Profile wire water-blocking conductor design method
阅读说明：本技术 一种型线阻水导体设计方法 (Profile wire water-blocking conductor design method ) 是由 王文超 胡明 赵囿林 于洪淼 叶成 薛建林 谢书鸿 花炜 于 2020-07-06 设计创作，主要内容包括：本发明公开了一种型线阻水导体设计方法,包括如下步骤：步骤100：获取导体截面面积S<Sub>th</Sub>；步骤200：获取单根梯型单丝截面面积S；步骤300：对应获取各层的单根梯型单丝夹角θ＝360/n；步骤400：根据中心圆柱导体直径d<Sub>0</Sub>、S、θ、以及设定的内外角部圆弧倒角半径r<Sub>1</Sub>、r<Sub>2</Sub>获取各层单根所述梯型单丝内外弧边半径R<Sub>1</Sub>、R<Sub>2</Sub>；步骤500：计算当前导体紧压系数η’,并判断是否符合预设导体紧压系数η要求,若不符合要求,调整相关参数并返回上述步骤以重新计算对应参数；步骤600：获取各层所述梯型单丝的宽径比,判断所述宽径比是否符合预设值,若不符合,则调整相关参数。该型线阻水导体设计方法能够有效地解决型线阻水导体结构参数设计困难和制造工艺成型效果不佳的问题。(The invention discloses a method for designing a molded line water-blocking conductor, which comprises the following steps: step 100: obtaining the cross-sectional area S of the conductor th (ii) a Step 200: obtaining the section area S of a single trapezoidal monofilament; step 300: correspondingly obtaining the included angle theta of the single trapezoidal monofilament of each layer as 360/n; step 400: according to the diameter d of the central cylindrical conductor 0 S, theta, and set inside and outside corner circular chamfer radius r 1 、r 2 Obtaining the radius R of the inner arc edge and the outer arc edge of each layer of the trapezoidal monofilament 1 、R 2 500, calculating a current conductor compression coefficient η', judging whether the current conductor compression coefficient meets the requirement of η of a preset conductor compression coefficient, if not, adjusting related parameters and returning to the previous step to recalculate corresponding parameters, 600, obtaining the aspect ratio of each layer of trapezoidal monofilaments, judging whether the aspect ratio meets the preset value, if not, adjusting the related parametersThe water-blocking conductor has the problems of difficult design of structural parameters and poor forming effect of a manufacturing process.)
1. A method for designing a molded line water-blocking conductor is characterized by comprising the following steps:
step 100: according to conductor filament resistivity ρ20Conductor DC resistance R20Obtaining the cross-sectional area S of the conductorth；
Step 200: according to the cross-sectional area S of the conductorthObtaining the section area S of a single trapezoid monofilament by the number N of the trapezoid monofilaments;
step 300: correspondingly obtaining the included angle of the trapezoidal monofilaments of each layer according to the number n of the trapezoidal monofilaments of each layer
Step 400: according to the diameter d of the central cylindrical conductor0The area S of a single trapezoid monofilament, the included angle theta of each trapezoid monofilament, and the set arc chamfer radius r of the inner corner and the outer corner1、r2Obtaining the radius R of the inner arc edge and the outer arc edge of each layer of the trapezoidal monofilament1、R2And in the two adjacent layers of the trapezoidal monofilaments, the radius of the outer arc edge of the inner layer of the trapezoidal monofilament is equal to that of the inner arc edge of the outer layer of the trapezoidal monofilament, and the radius of the inner arc edge of the innermost layer of the trapezoidal monofilament in each layer of the trapezoidal monofilaments is equal to the diameter d of the central cylindrical conductor0Equal;
step 500: according to the diameter D of the middle and outer arc edges of the ladder-shaped monofilaments positioned at the outermost layer in each layer of ladder-shaped monofilamentscAnd the cross-sectional area S of the conductorthCalculating a current conductor compression coefficient η ', judging whether the current conductor compression coefficient η ' meets the requirement of a preset conductor compression coefficient η, if so, executing the next step, and if not, adjusting related parameters according to the deviation of the current conductor compression coefficient η ' relative to the preset conductor compression coefficient η, and returning to the step to recalculate parameters corresponding to the related parameters;
step 600: according to the radius R of the inner arc edge and the outer arc edge of each layer of the trapezoidal monofilament1、R2And obtaining the width-diameter ratio of each layer of trapezoidal monofilaments according to the included angle theta of the trapezoidal monofilaments, judging whether the width-diameter ratio meets a preset value, if not, adjusting related parameters and returning to the step to recalculate the corresponding parameters.
2. The method of designing a molded water-blocking conductor according to claim 1, wherein the step 100 is: calculating the cross-sectional area of the conductor
3. The molded-line water-blocking conductor of claim 2The design method is characterized in that the step 200 is as follows: if the central cylindrical conductor is a round monofilament conductor and the cross-sectional area of the single trapezoidal monofilament is equal to that of the single trapezoidal monofilament, the cross-sectional area of the single trapezoidal monofilament
4. The method of designing a molded water-blocking conductor of claim 3, wherein the step 400 comprises the steps of:
step 410: the radius R of the inner arc edge of the trapezoidal monofilament of each layer1The outer arc edge radius R of the ladder-shaped monofilament of the adjacent inner layer2Equal and inner arc edge radius R in the ladder-shaped monofilament of the innermost layer of the conductor1Diameter d of the central cylindrical conductor0Equal;
step 420: according to the corresponding layers obtained from inside to outside in sequence, the radius R of the inner arc edge in the trapezoidal monofilament1Sequentially calculating the radius R of the outer arc edge of each layer of the trapezoidal monofilament from inside to outside through the following formula2：
Wherein, α1、α2Respectively forming included angles S between the extension line of the side edge of the trapezoidal monofilament and the connecting lines between the circle centers of the inner and outer circular arc chamfers and the circle center of the conductorin、SouRespectively the sector areas S corresponding to the inner and outer arc edges of the trapezoidal monofilament formed by the included angle theta1Removing area for inner corner arc chamfering, S2The area of the arc chamfer of the outer corner is removed.
5. The method of designing a molded water-blocking conductor according to claim 4, wherein the step 500 comprises the steps of:
step 510: calculating the current conductor compression coefficient:
wherein k is4The reduction coefficient of the thickness of the water-blocking material between each layer in the process of twisting the molded line, DiThe diameter of the outer arc edge of each layer of the trapezoidal monofilament is shown, m is the number of layers of the trapezoidal monofilament, and t is the thickness of a water-blocking material;
step 520, judging the current conductor compression coefficient η ' and the preset conductor compression coefficient η, if η ' is not less than η, executing the next step, and if η ' is less than η, increasing the conductor molding coefficient k1The coefficient of elongation of the conductor strand k2Or the coefficient of influence k of the strand resistivity of the conductor3To increase the cross-sectional area S of the conductorthOr increasing the thickness t of the water blocking material and then returning to the step 100.
6. The method of designing a molded water-blocking conductor according to claim 5, wherein the step 600 comprises the steps of:
step 610: calculating the radial length T ═ R of the trapezoidal monofilament2-R1The outer width of the ladder-shaped monofilamentCalculating the width-diameter ratio W/T;
step 620: and judging whether the width-diameter ratio meets a preset value, if not, adjusting the number n of the trapezoidal monofilaments in a single layer or the number m of the trapezoidal monofilaments, and returning to the step 300.
7. The method for designing the molded water-blocking conductor according to claim 6, wherein the pitch ratio of the twisted trapezoidal monofilaments at the inner layer is larger than the pitch ratio of the twisted trapezoidal monofilaments at the outer layer.
8. The method for designing the molded water-blocking conductor according to claim 7, wherein the pitch-diameter ratio of the ladder-shaped monofilaments at the innermost layer is 16-20, and the pitch-diameter ratio of the ladder-shaped monofilaments at the outermost layer is 10-14.
9. The method of claim 3, wherein the central cylindrical conductor is a round monofilament having a diameterWherein t is0The diameter variation of the metal wire caused by the thickness of the water-blocking material.
10. The method of claim 9, wherein the amount of wire diameter variation t caused by the thickness of the water blocking material is determined by the thickness of the wire0The molding coefficient k of the conductor is between 0.04 and 0.06 mm1The value range of (A) is 1.02-1.07; coefficient of elongation of stranded conductor k2The value range of (1.01) to (1.03), and the influence coefficient k of the resistivity after the conductor is stranded3The value range of (A) is 1.005-1.02.
Technical Field
The invention relates to the technical field of conductors, in particular to a method for designing a molded line water-blocking conductor.
Background
With the rapid development of offshore transmission line construction, the problems of saving submarine cable routes, improving submarine cable transmission capacity, saving submarine cable construction and operation cost and the like become more and more concerned in the industry. Practical manufacturing experience has demonstrated that for 2000mm2For large-section submarine cable conductors (square millimeter) and above, the production process and water resistance of the round compacted structure conductor are insufficient, and a special-shaped monofilament stranded conductor structure with high compaction coefficient, small outer diameter and low material consumption is preferably selected. At present, the special-shaped water-blocking conductor mainly adopts two structures of a ladder-shaped monofilament and an SZ-shaped self-locking monofilament, wherein the SZ-shaped monofilament is twisted and compacted, but the problems of high manufacturing process requirement, difficulty in stripping the conductor monofilament and the like exist, the conductor resistance test and the welding repair of a conductor joint after a submarine cable fault are not facilitated, the ladder-shaped wire conductor structure is relatively easy to strip, and the special-shaped water-blocking conductor is applied to related submarine cable projects and has a wide application prospect in high-voltage, large-water-depth and large-section marine cables. However, the ladder-shaped line conductor has a self-locking structure unlike an SZ-shaped conductor, and if the monofilament is unreasonably designed, a series of problems such as monofilament turning over, difficult stranding and forming, unqualified resistance, low compression coefficient and the like are easily caused. Therefore, how to ensure the reasonability of the design of the ladder-shaped line water-blocking conductor is the premise and key for improving the water-blocking performance of the marine cable product, saving energy and lowering cost.
The existing ladder-type line structure design method mainly comprises a software drawing method and an analytic method, wherein the software drawing method adopts AutoCAD, CAXA and other software to design ladder-type line conductors, and the method is visual, but because each conductor structure needs drawing design and optimization, the method is time-consuming and low in efficiency; the analysis rule is to design the monofilament and conductor structure by using a formula and empirical coefficients, so that the required structure parameters can be obtained quickly, and the design efficiency is improved. At present, most of the conventional ladder-type line conductor patents propose a specific conductor structure type, and no serial design methods are formed, and the ladder-type line conductor design patents do not basically consider the influence of the water-blocking material on the conductor size, are not necessarily suitable for the manufacture of the conductor structure of the marine cable, and the rationality of the design is not yet questioned.
