1. Cause analysis
According to the survey, the occurrence of overhead lightning lines off the line of the lot is in windy areas. Experience check due to the wear of the preformed suspension clamp caused by the lightning line off the line for two reasons:
(1) because of the role of wind. Preformed suspension clamp between the hull and hanging plate relative movement, hanging plate around the hull hanging axis for a small angle of the swing. As the pegboard is thin, its swinging action is like a blade cutting down and groove marks appear, resulting in the hull hanging axis of the force cross-section becoming thin and small. When the slot marks reach a certain level, in the lightning line itself under the weight, the hull of the line clip from the preformed suspension clamp fall, the lightning line off the line grounding accident;
(2) overhanging line clip is too large or the lightning line is not pressed. Lightning line and line clip hull in the role of the wind, the relative motion, resulting in the wear and tear of the lightning line. In the wind or a strong lightning flow, scraping or burning lightning line. Thus causing the lightning line from the dangling line to clip off, occurring with the above similar accidents.
2. Preventive measures
(1) the hull of the pendant line clip hanging axis on the hanging plate is fixed through the pin. There is a flat shim inside the pin, the shim covers the connection part of the hanging shaft. Without opening the spacer, it is difficult to find the wear of the hull pendant shaft. Therefore, when checking the wear of the pendant shaft, the pin must be removed and the shim opened. At the same time, the inspection should also pay attention to doing a good job to prevent lightning line fall temporary measures.
(2) in order to prevent the wear and tear of the lightning line, the lightning line should be selected according to the cross-section to the size of the preformed suspension clamp. In the construction of the lightning line in strict accordance with the requirements of the process the clamps of the aluminum wrapping and the lightning line pressure tight.
(3) in the line design, only the fixture load requirements, while other strength parameters are not required to test. Therefore, in the stronger wind, wind deflection areas, line design, construction selection of preformed suspension clamp, should consider picking wear-resistant line clip (such as a variety of alloy class) and have anti-wind deflection components of the preformed suspension clamp.
(4) the usual line maintenance work, especially the annual inspection of the line overhaul should be carried out strictly in accordance with the rules and regulations. All types of preformed suspension clamps should be opened according to the provisions of the inspection.
The inspection of the line preformed suspension clamp is a part of the line maintenance work often neglected. Strengthening the construction process and material selection at the same time should also strengthen the usual maintenance management. The susceptibility of the pole section of the pendant clip wear set up a ledger, shortening the clip inspection cycle. In the daily inspection to increase the overhanging line clip inspection project.