Flexible inserts are duct elements whose tasks are to reduce the level of vibration emanating from a running fan, as well as to compensate for minor temperature deformations in the duct network. Usually flexible connectors are used when the ventilation system has a branched network of air ducts, in which radial, centrifugal fans are mounted.
Flexible inserts are installed on the fan or exhaust fan exhaust, i.e. on the discharge, or on the fan suction pipe, i.e. at the inlet. For the first variant, flexible connectors of type H are used, and for the second, flexible connectors of type B.
Flexible connectors type H have a square section, type B have a round section.