Therefore, the crossing operation is carried out by means of live network closure.
Special operation personnel must have valid certificates, such as high-altitude operation worker, grinder and tail grinder.
The construction schemes such as stringing operation instructions and construction scheme for crossing 220kV power line have been compiled and approved according to the required procedures.
In the construction of Fenghuang Xishan Dongjiao 750kV Transmission Line Project, there are many crossing power lines, including 220kV transmission line crossing for 7 times, 110kV transmission line crossing for 5 times and 35kV Transmission line crossing for 4 times.
3.4 preparation of machines and tools} the conductor and ground wire pulley of the paying off section has been hung in advance.
In order to ensure the smooth completion of crossing and stringing construction and the safe operation of the crossed line, The following operation scheme is specially prepared.
The span of g2-g3 of the line is 368m; G2 tower type is jg3h-48m, with full height of 66m and conductor cross arm width of 23m; G3 tower type is zb292h-57m, with full height of 64.4m and conductor cross arm width of 39.6m; The height difference between the hanging points of the two towers is 9m.
After the joint review of the construction drawings, the design has carried out the construction drawing disclosure.
It is difficult to set up ordinary steel pipe crossing frames and bamboo crossing frames.
3.5.
03 basic preparation before crossing stringing # 3.1 technical preparation # tension frame section is g1-g10 and crossing gear is g2-g3.
The crossing frame shall be transported to the operation site the day before the construction after the application for crossing is approved, and the commissioning is in good condition.
For live crossing application, special personnel shall be assigned to handle live crossing application, live line exit reclosing application and work ticket with the operation unit according to the procedures..
The building of crossing frames covers a large area and it is difficult to requisition land, Most of the crossed power lines are important power supply lines, and it is difficult to handle power failure crossing.
General workers must work under the leadership of technicians.
All constructors participating in crossing and stringing must participate in the construction safety technical disclosure before operation.
The new Fenghuang Xishan Dongjiao 750kV Transmission Line project crosses Fengjia 220kV primary and secondary transmission lines, which belongs to a large infrastructure operation site.
2.2 determination of span scheme: Fengjia 220kV power transmission line in this span is a double circuit line.
G2 tower adopts the tower cross arm as the cableway truss, and G3 tower installs the temporary cross arm as the cableway truss at the nodes of upper and lower curved arms, with 6 Φ 16 dinima insulating ropes, 27 insulated FRP pipes and 8 fixed length insulating ropes are capped to form three 6m wide shielding nets to protect the cross domain sections of Fengjia 220kV primary and secondary power transmission lines.
All construction personnel participating in crossing and stringing shall receive pre job training and take up their posts only after passing the examination.
Fengjia 220kV power transmission line is a double circuit line, and the vertical height of Fengjia 220kV ground wire to the ground at the intersection of the two lines is 34m; The width of the two lines is the same as that of the middle line, which is 12.6m, the upper line width is 8.6m, the lower line width is 10m, the line crossing angle is 77 ° 40 ‘, the horizontal distance between the crossing point and the center of G2 tower is 55m, and the height difference between the ground wire of 220kV Fengjia power transmission line and the hanging point of G2 tower is 14m.
3.2 personnel preparation management personnel and construction personnel (20 crossing erection team, 30 stringing construction team and 30 accessory installation team) are complete and arrive at the designated post or on standby.
In order to ensure the construction period and safe construction, the QC team of the project department studies the live crossing construction and determines to adopt the live network closure method for the crossing construction.
According to the field survey, the crossed 220kV Fengjia line is a double circuit line on the same tower.
The crossed Fengjia 220kV primary and secondary power transmission lines are important output line channels of Fenghuang substation.
In order to ensure the normal operation of Fengjia 220kV first and second circuit power transmission lines, using the height of G2 and G3 towers and the natural conditions close to Fengjia 220kV first and second circuit power transmission lines, 3-phase 6M wide and 32m long insulated glass fiber reinforced plastic closed network Cableways are set up between G2 and G3 towers to protect Fengjia 220kV first and second circuit power transmission lines Two circuit power transmission line.
02 work content # 2.1 basic situation of crossing # during the stringing construction of g1-g10 paying off section, cross Fengjia 220kV first and second circuit power transmission lines in g2-g3, and the crossing position is between tower 0002 and tower 0003 of Fengjia 220kV first and second circuit power transmission lines, 136m away from tower 0002.
The tensioning equipment has been mobilized, installed in place, commissioned and in good condition according to the construction requirements.
After the shielding net of insulated steel pipe cableway is erected, the conductor, ground wire and optical cable shall be laid, balanced hanging, tightening and accessory installation.
The anchor line ground anchor of the tensioning yard and the ground anchor of the cable bridge crossing frame have been buried and passed the inspection.
Double Head Lifting Pin Anchor
The crossed line is relatively high and it is difficult to cut off power.
The path length is 64.581km.
The design wind speed is 29m / s and 31m / s, and the maximum design icing is 10mm, Conductor model: lgj-400 / 50; Model of ground wire: jlb20a-150 and gj-120, opgw-150 and opgw120.
01 project overview bid section I of Fenghuang Xishan Dongjiao 750kV Transmission Line project starts from 750kV Fenghuang substation in Manas County, Changji Prefecture, Xinjiang Uygur Autonomous Region and ends at J25 on the East Bank of Hutubi River, Hutubi County.
The power umbrella shall be reported for approval before use and transported to the site in advance.
The following takes the live crossing of the first and second circuit lines of 220kV Fengjia line as an example.
3.3 material preparation} the materials required for stringing shall be transported to the tensioning and traction yard, placed neatly, standardized, clearly marked, passed the on-site inspection, and the specifications and quantity meet the construction needs.
The crossing line is high and the crossing angle is small.
A total of 139 iron towers are erected with single circuit conductor and ground wire.
Other relevant construction tools and instruments shall be prepared and transported to the site as required, and the site inspection shall be qualified.
