CN110774565A - Extrusion method of cable hollow supporting structure - Google Patents

Extrusion method of cable hollow supporting structure Download PDF

Info

Publication number
CN110774565A
CN110774565A CN201911228550.8A CN201911228550A CN110774565A CN 110774565 A CN110774565 A CN 110774565A CN 201911228550 A CN201911228550 A CN 201911228550A CN 110774565 A CN110774565 A CN 110774565A
Authority
CN
China
Prior art keywords
die
mold
rear part
sleeve
air outlet
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201911228550.8A
Other languages
Chinese (zh)
Inventor
张广柱
王雪松
祝军
李斌
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Jiangsu Shangshang Cable Group Co Ltd
Original Assignee
Jiangsu Shangshang Cable Group Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Jiangsu Shangshang Cable Group Co Ltd filed Critical Jiangsu Shangshang Cable Group Co Ltd
Priority to CN201911228550.8A priority Critical patent/CN110774565A/en
Publication of CN110774565A publication Critical patent/CN110774565A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/30—Extrusion nozzles or dies
    • B29C48/32—Extrusion nozzles or dies with annular openings, e.g. for forming tubular articles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/15—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor incorporating preformed parts or layers, e.g. extrusion moulding around inserts
    • B29C48/154—Coating solid articles, i.e. non-hollow articles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/92—Measuring, controlling or regulating
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B13/00—Apparatus or processes specially adapted for manufacturing conductors or cables
    • H01B13/0016—Apparatus or processes specially adapted for manufacturing conductors or cables for heat treatment
    • H01B13/002—Apparatus or processes specially adapted for manufacturing conductors or cables for heat treatment for heat extraction
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B13/00—Apparatus or processes specially adapted for manufacturing conductors or cables
    • H01B13/06—Insulating conductors or cables
    • H01B13/14—Insulating conductors or cables by extrusion
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B13/00—Apparatus or processes specially adapted for manufacturing conductors or cables
    • H01B13/22—Sheathing; Armouring; Screening; Applying other protective layers
    • H01B13/24—Sheathing; Armouring; Screening; Applying other protective layers by extrusion

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Extrusion Moulding Of Plastics Or The Like (AREA)

Abstract

An extrusion method of a cable hollow supporting structure comprises the steps of firstly installing an extrusion die assembly in an extruding machine; and then the cable is extruded with a hollow supporting structure. The extrusion die assembly comprises a die core, a die sleeve combining cap, a middle die and a middle die pressing ring; the rear part of the mold core is arranged in the truncated cone-shaped cavity at the front part of the mold sleeve, and a sizing material runner is reserved between the outer wall of the rear part of the mold core and the truncated cone-shaped cavity; the front part of the die is in a cylindrical shape, and the radial section of the middle part of the middle die is in a circular ring shape; the rear part of the middle mold is formed by a plurality of air outlet separation columns surrounding the wiring channel; the middle die sleeve is sleeved in a cylindrical cavity at the rear part of the die sleeve, and a sizing material runner is reserved between the middle die sleeve and the air outlet separation column; the air outlet separation column is parallel to the wiring channel; a through bronchus is arranged in the air outlet separation column, an air outlet of the bronchus faces the rear part of the air outlet separation column, an air inlet of the bronchus is connected with an annular main air pipe, an air inlet hole is formed in the middle of the middle mold, and the air inlet hole is connected with the main air pipe; an air inlet pipe hermetically connected with the air inlet hole is arranged on the side wall of the rear part of the die sleeve corresponding to the air inlet hole.

