Pressure and Angular Deviation at the Joint

Pressure and angular deviation at the joint

Technical solutions

With the term “pressure”, a distinction needs to be drawn between terminology used by:
– the network designer (dependent on the hydraulic capacity),
– the manufacturer (dependent on the product performance),
– the network user (dependent on the service).

Terminology

The terminology listed below is drawn from the draft European standard EN 805 – Water supply. Specification for external networks and components – applicable to all materials.

The product standard EN 545 - Ductile cast iron pipes and fittings - uses this terminology where the manufacturer is concerned.

	Abreviation
	Terminology
designer	dp	Design pressure
	Mdp	Maximum design pressure
	Stp	System test pressure
manufacturer	pfA	Allowable operating pressure
	pMA	Allowable maximum operating pressure
	peA	Allowable test pressure
user	op	Operating pressure
user	Sp	Service pressure

Manufacturer’s definitions

PN - Nominal pressure (in compliance with Standard EN 545)

Numerical designation expressed by a number used for reference purposes. All flanged components with the same DN and designated by the same PN are compatible for interconnection.
Standard EN 545 sets out for flanged pipes and fittings, the following PN equivalents in PFA, PMA and PEA.

DN	PN 10			PN 16			PN 25			PN 40
DN	PFA	PMA	PEA	PFA	PMA	PEA	PFA	PMA	PEA	PFA	PMA	PEA
40 to 50	See PN 40			See PN 40			See PN 40			40	48	53
60 to 80	See PN 16			16	20	25	See PN 40			40	48	53
100 to 150	See PN 16			16	20	25	25	30	35	40	48	53
200 to 300	10	12	17	16	20	25	25	30	35	40	48	53
350 to 1 200	10	12	17	16	20	25	25	30	35	–	–	–
1400 to 2000	10	12	17	16	20	25	–	–	–	–	–	–
For DN 80 flanged parts manufactured by PAM, use the following equivalents:

80	See PN 40			See PN 40			See PN 40			40	48	53

Leaktightness test pressure (in the sense of Standard EN 545)

Pressure applied to a component during its manufacture to ensure its leaktightness.

Subdomains

Safety factor

Safety factor of ductile iron pipelines.

Water hammer

If protection devices have not been provided, ductile iron pipes have a safety coefficient which is often useful when faced with accidental pressure surges.

Joint deflection

The angular deflection allows negotiation of large radius bends.

Hydraulic thrust and anchoring

Hydraulic thrust in ductile cast iron pipelines

Allowable Operating Pressure

Discover how are Saint-Gobain PAM pipes designed to withstand high pressures.