JP2007325494A - Method for manufacturing water shut-off normal temperature shrinkage reinforcement insulation cylinder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water shut-off normal temperature shrinkage reinforcement insulation cylinder which has favorable water shut-off performance and favorable workability in connection and water shut-off processing and ensures easy operation for cable connection and water shut-off processing even in an environment restricted in the use of a heat source, and a cable connection part using the reinforcement insulation cylinder. <P>SOLUTION: This method for manufacturing a water shut-off normal temperature shrinkage reinforcement insulation cylinder comprises a step for sequentially sliding a reinforcement insulation cylinder 3 to a tapered part 10 and a large diameter part 9 in a diameter expansion tool 8, a step for supporting the normal temperature shrinkage reinforcement insulation cylinder 3 on a cylindrical core 2 with its diameter elastically expanded, a step for forming a water shut-off layer 4 to manufacture a complex cylinder unit and a step for covering an adhesion layer 6 of the complex cylindrical unit and keeping the diameter expanded. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a water-impervious type cold-shrinkable reinforced insulating cylinder used for connecting a power cable.

Conventionally, in order to ensure high reliability of power supply, high water shielding performance is required not only for the power cable body but also for the cable connection portion, and the cable connection portion is subjected to water shielding treatment.
The conventional water-insulating structure of the cable connection part is provided with, for example, a rubber-reinforced insulation cylinder straddling the cable conductor connection part of the plastic insulated power cable represented by cross-linked polyethylene insulation and the cable insulators on both sides thereof, On this reinforced insulating cylinder, a water-impervious heat-shrinkable tube formed by embedding a water-shielding layer formed by winding a metal foil in a cylindrical shape in the circumferential direction in a heat-shrinkable tube is covered, and the tube is heat-shrinked. It is formed in close contact with the outer peripheral surface of the reinforcing insulating cylinder.

In the case of the conventional structure, at the site where the cable connection portion is formed, after the reinforcing insulating cylinder is provided on the cable conductor connecting portion and the like, the water-insulating heat shrinkable tube is put on the reinforcing insulating cylinder, but the outer peripheral surface of the reinforcing insulating cylinder is true. Even if it is made into a distorted shape instead of being circular and covered with a water-proof heat-shrinkable tube, it does not adhere evenly and a minute gap is likely to occur between them. For this reason, when the water is immersed from the gap and the water continues for a long period of time, there is a possibility that the connection portion is deteriorated in insulation.
In addition, the work steps of cable connection and water shielding treatment are increased and the work becomes complicated, and it takes time to work, resulting in poor workability.
Furthermore, a heat source for shrinking the water-insulating heat-shrinkable tube is required, and the use of the heat source is limited, or it is difficult to perform connection and water-insulating treatment in a narrow place.

  The present invention solves the above-mentioned problems, has excellent water shielding performance, has good workability for connection and water shielding treatment, and also has cable connection and water shielding treatment work where the use of a heat source is restricted. The present invention provides a method for producing a water shielding type room temperature shrinkable reinforced insulating cylinder, which provides a water shielding type room temperature shrinkable reinforced insulating cylinder.

  In order to achieve the above object, in the present invention, (1) a large-diameter portion 9, a tapered portion 10 and a small-diameter portion 11 are formed, the large-diameter portion 9 is circular and a cylindrical core is accommodated therein. The expanded diameter expanding jig 8 is inserted into the room temperature shrinkable reinforced insulating cylinder 3 from the small diameter section 11 side, and the reinforced insulating cylinder 3 is sequentially slid to the tapered section 10 and the large diameter section 9 of the expanded diameter jig 8. (2) The reinforcing insulating cylinder 3 is moved beyond the end of the large-diameter portion 9, the reinforcing insulating cylinder 3 is transferred to the cylindrical core, and the room temperature shrinkable reinforcement is formed on the cylindrical core 2. (3) After that, the metal foil 4A sandwiched from both sides by the adhesive layer 6 is piped in the circumferential direction on the outer peripheral surface of the reinforced insulating cylindrical body 3. A step of overlapping the opposite side edges 4B and 4C to form a water shielding layer 4 to form a composite cylindrical body, (4 In a state where the composite cylindrical body is inserted into the large diameter portion 9 of the diameter expansion jig 8 that is slightly larger than that used when expanding the diameter of the reinforced insulating cylindrical body 3, the room temperature shrinkable property is observed from the small diameter portion 11 side. Inserting the waterproof protective layer 5 and sequentially sliding on the outer peripheral surfaces of the tapered portion 10 and the large-diameter portion 9 and finally covering the pressure-sensitive adhesive layer 6 of the composite cylindrical body and supporting it in an expanded state. In addition to the step (4), the step (5) can be dismantled with an inner diameter slightly larger than the outer diameter of the composite cylindrical body. A step of supporting the waterproof protective layer 5 in a diameter-enlarged state in advance on the cylindrical core 2 using the diameter-enlarging jig 8, and (6) expanding on the composite cylindrical body with the cylindrical core 2 The waterproof protective layer 5 supported by the diameter is disposed, and the cylindrical core 2 is dismantled and removed, so that the waterproof protective layer 5 has its self-shrinking force. Method for producing a water-impervious type cold shrinkable reinforcing insulating tube which is characterized by using a step of supporting at expanded state more placed over the composite tubular member is provided.