Description

Extrusion method of cable hollow supporting structure
Technical Field
The invention relates to the technical field of cable production, in particular to an extrusion method of a cable hollow supporting structure.
Background
In the prior art, for the reasons of conductor cooling, and the like, some special cables are provided with a hollow support structure outside the conductor, and then other functional layers outside the support structure. The cooling medium is introduced through the tubular through hole formed by the supporting structure, and the conductor is directly cooled in the cable. Most of cable production is continuous production of a production line, and the problem to be solved is how to bring the production of the support structure with the through hole into the production line and ensure the smoothness and uniformity in the tubular through hole.
Disclosure of Invention
The invention provides an extrusion method of a cable hollow supporting structure and an extrusion die assembly of the cable hollow supporting structure aiming at the problems in the prior art, and the extrusion method specifically comprises the following steps:
a method of extruding a hollow cable support structure, the steps comprising: 1) installing an extrusion die assembly on the plastic extruding machine; 2) according to the extrusion process, the hollow supporting structure is extruded outside the cable, and the method is characterized in that
In the step 1): the extrusion die assembly comprises a die core, a die sleeve combining cap, a middle die and a middle die pressing ring; the center positions of the mold core, the mold sleeve combining cap, the middle mold and the middle mold connecting mechanism are provided with wiring channels for cables to pass through, the wire inlet ends of the wiring channels are arranged in front, and the wire outlet ends are arranged in back;
the shape of the rear part of the mold core is a circular truncated cone shape, and the smaller bottom of the circular truncated cone faces the rear end; the front part of the mold core is provided with a structure connected with the extruder body;
the shape of the front part of the die sleeve is cylindrical, a truncated cone-shaped cavity is formed in the front part of the die sleeve, and the shape of the truncated cone-shaped cavity corresponds to the shape of the rear part of the die core; the rear part of the die sleeve is cylindrical, and a cylindrical cavity is formed in the rear part of the die sleeve; the outer diameter of the rear part of the die sleeve is smaller than that of the front part of the die sleeve;
the radial section of the die sleeve and the die cap is in a ring shape, the inner diameter of the ring corresponds to the outer diameter of the rear part of the die sleeve, and the outer diameter of the ring is larger than the outer diameter of the front part of the die sleeve; the outer wall of the mold sleeve and the outer wall of the mold cap are provided with threads connected with the extruder body;
the rear part of the mold core is arranged in the truncated cone-shaped cavity at the front part of the mold sleeve, and a sizing material runner is reserved between the outer wall of the rear part of the mold core and the truncated cone-shaped cavity; the die sleeve and the cap are sleeved outside the rear part of the die sleeve;
the middle mold consists of a front part, a middle part and a rear part which are connected with each other; the front part of the middle die is in a cylindrical shape, and the radial section of the middle part of the middle die is in a circular ring shape; the outer diameter of the middle part of the middle die is larger than that of the front part of the middle die;
the rear part of the middle mold is formed by a plurality of air outlet separation columns surrounding the wiring channel; the outer diameter of the outer wall of each air outlet separation column which is encircled into a cylindrical shape is smaller than the outer diameter of the middle part of the middle mold;
the middle mold is sleeved in a cylindrical cavity at the rear part of the mold sleeve, the middle mold sleeve is sleeved outside the air outlet spacer, and a sizing material flow channel is reserved between the middle mold sleeve and the air outlet spacer;
the middle die pressing ring presses the middle die sleeve and the middle die from back to front, and the outer wall of the middle die pressing ring is connected with the inner wall of the rear part of the die sleeve through threads;
the shape of the air outlet separation column corresponds to the shape of the inner cavity of the tubular through hole of the processed support structure; the number and the positions of the air outlet separation columns correspond to the number and the positions of the tubular through holes of the processed support structure; the air outlet separation column is parallel to the wiring channel; a through bronchus is arranged in the air outlet partition column, an air outlet of the bronchus faces the rear part of the air outlet partition column, an air inlet of the bronchus is connected with an annular main air pipe, the main air pipe is embedded in the middle part of the middle mold, and an air inlet hole is formed in the middle part of the middle mold and connected with the main air pipe;
an air inlet pipe is arranged on the side wall of the rear part of the die sleeve, which corresponds to the air inlet hole, and the air inlet pipe is hermetically connected with the air inlet hole;
in the step 2): the aperture of the mold core is larger than the diameter of the wire core; the machine body and the machine head are heated by adopting a thermocouple, and the temperature of each temperature zone is set according to the extrusion material; and applying circulating cooling air to the air inlet during extrusion, wherein the air pressure is set to be 0.5-1 MPa.
Further, in the step 1), the front end of an inner cavity at the front part of the middle die of the extrusion die assembly is in a circular truncated cone shape; the rear end of the rear part of the mold core is arranged in the front end of the inner cavity of the front part of the middle mold, and a sizing material flow passage is reserved between the rear end of the mold core and the inner cavity of the front part of the middle mold.
