Internal pressure resistance

Last updated on Thu, 12/06/2012 - 14:34

In drainage networks, internal overpressure rarely occurs and is always accidental. Thrust efforts in the overloaded sections have to be addressed to guarantee both water tightness and mechanical stability.
As the robust cast iron components can address any pressure hazard, so the couplings will be submitted to the strain.
The quality of the couplings and their careful selection according to their field of use will prevent misalignment or disconnection of the pipework.

Resistance of the couplings to hydrostatic pressure

Standard pressure mechanical couplings:

Wastewater drainage systems – which differ from rainwater drainage systems as regards pressure – are connected to sanitary appliances installed on each storey which may serve as outlets in case of accidental overloading (due to blockages, for example).
The pressures that occur cannot therefore exceed the pressure corresponding to the height of one storey, i.e. about 0.3 bars.
The couplings we describe as "standard" are perfectly suitable for this common type of application.

High-pressure mechanical couplings:

In some rare cases, a wastewater drainage system may pass through a number of storeys without any outlet and there could be a risk of overloading (blockage due to operation or saturation of the sewer main).
The pressure resistance required to ensure that these systems remain leaktight and stable in such cases calls for high-pressure couplings able to withstand a pressure up to 10 bars.


Securing the runs submitted to end thrust forces

The simplest solution is to use to the standard mechanical couplings and secure them with grip collars. In this case, the maximum performance of both is limited by the weakest performance of the two products. (See Focus)


An alternative solution consists in selecting high pressure couplings with grips, or self-anchored high pressure couplings. 



Check the hydrostatic pressure performance of the couplings used along with the pressure performance given for the relevant grip collar.