








Triple functions air valve type "D" 4000 – 6000 – 9000
![]() | Low and high pressure air relief valve (double effect):the device evacuates great air amounts during the filling of the main, allows the inlet of great air amounts (in order to avoid a vacuum effect) during the emptying of the main and evacuates small air amounts that are accumulated in the high points of the main during normal working conditions |
Material and coating
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Standard version
Item | Quantity | Description | Material | Coating |
01 | 01 | Body | Ductile iron GS 400-15 | Blue epoxy 250 microns |
02 | 01 | Upper flange | Ductile iron GS 400-15 | |
03 | 01 | Cover | Ductile iron GS 400-15 | |
04 | 01 | Protection grid | Stainless steel A2 | |
05 | 01 | Cover | Stainless steel A2 | |
06 | 04 | Threaded bar | Stainless steel A2 | |
07 | 08 | Nut | Stainless steel A2 | |
08 | 04 | Washer | Stainless steel A2 | |
09 | 04 | Screw | Stainless steel A2 | |
10 | 04 | Nut | Stainless steel A2 | |
11 | 04 | Washer | Stainless steel A2 | |
12 | 01 | Float | ABS | |
13 | 01 | Float guide | ABS | |
14 | 01 | Ring | ABS | |
15 | 01 | Gasket seat | ABS | |
16 | 01 | Lip seal | EPDM | |
17 | 01 | Float | ABS | |
18 | 01 | Nozzle | PA6.6 Polyamide | |
19 | 01 | Nut | ABS | |
20 | 01 | Gasket | EPDM 55 | |
21 | 01 | O-ring | EPDM 55 | |
22 | 01 | Gasket | EPDM 55 | |
23 | 01 | Adjusting screw | Stainless steel A2 | |
24 | 01 | Pin | Stainless steel | |
25 | 01 | Air valve | Brass |
Reinforced version
Item | Quantity | Description | Material | Coating |
01 | 01 | Body | Ductile iron GS 400-15 | Blue epoxy 300 microns |
02 | 01 | Upper flange | Ductile iron GS 400-15 | |
03 | 01 | Cover | Ductile iron GS 400-15 | |
04 | 01 | Protection grid | Stainless steel A4 | |
05 | 01 | Cover | Stainless steel A4 | |
06 | 04 | Threaded bar | Stainless steel A4 | |
07 | 08 | Nut | Stainless steel A4 | |
08 | 04 | Washer | Stainless steel A4 | |
09 | 04 | Screw | Stainless steel A4 | |
10 | 04 | Nut | Stainless steel A4 | |
11 | 04 | Washer | Stainless steel A4 | |
12 | 01 | Float | ABS | |
13 | 01 | Float guide | ABS | |
14 | 01 | Ring | ABS | |
15 | 01 | Gasket seat | ABS | |
16 | 01 | Lip seal | EPDM | |
17 | 01 | Float | ABS | |
18 | 01 | Nozzle | PA6.6 Polyamide | |
19 | 01 | Nut | ABS | |
20 | 01 | Gasket | EPDM 55 | |
21 | 01 | O-ring | EPDM 55 | |
22 | 01 | Gasket | EPDM 55 | |
23 | 01 | Adjusting screw | Stainless steel A4 | |
24 | 01 | Pin | Stainless steel | |
25 | 01 | Air valve | Brass |
Kinetic principle
Pipeline filling During the filling of the pipe,the air evacuates, the float remains in low position. The water fills gradually the air relief valve, under the effect of the Archimedesthrust the edge of the seal ring and the surface of the float allows to have a tightness.The flow of the high orifice pressure being far more weak, it remains a air feeder thatevacuates slowly and allows a slow placement in pressure of the valve avoiding eater hammer. The unit is in under pressure and orifices of evacuation are sealed. Pipeline degassing The air accumulates during the functioning of the pipe.The low pressure float remains in place under the effect of the pressuredespite the decline of the level of the water.The air evacuates by the small orifice with the same mechanism that the precedingparagraph 2. Pipeline emptying In case of emptying of the network or rupture of the pipe,the low pressure float instantaneously allowing the arrivalof air and avoiding the placement in depression of the conduct.
Performances
Air flow large orifice
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Air flow small orifice
Constant flow from 1 bar (10MCE)
PFA in Bar (all DN) | 16 | 25 |
Ø nozzle in mm | 2,25 | 1,75 |
Air flow in m3/h at pipe pressure | 2,79 | 1,69 |
Hydraulic sealing: sealing wraps to 1.5 PN - sealing low pressure starting from 0.3 bars for small (nozzle) and large openings.