In the step 2), the aperture of the mold core is equal to the diameter of the wire core plus 0.3 mm.
An extrusion die assembly of a cable hollow supporting structure comprises a die core, a die sleeve combining cap, a middle die and a middle die pressing ring; the center positions of the mold core, the mold sleeve combining cap, the middle mold and the middle mold connecting mechanism are provided with wiring channels for cables to pass through, the wire inlet ends of the wiring channels are arranged in front, and the wire outlet ends are arranged in back;
the shape of the rear part of the mold core is a circular truncated cone shape, and the smaller bottom of the circular truncated cone faces the rear end; the front part of the mold core is provided with a structure connected with the extruder body;
the shape of the front part of the die sleeve is cylindrical, a truncated cone-shaped cavity is formed in the front part of the die sleeve, and the shape of the truncated cone-shaped cavity corresponds to the shape of the rear part of the die core; the rear part of the die sleeve is cylindrical, and a cylindrical cavity is formed in the rear part of the die sleeve; the outer diameter of the rear part of the die sleeve is smaller than that of the front part of the die sleeve;
the radial section of the die sleeve and the die cap is in a ring shape, the inner diameter of the ring corresponds to the outer diameter of the rear part of the die sleeve, and the outer diameter of the ring is larger than the outer diameter of the front part of the die sleeve; the outer wall of the mold sleeve and the outer wall of the mold cap are provided with threads connected with the extruder body;
the rear part of the mold core is arranged in the truncated cone-shaped cavity at the front part of the mold sleeve, and a sizing material runner is reserved between the outer wall of the rear part of the mold core and the truncated cone-shaped cavity; the die sleeve and the cap are sleeved outside the rear part of the die sleeve;
the middle mold consists of a front part, a middle part and a rear part which are connected with each other; the front part of the middle die is in a cylindrical shape, and the radial section of the middle part of the middle die is in a circular ring shape; the outer diameter of the middle part of the middle die is larger than that of the front part of the middle die;
the rear part of the middle mold is formed by a plurality of air outlet separation columns surrounding the wiring channel; the outer diameter of the outer wall of each air outlet separation column which is encircled into a cylindrical shape is smaller than the outer diameter of the middle part of the middle mold;
the middle mold is sleeved in a cylindrical cavity at the rear part of the mold sleeve, the middle mold sleeve is sleeved outside the air outlet spacer, and a sizing material flow channel is reserved between the middle mold sleeve and the air outlet spacer;
the middle die pressing ring presses the middle die sleeve and the middle die from back to front, and the outer wall of the middle die pressing ring is connected with the inner wall of the rear part of the die sleeve through threads;
the shape of the air outlet separation column corresponds to the shape of the inner cavity of the tubular through hole of the processed support structure; the number and the positions of the air outlet separation columns correspond to the number and the positions of the tubular through holes of the processed support structure; the air outlet separation column is parallel to the wiring channel; a through bronchus is arranged in the air outlet partition column, an air outlet of the bronchus faces the rear part of the air outlet partition column, an air inlet of the bronchus is connected with an annular main air pipe, the main air pipe is embedded in the middle part of the middle mold, and an air inlet hole is formed in the middle part of the middle mold and connected with the main air pipe;
an air inlet pipe is arranged on the side wall of the rear part of the die sleeve corresponding to the air inlet hole, and the air inlet pipe is hermetically connected with the air inlet hole.
Furthermore, the front end of the inner cavity at the front part of the middle die is in a round table shape; the rear end of the rear part of the mold core is arranged in the front end of the inner cavity of the front part of the middle mold, and a sizing material flow passage is reserved between the rear end of the mold core and the inner cavity of the front part of the middle mold.
Compared with the prior art, the invention has the following beneficial effects: the production of the supporting structure with the through holes is integrated into a production line, and the smoothness and the uniformity in the tubular through holes can be ensured.
Drawings
Fig. 1 is a schematic view (axial section) of the present mold assembly in use.
FIG. 2 is a left direction of the middle mold (viewing angle from the rear end of the line channel);
FIG. 3 is a schematic view (axial section) of a middle mold;
FIG. 4 is a schematic view of the outer shape of the middle mold;
FIG. 5 is a first schematic view in radial cross-section of a hollow support structure for cables machined from the mold assembly of the present example;
FIG. 6 is a second schematic view in radial cross-section of the hollow support structure for cables machined from the mold assembly of the present example, with the cables in the support structure shown in phantom;
FIG. 7 is a dimension identification diagram of a die in this example;
wherein: the mold comprises a mold core 1, a mold sleeve 2, a mold sleeve combining cap 3, a middle mold 4, a middle mold pressing ring 5, a routing channel 6, a glue material flow channel 7, an air outlet separation column 8, a middle mold sleeve 9, a branch air pipe 10, a main air pipe 11, an air inlet hole 12, an air inlet pipe 13, a spiral extrusion shaft 14 of an extruder, a machine body 15 of the extruder, a tubular through hole 16 of a supporting structure, an air outlet hole 17 of the branch air pipe, a supporting body 18 and an outer insulating layer 19.
