CN110797791B

CN110797791B - Method for overhauling lower 500kVGIL tubular bus without accompanying shutdown

Info

Publication number: CN110797791B
Application number: CN201911068004.2A
Authority: CN
Inventors: 魏忠明; 李晓明; 杨昆鹏; 闫韬; 普俊文; 严峰; 李新明; 杨云武; 杨猛; 赵红伟; 王辉林; 果家礼; 陈忠伟; 李富元; 朱德辉; 王晓军; 任汉智; 周愈能; 字杨; 王俊卿
Original assignee: Yunnan Power Transmission And Distribution Engineering Co ltd
Current assignee: Yunnan Power Transmission And Distribution Engineering Co ltd
Priority date: 2019-11-04
Filing date: 2019-11-04
Publication date: 2021-01-26
Anticipated expiration: 2039-11-04
Also published as: CN110797791A

Abstract

The invention relates to a method for overhauling a lower 500kVGIL tubular bus without accompanying shutdown, which comprises the following steps: and the GIL equipment gas management is used for maintaining the 500kV lower GIL tubular bus in a high-quality, safe and efficient manner without accompanying shutdown, and recovering the gas chamber management of the GIL equipment. According to the invention, only the lower-layer GIL equipment to be overhauled is powered off, the power-off range is not required to be expanded, and the power supply reliability of the system is improved; the output load is increased; the potential safety hazard is small, less safety risks can be controlled, and the cross of working faces is less, so that the safety and civilized construction appearance can be ensured; the time consumed by continuous work is short, and the work efficiency is high; the limit of insufficient safety distance is small.

Description

Method for overhauling lower 500kVGIL tubular bus without accompanying shutdown

Technical Field

The invention relates to a method for overhauling a tubular bus, in particular to a method for overhauling a lower 500kVGIL tubular bus without accompanying shutdown, and belongs to the field of electric power overhauling.

Background

The 500kV GIL tubular bus is important equipment connected between a 500kV GIS and a 500kV outgoing line high-voltage bushing, the GIS and the GIL tubular bus are matched, so that the occupied area, the overhaul (installation time), the equipment maintenance investment and the like are greatly saved, and the GIS and the GIL tubular bus are widely applied to transformer substations and converter stations with voltage levels of 500kV and above due to obvious advantages. In consideration of convenience in overhaul, convenience in extension and the like, the three phases of the 500kV GIL tubular bus A, B, C are mostly horizontally arranged in an upper layer and a lower layer, the length of a standard section is 12 meters, the outer diameter is 0.6 meter, the weight is about 1 ton, the distance between the upper layer tubular bus and the lower layer tubular bus is about 500mm, the horizontal distance between shells of the GIL tubular buses is about 300mm, a plurality of sections of the GIL tubular buses are supported and fixed through steel supports, and the GIL tubular buses passing through a highway are designed to be heightened and overhead; in order to meet the requirements of earthquakes and the like, the steel support is an integral workpiece formed by one-step welding except that the lower layer B-phase GIL tubular busbar supporting cross arm is connected with the upright post through bolts. If the hoisting method is improper during recovery or removal, not only can potential safety hazards be brought to electrified operation equipment, but also major equipment accidents can be caused.

At present, the maintenance work is usually carried out by a machine with smaller output load of a transformer substation or a converter station in a way of simultaneously powering off and maintaining (simultaneously stopping and simultaneously maintaining) the upper and lower GIL tubular buses. During the same stop, the upper GIL tubular busbar is firstly removed and then the lower layer is removed, but the lower layer and the upper layer must be recovered firstly when the lower layer and the upper layer are recovered, so that the lower layer and the upper layer are certainly consumed in waiting for a period of time. The adoption of the simultaneous stop mode with a plurality of points and a plurality of wide battle lines leads to narrow working surfaces and brings about a plurality of problems: 1. the power failure range is expanded, and the system reliability is reduced. 2. The output load decreases. 3. The cross of working faces has many potential safety hazards, and the safety and civilized construction appearance is poor. 4. The time consumed is much, and the working efficiency is low. 5. Limited by insufficient safety distance, and low working efficiency. Therefore, the lower-layer GIL tubular bus must be safely hoisted section by section in a scientific and reasonable mode.

Disclosure of Invention

The invention aims to solve the problems in the prior art and provides a method for overhauling a lower GIL tubular bus under the condition that a 500kV upper GIL tubular bus is not accompanied by shutdown, with high quality, safety and high efficiency.

The purpose of the invention is realized by the following technical scheme:

a method for overhauling a lower 500kVGIL tubular bus without accompanying shutdown comprises the following steps:

step (1), gas management of GIL equipment:

vacuumizing the gas cylinder by using an SF6 gas processing auxiliary device, recovering gas in the gas chamber to half pressure, then removing a conductor connecting transition gas chamber connecting pipe between the GIL and the GIS, recovering residual gas in the gas chamber, uncovering the gas chamber to recover the residual gas, then carrying out gas purification, vacuumizing the gas cylinder, and pressing the purified gas into the gas cylinder;

step (2), overhauling is carried out on the 500kV lower GIL tubular bus under the condition of non-accompanying shutdown

After hoisting, dismantling or re-installing typical difficult positions, wherein the typical difficult positions comprise the lower-layer intermediate phase GIL tubular bus of the ground overlapping part; the lower layer of the multi-section GIL tubular bus is short of the safety distance with the adjacent charged body and is overlapped with the adjacent charged body at the high altitude; the lower-layer middle-phase GIL tubular bus vertical corrugated pipe passes through the high-altitude overlapped part of the highway, and has insufficient safety distance with the adjacent charged body; passing through a lower middle phase GIL tubular bus of the high-altitude overlapped part of the highway; the lower layer A, C phase GIL tubular bus passes through the high-altitude overlapped part of the highway; the ultra-high and ultra-long vertical overlapped part of the inner layer A, C-phase GIL tubular bus; the ultrahigh and overlong vertical overlapped part of the inner-layer intermediate phase GIL tubular bus;

step (3) recovering GIL equipment air chamber management

The method comprises the steps of sequentially positioning tubular buses from the GIS interface side when the tubular buses are dismantled, cleaning a sealing surface on the ground, then temporarily sealing, hoisting, cleaning again after hoisting, confirming that no remnants exist, then butting, filling dry air with the dew point higher than-40 ℃ into an air chamber if the humidity exceeds or is close to 70%, then testing loop resistance, replacing an adsorbent, vacuumizing, detecting leakage under negative pressure, breaking the vacuum by using an SF6 gas processing auxiliary device at the negative pressure stage, then inflating and statically releasing, adjusting the pressure, performing a sampling test, and finally detecting the leakage and injecting glue.

Further, in the step (1), the gas treatment auxiliary device in the gas management of the GIL equipment comprises a gas cavity and a plurality of SF6 gas cylinders connected with the gas cavity, the SF6 gas cylinders are distributed on two sides of the gas cavity, valves of a SF6 gas cylinder body are communicated with the gas cavity through DN10 high-pressure valves, one side of one end of the gas cavity is connected with the SF6 gas treatment device through a first DN20 high-pressure valve, the SF6 gas treatment device is connected with one end of a four-way joint through a second DN20 high-pressure valve, and the other end of the four-way joint is communicated with the other side of one end of the gas cavity through a third DN20 high-; one of the other two ends of the four-way joint is connected with a control system of an air chamber of SF6 electrical equipment, the other end of the four-way joint is connected with one end of the three-way joint through a DN10 high-pressure valve, the second end of the three-way joint is connected with a pressure reducing valve, and the pressure reducing valve is connected with the air chamber through a DN10 high-pressure valve.

