Overhead Lightning Wire Dropping Caused by Suspension Clamp Abrasion and Its Prevention

1. Reason Analysis
According to the survey, the locations where overhead lightning conductors dropped are all located in areas with strong winds. According to experience, there are two reasons why the lightning conductors dropped due to the wear of the suspension clamps:
(1) Due to the effect of wind force, relative movement occurs between the hull of the suspension clamp and the hanging plate, and the hanging plate swings around the hull hanging shaft at a small angle. Due to the thinness of the hanging plate, its swinging effect is like a groove cut by a blade, which causes the stressed section of the hull hanging shaft to become thinner and smaller. When the groove reaches a certain level, under the action of the weight of the lightning conductor itself, the clamp If the hull of the ship falls from the suspension clamp, the lightning protection line will be dropped and grounded;
(2) If the suspension clamp is too large or the lightning conductor is not pressed tightly, the lightning conductor and the hull of the clamp will move relative to each other under the action of wind force, causing the lightning conductor to wear; under the action of wind force or strong lightning current, it will be broken Or burn the lightning conductor, thus causing the lightning conductor to fall off from the suspension clamp, and an accident similar to the above occurs.
2. Preventive measures
(1) The hanging plate on the hull hanging shaft of the suspension line clamp is fixed by a bolt. There is a flat gasket in the bolt. The gasket covers the connection part of the hanging shaft. If the gasket is not opened, it is difficult to find the hull hanging shaft Therefore, when checking the wear degree of the hanging shaft, the latch must be removed and the gasket must be opened. At the same time, temporary measures should be taken to prevent the lightning wire from falling during the inspection.
(2) In order to prevent the wear of the lightning protection wire, the size of the suspension clamp should be selected according to the cross section of the lightning protection wire. During the construction, the aluminum tape of the lightning protection wire at the clamp should be wrapped strictly according to the process requirements and the lightning protection wire should be pressed tightly. .
(3) In line design, only the load of the fittings is required, while other strength parameters are not required to be inspected. Therefore, in areas with strong wind and large wind deflection, when selecting suspension clamps for line design and construction, you should consider choosing wear-resistant clamps (such as various alloys) and suspension clamps with windproof components.
(4) During normal line maintenance work, especially the annual overhaul of the line, it should be strictly followed the rules and regulations, and all kinds of suspension clamps should be opened and inspected according to the regulations.
The inspection of line suspension clamps is a link that is often neglected in line maintenance work. While strengthening the construction process and material selection, daily maintenance management should also be strengthened, and an account should be set up for the pole sections that are prone to wear of suspension clamps , shorten the clamp inspection cycle, increase the inspection items of the hanging clamp in the daily inspection, etc.