Detailed Description
The invention is described in further detail below with reference to the figures and the examples of embodiment.
A method of extruding a hollow cable support structure, the steps comprising: 1) installing an extrusion die assembly on the plastic extruding machine; 2) according to the extrusion process, the hollow supporting structure is extruded outside the cable.
The extrusion die assembly of the embodiment shown in FIG. 1 comprises a die core, a die sleeve combining cap, a middle die and a middle die pressing ring; the center positions of the mold core, the mold sleeve combining cap, the middle mold and the middle mold connecting mechanism are provided with wiring channels for cables to pass through, the wire inlet ends of the wiring channels are arranged in front, and the wire outlet ends are arranged in back;
the shape of the rear part of the mold core is a circular truncated cone shape, and the smaller bottom of the circular truncated cone faces the rear end; the front part of the mould core is provided with a structure (in this example, a spiral connecting structure) connected with the extruder body;
the shape of the front part of the die sleeve is cylindrical, a truncated cone-shaped cavity is formed in the front part of the die sleeve, and the shape of the truncated cone-shaped cavity corresponds to the shape of the rear part of the die core; the rear part of the die sleeve is cylindrical, and a cylindrical cavity is formed in the rear part of the die sleeve; the outer diameter of the rear part of the die sleeve is smaller than that of the front part of the die sleeve;
the radial section of the die sleeve and the die cap is in a ring shape, the inner diameter of the ring corresponds to the outer diameter of the rear part of the die sleeve, and the outer diameter of the ring is larger than the outer diameter of the front part of the die sleeve; the outer wall of the mold sleeve and the outer wall of the mold cap are provided with threads connected with the extruder body;
the rear part of the mold core is arranged in the truncated cone-shaped cavity at the front part of the mold sleeve, and a sizing material runner is reserved between the outer wall of the rear part of the mold core and the truncated cone-shaped cavity; the die sleeve and the cap are sleeved outside the rear part of the die sleeve;
as shown in fig. 2-4, the middle mold is composed of a front part, a middle part and a rear part which are connected with each other; the front part of the middle die is in a cylindrical shape, and the radial section of the middle part of the middle die is in a circular ring shape; the outer diameter of the middle part of the middle die is larger than that of the front part of the middle die;
the rear part of the middle mold is formed by a plurality of air outlet separation columns surrounding the wiring channel; the outer diameter of the outer wall of each air outlet separation column which is encircled into a cylindrical shape is smaller than the outer diameter of the middle part of the middle mold;
the middle mold is sleeved in a cylindrical cavity at the rear part of the mold sleeve, the middle mold sleeve is sleeved outside the air outlet spacer, and a sizing material flow channel is reserved between the middle mold sleeve and the air outlet spacer;
the middle die pressing ring presses the middle die sleeve and the middle die from back to front, and the outer wall of the middle die pressing ring is connected with the inner wall of the rear part of the die sleeve through threads;
the shape of the air outlet separation column corresponds to the shape of the inner cavity of the tubular through hole of the processed support structure; the number and the positions of the air outlet separation columns correspond to the number and the positions of the tubular through holes of the processed support structure; the air outlet separation column is parallel to the wiring channel; a through bronchus is arranged in the air outlet partition column, an air outlet of the bronchus faces the rear part of the air outlet partition column, an air inlet of the bronchus is connected with an annular main air pipe, the main air pipe is embedded in the middle part of the middle mold, and an air inlet hole is formed in the middle part of the middle mold and connected with the main air pipe;
an air inlet pipe is arranged on the side wall of the rear part of the die sleeve corresponding to the air inlet hole, and the air inlet pipe is hermetically connected with the air inlet hole.
The front end of the inner cavity at the front part of the middle die is in a round table shape; the rear end of the rear part of the mold core is arranged in the front end of the inner cavity of the front part of the middle mold, and a sizing material flow passage is reserved between the rear end of the mold core and the inner cavity of the front part of the middle mold.
FIG. 5 is a schematic radial cross-sectional view of the support structure machined from the mold assembly of the present example. In fig. 6, the dashed lines are the cables in the support structure.
Referring to figures 2, 3 and 7, in this example the inlet apertures 12 are circular in cross-section and have a diameter of 5mm and a cross-section of about 20m square meter; the section of the air path (the main air pipe 11) is round or square, and the area is about 0.6m square meter; the section of the bronchus 10 is in a semicircular sector shape; the air outlet 17 of the bronchus is of a circular section, the diameter is 0.6mm, and the length is 20 mm.
The section of the bronchus is fan-shaped, round or square, the section of the air outlet 17 at the center is round, the shape and the structure influence the uniformity of gas distribution and whether the support to the excircle is sufficient, otherwise, the uniformity of air flow or air pressure is influenced; an excessive length may affect the integrity of the inner wall. For example: the air outlet is longer and is easy to extend out of other matched mould structures, so that after the material is extruded, when the air does not fully play a supporting role, the material of the outer layer is cooled and shaped, and the failure is caused.