Further, in the step (1), the gas management of the GIL facility specifically comprises the following steps:

1.1 evacuation of the gas cylinder

Checking whether the fittings are intact; pumping for 10 minutes when the vacuum degree reaches 5 Pa; then shutting down; SF6 gas state signboard filled on the gas cylinder;

1.2 recovering the gas in the gas chamber to half pressure, removing the conductor to connect a connecting pipe of the transition gas chamber, and leading the high-pressure gas down from the high altitude through a high-pressure pipeline; in the initial stage of gas recovery, the flow is controlled by a valve, and the gas is directly charged into the gas cylinder from the gas chamber by utilizing the pressure difference formed by high vacuum in the gas cylinder and high pressure in the gas chamber;

before the air chambers are vacuumized, the adjacent air chambers can be vacuumized after half pressure reduction; when the gas of the GIL and the transition gas chamber is recovered to be half pressure, the machine is stopped firstly, and a high-pressure pipeline with a conductor communicated with the transition gas chamber is removed;

1.3 recovery of residual gas from the gas cell

After a high-pressure pipeline communicated with the transition gas chamber is dismantled, the residual gas in the GIL gas chamber can be continuously recovered;

1.4 uncovering and recovering residual gas

Fixing a pipeline wrapped by double-layer plastic cloth at the pipe orifice of the tubular bus, introducing the other end of the pipeline into a plastic cylinder, and extending a high-pressure pipeline of the SF6 gas treatment device into the plastic cylinder to start up the machine and recover residual gas;

1.5 post-purification gas bottle

The purified and purified gas can be filled into the gas cylinder which is vacuumized again after passing the test, and the weight is monitored in real time by using a platform scale during the gas filling.

Further, in the step (2), when the lower-layer intermediate-phase GIL tubular busbar at the ground overlapping part is disassembled after the gas in the related gas chamber SF6 is recovered, firstly, a high-strength bamboo fiberboard is paved on the ground of the common dividing stone of the conveying path; then, two rotary hydraulic support transfer trucks arranged on the high-strength bamboo fiber board are conveyed to the lower part of the bus to jack up and take off the tubular bus of the connecting bolt; moving the disassembled bus section to the left to separate the contacts at the right side; in the process, the suspended lower GIL tubular bus can freely move in the positive and negative directions of the three-dimensional space on the rotary hydraulic support transfer trolley, so that the flange with the largest diameter on the right side is prevented from impacting the steel support; pulling out the right side of the bus section outwards, sealing the flange surface for dust prevention, and transporting the bus section out of a disassembling site by using a crane; before the flange is disassembled, marking names on the corresponding section of the tubular bus, and drawing marks on the connecting flange;

during installation, after the tubular bus is in place, the dustproof plastic cloth for transportation, the sealing surface cleaning and the sealing ring placing are required to be dismantled, after the fact that no objects are left in the air chamber is confirmed, the flange hole of the tubular bus moves slowly along the positioning pin to enable the conductor to be inserted firstly, then the two flange surfaces are tightly attached through the light tightening clamp, then the bolt penetrates through the flange hole and is fastened, and finally the remaining bolt penetrates through the flange hole and is fastened.

Further, in the step (2), for the multi-section lower-layer GIL tubular bus which is short in safety distance with the adjacent charged body and is overlapped with the high altitude, the number and the positions of the wheel disc fast-assembly bearing scaffolds and the transfer trolley which need to be erected are calculated according to parameters such as the safety distance requirement, the site condition, the position of a grounding block on the tubular bus, the length of the tubular bus to be displaced and the like;

after laying high-strength bamboo fiber boards on the surface of the centimeter stone, firstly, quickly mounting a bearing scaffold by using a wheel disc to build a supporting platform; then, after leveling and aligning the scaffold by using an adjusting base sleeved on the upright post of the supporting platform, a steel pipe fastener is used for fastening an inclined supporting end support; pre-laying a wood board and a high-strength bamboo fiberboard on the top of the supporting platform; finally, erecting a skirting rail at a position of about 180 mm above the top of the supporting platform by using a steel pipe fastener; jacking up and supporting the GIL tubular bus by a plurality of rotary hydraulic support transfer trucks arranged on the wheel disc quick-mounting bearing scaffold, horizontally moving a plurality of sections of lower-layer GIL tubular buses to a safe region far away from a charged body on the hydraulic support transfer trucks, and safely dismantling or recovering the lower-layer GIL tubular buses;

during installation, the first section of tubular busbar is hoisted to a rotary hydraulic support transfer trolley in a safe area and is firstly displaced to the position below the high-altitude overlapped upper layer live operation tubular busbar; and then, the second section of tubular busbar is connected and then displaced, so that the plurality of sections of tubular busbars are displaced to the target position to be connected and fastened.

Further, in the step (2), for the lower-layer middle-phase GIL tubular busbar vertical corrugated pipe which is not enough in safe distance with an adjacent charged body and passes through a high-altitude overlapped part of a highway, two steel plates are used, continuous three bolt holes of a tubular busbar tee-joint circumferential flange are set out and drilled on the side of each steel plate with the distance of 200mm, the inner side sizes of two flange surfaces of the tubular busbar tee-joint are measured, two flat steels are used for blanking, the two flat steels are arranged in a T shape and welded at the end heads of the non-drilled sides of the two steel plates, and a lifting tool is manufactured;

fixing a lifting and hoisting tool on the top of the lower-layer GIL tubular busbar tee by using a flange connecting bolt, winding two nylon hanging belts on the tool, and respectively hooking two chain hoists on hanging belt hanging rings;

the two nylon hanging belts are respectively encircled on a square flange below a vertical corrugated pipe expansion joint of the tubular bus, and then the two hanging belt lifting rings are respectively hooked on the other ends of the two chain hoists;

tightening the two chain hoists, and removing the lower tee joint and the vertical corrugated pipe telescopic joint flange connecting bolt;

and operating the two chain hoists to slowly disassemble and unload the vertical corrugated pipe to the ground.

Further, in the step (2), the lower-layer intermediate phase GIL tubular bus passing through the high-altitude overlapped part of the highway is carried out according to the following steps:

1. after the trial hoisting is horizontal, commanding a crane to slowly hoist the tubular bus by about 50 mm; a high-strength bamboo fiber plate is stuffed between the tubular bus fixing plate and the square iron tower fixing base;

2. commanding the crane to adjust and slowly hang the lower GIL tubular bus with the tee joint in the middle phase to pass through the square iron tower hole;

3. dismantling a double-upright-column cross arm and a double-upright-column inclined iron between the lower-layer intermediate-phase lower-layer GIL tubular busbar in a short time;

4. a command crane slowly and vertically lifts the lower-layer GIL tubular bus of the lower-layer intermediate phase onto a ground V-shaped transport frame, and a special three-way transport sealing plate is arranged on a three-way flange surface; during hoisting, the lifting appliance vertically moves up and down in a gap between the AB phase and the BC phase of the upper-layer GIL tubular bus, and always keeps a preset distance from the upper-layer GIL tubular bus in live operation, so that the upper-layer GIL live tubular bus is not subjected to extra stress in the whole process, and live operation equipment can reliably operate; the whole hoisting process is to ensure that the conductor extending out of the lower plane of the flange surface of the tubular bus tee joint is not collided and damaged.

Further, in the step (2), the A, C-phase GIL tubular bus bar at the lower layer of the overhead overlapping part of the over-road is processed as follows:

when the hanger is detached, the assembly hook of the anti-skid hanger is hung on a large hook of a crane, the sling at the inner side penetrates through the gap of the upper-layer side phase GIL tubular bus, and the anti-skid sling is respectively looped on the side phase GIL tubular bus; putting down a pair of lifting belts hooked on the small hooks along the outer sides of the side phase tubular buses, and wrapping the lifting belts on the tubular buses by using a tool U-shaped ring;

slowly hoisting the steel support to the upper surface of the lower layer GIL tubular bus and almost touching the lower surface of the steel support cross arm of the upper layer GIL tubular bus; then, loosening the anti-skidding lifting appliance on the big hook by tightening the hanging strip edge of the small hook, gradually displacing the lower-layer GIL tubular bus to the outer side of the steel support until the big hook is completely loosened and all loads are transferred to the small hook, and completely separating the lower-layer GIL tubular bus from the steel support supporting cross arm; then hoisting the lower GIL tubular busbar of the side phase to the ground with the tee joint and the vertical corrugated pipe for further dismantling;

when the anti-skid hanger is installed, the anti-skid hanger is firstly hooked on a hook of a crane; then the hanging strip and the tool U-shaped annular pocket tubular bus are hooked on the small hook; then, hoisting the lower-layer GIL tubular bus of the side phase to the side of a set position by using a small hook, enabling a sling at the inner side of the sling, which is hooked on a large hook of a crane, to penetrate through the gap of the upper-layer middle-phase GIL tubular bus, and respectively looping an anti-skidding sling on the side-phase GIL tubular bus; and finally, commanding the big hook and the small hook of the crane to be matched, loosening and tightening, and gradually displacing the lower layer GIL tubular busbar to the position below the upper layer GIL tubular busbar by using a relative hoisting method.