According to the present invention, a cable insulation and water shielding treatment work is performed using a reinforcing insulating cylinder in which a cold-shrinkable reinforcing insulating cylinder, a water-shielding layer and a cold-shrinking waterproof protective layer are formed in close contact with each other. Therefore, it is possible to attach and cover the reinforcing insulation cylinder, water shielding layer and waterproof protective layer at the same time, reduce the number of connection and water shielding treatment work processes, and perform these work easily and in a short time. Can be increased.
In addition, since the water shielding layer is held in an embedded state in the adhesive layer, there is a gap between the reinforcing insulating cylinder and the water shielding layer and between the water shielding layer and the waterproof protective layer that causes water infiltration. It is difficult to prevent water from entering, and the progress of insulation deterioration of the cable connection portion can be delayed.
Furthermore, since no heat source is required for cable connection and water shielding treatment, these operations can be performed even in places where the use of heat sources is restricted or in places where it is difficult to store heat sources, and work efficiency is improved. .

The present invention is implemented in the form as described above, and has the effects described below.
That is, according to the present invention, the cable connection and the water shielding treatment are performed using the reinforcing insulating cylinder in which the room temperature shrinkable reinforcing insulating cylinder, the water shielding layer, and the room temperature shrinking waterproof protective layer are formed in close contact with each other. Since the work is performed, the installation of the reinforcing insulating cylinder, the water shielding layer and the waterproof protective layer, and the covering work can be performed at the same time, the connection and water shielding treatment work processes are reduced, and these work can be performed easily and in a short time. Workability can be improved.

  In addition, since the water shielding layer is held in an embedded state in the adhesive layer, there is a gap between the reinforcing insulating cylinder and the water shielding layer and between the water shielding layer and the waterproof protective layer that causes water infiltration. It is difficult to prevent water from entering, and the progress of insulation deterioration of the cable connection portion can be delayed.

  Furthermore, since no heat source is required for cable connection and water shielding treatment, these operations can be performed even in places where the use of heat sources is restricted or in places where it is difficult to store heat sources, and work efficiency is improved. be able to.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. As shown in FIG. 1, a water-impervious type cold-shrinkable reinforced insulating cylinder 1 according to the present invention has a cylindrical cylindrical core 2 that can be disassembled and elastically, that is, retains elasticity on the cylindrical core 2. As it is, the room temperature shrinkable reinforced insulating cylinder 3 supported in an expanded state, the water shielding layer 4 formed thereon, and the room temperature shrinkable coating coated on the outer peripheral surface of the water shielding layer 4. The waterproof protective layer 5 and the pressure-sensitive adhesive layer (adhesive layer) 6 that holds the water-impervious layer 4 in an embedded state and adheres the reinforced insulating cylinder 3 and the waterproof protective layer 5 to each other are provided.

  For example, the cylindrical core 2 is formed by spirally winding a string-like string-shaped body made of polypropylene into a cylindrical shape, and welding adjacent string-shaped bodies together so as not to lose its shape. Is done. The cylindrical core 2 is gradually pulled from one end side by pulling the string-like body inward from one end side of the cylindrical core 2 and pulling it out through the hollow hole in the cylindrical core 2 to the other end side. It is configured to be dismantled and removed.