In summary, how to effectively solve the problems of difficult design of structural parameters of the molded-line water-blocking conductor and poor forming effect of the manufacturing process is a problem that needs to be solved urgently by those skilled in the art at present.
Disclosure of Invention
In view of the above, an object of the present invention is to provide a method for designing a molded line water-blocking conductor, which can effectively solve the problems of difficult design of structural parameters of the molded line water-blocking conductor and poor molding effect of the manufacturing process.
In order to achieve the purpose, the invention provides the following technical scheme:
a method for designing a molded line water-blocking conductor comprises the following steps:
step 100: according to conductor filament resistivity ρ20Conductor DC resistance R20Obtaining the cross-sectional area S of the conductorth(ii) a Step 200: according to the cross-sectional area S of the conductorthThe number N of the trapezoidal monofilaments is used for obtaining the section area S of the single trapezoidal monofilament;
step 300: correspondingly obtaining the included angle of the single trapezoidal monofilament of each layer according to the number n of the trapezoidal monofilaments of each layer
Step 400: according to the diameter d of the central cylindrical conductor0The area S of a single trapezoid monofilament, the included angle theta of each trapezoid monofilament, and the set arc chamfer radius r of the inner corner and the outer corner1、r2Obtain eachThe radius R of the inner arc edge and the outer arc edge of the ladder-shaped monofilament is single1、R2And in the two adjacent layers of the trapezoidal monofilaments, the radius of the outer arc edge of the inner layer of the trapezoidal monofilament is equal to that of the inner arc edge of the outer layer of the trapezoidal monofilament, and the radius of the inner arc edge of the innermost layer of the trapezoidal monofilament in each layer of the trapezoidal monofilaments is equal to the diameter d of the central cylindrical conductor0Equal;
step 500: according to the diameter D of the middle and outer arc edges of the ladder-shaped monofilaments positioned at the outermost layer in each layer of ladder-shaped monofilamentscAnd the cross-sectional area S of the conductorthCalculating a current conductor compression coefficient η ', judging whether the current conductor compression coefficient η ' meets the requirement of a preset conductor compression coefficient η, if so, executing the next step, and if not, adjusting related parameters according to the deviation of the current conductor compression coefficient η ' relative to the preset conductor compression coefficient η, and returning to the step to recalculate parameters corresponding to the related parameters;
step 600: according to the radius R of the inner arc edge and the outer arc edge of each layer of the trapezoidal monofilament1、R2And obtaining the width-diameter ratio of each layer of trapezoidal monofilaments according to the included angle theta of the trapezoidal monofilaments, judging whether the width-diameter ratio meets a preset value, if not, adjusting related parameters and returning to the step to recalculate the corresponding parameters.
In the method for designing the molded water-blocking conductor, a series of calculation steps are set, and the resistivity rho of conductor monofilaments is calculated20Conductor DC resistance R20The number of the twisted layers of the trapezoidal monofilaments is m, the number of the trapezoidal monofilaments of each layer is N, the number of the trapezoidal monofilaments is N, and the diameter d of the central cylindrical conductor0Radius r of arc chamfer of inner and outer corner1、r2Setting the parameters as known parameters, and calculating the radius R of the inner and outer arc edges of the trapezoidal monofilament under the condition of meeting the setting requirement1、R2The current conductor compression coefficient η 'and the aspect ratio and other parameters, checking whether the current conductor compression coefficient η' and the aspect ratio and the like meet the requirements, and correspondingly adjusting the known parameters when the current conductor compression coefficient η 'and the aspect ratio and the like do not meet the requirements until the current conductor compression coefficient η' and the aspect ratio meet the requirements, thereby completing the whole molded lineAnd designing parameters of the water blocking conductor. By designing the design method of the molded line water-blocking conductor, specific parameters of the molded line water-blocking conductor can be rapidly acquired. In conclusion, the method for designing the molded line water-blocking conductor can effectively solve the problem that the structural parameters of the molded line water-blocking conductor are difficult to design, and ensures the molding effect of the manufacturing process.
Preferably, the step 100 is: calculating the cross-sectional area of the conductorWherein k is1For conductor form factor, k2Is the conductor strand elongation coefficient, k3The influence coefficient of the resistivity of the twisted conductor is shown.
Preferably, the step 200 is: if the central cylindrical conductor is a round monofilament conductor and the cross-sectional area of the single trapezoidal monofilament is equal to that of the single trapezoidal monofilament, the cross-sectional area of the single trapezoidal monofilament
Preferably, the step 400 comprises the steps of:
step 410: the radius R of the inner arc edge of the trapezoidal monofilament of each layer1The outer arc edge radius R of the ladder-shaped monofilament of the adjacent inner layer2Equal and inner arc edge radius R in the ladder-shaped monofilament of the innermost layer of the conductor1Diameter d of the central cylindrical conductor0Equal;
step 420: according to the corresponding layers obtained from inside to outside in sequence, the radius R of the inner arc edge in the trapezoidal monofilament1Sequentially calculating the radius R of the outer arc edge of each layer of the trapezoidal monofilament from inside to outside through the following formula2：
Wherein, α1、α2Respectively forming included angles S between the extension line of the side edge of the trapezoidal monofilament and the connecting lines between the circle centers of the inner and outer circular arc chamfers and the circle center of the conductorin、SouRespectively the sector areas S corresponding to the inner and outer arc edges of the trapezoidal monofilament formed by the included angle theta1Removing area for inner corner arc chamfering, S2The area of the arc chamfer of the outer corner is removed.