Further, in the step (2), the ultra-high and ultra-long vertical overlapping part inner layer A, C phase GIL tubular bus is carried out as follows:

1. putting down two lifting belts hooked on large and small hooks of a crane along two sides of an upper-layer A or C-phase GIL horizontal section tubular bus, and respectively wrapping the lifting belts on the connecting flange side of an A or C-phase inner-layer GIL vertical tubular bus by using a tool U-shaped ring;

2. tightening the hanging strips, removing the flange connecting bolts, and decomposing the horizontal and vertical section tubular buses;

3. and after the crane is commanded to slowly fall down and the hanging strip of the inner side hook is completely loosened, the hanging strip on the outer side for the hanging strip on the inner side is removed, and the vertical tubular bus of the phase A or the phase C inner layer GIL is hung to the open position and is adjusted from the vertical state to the horizontal state to be laid down.

Further, in the step (2), the ultrahigh and overlong vertically overlapped part of the inner-layer intermediate phase GIL tubular busbar is carried out according to the following steps:

1. tightening the hanging strips, removing the flange connecting bolts, decomposing the horizontal and vertical section tubular buses, and putting the vertical section tubular buses wearing the transport seal plates on the ground for transition;

2. a hanging belt hooked on a big hook of a crane is put down along the outer side of the upper GIL horizontal section tubular bus of the phase A or the phase C, and is also wrapped on a connecting flange of the middle inner GIL vertical tubular bus by a tool U-shaped ring;

3. commanding the big and small hooks of the crane to be matched with each other and simultaneously loosening and tightening, and gradually displacing the tubular bus of the vertical section of the inner layer GIL to the outer side of the side phase GIL tubular bus by using a relative hoisting method;

4. and commanding the crane to slowly fall down the small hook until the small hook is completely loosened, dismantling the small hook lifting appliance, and lifting the B-phase inner layer GIL vertical tubular bus to an open position to be adjusted from a vertical state to a horizontal state.

Compared with the prior art, the invention has the following beneficial effects:

(1) the invention only needs to power off the lower GIL equipment to be overhauled, does not need to enlarge the power off range, and improves the power supply reliability of the system.

(2) The invention increases the output load.

(3) The invention has small potential safety hazard, less safety risk, controllable and controllable control, and less cross of working faces, thereby ensuring the safe and civilized construction appearance.

(4) The time consumed by continuous work is short, and the work efficiency is high.

(5) The limit of insufficient safety distance is small, and the working efficiency is improved.

Drawings

FIG. 1 is a schematic structural diagram of pipes of ACF3 (lower layer) and ACF4 (upper layer) of 500kVGIL tubular bus bar in the present invention;

fig. 2 is a schematic structural view of an SF6 gas processing auxiliary device in the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of examples of the present invention, and not all examples. All other embodiments, which can be obtained by a person skilled in the art without inventive effort based on the embodiments of the present invention, are within the scope of the present invention.

The method for overhauling the 500kV lower GIL tubular bus under the condition of no accompanying shutdown comprises the following steps:

step (1), gas management of GIL equipment:

and (3) vacuumizing a gas cylinder (gas tank), recovering gas in the gas chamber to half pressure, removing a conductor between the GIL and the GIS to connect a transition gas chamber connecting pipe, recovering residual gas in the gas chamber, uncovering to recover residual gas, purifying the gas, vacuumizing the gas cylinder (gas tank), and purifying the purified gas pressure cylinder by using an SF6 gas treatment auxiliary device. SF6 gas is usually stored in 50 kg units in steel cylinders weighing 50 kg, making a total weight of more than 100 kg. The number of SF6 gases in a 500kV voltage class transformer substation, a converter station, a switch station and the like is large, and the number of gas cylinders is also inevitably large. In order to better manage and control the gas, important information such as 'state, gas weight, time, person in charge' and the like is marked on an SF6 gas (gas cylinder) state signboard.

The specific operation is as follows:

1.1 evacuation of gas cylinder

Before the gas cylinder is used, the gas cylinder needs to be vacuumized, and whether accessories such as valves and the like are intact or not needs to be checked during vacuumizing. When the vacuum degree reaches 5Pa, the vacuum degree needs to be pumped for 10 minutes; then, the system is shut down. Finally, important information such as state, gas weight, time, responsible person and the like is filled in the SF6 gas (gas cylinder) state signboard on the gas cylinder carefully.

1.2 recovering gas in the gas chamber to half pressure, removing the conductor and connecting the transition gas chamber connecting pipe

The gas density relays and matched valves of the upper and lower layers of GIL tubular bus gas monitoring systems are all fixed on the steel support pillars in a centralized manner. High-pressure gas is led down from the high altitude through a metal high-pressure pipeline. When handling the work ticket, it is clear in the security measures that: and winding and sticking red forbidden marks on adjacent high-voltage valves (interfaces) which are in live-line operation. Particularly, when only a certain air chamber of a certain outgoing line is overhauled, confusion is easy to happen, and the effective method is more necessary to be popularized and applied.

In the initial stage of gas recovery, the flow can be controlled through a valve to utilize the pressure difference formed by high vacuum in the gas cylinder and high pressure in the gas chamber, the gas cylinder is directly inflated from the gas chamber to the gas cylinder, and in the process, the gas cylinder is placed on a platform scale to monitor the weight of the gas in real time.

In order to meet the requirements of extension, test and the like of GIL and GIS equipment, a conductor is usually arranged between the GIL and the GIS equipment to connect an independent transition gas chamber, the gas chamber is small and single in function, and no independent monitoring equipment is usually used for managing and monitoring gas from an adjacent GIL gas chamber by using a communicating pipeline.

Before the air chambers are vacuumized, in order to prevent the basin-stop insulator between the air chambers from being damaged under the action of the bidirectional high pressure difference formed under the rated air pressure, all manufacturers require that the adjacent air chambers can be vacuumized after half pressure reduction. When the gas in the GIL and the transition gas chamber is recovered to be half pressure, the machine is stopped firstly, and a high-pressure pipeline with a conductor communicated with the transition gas chamber is dismantled.

1.3 recovery of residual gas from the gas cell

And after the high-pressure pipeline communicated with the transition gas chamber is removed, the residual gas in the GIL gas chamber can be continuously recovered. The GIL pipeline long air chamber has a large amount of air, moreover, a plurality of GIL air chamber interfaces are positioned at the waist of the tubular bus, and a plurality of gases are actually still in the air chamber when the density relay displays zero pressure. The suction of surplus gas can be performed for a long time with an SF6 gas processing plant with an oil-free suction pump unit.

1.4 uncovering and recovering residual gas

After the gas insulation equipment is opened, a lot of gas escapes from the lower part of the pipe opening, which is caused by heavy SF6 gas. Actually, clean residual gas is not recovered, in order to reduce loss and protect the environment, a pipeline bound by double-layer plastic cloth is fixed at the pipe opening of the tubular bus, the other end of the pipeline is introduced into a plastic cylinder, and then a high-pressure pipeline of the SF6 gas treatment device is extended into the plastic cylinder to start up the machine and recover the residual gas. The recovered gas has high air content, and can be purified and purified by an SF6 gas treatment device subsequently, so that unnecessary loss and greenhouse gas emission can be effectively reduced.

