A Double Flange Double Eccentric Butterfly Valve is a high-performance quarter-turn valve designed for demanding industrial applications requiring reliable shut-off, reduced wear, and extended service life.
Unlike concentric (centric) designs, this valve features two offsets:
The stem is offset behind the disc centerline (first eccentricity),
The stem axis is offset from the pipe centerline (second eccentricity).
This double-offset geometry causes the disc to cam into the seat during the final degrees of closing, creating a tight seal with minimal contact during operation—reducing friction, wear, and operating torque.
The double flange body design includes integral flanges on both ends, allowing it to be bolted directly between pipe flanges using a single set of through-bolts—providing robust, aligned installation suitable for higher pressure and temperature services.
Technical Attributes
1,Design Standard,EN 593 / AWWA C504 / API 609
2,Body Type,Double Flanged (Integral flanges)
3,Eccentricity,Double Offset (Stem is offset in two planes)
4,Pressure Rating,PN10 / PN16 / PN25 / Class 150
5,Size Range,DN100 to DN3000+
6,Face-to-Face,EN 558 Series 13 / Series 14 / ISO 5752
7,Body Material,Ductile Iron GGG50 / GJS-500-7
8,Disc Material,Ductile Iron (Epoxy coated) / SS316 / Al-Bronze
9,Seat Type,Resilient Sealing Ring (Typically on the disc)
10,Seat Material,EPDM / NBR (Retained by a stainless steel ring)
11,Body Seat,Stainless Steel (Welded or overlayed on body)
12,Stem Material,Stainless Steel AISI 420 / 431 / 316 / 630
13,Stem Sealing,Multiple O-rings or V-type packing (Replaceable)
14,Shaft Bearing,Self-lubricating Bronze or PTFE-lined Steel
15,Tightness Class,EN 12266 Rate A (Bubble-tight shut-off)
16,Operation,"Worm Gearbox (Standard), Electric or Pneumatic"
17,Coating,"Fusion Bonded Epoxy (FBE), Min. 250 microns"
18,Flow Direction,Bi-directional (With preferred flow direction)
19,Internal Hardware,Stainless Steel A2-70 or A4-80 Bolts/Pins
20,Top Flange,ISO 5211 for actuator mounting
21,Working Temp,−10°C to +80°C (Standard water service)
Contact: Jorge Yang
Phone: +86-13588258503
E-mail: sales@fluvalve.com
Whatsapp:+86-13588258503
Add: Room 331, South Building,Building 1, No.3 Jinpeng Street, Sandun Town, Xihu District, Hangzhou City, Zhejiang Province
