Explosion-proof mineral insulated power cable
By using seamless copper tube and magnesium oxide powder filling layer in the cable, combined with the design of insulating sheath and copper sheath, the problem of conductor contact with fire caused by cable combustion is solved, and the explosion-proof, flame retardant and mechanical strength of the cable is improved.
Patent Information
- Application Number
- CN202421325621.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-12
- Publication Date
- 2025-03-18
- Estimated Expiration
- 2034-06-12
AI Technical Summary
Existing cables can easily cause the conductor to come into contact with the fire when burned, lose power supply, and may even cause explosions.
Explosion-proof mineral insulated power cables are used, which include conductors, insulating sheaths, copper sheaths and fill layers. The copper sheaths are made of seamless copper tubes. The filling layer is made of magnesium oxide powder material, and arc-shaped grooves are opened on the outer wall of the insulating sheath to enhance sealing.
The cable has good waterproof, moisture-proof, oil-proof and chemical-invasion capabilities, can retardant and flammable oil vapors, gases and flames, has strong explosion-proof performance and mechanical strength, and can maintain stable performance under high temperature conditions.
Smart Images
Figure CN222636903U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of power cables, in particular to an explosion-proof mineral insulated power cable. Background Art
[0002] Cable is a device for transmitting electric energy or signals. It is usually a rope-like cable made of several or several groups of wires (at least two wires in each group). Each group of wires is insulated from each other and often twisted around a center. The entire outer layer is covered with a highly insulating covering. The cable has the characteristics of being powered inside and insulated outside.
[0003] The structure of ordinary cables mainly includes conductors, insulation layers and sheaths. The conductor is the path for electric current and is usually made of copper or aluminum. It needs to have good conductivity. The main function of the insulation layer is to electrically isolate the wire core from the ground and the wire cores of different phases from each other to ensure the transmission of electric energy. The sheath is the outermost layer of the cable and its main function is to protect the cable from external physical and chemical damage.
[0004] However, once the insulation layer and sheath of ordinary cables are burned, the conductor will directly come into contact with the fire, causing the entire cable to lose the ability to supply power or transmit signals, and even explosions. Therefore, an explosion-proof mineral insulated power cable is urgently needed to solve the above problems. Utility Model Content
[0005] The utility model aims to solve the shortcomings of the prior art and proposes an explosion-proof mineral insulated power cable, which has the advantages that the entire cable is protected from water, moisture, oil and some chemical substances, and flame retardant to the spread of flammable oil vapor, gas and flame. In addition, since the cable adopts a seamless copper tube as the copper sheath, it has considerable mechanical strength and thus has the characteristics of good explosion-proof performance and strong explosion-proof ability.
[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:
[0007] An explosion-proof mineral insulated power cable comprises five groups of conductors. The outer walls of the five groups of conductors are all provided with insulating sheaths. A copper sheath is provided outside the insulating sheath. A filling layer is filled in the gap between the copper sheath and the insulating sheath. A buffer layer, an outer sheath and a wear-resistant layer are respectively provided outside the copper sheath.
[0008] Through the above technical solution: the entire cable has considerable mechanical strength, and thus has the characteristics of good explosion-proof performance and strong explosion-proof ability.
[0009] The utility model is further configured that the filling layer is made of magnesium oxide powder material.
[0010] Through the above technical solution: the filling layer is filled with magnesium oxide powder, which will not form carbides when encountering high temperatures, so that the overall performance of the entire cable will not change even if it is damaged, and it can continue to work normally.
[0011] The utility model is further configured such that the circumferential outer wall of the insulating sheath is provided with a second arc groove and a first arc groove which are equidistantly distributed in a circle, the second arc groove is close to the center of the conductor, the second arc groove is connected to the first arc groove, and the inner diameter of the second arc groove is smaller than the inner diameter of the first arc groove.
[0012] Through the above technical solution, magnesium oxide powder can be filled into the first arc groove and the second arc groove during the filling process, so that the connection between the filling layer and the insulating sheath is tighter.
[0013] The utility model is further configured that the buffer layer is provided with equidistantly distributed cavities, and the cross section of the cavity is elliptical.
