Abstract
Damages resulting from line towers cascade, in case of ice or soft snow loadings are well known by
electricians who try to prevent this by various methods. The idea developed by E.D.F. consists in designing the
towers for the most representative loading cases in view of the stress which the increased weight of the conductors
puts on them ; cases of unequal ice loading are included. In order to limit longitudinal loads, conductors are
fastened in suspension clamps which allow them to slide as soon as the load goes beyond the selected threshold
value. For many years now, this type of clamp has proved its worthiness as a mechanical fuse in preventing cascade
tower breakdowns.
A calculation program makes it possible to define the minimum length and radius of curvature of the clamp
cradle in tenns of the required operating conditions: the winding angle of the conductor, the vertical load applied
to the clamp. The following conductor parameters are taken into account : pressures allowed between conductor
strands and between the strands and the cradle of the clamp and the stresses induced into the conductor strands
by the loads which the conductor must sustain. This calculation method can be applied to any type of conductor.
The main ·technological aängements adopted for the controlled sliding suspension clamps are explained.
The sliding process of the conductor in the clamp, in case of a longitudinal load, is examined within various
operating conditions of the conductor, basically with ice loads and with accidental conditions such as conductor
breakdowns.
Users
Please
log in to take part in the discussion (add own reviews or comments).