A spectacle blind – also known as a figure-8 blind – is generally a piece of metal that is cut to fit between two pipe flange and usually sandwiched between two gaskets. A spectacle blind is often made from two metal discs that are attached to each other by a small section of steel. The shape is similar to a pair of glasses or “spectacles” – hence the name spectacle blind. One end of the blind will have an opening to allow flow through the pipe during operation and the other end is solid to block flow during maintenance. They are generally installed as a permanent device to separate process piping systems.(Know more about Spectacle blind flange)
America Series:Class 150 ,Class 300, Class 600, Class 900A ,Class 1500,Class 2500.
Flange Facing Types
America Series:Flat face(FF),Raised face(RF),Tongue(T),Groove(G),Female(F),Male(M),Ring type joints face(RJ/RTJ)
Europe Series:Type A(Flat Face),Type B(Raised Face),Type C(Tongue),Type D(Groove),Type E(Spigot),Type F(Recess),Type G(O-Ring Spigot),Type H(O-Ring Groove)
Stainless steel: ASTM/ASME A182 F304-304L-304H-304LN-304N
ASTM/ASME A182 F316-316L-316H-316LN-316N-316Ti
ASTM/ASME A182 F321-321H, F347-347H, F310-310H, F904-904H
ASME /ANSI B16.48
MSS SP 44
BS1560,BS 4504,BS 10.
AFNOR NF E29-200-1
UNI 2276. UNI 2277.UNI 2278 .UNI 6089 .UNI 6090
Application for Spectacle flanges
Natural gas,chemical,petroleum,ship building,marine,paper making, metallurgy, electric, power, boiler , etc.
Hebei Haihao Group, as a first class manufacturer of spectacle flange (figure 8 blind flange) in China,supply a variety of steel flanges to satisfy our customers’ specific requirements,which include different size,different schedule,different pressure and different finish faces. Our products are produced strictly according to the required standard. Our raw material for spectacle flange (figure 8 blind flange) all are purchased from big steel companies which can make sure the material in a high quality.