[0014] Through the above technical solution: when the cable is accidentally hit by a heavy object, a part of the stress can be absorbed by the cavity inside the buffer layer, thus playing a good buffering role.
[0015] The utility model is further configured that a group of cavities are provided with stress nodes inside, and the stress nodes are distributed at equal distances inside the cavities.
[0016] Through the above technical solution: the stress nodes at both ends of the cavity can not only support the entire buffer layer, but also when the cavity is deformed by external impact, the stress nodes can share part of the impact force, thereby ensuring the buffering capacity of the cavity.
[0017] The utility model is further configured that the outer sheath is made of low-smoke halogen-free material.
[0018] Through the above technical solution, the outer sheath has low smoke emission when heated and does not contain halogen, so no toxic gas is released.
[0019] The utility model is further configured that the wear-resistant layer includes wear-resistant strips and guide strips arranged on the circumferential outer wall of the outer sheath, and the wear-resistant strips and guide strips are distributed in an equidistant circle on the circumferential outer wall of the wear-resistant layer.
[0020] Through the above technical solution: when laying, it will rub against the ground. At this time, the wear-resistant strip will first rub against the ground, which plays a good protective role for the outer sheath. At the same time, the staff can also judge the wear condition of the entire cable by observing the vertical height of the wear-resistant strip.
[0021] The utility model is further configured such that a group of guide strips is arranged in the middle of the two groups of wear-resistant strips.
[0022] Through the above technical solution: the guide strip can raise the height between the two sets of wear-resistant strips to avoid excessive accumulation of water, impurities and insect eggs between the wear-resistant strips, which may cause damage to the cable.
[0023] The beneficial effects of the utility model are:
[0024] In the utility model, the cable has the functions of preventing the invasion of water, moisture, oil and some chemical substances, and preventing the spread of flame-retardant flammable oil vapor, gas and flame. Specifically, the filling layer and copper sheath are set. In the process of cable production and preparation, the conductor, the filling layer, the insulating sheath and the copper sheath are densely compacted, so that the sealing performance of the whole cable is well guaranteed. At the same time, the copper sheath in the cable is made of seamless copper tube, so that the whole cable has considerable mechanical strength, and thus has the characteristics of good explosion-proof performance and strong explosion-proof ability. The filling layer is filled with magnesium oxide powder, which will not form carbide when encountering high temperature, so that the overall performance of the whole cable will not change even if it is damaged, and it can continue to work and use normally.
[0025] The utility model ensures the tightness of the compaction between the filling layer and the insulating sheath, and further improves the sealing of the entire cable. Specifically, by providing a first arc groove and a second arc groove on the outer wall of the insulating sheath, magnesium oxide powder can be filled into the first arc groove and the second arc groove during the filling process, thereby making the connection between the filling layer and the insulating sheath tighter.
[0026] The utility model can realize that the entire cable has good pressure resistance and wear resistance, and further prolongs the service life of the cable. Specifically, through the provision of a buffer layer and a wear-resistant layer, during the cable laying process, due to its own large weight, it will rub against the ground during laying. At this time, the wear-resistant strip will first rub against the ground, and play a good protective role for the outer sheath. At the same time, the staff can also judge the wear condition of the entire cable by observing the vertical height of the wear-resistant strip. During the normal operation of the cable after the cable is laid, when the cable is accidentally hit by a heavy object, a part of the stress can be absorbed by the cavity inside the buffer layer, which plays a good buffering role, thereby avoiding the situation where the copper sheath is damaged and seriously affects the subsequent normal operation of the cable. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 This is a front view of an explosion-proof mineral insulated power cable proposed by the utility model;
[0028] Figure 2 This is a schematic diagram of the structure of an explosion-proof mineral insulated power cable proposed by the utility model;
[0029] Figure 3This is a schematic diagram of an overall half-section plan view of an explosion-proof mineral insulated power cable proposed by the utility model;
[0030] Figure 4 This is a schematic diagram of the end face of an explosion-proof mineral insulated power cable proposed by the utility model;
[0031] Figure 5 An explosion-proof mineral insulated power cable proposed by the utility model Figure 4 A schematic diagram of the enlarged structure at A in the middle;
[0032] Figure 6 The utility model is a schematic diagram of the split structure of an explosion-proof mineral insulated power cable.
[0033] In the figure: 1. conductor; 2. insulating sheath; 3. filling layer; 4. copper sheath; 5. buffer layer; 6. cavity; 7. outer sheath; 8. wear-resistant layer; 8001. wear-resistant strip; 8002. guide strip; 9. stress node; 10. first arc groove; 11. second arc groove. DETAILED DESCRIPTION
[0034] The technical solution of this patent is further described in detail below in conjunction with specific implementation methods.
[0035] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.
[0036] In the description of this patent, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing this patent and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this patent.
[0037] In the description of this patent, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "set" should be understood in a broad sense, for example, it can be fixedly connected or set, or it can be detachably connected or set, or connected or set in one piece. For ordinary technicians in this field, the specific meanings of the above terms in this patent can be understood according to specific circumstances.
[0038] Reference Figure 1-Figure 6, an explosion-proof mineral insulated power cable, comprising conductors 1, the number of the conductors 1 is five, the circumferential outer walls of the five groups of conductors 1 are all provided with insulating sheaths 2, the outer surfaces of the insulating sheaths 2 are provided with copper sheaths 4, and the gap between the copper sheaths 4 and the insulating sheaths 2 is filled with a filling layer 3;
[0039] The copper sheath 4 is provided with a buffer layer 5, an outer sheath 7 and a wear-resistant layer 8 on its exterior.
[0040] In order to ensure the insulation and explosion-proof capability of the entire cable, refer to Figure 2 The filling layer 3 is made of magnesium oxide powder material. The filling layer 3 is filled with magnesium oxide powder, which will not form carbides when encountering high temperatures, so that the overall performance of the entire cable will not change even if it is damaged, and it can continue to work normally.
[0041] In order to further improve the sealing of the cable interior, refer to Figure 5 The circumferential outer wall of the insulating sheath 2 is provided with a second arc groove 11 and a first arc groove 10 which are equidistantly distributed in a circle. The second arc groove 11 is close to the center of the conductor 1. The second arc groove 11 is connected to the first arc groove 10. The inner diameter of the second arc groove 11 is smaller than the inner diameter of the first arc groove 10. During the filling process, the magnesium oxide powder can be filled into the first arc groove 10 and the second arc groove 11 through the first arc groove 10 and the second arc groove 11 provided on the outer wall of the insulating sheath 2, thereby making the connection between the filling layer 3 and the insulating sheath 2 tighter.
[0042] In order to improve the compressive buffering capacity of the cable, refer to Figure 3-Figure 4 The buffer layer 5 is provided with equidistantly distributed cavities 6, and the cross section of the cavity 6 is elliptical. During the normal operation of the cable after the cable is laid, when the cable is accidentally hit by a heavy object, part of the stress can be absorbed by the cavity 6 inside the buffer layer 5, thereby playing a good buffering role.
[0043] In order to ensure the support capacity of the buffer layer 5, refer to Figure 3 A group of cavities 6 are provided with stress nodes 9 inside, and the stress nodes 9 are distributed at equal distances inside the cavity 6. The stress nodes 9 at both ends of the cavity 6 can not only support the entire buffer layer 5, but also when the cavity 6 is deformed by external impact, the stress nodes 9 can share part of the impact force, thereby ensuring the buffering capacity of the cavity 6.
[0044] In order to make the whole cable have good flame retardant performance, refer to Figure 1 The outer sheath 7 is made of low-smoke halogen-free material. The outer sheath 7 made of low-smoke halogen-free material has low smoke emission when heated and does not contain halogen itself, so it will not release toxic gases.
[0045] In order to ensure the overall wear resistance of the cable, refer to Figure 4 The wear-resistant layer 8 includes wear-resistant strips 8001 and guide strips 8002 arranged on the circumferential outer wall of the outer sheath 7. The wear-resistant strips 8001 and the guide strips 8002 are distributed in an equidistant circle on the circumferential outer wall of the wear-resistant layer 8. When the staff needs to lay the cable, due to its own heavy weight, it will rub against the ground during laying. At this time, the wear-resistant strips 8001 will first rub against the ground, which plays a good protective role on the outer sheath 7. At the same time, the staff can also judge the wear condition of the entire cable by observing the vertical height of the wear-resistant strips 8001.
[0046] In order to avoid excessive accumulation of water, impurities and insect eggs between the wear-resistant strips 8001, refer to Figure 5 A set of guide strips 8002 is set in the middle of the two sets of wear-resistant strips 8001. The set guide strips 8002 can raise the height between the two sets of wear-resistant strips 8001 to avoid excessive accumulation of water, impurities and insect eggs between the wear-resistant strips 8001, which may cause damage to the cable.
[0047] Working principle: During the production and preparation of the cable, the conductor 1, the filling layer 3, the insulating sheath 2 and the copper sheath 4 are compacted bodies, so that the sealing performance of the entire cable is well guaranteed. At the same time, the copper sheath 4 in the cable is made of seamless copper tube, so that the entire cable has considerable mechanical strength, and thus has the characteristics of good explosion-proof performance and strong explosion-proof ability. The filling layer 3 is filled with magnesium oxide powder, which will not form carbides when encountering high temperatures, so that the overall performance of the entire cable will not change even if it is damaged, and it can continue to work normally. At the same time, during the filling process of magnesium oxide powder, the first arc groove 10 and the second arc groove 11 are opened on the outer wall of the insulating sheath 2, so that the magnesium oxide powder can be filled in the filling process. Into the first arc groove 10 and the second arc groove 11, so that the filling layer 3 and the insulating sheath 2 are connected more tightly. When the staff needs to lay the cable, due to its own heavy weight, it will rub against the ground during laying. At this time, the wear-resistant strip 8001 will first rub against the ground, which has a good protective effect on the outer sheath 7. At the same time, the staff can also judge the wear condition of the entire cable by observing the vertical height of the wear-resistant strip 8001. During the normal operation of the cable after the laying is completed, when the cable is accidentally hit by a heavy object, the cavity 6 inside the buffer layer 5 can absorb part of the stress, which has a good buffering effect, avoiding the situation where the copper sheath 4 is damaged and seriously affects the subsequent normal operation of the cable.
[0048] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.
Claims
1. An explosion-proof mineral insulated power cable, comprising a conductor (1), characterized in that: The number of the conductors (1) is five groups, the circumferential outer walls of the five groups of conductors (1) are all provided with insulating sheaths (2), a copper sheath (4) is provided outside the insulating sheath (2), and a filling layer (3) is filled in the gap between the copper sheath (4) and the insulating sheath (2); The copper sheath (4) is provided with a buffer layer (5), an outer sheath (7) and a wear-resistant layer (8) on the outside thereof.
2. An explosion-proof mineral insulated power cable according to claim 1, characterized in that: The circumferential outer wall of the insulating sheath (2) is provided with second arc-shaped grooves (11) and first arc-shaped grooves (10) which are equidistantly distributed in a circular pattern, the second arc-shaped grooves (11) being close to the center of the conductor (1), the second arc-shaped grooves (11) being connected to the first arc-shaped grooves (10), and the inner diameter of the second arc-shaped grooves (11) being smaller than the inner diameter of the first arc-shaped grooves (10).
3. An explosion-proof mineral insulated power cable according to claim 2, characterized in that: The buffer layer (5) is provided with equidistantly distributed cavities (6) inside, and the cross section of the cavity (6) is elliptical.
4. An explosion-proof mineral insulated power cable according to claim 3, characterized in that: A group of the cavities (6) are provided with stress nodes (9) inside, and the stress nodes (9) are distributed at equal distances inside the cavities (6).
5. An explosion-proof mineral insulated power cable according to claim 4, characterized in that: The wear-resistant layer (8) comprises wear-resistant strips (8001) and guide strips (8002) arranged on the circumferential outer wall of the outer jacket (7), and the wear-resistant strips (8001) and the guide strips (8002) are both distributed in a circular shape at equal distances on the circumferential outer wall of the wear-resistant layer (8).
6. An explosion-proof mineral insulated power cable according to claim 5, characterized in that: A group of guide strips (8002) is arranged in the middle of the two groups of wear-resistant strips (8001).