Metal cross arm for power lines - uses deformable metal cross-arm on overhead power lines which bends if excessive mechanical loading occurs on cables or poles

摘要

To minimise damage to overhead electric power lines due to excessive loading on the cables or poles, arising from snow, wind, impact or other causes of excessive cable tension, a deformable cross arm is used which is more readily and cheaply replaced then broken cables or poles. The cross arm is mounted near the top of the pole using a bracket and bolts. Passing horizontally through the mounting bracket, is a short length of square section metal tube. A metal angle section is passed through the square tube to form the cross arm. It has mounting brackets for the cable suspension at either end. The dimensions of both metal sections are chosen to give plastic deformation above a specified loading. A third conductor may be mounted in holes provided on the bracket used to fix the cross arm to the pole.