Preferably, the step 500 comprises the steps of:
step 510: calculating the current conductor compression coefficient:
wherein k is4The reduction coefficient of the thickness of the water-blocking material between each layer in the process of twisting the molded line, DiThe diameter of the outer arc edge of each layer of the trapezoidal monofilament is shown, m is the number of layers of the trapezoidal monofilament, and t is the thickness of a water-blocking material;
step 520, judging the current conductor compression coefficient η ' and the preset conductor compression coefficient η, if η ' is not less than η, executing the next step, and if η ' is less than η, increasing the conductor molding coefficient k1The coefficient of elongation of the conductor strand k2Or the coefficient of influence k of the strand resistivity of the conductor3To increase the cross-sectional area S of the conductorthOr increasing the thickness t of the water blocking material and then returning to the step 100.
Preferably, the step 600 comprises the steps of:
step 610: calculating the radial length T ═ R of the trapezoidal monofilament2-R1The outer width of the ladder-shaped monofilamentCalculating the width-diameter ratio W/T;
step 610: and judging whether the width-diameter ratio meets a preset value, if not, adjusting the number n of the trapezoidal monofilaments in a single layer or the number m of the trapezoidal monofilaments, and returning to the step 300.
Preferably, the pitch ratio of the twisted ladder-shaped monofilaments at the inner layer is larger than that of the ladder-shaped monofilaments at the outer layer.
Preferably, the pitch-diameter ratio of the ladder-shaped monofilaments on the innermost layer is 16-20, and the pitch-diameter ratio of the ladder-shaped monofilaments on the outermost layer is 10-14.
Preferably, the central cylindrical conductor is a circular monofilament conductor having a diameter
Preferably, the variation t of the diameter of the wire caused by the thickness of the water-blocking material0The molding coefficient k of the conductor is between 0.04 and 0.06 mm1The value range of (A) is 1.02-1.07; coefficient of elongation of stranded conductor k2The value range of (1.01) to (1.03), and the influence coefficient k of the resistivity after the conductor is stranded3The value range of (A) is 1.005-1.02.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a schematic flow chart of a method for designing a molded-line water-blocking conductor according to an embodiment of the present invention;
FIG. 2 is a schematic cross-sectional view of a single ladder-type monofilament provided in accordance with an embodiment of the present invention;
fig. 3 is a schematic cross-sectional structure view of a molded-line water-blocking conductor according to an embodiment of the present invention.
Detailed Description
The embodiment of the invention discloses a method for designing a molded line water-blocking conductor, which aims to effectively solve the problem that the specific parameters of the molded line water-blocking conductor are difficult to design.
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1 to fig. 3, fig. 1 is a schematic flow chart illustrating a method for designing a molded-line water-blocking conductor according to an embodiment of the present invention; FIG. 2 is a schematic cross-sectional view of a single ladder-type monofilament provided in accordance with an embodiment of the present invention; fig. 3 is a schematic cross-sectional structure view of a molded-line water-blocking conductor according to an embodiment of the present invention.
In this embodiment, a method for designing a wire-type water-blocking conductor is provided. The central line of the molded water-blocking conductor, namely the central cylindrical conductor, can be a single round monofilament or a structure with the center pressing the round conductor, the small-section central cylindrical conductor can adopt the single round monofilament, and the large-section central cylindrical conductor can adopt the center pressing the round water-blocking conductor.
Each layer of the outer surface is formed by twisting trapezoidal monofilaments, wherein the trapezoidal monofilaments refer to conductor monofilaments with trapezoidal cross sections, the conductor monofilaments are mainly sector-shaped, namely the upper bottom edge and the lower bottom edge are inner arc edges and outer arc edges which are coaxially arranged, waist edges on two sides are radial line segments corresponding to the axes, four corners are generally arranged in a chamfer mode, chamfers of two inner corner portions are equal, and chamfers of two outer corner portions are equal.
The ladder-shaped monofilaments on the same layer have the same shape and size, the ladder-shaped monofilaments on different layers have the same cross-sectional area, and water-blocking materials such as water-blocking tapes or other water-blocking compounds are filled between the ladder-shaped monofilaments on adjacent layers. The inner part and the outer part of the trapezoidal line are of circular arc structures so that the inner part and the outer part of the trapezoidal monofilament are tightly attached to the adjacent twisted layers; four angles of ladder type line are circular arc chamfer, prevent ladder type monofilament threading and transposition in-process edge from producing and scraping.
The specific method for designing the molded water-blocking conductor comprises the following steps which are not strictly required to be executed in sequence.
