Brief Discussion On The Main Functions And Installation Requirements Of Galvanized Crossarms
The main functions of Pre-insulated Sleeve:
(1) Support the conductor through the insulator, so that the phase line and the neutral line have a certain space insulation distance in the middle of the distance and on the pole.
(2) When supporting the conductor, it must be subjected to the force of the conductor, such as the weight of the conductor, the wind pressure of the conductor, and the tension of the conductor. Therefore, it should have a certain mechanical strength, otherwise it will cause serious galvanized cross arm breakage accidents.
Installation requirements of galvanized cross arm:
Galvanized cross arm is generally installed 300mm from the top of the pole. In order to facilitate the identification of the power supply side during maintenance and inspection, the single galvanized cross arm should be installed on the receiving side; the single-mode cross arm of the 90° corner pole, terminal pole, and branch pole should be installed on the wire pulling side, and the galvanized cross arm support iron should be installed on the left side facing the receiving side. In addition, the unified installation process can form a regular process for future maintenance and inspection work, avoid missing inspection items, and make it easy to find defects.
The vertical and horizontal installation errors of galvanized crossarms mainly consider the following:
(1) The impact of vertical error on sag within the span: The difference in sag of each phase line within the span should not be greater than 50mm. If the vertical tilt error of the galvanized crossarm is greater than 25mm, the difference in the lowest point of the conductor will be greatly enlarged, thereby increasing the risk of wind deviation approaching or even mixing lines, and it cannot meet the requirements of sag error, so it should be limited.
(2) Horizontal tilt and torsion error adds harmful external forces to the galvanized crossarms, poles and insulation after the line is erected.