When the elastic material extruded by the die is used, the ventilation pressure is about 0.5-1 MPA, the ventilation temperature is about 20-30 ℃, the stability of pressure needs to be ensured in the production process, the phenomenon that bulges and depressions occur when the pressure is too large or too small, the shape of a channel is influenced, the uniformity is reduced, and the probability that the product has fault risks is increased. During normal production, the linear speed is not more than 10m/min, the product tolerance control is not more than 0.5mm, the size of the product is strictly controlled by adopting online detection equipment, the fluctuation during production is considered, the size of the cooled product is not more than +/-0.1 mm of a nominal value as much as possible, the uniformity of the product is improved, and the phenomenon that the matching size is different and exceeds the size of the product in the next procedure is prevented, so that the product is poor.
Example 1: by adopting the die assembly, the support body and the outer insulating layer of the elastomer material are extruded outside the insulating wire core with the circular section in an extrusion manner at one time;
the aperture of the mold core is larger than the diameter of the wire core, and the aperture of the mold core is equal to the diameter of the wire core plus 0.3 mm;
the plastic extruding machine adopts a low-smoke halogen-free or cross-linked PE screw. The extruder body adopts the cooling water machine cooling, from feeding to ejection of compact direction, the fuselage warm area is: the first zone is 165 +/-5 ℃, the second zone is 180 +/-5 ℃, the third zone is 185 +/-5 ℃, the fourth zone is 190 +/-5 ℃ and the fifth zone is 190 +/-5 ℃; temperature of machine head and machine neck: first region 195 + -5 deg.C, second region 195 + -5 deg.C, third region 195 + -5 deg.C, fourth region: 195 +/-5 ℃; the machine body and the machine head are heated by adopting a thermocouple.
During insulation extrusion, the negative load of the equipment (extrusion screw) is kept at 120-150A (the power of the extrusion screw can be calculated by current and 3-phase alternating voltage), and during extrusion, circulating cooling air pressure is applied, the air pressure is set to be 0.5MPa, the outer layer of the insulation wire core or the outer insulation layer is not adhered, and the distance is uniformly controlled to be 2 m.
Example 2:
the difference from example 1 is:
the temperature area of the machine body is as follows: the first zone is 100 +/-5 ℃, the second zone is 125 +/-5 ℃, the third zone is 145 +/-5 ℃, the fourth zone is 155 +/-5 ℃ and the fifth zone is 165 +/-5 ℃; temperature of machine head and machine neck: first zone 170 + -5 deg.C, second zone 170 + -5 deg.C, third zone 170 + -5 deg.C, fourth zone: 170 +/-5 ℃.
The equipment load is kept at 90-110A during insulation extrusion, the circulating cooling air pressure is applied during extrusion, the air pressure is set to be 1MPa, the outer layer of the insulated wire core is not adhered to the outer insulation, and the distance is uniformly controlled to be 2 m.
The temperature zone parameters of the machine body are favorite, if the temperature zone parameters are favorite, the equipment load is kept at 110-125A, the air pressure is set to be 1MPa, the outer layer of the insulated wire core is bonded with the outer insulating layer, the distance is measured to be 1mm, the distance is small, and the cooling circulation flow does not meet the requirement;
example 3 (comparative):
the difference from example 1 is: the equipment load during insulation extrusion is kept at 120-150A, and the circulating cooling air pressure is applied during extrusion and is set to be 3 MPa. At this time, the outer insulating layer bulges and cannot meet the requirement.
Comparison between examples 1, 2 and 3:
1) the yield of the cable prepared in example 1 is the highest and reaches 99.1%, and the yield of the cable prepared in example 2 reaches 95%. Example 3 did not meet the production control requirements and comparative description is not included below.
2) The cable product prepared in the example 1 has stable structure, the outer diameter of the wire core is 17.0-17.5 mm, the outer diameter structure is stable and round in size, the central channel structure is stable at 2.0mm, the outer insulating layer is stable at 1.2-1.3 mm, and the roundness is high and the ellipticity is not more than 10%.
3) In the test of the cable obtained in example 1, the pressure of the cooling fluid applied in the tubular through hole 16 of the support structure was between 1.4MPa and 1.5MPa, and the pressure was stable.
4) The cable prepared in example 1 was tested, and the difference between the maximum and minimum surface temperatures of the finished cable (run cable surface temperature test) was only 2 degrees celsius.
5) The cable product prepared in example 2 has an unstable structure, the outer diameter of the wire core is 16.5mm-17.5mm, the structure of the central channel is stable at 1.5mm-2.0mm, the outer insulating layer is 1.1mm-1.3mm, the roundness is insufficient, and the surface of the wire core is easy to be hexagonal.
6) The cable obtained in example 2 was tested, and the pressure of the cooling liquid was between 0.5MPa and 1.0MPa, which was unstable.
7) In the test of the cable prepared in example 2, the difference between the highest surface temperature and the lowest surface temperature of the finished cable (running cable surface temperature test) is more than 5 degrees, so that the condition that the cooling channel is not uniform can be inferred, and the cooling effect is poor.
8) Example 2 the phenomenon of uneven thickness and disjointing appear easily in the cable production process, expose inside insulating core to, the outer insulating layer appears the adhesion with the sinle silk skin easily, can't separate.

Claims (5)

1. A method of extruding a hollow cable support structure, the steps comprising: 1) installing an extrusion die assembly on the plastic extruding machine; 2) according to the extrusion process, the hollow supporting structure is extruded outside the cable, and the method is characterized in that
In the step 1): the extrusion die assembly comprises a die core, a die sleeve combining cap, a middle die and a middle die pressing ring; the center positions of the mold core, the mold sleeve combining cap, the middle mold and the middle mold connecting mechanism are provided with wiring channels for cables to pass through, the wire inlet ends of the wiring channels are arranged in front, and the wire outlet ends are arranged in back;
the shape of the rear part of the mold core is a circular truncated cone shape, and the smaller bottom of the circular truncated cone faces the rear end; the front part of the mold core is provided with a structure connected with the extruder body;
the shape of the front part of the die sleeve is cylindrical, a truncated cone-shaped cavity is formed in the front part of the die sleeve, and the shape of the truncated cone-shaped cavity corresponds to the shape of the rear part of the die core; the rear part of the die sleeve is cylindrical, and a cylindrical cavity is formed in the rear part of the die sleeve; the outer diameter of the rear part of the die sleeve is smaller than that of the front part of the die sleeve;
the radial section of the die sleeve and the die cap is in a ring shape, the inner diameter of the ring corresponds to the outer diameter of the rear part of the die sleeve, and the outer diameter of the ring is larger than the outer diameter of the front part of the die sleeve; the outer wall of the mold sleeve and the outer wall of the mold cap are provided with threads connected with the extruder body;
the rear part of the mold core is arranged in the truncated cone-shaped cavity at the front part of the mold sleeve, and a sizing material runner is reserved between the outer wall of the rear part of the mold core and the truncated cone-shaped cavity; the die sleeve and the cap are sleeved outside the rear part of the die sleeve;
the middle mold consists of a front part, a middle part and a rear part which are connected with each other; the front part of the middle die is in a cylindrical shape, and the radial section of the middle part of the middle die is in a circular ring shape; the outer diameter of the middle part of the middle die is larger than that of the front part of the middle die;
the rear part of the middle mold is formed by a plurality of air outlet separation columns surrounding the wiring channel; the outer diameter of the outer wall of each air outlet separation column which is encircled into a cylindrical shape is smaller than the outer diameter of the middle part of the middle mold;
the middle mold is sleeved in a cylindrical cavity at the rear part of the mold sleeve, the middle mold sleeve is sleeved outside the air outlet spacer, and a sizing material flow channel is reserved between the middle mold sleeve and the air outlet spacer;
the middle die pressing ring presses the middle die sleeve and the middle die from back to front, and the outer wall of the middle die pressing ring is connected with the inner wall of the rear part of the die sleeve through threads;
the shape of the air outlet separation column corresponds to the shape of the inner cavity of the tubular through hole of the processed support structure; the number and the positions of the air outlet separation columns correspond to the number and the positions of the tubular through holes of the processed support structure; the air outlet separation column is parallel to the wiring channel; a through bronchus is arranged in the air outlet partition column, an air outlet of the bronchus faces the rear part of the air outlet partition column, an air inlet of the bronchus is connected with an annular main air pipe, the main air pipe is embedded in the middle part of the middle mold, and an air inlet hole is formed in the middle part of the middle mold and connected with the main air pipe;
an air inlet pipe is arranged on the side wall of the rear part of the die sleeve, which corresponds to the air inlet hole, and the air inlet pipe is hermetically connected with the air inlet hole;
in the step 2): the aperture of the mold core is larger than the diameter of the wire core; the machine body and the machine head are heated by adopting a thermocouple, and the temperature of each temperature zone is set according to the extrusion material; and applying circulating cooling air to the air inlet during extrusion, wherein the air pressure is set to be 0.5-1 MPa.
2. The method for extruding a hollow cable support structure according to claim 1, wherein in step 1), the front end of the inner cavity of the front part of the middle mold of the extrusion mold assembly is in the shape of a circular truncated cone; the rear end of the rear part of the mold core is arranged in the front end of the inner cavity of the front part of the middle mold, and a sizing material flow passage is reserved between the rear end of the mold core and the inner cavity of the front part of the middle mold.
3. The method of extruding a hollow cable support structure according to claim 1, wherein in step 2), the core diameter is +0.3 mm.
4. An extrusion die assembly of a cable hollow supporting structure is characterized by comprising a die core, a die sleeve combining cap, a middle die and a middle die pressing ring; the center positions of the mold core, the mold sleeve combining cap, the middle mold and the middle mold connecting mechanism are provided with wiring channels for cables to pass through, the wire inlet ends of the wiring channels are arranged in front, and the wire outlet ends are arranged in back;
the shape of the rear part of the mold core is a circular truncated cone shape, and the smaller bottom of the circular truncated cone faces the rear end; the front part of the mold core is provided with a structure connected with the extruder body;
the shape of the front part of the die sleeve is cylindrical, a truncated cone-shaped cavity is formed in the front part of the die sleeve, and the shape of the truncated cone-shaped cavity corresponds to the shape of the rear part of the die core; the rear part of the die sleeve is cylindrical, and a cylindrical cavity is formed in the rear part of the die sleeve; the outer diameter of the rear part of the die sleeve is smaller than that of the front part of the die sleeve;
the radial section of the die sleeve and the die cap is in a ring shape, the inner diameter of the ring corresponds to the outer diameter of the rear part of the die sleeve, and the outer diameter of the ring is larger than the outer diameter of the front part of the die sleeve; the outer wall of the mold sleeve and the outer wall of the mold cap are provided with threads connected with the extruder body;
the rear part of the mold core is arranged in the truncated cone-shaped cavity at the front part of the mold sleeve, and a sizing material runner is reserved between the outer wall of the rear part of the mold core and the truncated cone-shaped cavity; the die sleeve and the cap are sleeved outside the rear part of the die sleeve;
the middle mold consists of a front part, a middle part and a rear part which are connected with each other; the front part of the middle die is in a cylindrical shape, and the radial section of the middle part of the middle die is in a circular ring shape; the outer diameter of the middle part of the middle die is larger than that of the front part of the middle die;
the rear part of the middle mold is formed by a plurality of air outlet separation columns surrounding the wiring channel; the outer diameter of the outer wall of each air outlet separation column which is encircled into a cylindrical shape is smaller than the outer diameter of the middle part of the middle mold;
the middle mold is sleeved in a cylindrical cavity at the rear part of the mold sleeve, the middle mold sleeve is sleeved outside the air outlet spacer, and a sizing material flow channel is reserved between the middle mold sleeve and the air outlet spacer;
the middle die pressing ring presses the middle die sleeve and the middle die from back to front, and the outer wall of the middle die pressing ring is connected with the inner wall of the rear part of the die sleeve through threads;
the shape of the air outlet separation column corresponds to the shape of the inner cavity of the tubular through hole of the processed support structure; the number and the positions of the air outlet separation columns correspond to the number and the positions of the tubular through holes of the processed support structure; the air outlet separation column is parallel to the wiring channel; a through bronchus is arranged in the air outlet partition column, an air outlet of the bronchus faces the rear part of the air outlet partition column, an air inlet of the bronchus is connected with an annular main air pipe, the main air pipe is embedded in the middle part of the middle mold, and an air inlet hole is formed in the middle part of the middle mold and connected with the main air pipe;
an air inlet pipe is arranged on the side wall of the rear part of the die sleeve corresponding to the air inlet hole, and the air inlet pipe is hermetically connected with the air inlet hole.
5. The extrusion die assembly of claim 4, wherein the front end of the inner cavity of the front portion of the middle die is in the shape of a truncated cone; the rear end of the rear part of the mold core is arranged in the front end of the inner cavity of the front part of the middle mold, and a sizing material flow passage is reserved between the rear end of the mold core and the inner cavity of the front part of the middle mold.
CN201911228550.8A 2019-12-04 2019-12-04 Extrusion method of cable hollow supporting structure Pending CN110774565A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201911228550.8A CN110774565A (en) 2019-12-04 2019-12-04 Extrusion method of cable hollow supporting structure

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201911228550.8A CN110774565A (en) 2019-12-04 2019-12-04 Extrusion method of cable hollow supporting structure

Publications (1)

Publication Number Publication Date
CN110774565A true CN110774565A (en) 2020-02-11

Family

ID=69393851

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201911228550.8A Pending CN110774565A (en) 2019-12-04 2019-12-04 Extrusion method of cable hollow supporting structure

Country Status (1)

Country Link
CN (1) CN110774565A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114228097A (en) * 2021-12-29 2022-03-25 惠州市新泰欣宏精密模具有限公司 Superfine medical lotus root-shaped foaming high-temperature extrusion machine head and mould

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114228097A (en) * 2021-12-29 2022-03-25 惠州市新泰欣宏精密模具有限公司 Superfine medical lotus root-shaped foaming high-temperature extrusion machine head and mould

Similar Documents

Publication Publication Date Title
JP5297726B2 (en) Coaxial cable hollow core manufacturing method, coaxial cable hollow core, and coaxial cable
JP5959639B2 (en) Concentric coextrusion die and method for extruding multilayer thermoplastic film
US3121255A (en) Apparatus for extruding plastic compounds
CN110774565A (en) Extrusion method of cable hollow supporting structure
US3095608A (en) Process and apparatus for extruding and curing polymeric compositions
CN105291401A (en) Pipe extruder die
CN211251279U (en) Extrusion die assembly of cable hollow supporting structure
CN113334736B (en) Eccentric pre-regulator and method for regulating extrusion molding eccentricity
US3026565A (en) Extruder head for hollow products
US4512944A (en) Methods of and apparatus for insulating a conductor with a plastic material
CN210415460U (en) Double-layer co-extrusion machine head die
JP7058268B2 (en) Microcapillary wire coating die assembly
KR20090060954A (en) Arrangement and method in connection with extrusion tools
JP5603970B2 (en) Manufacturing equipment for hollow core for coaxial cable
CN114464350B (en) Cable and cable extrusion molding process system thereof
CN114407319A (en) Extrusion processing method of rubber and silica gel double-layer sheath wire
US2740989A (en) Extruders
CN210011282U (en) Cable sheath is aircraft nose for extruder with integral type mould
CN116543981A (en) Production line and production method of multilayer coextrusion machine head and wet stator motor winding wire
CN202422865U (en) Machine head of cabtyre cable rubber extruding machine
JP2004055144A (en) Small diameter coaxial cable and its manufacturing method
CN216914773U (en) Three-layer co-extrusion die for cable production
FI70540C (en) FOER REFRIGERATION FOR OIL TILLVERKNING AV EN BANA AV SKUMMAT THERMOPLASTIC MATERIAL
CN217258248U (en) Cable insulation extrusion die
JP2014034158A (en) Mandrel, manufacturing apparatus of resin pipe, and manufacturing method of resin pipe

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination