Double Eccentric Butterfly Valve, PN25/PN40, Ductile Iron
Features
Double eccentric & dual shafts |
Low torque, reduced pressure loss, energy saving. |
Sealing Options |
EPDM default, NBR, Viton, or metal seat for diverse media. |
Precision zero‑leakage |
SS welded seat micro‑finished, uniform disc sealing for bubble‑tight shutoff. |
Easy Maintenance |
Replace disc seal without dismantling; seat rings (bolted) also replaceable. |
FBE Coating |
250μm, Rubber and coatings that come into contact with drinking water have passed WRAS |
Bidirectional Sealing |
Compliant with EN1074-2 bidirectional sealing, arrow pointing directionn |
100% Hydrostatic Tested |
Each unit is tested according to EN 12266-1 (seat seal 1.1 x PN, shell 1.5 x PN) |
Certificates |
ISO9001, CE, WRAS, ACS |
Specifications
Design Standard |
EN 593 |
Top Flange Standard |
ISO 5211 |
End Flange Standard |
EN1092 PN40 |
Face to Face Dimension |
EN558-1 Series 14 |
Testing Standard |
API 598, EN12266 |
Temperature |
-20℃~80℃(depends on the sealing material) |
Body Material |
Ductile Iron EN GJS-400-15 / EN GJS-500-07 |
Disc Material |
Ductile Iron |
Shaft Material |
Stainless Steel |
Seat Material |
EPDM, WRAS EPDM |
Ring Material |
Carbon Steel, Stainless Steel |
Operator |
Bare Shaft, Gearbox, Pneumatic, Electric Actuator |
Dimension
|
Size |
L |
T / Ф |
PN10 |
PN16 |
PN25 |
Top Flange |
||||
|
Series 13 |
Series 14 |
Ф D |
n - Ф d |
Ф D |
n - Ф d |
Ф D |
n - Ф d |
|||
|
DN100 |
127 |
190 |
11*11 |
180 |
8-19 |
180 |
8-19 |
F07 |
||
|
DN125 |
140 |
200 |
14*14 |
210 |
8-19 |
210 |
8-19 |
F07 |
||
|
DN150 |
140 |
210 |
14*14 |
240 |
8-23 |
240 |
8-23 |
F07 |
||
|
DN200 |
152 |
230 |
17*17 |
295 |
8-23 |
295 |
12-23 |
F10 |
||
|
DN250 |
165 |
250 |
19*19 |
350 |
12-23 |
355 |
12-28 |
F10 |
||
|
DN300 |
178 |
270 |
22*22 |
400 |
12-23 |
410 |
12-28 |
430 |
12-28 |
F10 |
|
DN350 |
190 |
290 |
22*22 |
460 |
16-23 |
470 |
16-28 |
490 |
16-28 |
F10 |
|
DN400 |
216 |
310 |
27*27 |
515 |
16-28 |
525 |
16-31 |
550 |
16-31 |
F14 |
|
DN450 |
222 |
330 |
27*27 |
565 |
20-28 |
585 |
20-31 |
600 |
20-31 |
F14 |
|
DN500 |
229 |
350 |
36*36 |
620 |
20-28 |
650 |
20-34 |
660 |
20-34 |
F14 |
|
DN600 |
267 |
390 |
46*46 |
725 |
20-31 |
770 |
20-37 |
770 |
20-37 |
F16 |
|
DN700 |
292 |
430 |
63.35 |
840 |
24-31 |
840 |
24-37 |
875 |
24-37 |
F25 |
|
DN800 |
318 |
470 |
63.35 |
950 |
24-34 |
950 |
24-41 |
990 |
24-41 |
F25 |
|
DN900 |
330 |
510 |
75 |
1050 |
28-34 |
1050 |
28-41 |
1090 |
28-41 |
F25 |
|
DN1000 |
410 |
550 |
85 |
1160 |
28-37 |
1170 |
28-44 |
1210 |
28-44 |
F25 |
|
DN1200 |
470 |
630 |
105 |
1380 |
32-41 |
1390 |
32-50 |
1420 |
32-50 |
F30 |
WRAS Certified Ductile Iron Double Eccentric Butterfly Valve
WRAS certified ductile iron double eccentric butterfly valve is designed for reliable flow isolation and control in drinking water, water treatment, and industrial pipeline systems. Featuring a double offset disc design and high-performance sealing structure, this butterfly valve provides reduced operating torque, extended service life, and excellent sealing performance.
Manufactured with a ductile iron body and corrosion-resistant coating, the valve is suitable for water supply networks, pumping stations, reservoirs, and other demanding water applications where durability and hygienic performance are required.
KEFA VALVE is a professional OEM butterfly valve manufacturer in China, supplying WRAS approved double eccentric butterfly valves with customized materials, pressure ratings, dimensions, and actuation solutions for global customers.
Components
| NO. | Part | Material |
|---|---|---|
| 1 | Bolt | Stainless Steel A2 |
| 2 | Cover | Ductile Iron EN-GJS-400/500 (GGG40/50) |
| 3 | O Ring | EPDM / NBR |
| 4 | Bushing | Steel / Bronze |
| 5 | Body | Ductile Iron EN-GJS-400/500 (GGG40/50) |
| 6 | Body Seat | Welding SS304 / SS316 |
| 7 | Disc Seat | EPDM / NBR / VITON |
| 8 | Bolt | Stainless Steel A2 |
| 9 | Disc | Ductile Iron EN-GJS-400/500 (GGG40/50) |
| 10 | Lower Shaft | SS420 / SS304 / SS316 / SS431 / 17-4PH |
| 11 | Upper Shaft | SS420 / SS304 / SS316 / SS431 / 17-4PH |
| 12 | Taper Pins | SS420 / SS304 / SS316 |
| 13 | Stamping Ring | Q235 / SS304 / SS316 |
| 14 | O Ring | EPDM / NBR |
| 15 | Cover | Ductile Iron EN-GJS-400/500 (GGG40/50) |
| 16 | Bolt | Stainless Steel A2 |
Downloads
Frequently Asked Questions
Everything you need to know about double eccentric butterfly valves, including design features, materials, applications and performance.
What is a double eccentric butterfly valve?
A double eccentric butterfly valve is a flange-end valve featuring a double-offset design. The valve stem axis is offset from both the disc center and the body center, allowing the disc to quickly disengage from the seat during opening. This design reduces sealing friction, lowers operating torque and extends the service life of the valve.
What materials are available for double eccentric butterfly valves?
Double eccentric butterfly valves are commonly manufactured with ductile iron bodies such as EN GJS-400-15 or EN GJS-500-7. Seat materials can include EPDM, NBR and FKM depending on the operating medium, temperature and application requirements.
What are the advantages of double eccentric butterfly valves?
The main advantage of a double eccentric butterfly valve is its double-offset geometry, which minimizes contact between the disc and seat during operation. This significantly reduces friction, operating torque and wear, providing reliable sealing performance and longer service life.
What applications are these valves typically used in?
Double eccentric butterfly valves are widely used in water supply and drainage systems, wastewater treatment plants, power plant cooling systems, municipal networks and industrial water applications, especially where reliable shut-off and frequent operation are required.
Are double eccentric butterfly valves suitable for drinking water?
Yes. When manufactured with suitable certified materials, such as WRAS or ACS approved sealing materials, double eccentric butterfly valves can be used in potable water distribution systems. Certification requirements depend on the target market and local drinking water regulations.