1.5 post-purification gas bottle

Generally, SF6 gas treatment devices are effective for moisture, particulate matter impurities, and the like, but are less sensitive to air. The air content exceeding standard needs to be treated by equipment with purification function. And (4) filling the purified and purified gas into the air bottle which is vacuumized again after the purified and purified gas is qualified in the test, and monitoring the weight in real time by using a platform scale during the filling.

Step (2), the 500kV lower GIL tubular bus is overhauled safely and efficiently under the condition of no accompanying shutdown

2.1 hoisting

Before dismantling, the bellows expansion joint in the running state needs to be adjusted to the transportation state, namely, a transportation bolt fixed on a flange on one side of the bellows expansion joint is loosened and penetrates into a connecting flange of a tubular bus on the other side, and then nuts on the transportation bolts of the connecting flanges on the two sides of the bellows expansion joint are screwed. And the bellows expansion joint is not stressed in the hoisting process.

Before the installation and the operation are finished, the transportation bolt needs to be loosened and returned to be fixed on a flange on one side of the bellows expansion joint, the distance from the end head of the transportation bolt to the inner side of the other flange surface needs to be larger than the length of the bellows expansion gap, and the bellows expansion joint can normally work. 2.2500 kVGIL tubular bus bar typical difficult position is demolishd or is repackaged

The present embodiment is directed to ACF3 (lower) and ACF4 (upper) pipelines.

2.21 ground overlapped part lower layer B phase (intermediate phase) GIL tubular bus

After the recovery of the gas in the relevant gas chamber SF 6. When the bamboo fiber board is dismantled, firstly, a high-strength bamboo fiber board is paved on the ground of the common mark stone of the conveying path. Then, the two rotary hydraulic support transfer trucks arranged on the high-strength bamboo fiber board are conveyed to the lower part of the bus to jack up the tubular bus with the connecting bolt removed. The removed bus-section is then moved to the left until the contacts on the right are separated.

The suspended lower-layer GIL tubular bus can move randomly in the positive and negative directions of the three-dimensional space on the rotary hydraulic support transfer trolley, so that the flange with the largest diameter on the right side is prevented from impacting the steel support.

And pulling out the right side of the bus section outwards, sealing the flange surface with plastic cloth for dust prevention, and transporting the bus section out of a disassembling site by using a crane.

Before the flange is disassembled, except for marking the name on the section of the tubular bus, an S-shaped mark needs to be drawn on the connecting flange. In order to reduce errors and avoid the difficulty caused by error accumulation and overproof errors for the assembly, two positioning pins are required to be symmetrically inserted into the connecting flange to be referred to the S-shaped mark on the connecting flange for recovery during the assembly.

During installation, after the tubular bus is in place, the dustproof plastic cloth needs to be dismantled and transported, the sealing surface needs to be cleaned, the sealing ring needs to be placed, after no remnants are left in the air chamber through photo confirmation, the flange hole of the tubular bus moves slowly along the positioning pin so that the conductor is inserted firstly, then the two flange surfaces are tightly attached through the light tightening clamp, then 4 cross bolts are inserted into the flange hole and fastened, and finally, the remaining bolts are inserted into the flange hole and fastened according to rules.

2.22 multiple lower layer GIL tubular bus with insufficient safety distance with adjacent charged bodies and high-altitude overlapping part

And calculating the number and the positions of wheel disc fast-assembling bearing scaffolds (supporting and releasing rotary hydraulic support transfer vehicles) to be erected according to parameters such as the requirement of the safety distance, the site condition, the position of the grounding block on the tubular bus, the length of the tubular bus to be displaced and the like.

After high-strength bamboo fiber boards are laid on the surface of the centimeter stone, a supporting platform is built by using a wheel disc quick-mounting bearing scaffold. Then, after leveling and aligning the scaffold by using an adjusting base sleeved on the upright post of the supporting platform, the inclined supporting end support is fastened by using a steel pipe fastener. And then laying 4000 x 300 x 50mm long wood boards and high-strength bamboo fiber boards on the top of the supporting platform in advance. And finally, erecting a skirting railing by using a steel pipe fastener at about 180 mm above the top of the supporting platform.

The lower-layer GIL tubular bus is safely dismantled or recovered by jacking and supporting the GIL tubular bus through a plurality of rotary hydraulic support transfer trolleys (more than two rotary hydraulic support transfer trolleys are arranged on the wheel disc quick-mounting bearing scaffold and are determined according to the site condition and the length of the tubular bus to be displaced), horizontally displacing the plurality of sections of the lower-layer GIL tubular buses to a safe region far away from a charged body on the hydraulic support transfer trolleys.

During installation, the first section of tubular busbar needs to be hung on the rotary hydraulic support transfer trolley in a safe area and firstly moves to the position below the high-altitude overlapped upper-layer live-line operation tubular busbar. And then, the second section of tubular busbar is connected and then displaced, so that the plurality of sections of tubular busbars are displaced to the target position to be connected and fastened.

2.23 vertical corrugated pipe 17 of lower layer B phase (middle phase) GIL tubular bus passing through the high-altitude overlapped part of the road with insufficient safety distance with the adjacent charged body, as shown in figure 1.

500kV crosses the highway and overlaps the big weight in the high altitude overlap partial GIL cast bus span of upper and lower floor, and the horizontal segment side is supported with two stand steelframes, except that the wedge between two stands and B looks cross arm for bolted connection, all the other A, C looks cross arms are the whole work piece of one shot forming for satisfying the maintenance demand and resisting natural disasters. The square iron tower is used as a support part on the sides of the GIL tubular bus, the tee joint and the vertical corrugated pipe expansion joint of the overhead overlapping part of the upper layer and the lower layer of the highway.

Because the safe distance with adjacent electrified body is not enough (need > 8.5 meters), take perpendicular bellows expansion joint moreover and can't pass through the square iron tower hole, machinery such as crane also can't use, so can only take the manual mode to dismantle perpendicular bellows expansion joint after dismantling the horizontal segment tubular bus and the conductor that are connected with perpendicular bellows earlier, concrete flow is as follows:

using two 200X 100X delta 8mm steel plates, performing lofting and drilling on each 200mm side of each steel plate by illuminating three continuous bolt holes (the whole circumference is divided into 24 holes) of a circumferential flange of the tubular bus tee, measuring the inner side sizes of two flange surfaces of the tubular bus tee, blanking two flat steels with 100X delta 8mm, arranging and welding the two flat steels in a T shape at the ends of the non-drilled sides of the two steel plates with 200X 100X delta 8mm, and manufacturing the lifting tool.

And fixing a lifting and hoisting tool on the top of the lower-layer GIL tubular busbar tee joint by using six flange connecting bolts, winding two nylon lifting belts on the tool, and respectively hooking the two chain hoists on lifting belt lifting rings.

Two nylon hanging belts are respectively wound on a square flange below a vertical corrugated pipe expansion joint of the tubular bus, and then the two hanging belt hanging rings are respectively hooked on the other ends of the two chain hoists.

And tightening the two chain hoists, and removing the lower tee joint and the vertical corrugated pipe telescopic joint flange connecting bolt.

2.24 passing through the lower layer B phase (middle phase) GIL tubular bus (with upper tee) 19 of the high-altitude overlapped part of the road, as shown in figure 1.

After a vertical corrugated pipe expansion joint on the outer side of a square iron tower and a horizontal section tubular bus on the outer side of a double-upright post are removed from a B-phase (middle-phase) GIL tubular bus on the lower layer of the high-altitude overlapped part of the passing highway, the GIL tubular bus on the lower layer of the passing highway can be removed, and the method specifically comprises the following steps:

the upper and lower hanging rods are utilized to prop open the connecting hanging strips to form a rectangular square frame, so that the B-phase upper layer tubular bus is arranged in the rectangular square frame and is respectively and annularly wrapped on the lower layer B-phase (middle phase) GIL tubular bus (with an upper tee joint). The method comprises the following specific steps:

2.241 after the horizontal hoisting is tried, the crane is instructed to hoist the tubular busbar slowly by about 50 mm. 1 high-strength bamboo fiber board of about 2000 x 800 x 10mm is plugged between the tubular bus fixing plate and the square iron tower fixing base.

