Disclosure of Invention
The invention aims to provide an insulating device for an intermediate joint of an insulated bus and a manufacturing method thereof, which solve the problems that an insulating shielding cylinder is not tight in sealing, wet air enters the cylinder, flashover is easy to form and circuit faults are caused, and in order to realize the aim, the technical scheme of the invention is as follows:
an insulating device for an intermediate joint of an insulated bus comprises an insulating shielding cylinder and flanges at two ends of the insulating shielding cylinder, wherein the insulating shielding cylinder is internally provided with the insulated bus and the intermediate joint of the insulated bus in a penetrating way; the flange is formed by combining an outer ring, a middle ring and a base which are provided with through holes for the insulation bus to pass through, a cylindrical extension part is arranged at the outer side of the through hole of the outer ring, and a pumping/inflating hole is arranged on the base wall of at least one flange or an insulation shielding cylinder; the insulating bus penetrates through the insulating shielding cylinder and the through holes of the flanges, and the middle joint is positioned in a closed space which is defined by the insulating bus, the insulating shielding cylinder and the flanges at the two ends of the insulating shielding cylinder and is filled with insulating gas through the pumping/inflating holes.
The inner side surface of the outer ring through hole is provided with a first inclined surface, and the outer side surface of the middle ring through hole is provided with a second inclined surface; when the outer ring is attached to the middle ring, the first inclined plane corresponds to the second inclined plane to form a conical ring, and a first sealing ring is arranged in the conical ring.
A first annular groove is formed in the annular wall on the inner side of the outer ring, and a second sealing ring is arranged between the outer ring and the middle ring; when the outer ring is mounted and attached to the middle ring, the second sealing ring is arranged between the inside of the first annular groove and the outer wall of the middle ring.
An annular groove II is formed in the annular wall on the inner side of the middle ring, and a sealing ring III is arranged between the middle ring and the base; when the middle ring is mounted and attached to the base, the third sealing ring is arranged between the inside of the second annular groove and the outer wall of the base.
The outer edge of the outer ring is symmetrically provided with a first screw hole, the outer edge of the middle ring is symmetrically provided with a second screw hole, the outer edge of the base is symmetrically provided with a third screw hole, and the positions of the first screw hole, the second screw hole and the third screw hole correspond to each other; when the device is installed, the outer ring, the middle ring and the base are tightly fixed by bolts through the first screw hole, the second screw hole and the third screw hole.
And an annular convex strip is arranged on the outer wall of the extension part.
And the inner side wall of the base is provided with an annular clamping groove, and two ends of the insulating shielding cylinder are clamped into the annular clamping groove.
The air pumping/inflating hole is connected with an air nozzle which is connected with an air pumping/inflating device.
A manufacturing method of an insulating device for an intermediate joint of an insulated bus comprises the following steps:
A. installing an insulating shielding cylinder and flanges at two ends of the insulating shielding cylinder at an intermediate joint of an insulating bus;
B. the air tap is connected with an air pumping/inflating device, and an enclosed space surrounded by the insulated bus, the insulated shielding cylinder and flanges at two ends of the insulated shielding cylinder is pumped into vacuum;
C. after the step B is finished, filling insulating gas into a closed space formed by the insulated bus which is vacuumized, the insulated shielding cylinder and the flanges at the two ends of the insulated shielding cylinder through the vacuumizing/inflating device;
D. and D, after the step C is finished, dismantling the air nozzle and plugging the pumping/inflating hole.
And in the step B, the pumping/inflating device comprises a vacuum pump, a pressure gauge, an insulating gas tank and a control box, after the step B is finished, the vacuum stable condition is observed through the indication of the pressure gauge, and after the vacuum condition is stable, the step C is carried out.
The invention has the advantages that: firstly, under the action of a first inclined plane and a second inclined plane of the conical rings arranged on the outer ring and the middle ring, a first sealing ring is extruded by the first inclined plane and the second inclined plane and then extends to a gap between the flange through hole and the insulated bus, so that the first sealing ring is fully attached to the surface of the insulated bus and is practically sealed; the cylindrical extension part of the outer ring can be fully matched with the outer sealing part, so that the joint of the flange and the insulated bus is more convenient and reliable to seal; thirdly, the insulating gas has good insulativity, and the insulativity at the middle joint of the insulated bus can be effectively ensured by injecting the insulating gas after vacuumizing; the sealing performance of the middle joint of the insulated bus is greatly improved, the possibility of flashover at the middle joint of the insulated bus is greatly reduced, and the safety of electrical operation is protected.