Step 100: according to conductor filament resistivity ρ20Conductor DC resistance R20Obtaining the cross-sectional area S of the conductorth。
Wherein the cross-sectional area S of the conductorthThe cross-sectional area of the whole molded line water-blocking conductor is the sum of the cross-sectional area of the central cylindrical conductor and the cross-sectional area of each trapezoidal monofilament. The theoretical minimum sectional area of the molded water-blocking conductor is calculated mainly according to the maximum direct current resistance value required in the conductor standard, and meanwhile, the influence of various factors such as water-blocking materials, twisting modes, conductor diameters, the number of cable cores, extension coefficients and trapezoidal monofilament resistivity after forming on the conductor structure in the actual production process is preferably further considered, so that the designed conductor sectional area SthThe cross section of the conductor produced can be better ensured to meet the resistance requirement without being smaller than the theoretical minimum cross section.
Specifically, the conductor cross-sectional area is preferably calculated here according to the following formula (1):
wherein k is1For conductor form factor, k2Is the conductor strand elongation coefficient, k3The influence coefficient of the stranded electrical resistivity of the conductor is shown. In the formula, SthThe cross-sectional area is designed for a conductor that meets resistance requirements, and is typically in square millimeters (mm)2)；ρ20The resistivity of the ladder-shaped monofilament at 20 ℃ is omega mm2M (ohms by square millimeters per meter); r20The maximum direct current resistance of the conductor at 20 ℃ can be obtained according to Chinese standard GB/T3956, and the unit is generally omega/m (ohm per meter); k is a radical of1The forming coefficient of the conductor is the introduction coefficient related to the thickness, the twisting mode, the number of formed cable cores and the like of the water-blocking material, and the preferable value range is 1.02-1.07; k is a radical of2The elongation coefficient of the conductor is small because the sectional area is not greatly changed after the molded line structure is twisted, and the preferred value range is 1.01-1.03; k is a radical of3Conductor resistivity, i.e. after twisting of the filamentsThe preferable value range of the introduction coefficient of the increase of the resistivity of the metal wire is 1.005-1.02.
Step 200: according to the cross-sectional area S of the conductorthAnd the number N of the trapezoidal monofilaments is used for obtaining the section area S of the single trapezoidal monofilament.
The total trapezoidal monofilament number N, the number m of trapezoidal monofilament layers and the trapezoidal monofilament number N of each layer of the molded line water-blocking conductor are mainly set according to needs, and generally need to meet the currently required industrial standard requirements, such as the requirement of the minimum monofilament number in the Chinese standard GB/T3956 and the maximum production capacity of actual equipment. According to the production capacity of the existing cable conductor stranding equipment, 1-6 layers can be taken out.
As mentioned above, the central cylindrical conductor may be a single round monofilament, or may be a conductor with a center pressed tightly against the round conductor. If the conductor is a round monofilament conductor, the cross-sectional area of the round monofilament conductor is generally equal to the cross-sectional area of the single trapezoidal monofilament, for example, if the conductor is a center compacted round conductor, the cross-sectional area S of the center compacted round conductor is obtained according to the size of the center compacted round conductorcir。
Based on this, it is preferable here that the step 200 is specifically: if the central cylindrical conductor is a single filament and the cross-sectional area of the central cylindrical conductor is equal to the cross-sectional area of the single trapezoidal filament, calculating the cross-sectional area S of the single trapezoidal filament according to the following formula (2):
if the central cylindrical conductor is a central compact round conductor, calculating the section area S of the single trapezoidal monofilament according to the following formula (3):
wherein ScirThe cross-sectional area of the central circular compacted conductor is typically measured in square millimeters.
In the above formulas (2) and (3), S is the equivalent average cross-sectional area of a single ladder-shaped wire and has a unit ofSquare millimeter; n is the total number of the ladder-shaped monofilaments and does not contain a central line structure, wherein SthI.e. the cross-sectional area of the conductor calculated above.
Step 300: correspondingly obtaining the included angle theta of the single trapezoidal monofilament of each layer according to the number n of the trapezoidal monofilaments of each layer, wherein the included angle theta of the single trapezoidal monofilament is calculated according to the following formula (4):
wherein the included angle theta of the single trapezoidal monofilament is degree. As described above, the trapezoidal monofilaments of each layer have the same cross section, size and shape, so that n trapezoidal monofilaments of one layer are closely connected to enclose a circumference, and thus, for each trapezoidal monofilament of a certain layer, the included angle is equal to n equal parts of a circumference angle. It should be noted that, since the number of the ladder-shaped monofilaments of each layer may be different, the included angle of the ladder-shaped monofilaments of each layer should be calculated correspondingly.
Step 400: according to the diameter d of the central cylindrical conductor0The area S of a single trapezoid monofilament, the included angle theta of each layer of the single trapezoid monofilament, and the set radius r of the arc chamfer of the inner corner and the outer corner1、r2Obtaining the radius R of the inner arc edge and the outer arc edge of each layer of the trapezoidal monofilament1、R2And in the two adjacent layers of the trapezoidal monofilaments, the radius of the outer arc edge of the inner layer of the trapezoidal monofilament is equal to that of the inner arc edge of the outer layer of the trapezoidal monofilament, and the radius of the inner arc edge of the innermost layer of the trapezoidal monofilament in each layer of the trapezoidal monofilaments is equal to the diameter d of the central cylindrical conductor0Are equal.