2.242 directs the crane to adjust and slowly hang the lower GIL tubular busbar (with tee) of the phase B (middle phase) to pass through the square iron tower hole.

2.243 detaching the cross arm and the inclined iron between the double upright posts of the lower GIL tubular busbar of the lower layer B phase (middle phase) in a short time.

2.244 directs the crane to slowly and vertically hoist the lower layer B phase (middle phase) lower layer GIL tubular busbar onto the ground V-shaped transportation frame, and the special transportation closing plate for the tee joint is installed on the flange surface of the tee joint. During hoisting, the lifting appliance vertically moves up and down in a gap between the AB and BC phases of the upper-layer GIL tubular bus, and always keeps a preset distance from the upper-layer GIL tubular bus in live operation, so that the whole process ensures that the upper-layer GIL live tubular bus cannot be subjected to extra stress, live operation equipment can reliably operate, potential safety hazards of the equipment and the like caused by displacement due to stress cannot be generated. The whole hoisting process ensures that the conductor extending out of the lower plane of the flange surface of the tubular bus tee joint cannot be collided and damaged.

2.25 passing through the high overlapping part of the highway the lower layer A, C phase GIL tubular busbar (with tee and vertical bellows expansion joint) 18 is shown in figure 1.

The lower layer A, C phase GIL tubular busbar square iron tower and the outer sides of the double-upright-column support frames at the high-altitude overlapped part of the over-highway have no barriers, can be integrally lifted with the tee joint and the vertical corrugated pipe, and needs to be hoisted by a truck crane or two cranes with large and small hooks.

Because the lower-layer side-phase (A-phase or C-phase) steel pillar supporting cross arm cannot be detached, the lower-layer GIL side-phase (A-phase or C-phase) tubular bus is detached or put in place by using a relative hoisting method according to the principle of extending acting force and reacting force. And the safe operation of the upper GIL live tubular bus is ensured. The specific process is as follows:

when the hanger is detached, firstly, an assembly hook of the antiskid lifting appliance is hung on a hook block of a crane, the lifting belt at the inner side penetrates through the gap of the upper middle phase (AB or BC phase) GIL tubular bus, and the antiskid lifting belt is respectively and annularly wrapped on the side phase GIL tubular bus; and (3) putting down a pair of lifting belts hung on the small hooks along the outer side of the side phase tubular busbar, and wrapping the lifting belts on the tubular busbar by using a tool U-shaped ring.

And a large hook of the command crane is slowly lifted to the upper surface of the lower layer GIL tubular bus and almost touches the lower surface of the steel bracket cross arm of the upper layer tubular bus. And then commanding the crane to loosen the anti-skidding lifting appliance on the big hook while tightening the hanging strip of the small hook, and gradually displacing the lower-layer GIL tubular bus to the outer side of the steel support until the big hook is completely loosened and all loads are transferred to the small hook, and the lower-layer GIL tubular bus completely leaves the steel support supporting cross arm. And then the lower GIL tubular busbar of the side phase is hoisted to the ground with the tee joint and the vertical corrugated pipe for further dismantling.

When the anti-skid hanger is installed, the anti-skid hanger is firstly hooked on a hook of a crane; then, a pair of hanging belts and a tool U-shaped annular pocket tubular bus are hooked on the small hook; then, hoisting the lower-layer GIL tubular bus of the side phase to the side of a set position by using a small hook, enabling a sling at the inner side of the sling which is hooked on a large hook of a crane to penetrate through the gap of the middle-layer (AB or BC phase) GIL tubular bus of the upper-layer side, and respectively looping and wrapping the anti-skidding sling on the side-phase GIL tubular bus; and finally, commanding the big hook and the small hook of the crane to be matched, loosening and tightening, and gradually displacing the lower layer GIL tubular busbar to the position below the upper layer GIL tubular busbar by using a relative hoisting method. The whole process is under the principle of 'acting force and reacting force', the resultant force borne by the GIL tubular busbar on the upper layer of the side phase approaches to zero, and the safe operation of the GIL tubular busbar on the upper layer A or C phase is ensured. The live-line operation equipment can reliably operate, and potential safety hazards of the equipment and the like caused by displacement due to stress can be avoided.

2.26 ultra-high overlength vertically overlapping partially inner layer A, C phase GIL tubular busbar 20, as shown in fig. 1.

In order to guarantee the use function of structures such as a converter transformer overhaul factory building, the GIL tubular buses need to be arranged in a staggered manner, so that a plurality of ultrahigh and overlong tubular buses are vertically overlapped. And (4) after the horizontal section tubular busbar connected with the vertical overlapped tubular busbar is removed. The concrete flow of hoisting the inner layer A, C phase GIL tubular bus vertically overlapped is as follows:

2.261 two hanging belts hooked on the big and small hooks of the crane are put down along the two sides of the upper layer A or C phase GIL horizontal section tubular bus, and are respectively wrapped at the connecting flange sides of the A or C phase inner layer GIL vertical tubular bus by a tool U-shaped ring.

2.262 commanding the crane big and small hooks to tighten the hanging strip, dismantling the flange connecting bolt, and decomposing the horizontal and vertical section tubular bus.

2.263 the crane is directed to slowly fall down and the inner hook hanging strip is completely loosened, the inner hanging strip is removed, and the outer hanging strip is used to hang the A or C phase inner layer GIL vertical tubular bus to the open position and is adjusted from the vertical state to the horizontal state to be laid down.

2.27 super-high super-long vertical overlapped part of the inner layer B phase GIL tubular busbar 21 as shown in figure 1.

The horizontal section tubular busbar connected with the inner layer B-phase GIL vertical overlapped tubular busbar is removed, after the inner layer A, C-phase GIL vertical overlapped tubular busbar is also removed, the inner layer B-phase GIL tubular busbar can extend the principle of 'acting force and reacting force', and is hoisted by using a 'relative hoisting method', and the specific flow is as follows:

when the hanger is detached, the anti-skid hanging strip is firstly hooked on a small hook of a crane, the hanger is put down along two sides of the upper layer B-phase GIL horizontal section tubular bus, and the U-shaped rings of the tool are symmetrically arranged at 180 degrees and are respectively and annularly wrapped on two sides of a connecting flange of the B-phase inner layer GIL vertical tubular bus.

2.271 commands the crane hook to tighten the hanging belt, removes the flange connecting bolt, decomposes the horizontal and vertical section tubular bus, and puts the vertical section tubular bus wearing the transportation sealing plate on the ground for transition.

2.272 the sling hooked on the hook of the crane is put down along the outer side of the upper GIL horizontal section tubular bus of the phase A or the phase C, and is also wrapped on the connecting flange of the vertical tubular bus of the inner GIL of the phase B by a tool U-shaped ring.

2.273 the crane hook is controlled to be loose and tight, and the inner layer GIL vertical section tubular busbar is gradually moved to the outer side of the side phase GIL tubular busbar by using the relative hoisting method, as shown in the figure.

2.274 commanding the crane to slowly drop the small hook until the small hook is completely loosened, dismantling the small hook lifting appliance, and lifting the B-phase inner layer GIL vertical tubular bus to the open position to be adjusted from the vertical state to the horizontal state.

Step (3) recovering GIL equipment air chamber management

The installation of the SF6 gas insulated equipment needs to be carried out in a clean environment with the humidity not more than 70%.