Detailed Description
The invention discloses an insulating device for an intermediate joint of an insulated bus, which comprises an insulated shielding cylinder 2 and flanges 1 at two ends of the insulated shielding cylinder, wherein as shown in figures 1 and 3, an insulated bus 3 and an intermediate joint of the insulated bus are arranged in the insulated shielding cylinder 2 in a penetrating way, the insulated bus 3 penetrates through holes of the insulated shielding cylinder 2 and the flanges 1, and the intermediate joint is positioned in a closed space which is formed by the insulated bus 3, the insulated shielding cylinder 2 and the flanges 1 at the two ends of the insulated shielding cylinder and is filled with insulating gas through a pumping/inflating hole 133; in one embodiment as shown in fig. 1, a pumping/inflating hole 133 is provided in the wall of the base 13 of the end flange 1; in another embodiment as shown in fig. 3, a pumping/inflating hole 133 is provided at one end of the insulation shield cylinder 2.
The air tap 134 is connected to the air pumping/inflating hole 133, the air tap 134 is connected to the air pumping/inflating device, and the air pumping/inflating device first vacuums a closed space surrounded by the insulated bus 3, the insulated shielding cylinder 2 and the flanges 1 at the two ends of the insulated shielding cylinder, and then fills the closed space with insulating gas (the insulating gas usually uses nitrogen, and can also use sulfur hexafluoride and other insulating gases), so that the drying and insulation at the middle joint can be ensured.
In order to ensure the excellent sealing performance of the whole insulating device, the invention simultaneously starts from the external air tightness and the internal air tightness of the insulating device, and solves the problem of the sealing performance of the middle joint of the insulated bus.
Preferably, in order to ensure the external air tightness of the insulating device, that is, the air tightness between the insulating bus 3 and the flanges 1 at two ends of the insulating bus, as shown in fig. 2, the flange 1 comprises an outer ring 11, an intermediate ring 12 and a base 13, each of which has a through hole for the insulating bus 3 to pass through, wherein a cylindrical extension part 112 is arranged outside the through hole of the outer ring 11, and the arrangement of the extension part 112 can help the flange 1 and the insulating bus 3 to be wrapped completely by a thermoplastic sealing material, so that the sealing performance between the insulating bus 3 and the flange 1 outside the insulating device is ensured; further, in order to ensure that the thermoplastic sealing material for sealing does not fall off, the outer wall of the extension part 112 is provided with an annular convex strip 115, so that after the thermoplastic sealing material is cooled, the thermoplastic sealing material is firmly buckled and pressed on the extension part 112, the firmness and the non-falling of the external sealing material of the insulating device are ensured, and the sealing performance is further enhanced.
Preferably, in order to ensure the internal airtightness of the insulating device, that is, the sealing performance in the sealed space enclosed by the insulating bus 3, the insulating shielding cylinder 2 and the flanges 1 at the two ends thereof, as shown in fig. 2, on the one hand, since the surface of the insulating bus 3 is not flat, in order to ensure the airtightness between the insulating bus 3 and the flanges 1, preferably, the inner side surface of the through hole of the outer ring 11 is set as a first inclined surface 113, the outer side surface of the through hole of the middle ring 12 is set as a second inclined surface 123, when the outer ring 11 is fitted to the middle ring 12, the first inclined surface 113 corresponds to the second inclined surface 123 to form a conical ring, a first sealing ring 14 is arranged in the conical ring, the outer ring 11, the first sealing ring 14, the sealing ring 15, the middle ring 12, the sealing ring 16 and the base 13 are sequentially fitted on the insulating pipe bus 3, and when the bolt passes through the first screw, When the middle ring 12 and the base 13 are tightly fixed, the first inclined plane 113 and the second inclined plane 123 of the conical ring, which are formed when the outer ring 11 and the middle ring 12 are mounted and attached, can extrude the first sealing ring 14, and the first inclined plane 113 and the second inclined plane 123 form the conical ring to wrap the sealing ring 14, so that the first sealing ring 14 is forced to extend to a gap between the through hole of the flange 1 and the insulated bus 3 after being extruded, and the gap between the through hole of the flange 1 and the uneven surface of the insulated bus 3 is filled, and real sealing is realized.
On the other hand, as shown in fig. 2, the inner side wall of the base 13 is provided with an annular groove 132 for air tightness between the flange 1 and the insulation shielding cylinder 2, as shown in fig. 1 and fig. 3, the cylinder wall of the insulation shielding cylinder 2 can be inserted into the annular groove 132, and the insulation shielding cylinder 2 is firmly adhered to the base 13 by glue, so as to achieve the purpose of sealing.
On the other hand, in order to solve the problem of the sealing performance of the flange 1, as shown in fig. 2, the outer edge of the outer ring 11 is symmetrically provided with a first screw hole 111, the outer edge of the middle ring 12 is symmetrically provided with a second screw hole 121, the outer edge of the base 13 is symmetrically provided with a third screw hole 131, and the positions of the first screw hole 111, the second screw hole 121 and the third screw hole 131 correspond to each other; an annular groove I114 is formed in the inner side annular wall of the outer ring 11, which is opposite to one side of the middle ring 12, a sealing ring II 15 is arranged between the outer ring 11 and the middle ring 12, when the outer ring 11 is attached to the middle ring 12, the sealing ring II 15 is arranged between the inner side of the annular groove I114 and the outer wall of the middle ring 12, and the arrangement of the sealing ring II 15 can increase the air tightness between the outer ring 11 and the middle ring 12.
Similarly, an inner side wall of the middle ring 12 opposite to the base 13 is provided with a second annular groove 122, a third sealing ring 16 is arranged between the middle ring 12 and the base 13, and when the middle ring 12 is attached to the base 13, the third sealing ring 16 is arranged between the inner side wall of the second annular groove 122 and the outer side wall of the base 13 to increase the air tightness between the middle ring 12 and the base 13.
When the flange is installed, the outer ring 11, the middle ring 12 and the base 13 are tightly fixed by bolts through the first screw hole 111, the second screw hole 121 and the third screw hole 131, and the second sealing ring 15 and the sealing ring 16 ensure the air tightness of the flange 1.
According to the technical scheme, the sealing performance of the insulating device from inside to outside is guaranteed, and the structure guarantee is provided for filling insulating gas into a closed space defined by the insulating bus 3, the insulating shielding cylinder 2 and the flanges 1 at the two ends of the insulating shielding cylinder.
A manufacturing method of an insulating device for an intermediate joint of an insulated bus comprises the following steps:
A. installing an insulating shielding cylinder 2 and flanges 1 at two ends of the insulating shielding cylinder at the middle joint of an insulating bus 3;
B. the air tap 134 is connected with an air pumping/inflating device, and a closed space enclosed by the insulated bus 3, the insulated shielding cylinder 2 and the flanges 1 at the two ends of the insulated shielding cylinder is pumped into vacuum;
as shown in fig. 4, the gas pumping/filling device comprises a vacuum pump 4, a pressure gauge 5, an insulating gas tank 6 and a control box 7, after the vacuum pumping is completed in the step B, the number of the pressure gauge 6 is in a negative pressure state, the vacuum state is observed for a period of time, and if the number of the pressure gauge 6 is not changed, the vacuum state is stable.
C. And after the step B is finished, filling insulating gas into a closed space formed by the vacuumized insulated bus 3, the insulated shielding cylinder 2 and the flanges 1 at the two ends of the insulated shielding cylinder through the pumping/inflating device, and indicating that the insulating gas is full when the pressure gauge 6 indicates that the air pressure in the closed space is recovered to the air pressure value of the external environment.
D. And C, after the step C is finished, removing the air nozzle 134, plugging the drawing/inflating hole 133, setting the drawing/inflating hole 133 as a screw hole, screwing the air nozzle 134 on the drawing/inflating hole 133, and after the insulation gas is filled, plugging the drawing/inflating hole 133 by using a bolt fully coated with thread glue after the air nozzle 134 is removed.
The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. That is, all equivalent changes and modifications made according to the content of the claims of the present invention should be within the technical scope of the present invention.