  The reinforced insulating cylinder 3 generally uses ethylene propylene rubber, silicone rubber or the like having high insulation performance and excellent moldability as a base rubber, and the inner conductive layer 3A, the reinforcing insulator 3B, and the outer conductive layer 3C are made up of. A single piece (1 piece) that is integrally molded so as to have a spindle shape, and is radially expanded on the cylindrical core 2 in a radial direction (holding an elastic state). Supported by

As shown in detail in FIG. 2, the water shielding layer 4 is a cylindrical metal foil (including metal film and sheet) 4A made of copper, aluminum, lead, etc. having a thickness of 0.01 to 0.1 mm in a circumferential shape. The opposite side edges 4B and 4C are overlapped with each other by 5 to 20 mm, preferably about 10 to 15 mm, and the overlap portion is sealed in a water-tight manner with an adhesive material. Direction)).
The metal foil 4A is not only formed by bending a single metal foil into a cylindrical shape, but also formed by winding two or more metal foils in the circumferential direction so that both side edges of each foil overlap. May be. Furthermore, the metal foil may be processed into a wave shape (corrugated shape) so as to have elasticity in the circumferential direction. As described above, when a plurality of metal foils or corrugated metal foils are used, even if the water-proof type cold-shrinkable reinforced insulating cylinder 1 is used for cable connection and water-shielding treatment and is shrunk at room temperature, the metal foil is localized. It is effective in suppressing the occurrence of large strains on the surface and preventing the occurrence of cracks and wrinkles.

  The waterproof protective layer 5 is formed into a cylindrical body mainly composed of a rubber material such as styrene butadiene rubber, chloroprene rubber, butadiene rubber, urethane rubber, ethylene propylene rubber, silicone rubber, or fluoro rubber, and is radially formed on the water shielding layer 4. It is supported in an elastically expanded state.

  The adhesive layer 6 is made of, for example, an insulating rubber such as butyl rubber, chloroprene rubber, acrylic rubber, or polyvinyl acetate, or a plastic material.

  Reference numeral 7 denotes a ground member made of a ground wire made of a conductive material such as copper or aluminum, and the reinforcing insulating cylinder 1 is interposed between the reinforcing insulating cylinder 3 and the adhesive layer 6 provided inside the water shielding layer 4. The two ends are arranged so as to be exposed from the end of the cylinder, and are embedded in the reinforcing insulating cylinder 1. The grounding member 7 is connected to the metal shielding layers of the cables on both sides after the reinforcing insulating cylinder 1 is provided on the cable conductor connection portion and the like, and electrically connects both shielding layers. In this embodiment, the grounding member 7 is provided. However, the metal foil 4A of the water shielding layer 4 is used in place of the grounding member, and grounding lead portions are provided at both ends, which are connected to the metal shielding layers of both cables. The shielding layers may be electrically connected to each other.

  The water shielding type room temperature shrinkable reinforced insulating cylinder 1 of the present embodiment is configured as described above. In this insulating cylinder 1, when the cylindrical core 2 is disassembled and removed, the reinforcing insulating cylinder 3 and the waterproof protective layer 5 contract at a normal temperature to reduce the diameter. At this time, since the reinforcing insulating cylinder 3, the grounding member 7, the water shielding layer 4, and the waterproof protective layer 5 are in close contact with each other by the adhesive layer 6, the reinforcing insulating cylinder 1 is connected to the conductor connecting portion of the cable connecting portion or the like. Even if the metal foil 4A constituting the water shielding layer 4 is subjected to local stress and cracking occurs even if it is covered at room temperature, the water shielding performance is excellent. .

Next, the manufacturing method of the said water-impervious type normal temperature shrinkable reinforcement insulation cylinder 1 is demonstrated. First, the room temperature shrinkable reinforced insulating cylinder 3 is supported on the cylindrical core 2 in an elastically expanded state. Specifically, as shown in FIG. 3, a diameter expansion jig 8 including a circular large diameter portion 9 having a cylindrical core insertion hole 9A, a tapered portion 10 and a circular small diameter portion 11 is used.
That is, the cylindrical core 2 is inserted into the cylindrical core insertion hole 9A on the large diameter portion 9 side in the diameter expansion jig 8, and the room temperature shrinkable reinforced insulating cylindrical body 3 is inserted from the small diameter portion 11 side.