The air chamber management process for installing the GIL equipment comprises the following steps: the method comprises the steps of positioning the tubular bus from the GIS interface side in sequence when the tubular bus is dismantled, cleaning a sealing surface on the ground, temporarily sealing, hoisting, cleaning again, confirming that no remnants are left by photographing, butting (if the humidity exceeds or is close to 70 percent, dry air with the dew point higher than-40 ℃ is filled into an air chamber), testing the loop resistance, replacing an adsorbent, vacuumizing, detecting leakage under negative pressure, inflating (using an SF6 gas processing device to break vacuum at the negative pressure stage), statically discharging, adjusting the pressure, and performing a sampling test, detecting leakage and injecting glue.

The method comprises the following specific steps:

3.1 the tubular busbars are positioned in sequence from the GIS interface side when being dismantled

Generally, the recovery installation is carried out by starting from the GIS side and advancing to the outgoing line high-voltage bushing side. Before recovery, the tubular bus is orderly organized according to the installation sequence and is in place in advance, and after a sealing surface is cleaned on the ground, a sealing ring is installed and then sealed by double-layer plastic cloth.

3.2 hoisting-cleaning again, taking a picture to confirm no remnants

And (4) hanging the butt joint position, leaving an operation space to carefully clean the two sealing surfaces, placing the name of the two sections of tubular buses of the butt joint surface in the air chamber, taking a picture, reserving the picture for future reference, taking out the mark, confirming again that no object is left, and carrying out butt joint.

3.3 testing the resistance of the loop after butting according to the S-shaped mark

The maintenance is to perform maintenance on the equipment which is installed and operated for a period of time or has a fault, the two connecting surfaces of the equipment are mutually adaptive and matched after the equipment is operated for a long time to achieve the best effect, and the phenomenon that air leakage does not exist can be explained. Therefore, in order to restore the original position, an "S" shaped mark is drawn on the two connecting surfaces before the removal. During re-assembly, two positioning pins with the tolerance matching of only 0.2 mm need to be symmetrically penetrated in the waist part of the tubular busbar connecting flange, the two sections of tubular busbar connecting surfaces are tightly attached by light tightening pliers after a conductor is controlled to be accurately inserted, 4 bolts arranged in a cross shape are penetrated into opposite angles after the connection surfaces are restored by contrasting the positions of the S-shaped marks, the two positioning pins are easily pulled out after the cross opposite angle bolts are fastened by matching two persons, and the remaining bolts are penetrated and fastened circularly. After the butt joint is finished according to relevant regulations, the subsequent tubular bus can be continuously installed only if the loop resistance test is carried out and qualified.

If the environmental humidity is larger than or close to 70 percent or the dust and smoke in the working environment exceed the standard are more, the dry air generator or the air bottle is used for continuously filling the dry air with the dew point of more than minus 40 ℃ into the air chamber, so that the moisture and the impurities in the atmosphere are prevented from being mixed into the air chamber.

3.4 Replacing the adsorbent

The GIL tubular busbar adsorbent is usually arranged on a terminal cover plate of a corner turning tubular busbar, the quantity of the GIL tubular busbar adsorbent is determined according to the length of the tubular busbar, and the adsorbent is required to be completely replaced within 2 hours, closed and vacuumized.

3.5 evacuation, leak detection by negative pressure

Before each air chamber is vacuumized, the rubber hose needs to be vacuumized to check whether air leaks or not, and if the air leaks, a new rubber hose is replaced.

After the vacuum of each air chamber is vacuumized to be below 67Pa (1 torr), the air chamber is continuously vacuumized for more than 1 hour, then the air chamber is stopped and stood for more than 5 hours, the previous vacuum value is subtracted from the vacuum value measured again, and the recovery value of the vacuum degree is not more than 67 Pa. Then the machine is started again and the air can be inflated after 30min of pumping.

3.6 aeration

The inflation operation must be performed in sunny weather. Before inflation, the detected SF6 gas moisture and decomposition product content are qualified, and then the gas can be filled into GIS equipment. The negative pressure stage suggests using SF6 gas processing equipment to purify the qualified gas for vacuum relief. Because the gas volume of the long gas chamber with the length of the GIL tubular bus is large, the capacity of the purification and purification tank of the SF6 gas processing device is limited, and the speed can not meet the requirement. The air chamber can only be inflated by a small air bottle through a pressure reducing valve. Before the pipeline connection between the gas cylinder pressure reducing valve and the gas chamber valve is replaced, the valve is opened to continuously purge and dry for 1min under positive pressure, and the connection is completed under the working condition of micro positive pressure. The velocity of flow should not be too fast when aerifing, and the gas freezes easily in the too fast bottle, produces the drop of water easily on the table connects the pipeline, for preventing that moisture from invading the air current, can wrap the moisture absorption with the better cotton of hydroscopicity ability in joint department, simultaneously, heats with the heater bottom the gas cylinder.

The SF6 gas treatment adopts an SF6 gas treatment auxiliary device.

As shown in fig. 2, the SF6 gas processing auxiliary device comprises a gas cavity 4, 10 SF6 gas cylinders 15 connected with the gas cavity 4, the SF6 gas cylinders 15 are symmetrically distributed on two sides of the gas cavity 4, a valve 2 of a body of the SF6 gas cylinder 15 is communicated with the gas cavity 4 through a DN10 high-pressure valve 1, one side of one end of the gas cavity 4 is connected with an SF6 gas processing device 9 through a first DN20 high-pressure valve 8, the SF6 gas processing device 9 is connected with one end of a four-way joint 14 through a second DN20 high-pressure valve 8, and the other end of the four-way joint 14 is communicated with the other side of one end of the gas cavity 4 through a third DN20 high; one end of the remaining two ends of the four-way joint 14 is connected with a control system of an air chamber 10 of SF6 electrical equipment, the other end of the four-way joint is connected with one end of a three-way joint 7 through a DN10 high-pressure valve 1, the second end of the three-way joint 7 is connected with a pressure reducing valve 5, and the pressure reducing valve 5 is connected with an air chamber 4 through a DN10 high-pressure valve 1.

The third end of the three-way joint 7 is connected with a high-precision pressure gauge 6. One end of the air cavity 4 is also provided with a standby valve 3, and the standby valve 3 is connected with the air valve 4 through a stainless steel high-pressure steel pipe 11. The standby valve 3 adopts a DN10 high-pressure valve and is always in a closed state.

DN10 high-pressure valve 1 is connected with air cavity 4 through stainless steel high-pressure steel tube 11, SF6 gas cylinder body valve 2 is connected with DN10 high-pressure valve 1 through polytetrafluoroethylene transparent colorful high-pressure tube 12.

In a bypass at one side of the air chamber, a DN10 high-pressure valve 1, a pressure reducing valve 5, a three-way joint 7 and a four-way joint 14 are all connected through a stainless steel high-pressure pipe 11, and the four-way joint 14 is connected with a control system of an air chamber 10 of SF6 electrical equipment through a steel cage protection pipe 13.

The first DN20 high-pressure valve 8 is connected with the SF6 gas processing device 9 through a steel cage protection pipe 13, the SF6 gas processing device 9 is connected with the second DN20 high-pressure valve 8 through the steel cage protection pipe 13, the second DN20 high-pressure valve 8 is connected with the four-way joint 14 through a stainless steel high-pressure pipe 13, and the other end of the four-way joint 14 is connected with the third DN20 high-pressure valve 8 through a stainless steel high-pressure pipe 11. The front end of the air cavity is connected with a high-precision vacuum pressure gauge 16 through a high-pressure valve.

The gas chamber of the stainless steel material of the SF6 gas treatment auxiliary device of this embodiment is welded with 15 stainless steel pipes connected with high pressure valves. The high-pressure valve is connected to the stainless steel pipeline interface.

