Insulating joints

Insulating joints: overview

Monobloc insulating joints and insulating kits make it possible to electrically isolate a zone under the influence of cathodic protection on a pipeline. The monobloc insulating joints (series 150 to 2500) are welded onto the pipelines; made of forged parts and insulating parts, they are assembled and inspected in the factory (test certificates supplied).

The insulating kits (series 150 to 1500, maximum service temperature 80 °C) are assembled between flanges. The AA1 kit comprises an annular gasket bonded between two sealing gaskets, sleeves and insulating washers; the AA4 kit takes the AA1 kit and adds its bolting (bolts or threaded rods, washers and nuts, with material certificate).

Where to place an insulating joint

At the boundaries of the protected structure: at the inlet and outlet of a pressure reduction or metering station, at the connection to a third-party network, at the entrance to an industrial site, or on either side of an area affected by stray currents. Each joint defines a section whose protection can be sized and measured independently.

Monobloc or kit?

The monobloc joint, welded and non-removable, suits buried and permanent locations. The insulating kit is fitted between two existing flanges, which makes it suitable for accessible installations, in stations or above ground, where intervention must remain possible. In both cases, insulation is checked after installation: a short-circuited joint cancels the electrical separation without showing it.

Insulating joints: technical specifications

Insulating joints: documentation