In the stringing construction of 66kV and above transmission lines, it is often encountered that some conductors are worn due to various reasons in the construction, which need to be handled, which is inconvenient for the construction. According to the previous construction experience of transmission line stringing, the following research and methods of conductor abrasion prevention measures in construction are summarized.
The problem of conductor wear of transmission line often occurs in the past 66kV transmission lines. This problem is the key project of stringing construction quality acceptance, and will affect the future operation of the line. Therefore, how to effectively avoid the conductor wear and ensure the quality of the conductor in the construction process of the transmission line is an urgent issue to be studied and solved.
1. Wire wear during loading, unloading and transportation
The conductor is easy to wear in the process of loading, unloading and transportation and the anti-wear measures are as follows:
- 1.1 the conductor spool is deformed, the spool plate is lost, and the outer protective layer of the spool falls off.
Measures: appearance inspection is required before loading, unloading and transportation.
- 1.2 the bobbin rolls and overturns in the transport vehicle and collides with the surrounding.
Measures: during the transportation process, anchor measures such as skid are added under the line shaft to ensure that the spool can not be rolled and overturned at will, and the spool should be placed vertically instead of horizontally inverted.
- 1.3 improper wire hoisting method during loading and unloading.
Measures: hoist the wire spool with crane, and handle it with care, without collision, and the length of sling should be appropriate to prevent the axle from being squeezed and deformed by the sling. Pay attention to whether the side plate of the spool is damaged and handle it in time to prevent the wire from being abraded.
2. Wire wear during stringing
The conductor is easy to wear in the process of tension stringing and the anti-wear measures are as follows:
- 2.1 friction between conductor and spool car.
Measures: in the process of setting out, special personnel shall be assigned to take care of the spool car at any time. In case of friction, stop at any time to change the direction of the spool car or take measures such as soft cushion.
- 2.2 when the conductor shaft is changed, the snakeskin sleeve and the conductor are damaged.
Measures: check the quality of snakeskin cover before use to see if there are hard objects easy to scratch the wire, and handle it with care.
- 2.3 friction between the conductor and the crossing objects in the stringing block during the stringing process.
Under the condition that the tension of the conductor can not be calculated, the tension must be ensured before the construction.
- 2.4 friction between conductor and traction rope and guide rope.
Measures to be taken: friction shall be avoided in the laying of conductor, guide rope and traction rope, and the laying sequence shall be arranged. Make sure that there is no contact between the wire laying and the sag of the guide rope and the traction rope, and assign special personnel to monitor the setting out process at each tower position during the stringing process.
- 2.5 the conductor of tension tower is worn when the traction plate is overturned.
Measures: if the height difference between the two sides of the tension tower is large, the double pulley should be suspended with unequal height. In order to ensure that the flower car is always stressed, attention should be paid to its meaning, positioning and the length of the steel rope sleeve connection. The construction can be carried out after the calculation according to the height difference, span, tension and angle degree. If the tension tower rises, one or two pulleys can be hung upside down on the ground according to the angle. During the stringing and stringing construction, the conductor tension shall be adjusted stably to prevent impact, and the conditions of each gear shall be strictly monitored during the stringing process. Found money to check the quality of the rotary connector, rotation flexibility.
- 2.6 during the lifting operation, the traction rope rubs with the conductor, the conductor grinds with each other, releases the pressing wire rope, and the conductor jumps in the pulley during the lifting operation, which will wear the conductor.
Measures: according to the direction after the wire is lifted, the remote wire shall be lifted first and then lifted up in order to prevent poor collision between traction ropes or conductors. The soft rope shall be applied to the pressed rope released to Xi’an to prevent mutual friction between the conductor and the pressure rope. During crimping before lifting, the length of the remaining wire of the conductor shall be reduced as far as possible according to the cross crossing situation of each span along the line, so as to keep the safe clearance distance between the conductor and the ground.
- 2.7 abrasion between ground anchor wire part of conductor and tools.
Measures to be taken: anti abrasion measures shall be taken between the conductor and the tools, such as hanging glue for anchoring steel anchor, temporary anchoring steel rope and wire clamping device in the process of anchoring, and the wire shall be covered with rubber tube.
- 2.8 the conductor is worn when contacting with the ground.
Measures: before the conductor falls to the ground, protective and isolation facilities such as color strip cloth, straw mat and tarpaulin shall be laid on the ground to protect the conductor from direct contact with the ground, and the bracket shall be padded below to make it leave the ground and special personnel shall be assigned for protection.
3. Wire wear during accessory installation
- 3.1 wire lifting tools and wire wear.
Measures: use lifting rope and hook with glue, and the contact length between hook and wire is greater than 50mm.
- 3.2 conductor wear during spacer installation. During the installation of spacer, wire protection rubber tube shall be installed at the speed of not too fast, and the speed shall be stable and uniform. The brake shall be used according to the speed in the process of downhill running. When passing the suspension clamp, two people shall operate. The wire protection hose shall be installed on the wire at the inlet and outlet of the valve in advance.
The anti-wear protection measures of conductor is a long-term research project developed with new technology and new application. With the current environment of excessive energy consumption and gradual shortage of resources, our power transmission and transformation projects should adapt to the environment, improve the anti-wear measures of conductors, ensure the construction quality and save resources on the premise of understanding the new science and technology.