  In addition, silicone oil, silicone grease, fluorine oil is provided on the outer peripheral surfaces of the large diameter portion 9, the taper portion 10 and the small diameter portion 11 of the diameter expansion jig 8 in order to facilitate the diameter expansion work of the reinforcing insulating cylinder 3. It is preferable to apply a lubricant such as ethylene glycol or paraffin wax in advance. The lubricant is appropriately selected according to the material of the reinforced insulating cylinder 3 and the like.

Next, the reinforced insulating cylinder 3 is sequentially slid on the outer peripheral surface of the tapered portion 10 and the large diameter portion 9 of the diameter expanding jig 8. And if the front-end | tip of the reinforcement insulation cylinder 3 exceeds the edge part of the large diameter part 9, the reinforcement insulation cylinder 3 will self-shrink and will transfer to the rear-end part of the cylindrical core 2, and the cylindrical core 2 will be by the contraction force. To be gripped.
Further, when the reinforced insulating cylinder 3 is slid onto the outer peripheral surface of the large diameter portion 9 and pushed in, the cylindrical core 2 is gradually extracted from the cylindrical core insertion hole 9A, and the reinforced insulating cylinder 3 is cylindrical. It is completely transferred onto the core 2 and supported on the cylindrical core 2 in an expanded state as shown in FIG.

  Next, a ground wire made of, for example, one or a plurality of copper, aluminum or the like is spirally wound on the reinforcing insulating cylinder 3 along the longitudinal direction thereof, or a plurality of ground wires. A grounding member 7 formed by braiding a plurality of grounding wires or by braiding a braided sheet formed by braiding a plurality of grounding wires vertically into a cylindrical shape, etc., from the both ends of the reinforcing insulating cylinder 3 to a desired length. Fix it so that it can be pulled out. Thereafter, the metal foil 4A sandwiched from both sides by the adhesive layer 6 and embedded in the adhesive layer 6 is wound around the outer peripheral surface of the reinforcing insulating cylinder 3 in the circumferential direction, and both opposite side edges 4B, 4C (illustration omitted) is made to overlap, the overlap part is sealed watertight with an adhesive material, and the water-impervious layer 4 is formed (refer FIG. 5).

Next, the outer peripheral surface of the pressure-sensitive adhesive layer 6 on the water shielding layer 4 is covered with a cold-shrinkable waterproof protective layer 5 to be supported. As a method of covering the waterproof protective layer 5, for example, the following two methods will be described.
The first method is a method using the diameter expansion jig 8. In this case, the diameter expansion jig 8 is one size larger than that used when expanding the diameter of the reinforcing insulating cylinder 3. The diameter expansion method is the same as the diameter expansion method of the reinforced insulating cylinder 3. That is, the composite cylindrical body such as the reinforcing insulating cylindrical body 3 and the water shielding layer 4 supported by the cylindrical core 2 is inserted into the cylindrical core insertion hole 9A on the large diameter section 9 side, and at the normal temperature from the small diameter section 11 side. A shrinkable waterproof protective layer 5 is inserted. And this composite cylindrical body is made to slide on the outer peripheral surface of the taper part 10 and the large diameter part 9 one by one, and finally it covers on the adhesion layer 6 of the said composite cylindrical body, and is made to support in an expanded state. It is.

  In the second method, the waterproof protective layer 5 is preliminarily expanded in diameter using the diameter expansion jig 8 on another cylindrical core 2 having an inner diameter slightly larger than the outer diameter of the composite cylindrical body. Let me support you. Next, the waterproof protective layer 5 whose diameter is supported by the cylindrical core 2 is fitted on the composite cylindrical body, and the cylindrical core 2 is disassembled and removed, whereby the waterproof protective layer 5 is self-contracted. It is a method of covering the composite cylindrical body by force and supporting it in an expanded state.

As shown in FIG. 1, the room temperature shrinkable reinforcing insulating cylinder 3, the grounding member 7, the water shielding layer 4, and the waterproof protective layer are integrally adhered to the cylindrical core 2 by the adhesive layer 6. The water shielding type room temperature shrinkable reinforced insulating cylinder 1 having such a structure is manufactured.

Next, an example in which this water shielding type room temperature shrinkable reinforced insulating cylinder 1 is applied to a cable straight connection portion (intermediate connection portion) will be described with reference to FIGS.
First, as shown in FIG. 6, from the end of two power cables (crosslinked polyethylene insulated power cables) 12 to be connected, a conductor 13, a cable insulator 14, a cable external conductive layer 15, a metal shielding layer 16, and a cable The water shielding layer 17 and the cable sheath 18 are stripped and exposed stepwise.

  Next, the water shielding type cold-shrinkable tubes 19 are respectively passed over the cable sheaths 18 of both power cables 12, and the water-blocking type cold-shrinkable reinforcing insulating cylinder 1 according to the present invention is placed on the cable sheath 18 of one of the power cables 12. To wait in advance.

  The water-impervious cold-shrinkable tube 19 includes a tubular core 20 that can be disassembled, an inner cold-shrinkable tube layer 21 that is supported on the tubular core 20 in an elastically expanded state, and an outer cold-shrinkable tube layer 21. The tube layer 22 is formed by winding a metal foil in a cylindrical shape in the circumferential direction and overlapping opposite side edges thereof, and is formed between the inner cold shrinkable tube layer 21 and the outer cold shrinkable tube layer 22. And a pressure-sensitive adhesive layer 24 that adheres to the inner and outer peripheral surfaces of the water-impervious layer 23 and adheres the water-impervious layer 23 to the cold-shrinkable tube layers 21 and 22. .

Next, the conductors 13 of the two cables 12 are passed through the conductor connection sleeve 25 and abutted, and the conductor sleeve 25 is compressed and clamped to form the cable conductor connection portion 26.
Next, the water-impervious type cold-shrinkable reinforced insulating cylinder 1 kept on the cable sheath 18 covers the cable conductor connecting portion 26 and the cable insulators 14 on both sides thereof, and both ends straddle the cable outer conductive layer 15. Then, it is moved and positioned directly above the cable conductor connecting portion 26.

  Next, the cylindrical core 2 of the water-impervious type room temperature shrinkable reinforced insulating cylinder 1 is gradually disassembled and removed from one end side thereof, and the reinforced insulating cylinder 3 and the waterproof protective layer 5 are gradually self-contracted from one end side. After shrinking at room temperature and disassembling the cylindrical core 2, the water shielding type room temperature shrinkable reinforcing insulating cylinder 1 is mounted so as to cover the cable conductor connection portion 20, the cable insulator 14 on both sides thereof, and the cable outer conductive layer 15.

  Next, the grounding members 7 drawn out from both ends of the water shielding type room temperature shrinkable reinforced insulating cylinder 1 are connected to the metal shielding layers 16 and the metal shielding layers 17 of both power cables by a fixing member 27 such as a binding wire. .

  Next, the adhesive water-tight sheet 28 is wound around the spindle-shaped tapered both ends of the water shielding type room temperature shrinkable reinforcing insulating cylinder 1 and the stepped end of the cable sheath 18. Thereafter, the water-blocking room temperature shrinkable tube 19 that has been waiting in advance on the cable sheath 18 is moved to a position straddling both ends of the spindle-shaped tapered end of the water-blocking room temperature shrinkable reinforcing insulating cylinder 1 and the cable sheath 18, and the cylinder. The core 20 is disassembled and removed, and the cold-shrinkable tube layers 21 and 22 of the tube 19 are shrinked at room temperature. Accordingly, as shown in FIG. 7, the water shielding type room temperature shrinkable tube 19 covers the both ends of the water shielding type room temperature shrinkable reinforcing insulating cylinder 1, the metal shielding layer 16, the metal water shielding layer 17 and the cable sheath 18. The both ends of the water shielding type room temperature shrinkable reinforced insulating cylinder 1 are sealed in an airtight and liquid tight manner.

1 is a longitudinal sectional view of an upper half portion of a water-impervious room temperature shrinkable reinforced insulating cylinder according to the present invention. FIG. 2 is a cross-sectional view illustrating a partially enlarged overlap portion of a metal foil in the water shielding layer of FIG. 1. It is explanatory drawing of the method of expanding and supporting a reinforcement insulation cylinder on the cylindrical core shown in FIG. It is a longitudinal cross-sectional view which shows the state by which the reinforcement insulation cylinder was supported on the cylindrical core by the diameter-expansion method shown in FIG. It is a longitudinal cross-sectional view which shows the state which formed the water-impervious layer in the outer peripheral surface of the reinforcement insulation cylinder shown in FIG. It is upper half part explanatory drawing which shows the method of forming a cable linear connection part using the water-impervious type room temperature shrinkable reinforcement insulation cylinder which concerns on this invention. It is an upper half longitudinal cross-sectional view which shows the cable linear connection part assembled by the method shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Water shielding type room temperature shrinkable reinforcement insulation cylinder 2 Cylindrical core 3 Reinforcement insulation cylinder 3A Inner conductive layer 3B Reinforcement insulator 3C Outer conductive layer 4 Water shielding layer 4A Metal foil 4B Side edge 4C Side edge 5 Waterproof protective layer 6 Adhesive Layer 7 Grounding member 8 Diameter expansion jig 9 Large diameter portion 9A Cylindrical core insertion hole 10 Tapered portion 11 Small diameter portion 12 Power cable 13 Conductor 14 Cable insulator 15 Cable external conductive layer 16 Metal shielding layer 17 Metal shielding layer 18 Cable Sheath 19 Water-proof type room temperature shrinkable tube 20 Tubular core 21 Inside room temperature shrinkable tube layer 22 Outside room temperature shrinkable tube layer 23 Water shielding layer 24 Adhesive layer 25 Conductor connection sleeve 26 Cable conductor connection part 27 Fixing member 28 Adhesive watertight Sheet

Claims (2)

The manufacturing method of the water-impervious type normal temperature shrinkable reinforcement insulation cylinder which has the process of (1)-(4).
(1) From the small diameter part 11 side, the diameter increasing jig 8 which consists of the large diameter part 9, the taper part 10, and the small diameter part 11, the large diameter part 9 is circular, and the cylindrical core is accommodated therein. A step of inserting the reinforcing insulating cylinder 3 into the taper portion 10 and the large diameter portion 9 of the diameter-enlarging jig 8 one after another by inserting it into the room temperature shrinkable reinforcing insulating cylinder 3;
(2) The reinforcing insulating cylinder 3 is moved beyond the end of the large-diameter portion 9, the reinforcing insulating cylinder 3 is transferred to the cylindrical core, and the room temperature shrinkable reinforcing insulating cylinder is placed on the cylindrical core 2. The process of supporting 3 in the state expanded elastically.
(3) Thereafter, the metal foil 4A sandwiched from both sides by the adhesive layer 6 is wound around the outer peripheral surface of the reinforced insulating cylinder 3 in the circumferential direction, and the opposite side edges 4B and 4C are overlapped. The process which forms the water shielding layer 4 and makes it a composite cylindrical body.
(4) With the composite cylindrical body inserted in the large diameter portion 9 of the diameter expansion jig 8 that is slightly larger than that used when expanding the diameter of the reinforced insulating cylindrical body 3, normal temperature is applied from the small diameter portion 11 side. A step of inserting the shrinkable waterproof protective layer 5 and sequentially sliding on the outer peripheral surfaces of the tapered portion 10 and the large diameter portion 9 and finally covering the adhesive layer 6 of the composite cylindrical body and supporting it in an expanded state. . It replaces with the process of (4) of Claim 1, and uses the following process (5) (6), The manufacturing method of the water-impervious type normal temperature shrinkable reinforcement insulation cylinder characterized by the above-mentioned.
(5) A step of supporting the waterproof protective layer 5 in a diameter-expanded state in advance using the diameter-enlarging jig 8 on the dismountable cylindrical core 2 having an inner diameter slightly larger than the outer diameter of the composite cylindrical body. .
(6) The waterproof protective layer 5 expanded in diameter supported by the cylindrical core 2 is disposed on the composite cylindrical body, and the cylindrical core 2 is disassembled and removed, whereby the waterproof protective layer 5 has its self-shrinking force. The step of covering the composite cylindrical body and supporting it in an expanded state.

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