When gas is recovered from the SF6 gas equipment gas chamber into the gas cylinder by the SF6 gas processing device, the operation is as follows: and respectively connecting 10 high-pressure air pipes to 10 steel gas cylinder interfaces, and closing high-pressure valves at two sides of each monitoring unit (a monitoring unit is composed of a pressure reducing valve, a high-precision pressure gauge and a connected pipeline and the high-pressure valves). The high-pressure gas pipe is respectively connected to an SF6 gas equipment gas chamber and an SF6 gas processing device interface. And (3) placing the first air bottle on the weighbridge scale, opening the high-pressure valves at two sides of the first air bottle, and closing the high-pressure valves at two sides of the other 9 air bottles. And opening a valve of a gas chamber of SF6 gas equipment, starting an SF6 gas processing device, and slowly opening a high-pressure valve of an SF6 gas processing device. The high-pressure valves on two sides of the first steel gas cylinder are closed when the weight of gas in the cylinder is monitored to 50 kilograms in real time through the weighbridge, meanwhile, the high-pressure valves on two sides of the high-pressure pipeline of the second steel gas cylinder are opened, the weighbridge is placed under the second steel gas cylinder to monitor the weight of the gas, and the process is repeated.

When the gas treatment device through SF6 is used for vacuumizing a gas cylinder and a high-pressure pipeline, the operation is as follows: and respectively connecting 10 high-pressure air pipes to 10 steel gas cylinder connectors. The high pressure gas lines were connected to the SF6 plant (gas cell) and SF6 gas processing plant interfaces, respectively. All high pressure valves connected to the air cavity and 10 air bottles were opened. The high pressure valve is opened and the high precision vacuum pressure gauge 16 detects the pressure.

And (3) closing valves of SF6 equipment (gas chamber), starting a vacuum pump of an SF6 gas processing device, vacuumizing to 5Pa, continuously vacuumizing for 10min, closing all the valves, and stopping the machine. And the process is circulated.

When qualified gas is filled into the SF6 equipment (gas chamber) from the gas cylinder, the negative pressure (high vacuum) stage is operated as follows: and respectively connecting 10 high-pressure air pipes to 10 steel gas cylinder connectors. The high-pressure air pipes on the air chamber are respectively connected to an SF6 gas processing device and an SF6 equipment (air chamber) interface. And closing the high-pressure valves at the two sides of the other 9 air bottles, and opening the high-pressure valves at the two sides connected with the first air bottle. And (3) opening high-pressure valves at two sides of the monitoring unit, starting the SF6 gas processing device, opening valves of SF6 equipment (gas chamber), slowly opening valves of the reducing valve, and repeating the steps until the pressure in the gas chamber reaches micro-positive pressure. The operation of the chamber from slight positive pressure (above 0 pressure) to rated pressure is as follows: and closing the high-pressure valves at two sides of the monitoring unit, opening the high-pressure valves at two sides of the multi-cylinder steel gas cylinder, monitoring the pressure by using a gas chamber body density relay, and opening the monitoring unit to fill the gas into the gas chamber one by one until the rated pressure is reached to close the valves, wherein the process is repeated.

The SF6 gas processing device is a special auxiliary device for SF6 gas processing, which integrates the functions of vacuumizing, recovering, aerating, purifying and the like. Is an existing mature product and is specially used for installation, maintenance and other work of SF6 gas equipment.

The layout of the SF6 gas processing auxiliary device of the present embodiment is divided into three devices: the upper platform comprises an air cavity, a high-pressure pipeline interface, a high-pressure valve, a monitoring unit and the like; the middle platform is a coil pipe fixing frame, a special wrench jack and a platform scale; the lower platform is provided with a movable wheel; a frame, a lifting ring, dustproof and rainproof protection and the like are arranged outside the device.

The air cavity of the device is a hollow closed clean cavity, and stainless steel pipes connected with the outside are all welded. The stainless steel high-pressure valves of 10 DN10 on the device are respectively connected with 10 SF6 gas cylinders and the gas cavity of the device through 10 rubber hoses, and the state regulation and control are carried out through the stainless steel high-pressure valves of 10 DN10 and the high-pressure valves carried by the 10 gas cylinders.

The gas cavity is also respectively provided with 3 stainless steel high-pressure valves of DN20, one is a four-way valve connected with the gas cavity of the SF6 gas processing auxiliary device, the other is a four-way valve connected with the SF6 gas processing device, and the other is a gas cavity of the SF6 gas processing auxiliary device connected with the SF6 gas processing device.

The pressure reducing valve and the T-connection lead-out are connected with a stainless steel high-pressure valve of DN10 at two ends of a tee joint of the high-precision pressure gauge respectively, the tee joint connected with the high-precision pressure gauge is connected with a reducing cross through the DN10 stainless steel high-pressure valve, the other three sides of the reducing cross are connected with an SF6 electrical equipment air chamber, an SF6 gas processing device and an SF6 gas processing auxiliary device air chamber respectively, and for convenience of function control, DN20 stainless steel high-pressure valves are additionally arranged on branch circuits connected with the SF6 gas processing device and the SF6 gas processing auxiliary device air chambers respectively. The switching monitoring unit is realized by changing the states of the valves on the two sides of the branch pipeline of the monitoring unit. And comparing the accurate pressure in the monitoring air chamber by using a high-precision pressure gauge.

The SF6 gas treatment auxiliary device is mainly developed aiming at saving time, reducing gas discharge, improving gas quality control level and the like under the working conditions of more small gas cylinders, larger quantity of gas to be treated, higher frequency of dismounting and mounting of a high-pressure pipeline and the like. The SF6 gas processing auxiliary device takes 10 gas cylinders as a group, and can be matched with the gas cylinder pipeline for vacuumizing, positive pressure blowing, filling the recycled gas into the gas cylinder and filling the gas into a gas chamber from the gas cylinder after one-time connection. The time for repeatedly disassembling and assembling the high-pressure pipeline joint is centralized to be completed at the same time, the operation time is shortened, the operation frequency is reduced, the emission of trace gas is also reduced, and particularly, the risk of gas quality reduction caused by replacing a gas cylinder is avoided.

In the process of vacuumizing and inflating each air chamber of the GIL equipment, in order to avoid quality defects caused by the stress of the basin-type insulator, the inflation operation is strictly executed according to the standard requirement that the pressure difference of the adjacent air chambers is not more than 0.3 MPa. Filling SF6 gas at 0.2-0.3 MPa, standing for 12 hours to detect the moisture content and the content of decomposed substances in the gas chamber, and continuing to supplement the gas to the rated pressure after the gas is qualified.

When an SF6 density relay and a high-pressure pipeline are assembled, the SF6 which is clean and qualified is used for positive pressure purging for 1min, and the inside of an SF6 pipeline is dry and free of residual impurities.

3.7 standing, adjusting pressure, detecting leakage, testing and injecting glue.

And (4) sampling and detecting the contents of water and decomposition products after 24 hours of air filling and static discharge, and determining the contents of the water and the decomposition products to be qualified, performing pressure resistance and partial discharge tests after leakage detection, and performing glue injection and the like after the contents are qualified.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. A method for overhauling a lower 500kVGIL tubular bus without accompanying shutdown condition is characterized in that: the method comprises the following steps:

step (1), gas management of GIL equipment:

vacuumizing the gas cylinder by using an SF6 gas processing auxiliary device, recovering the gas in a GIL gas chamber and a transition gas chamber between the GIL and a GIS to half pressure, then removing a conductor connecting pipe between the GIL and the GIS and connecting the transition gas chamber, recovering the residual gas in the GIL gas chamber, opening a cover to recover the residual gas, then purifying the gas, vacuumizing the gas cylinder, and pressing the purified gas into the cylinder;

step (3) recovering GIL equipment air chamber management

The method comprises the steps of sequentially placing tubular buses from the GIS interface side when the tubular buses are dismantled, cleaning a sealing surface on the ground, then temporarily sealing, hoisting, cleaning again after hoisting, confirming that no remnants exist, then butting, filling dry air with the dew point higher than-40 ℃ into an air chamber if the humidity exceeds or is close to 70%, then testing loop resistance, replacing an adsorbent, then vacuumizing, detecting the leakage under negative pressure, breaking the vacuum by using an SF6 gas processing auxiliary device in the negative pressure stage, then inflating and statically releasing, adjusting the pressure, performing a sampling test, and finally performing leakage detection and glue injection.