It is noted that, among them, the diameter d of the central cylindrical conductor0The diameter d of the central cylindrical conductor can be directly obtained from the arranged central compact round conductor if the central cylindrical conductor is a round monofilament conductor or the central compact round conductor is considered in general0In the case of a round monofilament conductor, the round monofilament conductor can be calculated by the following formula (5):
wherein S is the calculated trapezoidal monofilament section area S, t0The range of the value of the small variation of the diameter of the metal wire caused by the thickness of the water-blocking material is 0.04-0.06 mm according to production experience.
Wherein the radius r of the arc chamfer of the inner corner and the outer corner of the trapezoidal monofilament1、r2And the value range is 0.2-0.8 mm, wherein the radiuses of the circular arc chamfers of the two inner corners are equal, and the radiuses of the circular arc chamfers of the two outer corners are equal. Because the length of the inner arc of the trapezoidal monofilament is less than that of the outer arc, the radius r of the arc chamfer of the inner corner of the trapezoidal monofilament1≤r2。
It should be noted that the radius R of the inner arc edge of the trapezoidal monofilament1The radius R of the outer arc edge of the ladder-shaped monofilament on the upper layer is considered2Equal to each other, and the radius of the inner arc edge of the ladder-shaped monofilament at the innermost layer in each layer of ladder-shaped monofilaments is equal to the diameter d of the central cylindrical conductor0Are equal. E.g. by the diameter d of the central cylindrical conductor0The diameter of the inner arc edge of the first layer of trapezoidal monofilaments is equal, and the radius R of the outer arc edge of the first layer of trapezoidal monofilaments can be further calculated2(ii) a The radius of the inner arc edge of the second layer of ladder-shaped monofilaments is the same as that of the outer arc edge of the first layer of ladder-shaped monofilaments, so that the radius of the outer arc of the second layer of ladder-shaped monofilaments can be obtained, and the radius of the inner arc and the radius of the outer arc of each layer of ladder-shaped monofilaments can be obtained in sequence.
Therefore, the step 400 preferably includes the following steps:
step 410: the radius R of the inner arc edge of the trapezoidal monofilament of each layer1The outer arc edge radius R of the ladder-shaped monofilament of the adjacent inner layer2Equal and inner arc edge radius R in the ladder-shaped monofilament of the innermost layer of the conductor1Diameter d of the central cylindrical conductor0Equal;
step 420: according to the corresponding layers obtained from inside to outside in sequence, the radius R of the inner arc edge in the trapezoidal monofilament1Sequentially calculating the radius R of the outer arc edge of each layer of the trapezoidal monofilament from inside to outside through the following formula (6)2：
Wherein, α1、α2The included angles are respectively formed by connecting lines between the extension line of the side edge of the trapezoidal monofilament, the circle centers of the inner and outer circular arc chamfers and the circle center of the conductor, and the unit is generally degree. Sin、SouThe sector areas corresponding to the inner and outer arc sides of the trapezoidal monofilament formed by the included angle theta are respectively, and the unit is generally square millimeter. S1Removing area for the arc chamfer of the inner corner part, namely subtracting the residual area of one end of the outer inner side of the sectional area S of the molded line from the area surrounded by the inner arc edge and the outer arc edge of the trapezoidal monofilament in a sector shape; s2The area of the arc chamfer at the outer corner is removed, namely the residual area of one end of the outer side outside the sectional area S of the molded line is subtracted from the area surrounded by the sector of the inner arc edge and the outer arc edge of the trapezoidal monofilament. DiThe outer diameter of the conductor of the stranded layer of the ith ladder-shaped monofilament is equal to the outer arc diameter of the ladder-shaped conductor of the ith ladder-shaped monofilament, and the unit is generally millimeter, wherein the diameter of the outermost layer of the conductor is represented by DcAnd (4) showing.
Step 500: according to the outermost diameter D of the conductorcAnd the cross-sectional area S of the conductorthCalculating a current conductor compression coefficient η ', judging whether the current conductor compression coefficient η ' meets the requirement of a preset conductor compression coefficient η, if so, executing the next step, if not, adjusting related parameters according to the deviation of the current conductor compression coefficient η ' relative to the preset conductor compression coefficient η, and returning to the above steps to recalculate parameters corresponding to the related parameterscI.e. twice the radius of the outer arc edge of the trapezoidal monofilament at the outermost layer.
For the molded line water-blocking conductor, the compression coefficient eta of the preset conductor can be determined according to the water-blocking requirement of the molded line conductor, the higher the compression coefficient is, the better the water-blocking effect of the conductor is, and the compression coefficient eta of the preset conductor can be set to be more than or equal to 0.94 according to the laying environment and the water depth.
Specifically, the preferred step 500 herein comprises the steps of:
step 510: calculating the current conductor compression coefficient:
wherein k is4The thickness reduction coefficient of the water-blocking material between each layer in the twisting process of the molded line depends on the material characteristics, and the semi-conductive water-blocking tape can be between 2 and 4; diThe diameter of the outer arc edge of each layer of the trapezoidal monofilament, m is the number of layers of the trapezoidal monofilament and t is the thickness of a water-blocking material, the thickness of the water-blocking material generally takes a value of 0.2-0.5 mm, wherein d0Diameter of central cylindrical conductor, k1Is the conductor forming coefficient, pi is the circumference ratio, DcIs the outermost diameter of the conductor, SthIs the conductor cross-sectional area.
Step 520, judging the current conductor compression coefficient η ' and the preset conductor compression coefficient η, if η ' is not less than η, executing the next step, and if η ' is less than η, increasing the conductor molding coefficient k1The coefficient of elongation of the conductor strand k2Or the coefficient of influence k of the strand resistivity of the conductor3To increase the cross-sectional area S of the conductorthOr increasing the thickness t of the water blocking material and then returning to the step 100.
It should be noted that, when adjusting the parameters, the corresponding proportion adjustment can be performed according to the difference between η' and η. a better adjustment mode is that the value range of the adjustment parameters can be divided into equal parts, the equal parts can be 5 parts, 10 parts, 100 parts and the like, and the adjustment can be performed by adding one part each time, for example, the conductor twist elongation coefficient k2The value range is 1.01-1.03, the coefficient range can be divided into 20 parts, if the conductor twisting extension coefficient k is2At 1.01, the conductor strand elongation coefficient k may be increased if the current conductor compression coefficient η' is still less than the predetermined conductor compression coefficient η2The value is newly taken to be 1.011 mm, so as to calculate the relevant parameters again, further calculate the current conductor compacting coefficient η', if the current conductor compacting coefficient still does not work, the conductor twisting extension coefficient k needs to be increased again2Until the current conductor compression factor η' meets the design requirements, and the conductor strand elongation coefficient k2When the maximum value is reached, others can be adjustedParameters to increase the current conductor compaction factor η' until no adjustment is possible, at which point the calculation is terminated.
Step 600: according to the radius R of the inner arc edge and the outer arc edge of each layer of the trapezoidal monofilament1、R2And obtaining the width-diameter ratio of each layer of trapezoidal monofilaments according to the included angle theta of the trapezoidal monofilaments, judging whether the width-diameter ratio meets a preset value, if not, adjusting related parameters and returning to the step to recalculate the corresponding parameters.
Wherein the ratio of the width to the diameter is the ratio of the radial length T to the outer width W of the ladder monofilament. Comparing the width ratio W/T of the monofilaments of each layer of the profile line stranding layer, for example, if the W/T is more than or equal to 1.1, determining that the width ratio W/T meets the requirement; if W/T is less than 1.1, the width of the trapezoidal monofilament is short, the turnover phenomenon is easy to occur during twisting, relevant parameters are optimized and adjusted, and then the step is executed again. Based on this, it is preferable that the step 600 includes the steps of:
step 610: calculating the radial length T ═ R of the trapezoidal monofilament2-R1The outer width of the ladder-shaped monofilamentCalculating the width-diameter ratio W/T;
step 620: and judging whether the width-diameter ratio meets a preset value, if not, adjusting the number n of the single-layer trapezoidal monofilaments or the number m of the layers of the trapezoidal monofilaments, and returning to the step 300. Wherein for the adjustment of the number n of the single-layer ladder-type monofilaments, the conductor twisting elongation coefficient k can be adjusted by referring to the adjustment parameter2The method (1). The specific adjustment mode can reduce the number n of the single-layer trapezoidal monofilaments by 1 every time to increase the width of a single trapezoidal monofilament, if the width-diameter ratio W/T of the monofilament still does not meet the requirement, the number m of the trapezoidal monofilaments needs to be increased or decreased to adjust the width-diameter ratio W/T of the monofilament, and the number of layers is increased or decreased to be 1 layer each time. Here, the aspect ratio of each layer should be satisfied.
In the method for designing the molded water-blocking conductor, a series of calculation steps are set, and the resistivity rho of conductor monofilaments is calculated20Conductor DC resistance R20The number of the twisted layers of the trapezoidal monofilaments is m, the number of the trapezoidal monofilaments in each layer is n, and the trapezoidal shapeNumber of filaments N, diameter d of central cylindrical conductor0Radius r of arc chamfer of inner and outer corner1、r2Setting the parameters as known parameters, and calculating the radius R of the inner and outer arc edges of the trapezoidal monofilament under the condition of meeting the setting requirement1、R2The method comprises the steps of checking and calculating parameters such as a current conductor compression coefficient η ' and an aspect ratio, checking and calculating whether the current conductor compression coefficient η ' and the aspect ratio meet requirements, and correspondingly adjusting known parameters when the current conductor compression coefficient η ' and the aspect ratio do not meet the requirements, so that parameter design of the whole molded line water-blocking conductor is completed.
Further, it is preferable that the pitch ratio of the ladder-shaped monofilament in the inner layer is larger than that of the ladder-shaped monofilament in the outer layer. Specifically, the pitch-diameter ratio of the ladder-shaped monofilaments at the innermost layer generally ranges from 16 to 20, the pitch-diameter ratio of the ladder-shaped monofilaments at the outermost layer generally ranges from 10 to 14, and the pitch-diameter ratio of the ladder-shaped monofilaments at the middle layer gradually decreases from inside to outside within the range between the inner layer and the outer layer. It should be noted that, the pitch-diameter ratio refers to the ratio of the pitch length to the outer diameter of the stranded wire, any single wire in each layer of the stranded wire is spirally stranded around a center line at a certain stranding angle, and a complete spiral pitch in the axial direction of the stranded wire is the pitch length.
In another embodiment, 400mm is provided2The (square millimeter) copper core type line water-blocking conductor design method comprises the following specific design steps:
step 101: according to conductor filament resistivity ρ20Conductor DC resistance R20Obtaining the cross-sectional area S of the conductorth：
In the formula, resistivity rho of copper monofilament2The value is 0.0171 omega mm2(ii)/m; conductor maximum direct current resistance R at 20 DEG C20A value of 4.7 × 10-5Ω/m；k1Taking the molding coefficient of the conductor as 1.05; k is a radical of2Taking the stranding elongation coefficient of the conductor as 1.01; k is a radical of3The influence coefficient of the stranded resistivity of the conductor is 1.01.
Calculating according to a formula to obtain Sth＝389.3mm2(square millimeter).
Step 201: according to the cross-sectional area S of the conductorthAnd the number N of the trapezoidal monofilaments is used for obtaining the section area S of the single trapezoidal monofilament.
The copper core type wire water-blocking conductor can be preset specifically: the three-phase alternating current power supply comprises 1 circular monofilament conductor located in the center, 6 trapezoidal monofilaments on the first layer, 12 trapezoidal monofilaments on the second layer, 18 trapezoidal monofilaments on the third layer and 23 trapezoidal monofilaments on the fourth layer, wherein the number m of the trapezoidal monofilaments is equal to 4, and the number N of the trapezoidal monofilaments in the whole is equal to 59.
Then the cross-sectional area S of a single said ladder-shaped monofilament is calculated according to the following formula:
Step 301: calculating included angle of single trapezoidal monofilament in each layerBecause from inside to outside, n is: 6. 12, 18 and 23, corresponding to the included angles theta of the single trapezoidal monofilaments in the layers from inside to outside of 60 degrees, 30 degrees, 20 degrees and 15.65 degrees.
Step 411: calculating the diameter of a round monofilament conductort0The diameter of the metal wire is 0.05mm, which is the small variation caused by the thickness of the water-blocking material. Calculating the diameter d of the round monofilament conductor0＝2.82mm。
Step 421: sequentially calculating the radius R of the outer arc edge of each layer of the trapezoidal monofilament from inside to outside through the following formula2
Wherein the radius r of the arc chamfer of the inner corner and the outer corner of the trapezoidal monofilament1、r2All are 0.3 mm. Then obtaining the diameter d of the central cylindrical conductor according to the above02.82mm, and 6.49mm2The included angle theta of the single trapezoidal monofilament of each layer is 60 degrees, 30 degrees, 20 degrees and 15.65 degrees, and the radius R of the inner arc edge and the outer arc edge of the single trapezoidal monofilament of each layer is obtained through calculation1、R2The specific data are shown in Table 1.
Step 511: the current conductor compaction factor is calculated according to the following formula:
wherein k is4A semiconductive water-blocking tape k for reducing the thickness coefficient of the water-blocking material between each layer in the twisting process of the molded line4T is the thickness of the water-blocking material, 0.3mm is taken, and the current conductor compression coefficient η' is calculated to be 0.974.
Step 521: and comparing the current conductor compression coefficient eta 'with a preset conductor compression coefficient eta, wherein the molded line conductor compression coefficient eta is set according to the laying environment and the water depth, and the eta is 0.96, so that the eta is less than or equal to eta', and the designed molded line conductor is reasonable in structure.
Step 601: according to the formula
According to the calculation result, 400mm is obtained2The design parameters of the copper core type wire water-blocking conductor (in square millimeters) are shown in table 1.
Table 1: 400mm2(square mm) parameters of copper core type wire water-blocking conductorWatch (A)
In another embodiment, according to the above calculation method, 2000mm can be obtained correspondingly2The parameters of the aluminum core type wire water-blocking conductor are shown in the table 2.
Table 2: 2000mm2(square mm) aluminium core type wire water-blocking conductor parameter table
Through the above embodiments, it can be found that the beneficial effects of the present embodiment are mainly as follows:
firstly, the water-blocking type wire conductor designed by the method is of a uniform-section full-profile wire structure, the outer diameter of the water-blocking type wire conductor is 0.5-2.5 mm smaller than that of a round compressed conductor, the large-section conductor is optimized more remarkably, the weight of the submarine cable can be effectively reduced, and the whole material consumption and the manufacturing cost of the submarine cable are reduced.
Secondly, the compression coefficient of the water-blocking type wire conductor designed by the method can reach 0.94-0.98, the circular compressed conductor structure can only reach 0.88-0.92, the water-blocking performance of the wire structure is obvious, the layers of the conductor are tightly attached, and the method is suitable for designing conductor structures of deep ocean cables in the deep water of 3000m (meters) and below.
Thirdly, the water-blocking type wire conductor designed by adopting the method considers the influence of the thickness of the water-blocking material, and compared with other methods for designing the wire conductor, the design structure is more reasonable, and the method is effective and reliable for designing water-blocking type cables and submarine cables.
Fourthly, the molded line water-blocking conductor design method adopts a mode of combining an analytic method, a geometric method and an empirical method, has complete design flow, strong universality and high programmability, is more efficient than a drawing method in design, can adjust design coefficients according to actual process debugging result feedback, has the characteristic of flexible self-optimization, and can be suitable for 50-3500 mm2(square millimeter) various ladder-type wire water-blocking conductor structure designs.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.