-proof layer, F5 is a fifth preset fire-proof grade of the fire-proof layer, and F1 is more than F2 and more than F3 and more than F4 and more than F5;

the fireproof insulation composite material is also provided with a preset fireproof insulation mixture adding amount matrix G, G (G1, G2, G3, G4 and G5), wherein G1 is the adding amount of a first preset fireproof insulation mixture, G2 is the adding amount of a second preset fireproof insulation mixture, G3 is the adding amount of a third preset fireproof insulation mixture, G4 is the adding amount of a fourth preset fireproof insulation mixture, G5 is the adding amount of a fifth preset fireproof insulation mixture, and G1 is more than G2 is more than G3 is more than G4 is more than G5;

when the adding amount of the fireproof insulation mixing agent is determined, the adding amount of the actual fireproof insulation mixing agent is set according to the relation between the fireproof grade F of the fireproof layer determined in real time and the fireproof grade of the preset fireproof layer;

when F is less than F1, selecting the adding amount of the first preset fireproof insulating mixing agent as the adding amount of the actual fireproof insulating mixing agent;

when F is not less than F1 and is less than F2, selecting the addition amount of the second preset fireproof insulating mixing agent as the addition amount of the actual fireproof insulating mixing agent;

when F is not less than F2 and is less than F3, selecting the addition amount of the third preset fireproof insulating mixing agent as the addition amount of the actual fireproof insulating mixing agent;

when F is not less than F3 and is less than F4, selecting the addition amount of the fourth preset fireproof insulating mixing agent as the addition amount of the actual fireproof insulating mixing agent;

and when F is not less than F4 and is less than F5, selecting the addition amount of the fifth preset fireproof insulating mixing agent as the addition amount of the actual fireproof insulating mixing agent.

5. The method for preparing an insulated cable having a flameproof function according to claim 2, wherein the diameter D of the conductive core is determined before the total insulation layer thickness C of the thickness a of the inner insulation layer and the thickness B of the outer insulation layer is determined according to the diameter D of the conductive core;

in the step a, a diameter matrix d0 of the preset lower guide rods is preset, and d0 (d 1, d2, d3 and d 4) is set, wherein d1 is the diameter of the first preset lower guide rod, d2 is the diameter of the second preset lower guide rod, d3 is the diameter of the third preset lower guide rod, and d4 is the diameter of the fourth preset lower guide rod, wherein d1 < d2 < d3 < d 4;

setting the diameter D of the guide core according to the relation between the thickness A of the inner insulating layer and the diameter of each preset lower guide rod:

when D < D1, selecting the diameter D1 of the first preset guide core as the diameter D of the guide core;

when D1 is not less than D < D2, selecting the diameter D2 of the second preset guide core as the diameter D of the guide core;

when D2 is not less than D < D3, selecting the diameter D3 of the third preset guide core as the diameter D of the guide core;

when D3 is not less than D < D4, the diameter D4 of the fourth preset guide core is selected as the diameter D of the guide core.

6. The method for preparing an insulated cable with a fireproof function according to claim 1, wherein in step b, a predetermined copper alloy wire diameter matrix AD0 is preset, and AD0 (AD 1, AD2, AD3, AD 4) is set, wherein AD1 is a first predetermined copper alloy wire diameter, AD2 is a second predetermined copper alloy wire diameter, AD3 is a third predetermined copper alloy wire diameter, and AD4 is a fourth predetermined copper alloy wire diameter, wherein AD1 < AD2 < AD3 < AD 4;

presetting an annealing wire diameter matrix BD0, and setting BD0 (BD 1, BD2, BD3 and BD 4), wherein BD1 is a first preset annealing wire diameter, BD2 is a second preset annealing wire diameter, BD3 is a third preset annealing wire diameter, and BD4 is a fourth preset annealing wire diameter, wherein BD1 < BD2 < BD3 < BD 4;

and setting the annealing wire diameter BD according to the relation between the diameter AD of the copper alloy wire and the diameters of the preset copper alloy wires:

when AD is less than or equal to AD1, selecting the first preset annealing wire diameter BD1 as the annealing wire diameter BD;

when AD1 is more than AD and less than or equal to AD2, selecting the second preset annealing wire diameter BD2 as the annealing wire diameter BD;

when AD2 is more than AD and less than or equal to AD3, selecting the third preset annealing line diameter BD3 as the annealing line diameter BD;

and when AD3 is less than AD and less than or equal to AD4, selecting the fourth preset annealing line diameter BD4 as the annealing line diameter BD.

7. The method of claim 6, wherein in step b, an annealing current I corresponding to the predetermined annealing wire diameter is selected according to the annealing wire diameter BD, and a corresponding annealing current matrix I0 is preset according to the annealing wire diameter matrix BD0, and I0 (I1, I2, I3, I4) is set, wherein I1 is a first predetermined annealing current corresponding to the first predetermined annealing wire diameter BD1, I2 is a second predetermined annealing current corresponding to the second predetermined annealing wire diameter BD2, I3 is a third predetermined annealing current, an annealing current corresponding to the third predetermined annealing wire diameter BD3, I4 is a fourth predetermined annealing current, and an annealing current corresponding to the fourth predetermined annealing wire diameter BD4, wherein I1 < I3 < I2 < I4;

monitoring the annealing current I in real time, and adjusting the annealing current I according to the relation between the annealing current I and each preset annealing current:

when the annealing wire diameter BD is the first preset annealing wire diameter BD1, and I is less than I1, increasing the annealing current I to the first preset annealing current I1, and when I = I1, not adjusting the annealing current I; when I > I1, reducing the annealing current I to the first preset annealing current I1;

when the annealing wire diameter BD is the second preset annealing wire diameter BD2, and I is less than I2, increasing the annealing current I to the first preset annealing current I2, and when I = I2, not adjusting the annealing current I; when I > I2, reducing the annealing current I to the first preset annealing current I2;

when the annealing wire diameter BD is the third preset annealing wire diameter BD3, and I is less than I3, increasing the annealing current I to the first preset annealing current I3, and when I = I3, not adjusting the annealing current I; when I > I3, reducing the annealing current I to the first preset annealing current I3;

when the annealing wire diameter BD is the fourth preset annealing wire diameter BD4, and I is less than I4, increasing the annealing current I to the first preset annealing current I4, and when I = I4, not adjusting the annealing current I; when I > I4, the annealing current I is reduced to the first preset annealing current I4.

8. The insulated cable with the fireproof function is characterized by being manufactured by the preparation method of the insulated cable with the fireproof function according to any one of claims 1 to 7, wherein the inner insulating layer is extruded outside the guide core to form the first cable, and the fireproof layer and the outer insulating layer are sequentially extruded outside one or more first cables from inside to outside.

9. The insulated type cable with fire protection function according to claim 8, wherein fillers are placed between the first cable conductors in parallel and spaced apart from each other.

10. The insulated cable with the fireproof function according to claim 8, wherein the insulated cable with the fireproof function is coated with glass fiber and a corrugated copper pipe sheath from inside to outside in sequence.