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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.

Print Product Data Sheet

Main Dimensions

DN A B C D E F G H J K L N O P Q R Weight 7)
50 50 43 90 86 200 59 299 465 117 629 227 149 499 128 381 419 6,5
65 65 46 105 86 200 66 324 490 131 654 252 147 492 153 407 511 8,0
80 80 46 120 86 200 89 346 513 130 677 275 144 479 176 429 598 10,0
100 100 52 144 86 200 101 381 548 151 712 310 146 635 17 472 653 12,5
125 125 56 169 86 250 115 421 638 177 752 350 137 591 57 512 846 16,5
150 150 56 192 86 250 130 464 727 201 794 292 129 554 99 554 1039 19,5
200 200 60 256 151 315 155 561 866 265 818 483 217 633 247 716 1117 32,5
250 250 68 307 151 315 193 657 1050 335 914 579 – – – – – 48,5
300 300 78 354 151 315 228 753 1146 372 1059 675 – – – – – 66,0
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)
DN 50 65 80 100 125 150 200 250 300
Outside flange diameter 165 185 200 220 250 285 340 395 445
Bolt circle diameter 125 145 160 180 210 240 295 350 400
Number of throughgoing bolts (○) – – 4 4 4 4 4 4 4
Number of tapped hole/side (●) 4 4 4 4 4 4 4 8 8
Bolt size M16 M16 M16 M16 M16 M20 M20 M20 M20
β° 45 45 22,5 22,5 22,5 22,5 22,5 15 15
Screw lengths 8) 12 12 11 15 15 15 16 20 20
○ 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)
DN 150 200
Number of extra tapped holes on each side 4 4
Bolt size M12 M12
l (mm) 150 180
Screw lengths 8) (mm) 16 18
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)
DN 50 65 80 100 125 150 200 250 300
Outside flange diameter 152,4 177,8 190,5 228,6 254 279,4 342,9 406,4 482,6
Bolt circle diameter (mm) 120,6 139,7 152,4 190,5 215,9 241,3 298,4 361,9 431,8
Number of throughgoing bolts (○) – – – 4 4 4 4 4 4
Number of tapped hole/side (●) 4 4 4 4 4 4 4 8 8
Bolt size (UNC) 5/8-11 5/8-11 5/8-11 5/8-11 3/4-10 3/4-10 3/4-10 7/8-9 7/8-9
β° 45 45 45 22.5 22.5 22.5 22.5 15 15
Screw lengths 8) 12 12 11 15 15 15 16 20 20
○ 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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