To ensure a neat Floppy Sprinkler Overhead Cable installation, pipe tensioning springs should be used at the end of each lateral line to compensate for the expansion and contraction in the polyethylene pipe due to temperature fluctuations. Polyethylene pipe expands and contracts about 2mm per meter for every 10°C change in temperature.

The easiest way to install a tensioning spring is to thread a flat steel hose clamp (Jubilee clamp) onto one end of the spring’s hook or end loop, as one would attach a key onto a key ring. Then insert the end of the pipe through the hose clamp and pull the clamp and pipe up to the desired position.

Fasten the other end of the spring to the pole at the same height as the pipe, which is hanging in the pipe hangers. Pull the lateral pipe towards the pole so that excessive slack is taken up and then tighten the clamp around the lateral pipe.

To aid with the installation of pipe tensioning springs, consult the graph below. This is for a spring of 2.6mm material thickness, 25mm outside diameter and 400mm length.

Graph 8.1