2. The method of servicing a lower 500kVGIL tubular busbar without accompanying downtime of claim 1, wherein: in the step (1), the gas treatment auxiliary device in the gas management of the GIL equipment comprises a gas cavity and a plurality of SF6 gas cylinders connected with the gas cavity, the SF6 gas cylinders are distributed on two sides of the gas cavity, valves of a SF6 gas cylinder body are communicated with the gas cavity through DN10 high-pressure valves, one side of one end of the gas cavity is connected with the SF6 gas treatment device through a first DN20 high-pressure valve, the SF6 gas treatment device is connected with one end of a four-way joint through a second DN20 high-pressure valve, and the other end of the four-way joint is communicated with the other side of one end of the gas cavity through a third DN 20; one of the other two ends of the four-way joint is connected with a control system of an air chamber of SF6 electrical equipment, the other end of the four-way joint is connected with one end of the three-way joint through a DN10 high-pressure valve, the second end of the three-way joint is connected with a pressure reducing valve, and the pressure reducing valve is connected with the air chamber through a DN10 high-pressure valve.

3. The method of servicing a lower 500kVGIL tubular busbar without accompanying downtime of claim 1, wherein: in the step (1), the gas management of the GIL equipment comprises the following specific steps:

1.1 evacuation of the gas cylinder

High-pressure gas is led down from the high altitude through a high-pressure pipeline; in the initial stage of gas recovery, the flow is controlled by a valve, and the gas is directly charged into the gas cylinder from the gas chamber by utilizing the pressure difference formed by high vacuum in the gas cylinder and high pressure in the gas chamber;

1.3 recovery of residual gas from the gas cell

1.4 uncovering and recovering residual gas

1.5 post-purification gas bottle

4. The method of servicing a lower 500kVGIL tubular busbar without accompanying downtime of claim 1, wherein: in the step (2), when the lower-layer intermediate-phase GIL tubular busbar of the ground overlapped part is dismantled after the gas in the related gas chamber SF6 is recovered, firstly, a high-strength bamboo fiberboard is paved on the ground of the common mark stone of the conveying path; then, two rotary hydraulic support transfer trucks arranged on the high-strength bamboo fiber board are conveyed to the lower part of the bus to jack up and take off the tubular bus of the connecting bolt; moving the disassembled bus section to the left to separate the contacts at the right side; in the process, the suspended lower GIL tubular bus can freely move in the positive and negative directions of the three-dimensional space on the rotary hydraulic support transfer trolley, so that the flange with the largest diameter on the right side is prevented from impacting the steel support; pulling out the right side of the bus section outwards, sealing the flange surface for dust prevention, and transporting the bus section out of a disassembling site by using a crane; before the flange is disassembled, marking names on the corresponding section of the tubular bus, and drawing marks on the connecting flange;

during installation, after the tubular bus is in place, the dustproof plastic cloth for transportation, the sealing surface cleaning and the sealing ring placing are required to be dismantled, after the fact that no objects are left in the air chamber is confirmed, the flange hole of the tubular bus moves slowly along the positioning pin to enable the conductor to be inserted firstly, then the two flange surfaces are tightly attached through light tightening pliers, then 4 cross bolts are inserted into the flange hole and fastened, and finally the remaining bolts are inserted into the flange hole and fastened according to regulations.

5. The method of servicing a lower 500kVGIL tubular busbar without accompanying downtime of claim 1, wherein: in the step (2), for the multi-section lower-layer GIL tubular bus with insufficient safety distance with the adjacent charged body and high-altitude overlapping part, the number and the positions of a wheel disc fast-assembling bearing scaffold and a transfer trolley which need to be erected are calculated according to parameters; the parameters comprise the requirement of safe distance, the site condition, the position of a grounding block on the tubular bus and the length of the tubular bus to be displaced;

after laying high-strength bamboo fiber boards on the surface of the centimeter stone, firstly, quickly mounting a bearing scaffold by using a wheel disc to build a supporting platform; then, after leveling and aligning the scaffold by using an adjusting base sleeved on the upright post of the supporting platform, a steel pipe fastener is used for fastening an inclined supporting end support; pre-laying a wood board and a high-strength bamboo fiberboard on the top of the supporting platform; finally, erecting a skirting rail at a position of about 180 mm above the top of the supporting platform by using a steel pipe fastener; jacking up and supporting the GIL tubular bus by a plurality of rotary hydraulic support transfer trucks arranged on the wheel disc quick-mounting bearing scaffold, horizontally moving a plurality of sections of lower-layer GIL tubular buses to a safe region far away from a charged body on the hydraulic support transfer trucks, and safely dismantling the lower-layer GIL tubular buses;

6. The method of servicing a lower 500kVGIL tubular busbar without accompanying downtime of claim 1, wherein: in the step (2), for a lower-layer middle-phase GIL tubular bus vertical corrugated pipe which has insufficient safety distance with an adjacent charged body and passes through a highway high-altitude overlapping part, lofting and drilling holes by using two steel plates according to three continuous bolt holes of a tubular bus tee circumferential flange on the side of 200mm of each steel plate, measuring the inner side sizes of two flange surfaces of the tubular bus tee, blanking two steel plates by using flat steels, arranging and welding the two flat steels in a T shape at the end heads of the non-drilled sides of the two steel plates, and manufacturing a lifting tool;

7. The method of servicing a lower 500kVGIL tubular busbar without accompanying downtime of claim 1, wherein: in the step (2), the lower-layer intermediate phase GIL tubular bus passing through the high-altitude overlapped part of the highway is carried out according to the following steps:

8. Method for overhauling a lower 500kVGIL tubular busbar without accompanying downtime according to claim 7, characterized in that: in the step (2), the A, C-phase GIL tubular bus at the lower layer of the overhead overlapping part of the over-road is processed as follows:

when the hanger is detached, the antiskid lifting appliance assembly hook is firstly hung on a crane hook, the lifting belt on the inner side passes through the gap between the upper layer side A phase and the B phase or the C phase and the B phase GIL tubular bus, and the antiskid lifting belt is respectively looped and wrapped on the lower layer side A phase or the C phase GIL tubular bus; putting down a pair of lifting belts hooked on the small hooks along the outer sides of the side phase tubular buses, and using a tool U-shaped ring to wrap the lifting belts on the lower layer of the A-phase or C-phase tubular buses;

when the anti-skid hanger is installed, the anti-skid hanger is firstly hooked on a hook of a crane; then the hanging strip and the tool U-shaped annular pocket tubular bus are hooked on the small hook; then, hoisting the lower-layer GIL tubular bus of the side phase to the side of a set position by using a small hook, enabling a sling at the inner side of the sling, which is hooked on a large hook of a crane, to penetrate through the gap of the upper-layer middle-layer GIL tubular bus, and respectively looping and wrapping anti-skidding slings on the lower-layer side GIL tubular bus; and finally, commanding the big hook and the small hook of the crane to be matched, loosening and tightening, and gradually displacing the lower layer GIL tubular busbar to the position below the upper layer GIL tubular busbar by using a relative hoisting method.

9. The method of servicing a lower 500kVGIL tubular busbar without accompanying downtime of claim 1, wherein: in the step (2), the ultra-high and ultra-long vertical overlapped part of the A, C-phase GIL tubular bus is carried out as follows:

3. and after the crane is commanded to slowly fall down and the hanging strip of the inner side hook is completely loosened, the hanging strip of the inner side is removed, and the hanging strip of the outer side is used for hanging the vertical tubular bus of the phase A or phase C inner layer GIL to an open position and adjusting the vertical tubular bus to a horizontal state from a vertical state.

10. The method of servicing a lower 500kVGIL tubular busbar without accompanying downtime of claim 1, wherein: in the step (2), the ultrahigh and overlong vertically overlapped partial inner-layer intermediate-phase GIL tubular bus is carried out as follows: