CHECK VALVES AND STRAINERS

Anti-hammer relief valve

Application

Sewerage Network protection

Network Protection

Product family

Pipeline protection

A pressure relief valve is a safety appliance which is capable of instantaneously evacuating a high flow rate.

It protects networks against overpressure due to sudden changes in flow rates (water hammer effects) for example when closing a valve too quickly or in case of sudden moving of air pockets inside the pipes.

The range goes from DN60 to DN200, PFA10, 16 or 25 bars.

The valve pressure set point has to be indicated by the customer at the order time.

Technical design


60	16	400	720	46	1.5	with spring 1 to 7 bar	34	172525
65	16	400	720	46	1.5	with spring 1 to 7 bar	34	167036
80	16	400	720	85	1.5	with spring 1 to 7 bar	38	167045
100	16	400	720	120	1.6	with spring 1 to 7 bar	42	167065
125	16	470	720	160	1.8	with spring 1 to 7 bar	54	161855
150	16	530	820	280	2	with spring 1 to 7 bar	78	161858
200	10	580	820	390	2	with spring 1 to 7 bar	88	161860
60	1016	400	720	65	1.8	with spring 6 to 12 bar	34	161866
65	1016	400	720	65	1.8	with spring 6 to 12 bar	34	161853
80	1016	400	720	130	2	with spring 6 to 12 bar	38	167046
100	1016	400	720	180	2	with spring 6 to 12 bar	42	161872
125	1016	470	720	290	2.5	with spring 6 to 12 bar	54	161856
150	1016	530	820	400	2.5	with spring 6 to 12 bar	78	167093
200	10	580	820	680	2.7	with spring 6 to 12 bar	88	167105
200	16	580	820	680	2.7	with spring 6 to 12 bar	88	161861
60	16	400	720	85	2.5	with spring 10 to 17 bar	34	161849
65	16	400	720	85	2.5	with spring 10 to 17 bar	34	161863
80	16	400	720	160	2.5	with spring 10 to 17 bar	38	167047
100	16	400	720	260	2.6	with spring 10 to 17 bar	42	167068
125	16	470	720	350	2.8	with spring 10 to 17 bar	54	161857
150	16	530	820	480	3	with spring 10 to 17 bar	78	173616
200	16	580	820	886	3.5	with spring 10 to 17 bar	88	167106
60	25	400	720	95	3.5	with spring 16 to 25 bar	34	161850
65	25	400	720	95	3.5	with spring 16 to 25 bar	34	161852
80	25	400	720	180	3.7	with spring 16 to 25 bar	38	161854
100	25	400	720	300	3.8	with spring 16 to 25 bar	42	167066
125	25	470	720	405	3.8	with spring 16 to 25 bar	54	167077
150	25	530	820	525	4	with spring 16 to 25 bar	78	167091
200	25	580	820	960	5	with spring 16 to 25 bar	88	161875

Features

Material and coating

Item	Designation	Material	Coating
1	Adjusting screw	Stainless steel 18/8
2	Nut	Stainless steel A2
3	Nut	Bronze UE 7
4	Cap	Ductile Iron	Epoxy 200 microns
5	Spring holder	Steel XC 38
6	Spring	Spec Steel
7	Spring holder	Steel XC 38
8	Pin	Stainless steel
9	Bearing	Bronze UE 7
10	Clapper	Steel XC 38
11	Clapper gasket	Polyurethane
12	Upper stem	Stainless steel 18/8
13	Seat	Stainless steel 18/8
14	O’ring	Nitrile
15	Skirt	Steel A40	Epoxy 200 microns
16	Flange	Steel XC 38	Epoxy 200 microns
17	Pressure ¼’ gas

Hydraulic characteristics

The pressure values to be considered are:

PMS : network maximum service Pressure,
Valve pressure set point : Pressure at beginning of opening,
Overpressure: Pressure increase, compared with the pressure set point, to reach the maximum drained flow rate.

The valve pressure set point has to be indicated by the customer at the order time.

The valve pressure set point is given by the network maximum service Pressure (PMS) increased by 5 to 10 %.

Choice of DN

DN of the appliance is determined as a function of the flow rate to be evacuated. As a general rule we should choose the flow rate of the pipe on which the relied valve is located

Installation

The pressure relief valve is to be installed in a vertical position as close as possible to the source of the water hammer effects.

If it is installed in a manhole, an evacuation pipe must be provided. An isolating valve is recommended to enable work to be carried out on the relief valve (regulating, maintenance…) without interrupting the operation of the network.