Knife Gate Valve WB11

Stafsjö’s knife gate valve WB11 is bi-directional and can therefore be installed into a pipe system independent of pressure direction. Integrated flange gaskets makes it easy to install. WB11 has a full bore with no cavity which gives excellent flow characteristics, and this makes it suitable for fluids, sludge and liquids with solids in suspensions such as water, sewage and bio mass.

WB11 has a robust coated valve body in nodular iron. It is equipped with a gate in stainless steel, which has a polished edge in order to minimize friction and to lower required operation force. The valve is supplied with a sealing profile in Nitrile or EPDM, which is reinforced with a steel core. The gland box is equipped with Stafsjö’s box packing TwinPack™, to secure that no media reaches the surrounding environment. A box bottom scraper, which is standard from DN 200, prolongs the box packing braids’ service life. The valve is modular designed and it can easily be supplied with different types of actuators and accessories.

The WB11 valve is designed, manufactured, inspected and tested according to the European Pressure Equipment Directive (PED 97/23/EC) category I and II module A1. The valve is CE marked when it is applicable.

Other WB versions are the semi lugged WB available from DN 350 up to DN 1400 and the fully lugged WB14 available up to DN 600. For square flange connection we are able to supply WB11k with additional tapped holes for this or WB12 which has a square fully flanged valve body.

Main Dimensions

DNABCDEFGHJKLNOPQRWeight 7)
5050439086200592994651176292271494991283814196,5
65654610586200663244901316542521474921534075118,0
808046120862008934651313067727514447917642959810,0
10010052144862001013815481517123101466351747265312,5
12512556169862501154216381777523501375915751284616,5
150150561928625013046472720179429212955499554103919,5
20020060256151315155561866265818483217633247716111732,5
25025068307151315193657105033591457948,5
300300783541513152287531146372105967566,0
7) Weight in kg for valve equipped with hand wheel. Main dimensions are only for information. Contact Stafsjö for certified drawings.

Flange drilling according to EN 1092 PN10

Flange drilling information (mm)
DN506580100125150200250300
Outside flange diameter165185200220250285340395445
Bolt circle diameter125145160180210240295350400
Number of throughgoing bolts (○)4444444
Number of tapped hole/side (●)444444488
Bolt sizeM16M16M16M16M16M20M20M20M20
β°454522,522,522,522,522,51515
Screw lengths 8)121211151515162020
○ Throughgoing holes
● Tapped holes
8) Add the values with the thickness of the pipe flanges and the washers.
9) Pressures according to design data are not valid for valves with the special square WB11k drilling. Maximum working and differential pressure at 20°C for DN 150 – DN 200 is 4 bar.

Flange drilling WB11k 9)

EN 1092 PN10 and additional tapped holes for WB11k (mm)
DN150200
Number of extra tapped holes on each side44
Bolt sizeM12M12
l (mm)150180
Screw lengths 8) (mm)1618
8) Add the values with the thickness of the pipe flanges and the washers.
9) Pressures according to design data are not valid for valves with the special square WB11k drilling. Maximum working and differential pressure at 20°C for DN 150 – DN 200 is 4 bar.

Flange drilling according to ASME/ANSI B 16.5 Class 150

Flange drilling information (mm)
DN506580100125150200250300
Outside flange diameter152,4177,8190,5228,6254279,4342,9406,4482,6
Bolt circle diameter (mm)120,6139,7152,4190,5215,9241,3298,4361,9431,8
Number of throughgoing bolts (○)444444
Number of tapped hole/side (●)444444488
Bolt size (UNC)5/8-115/8-115/8-115/8-113/4-103/4-103/4-107/8-97/8-9
β°45454522.522.522.522.51515
Screw lengths 8)121211151515162020
○ Throughgoing holes
● Tapped holes
8) Add the values with the thickness of the pipe flanges and the washers.

Expert technical
knowledge

Contact us for expert technical advice with applications, grade selection and product working pressures.

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products

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