A spectacle flange (figure-8 blank), is a safety device used to isolate a section of line or piece of equipment when the line or equipment needs to be inspected or removed from service. It is different than a valve in that the blind is a permanent or long term isolation device.
A spectacle flange (figure-8 blank) is machined from a single piece of metal that is cut to match the pipe size, fit between two pipe flanges and requires an additional gasket when it is installed. Also, the bolts will need to be lengthened depending on what piping class and size blind is used. The thickness of the spectacle blind is specified based on the line pressure and pipe size.
Size: Spectacle flange:1″- 24″
DN25 - DN600
America Series: Class 150 ,Class 300, Class 600, Class 900A ,Class 1500,Class 2500.
Europe Series: PN2.5,PN6,PN10,PN16,PN25,PN40,PN63,PN100,PN160,PN250,PN320,PN400.
Stainless Steel: ASTM A 182, A 240
Grade: F304, 304L, 304H, 316, 316L, 316Ti, 310, 310S, 321, 321H, 317, 347, 347H,904L, Duplex Stainless Steel UNS S31803, 2205, Super Duplex Stainless Steel UNS S32750
Carbon Steel: ASTM A 105, ASTM A 181
Alloy Steel: ASTM A 182, GR F1, F11, F22, F5, F9, F91
Nickel Alloys: Monel 400 & 500, Inconel 600 & 625, Incolloy 800, 825, Hastelloy C22,C276
Copper Alloys: Copper, Brass & Gunmetal
Flange Facing Types OF spectacle flange (figure-8 blank):
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)
ANSI: ANSI B16.5, ANSI B16.47, MSS SP44, ANSI B16.36, ANSI B16.48
DIN: DIN2527, DIN2566, DIN2573, DIN2576, DIN2641, DIN2642, DIN2655, DIN2656, DIN2627, DIN2628, DIN2629, DIN 2631, DIN2632, DIN2633, DIN2634, DIN2635, DIN2636, DIN2637, DIN2638, DIN2673
B.S: BS4504 , BS4504, BS1560, BS10
Application for spectacle flange (figure-8 blank):
Natural gas,chemical,petroleum,ship building,marine,paper making, metallurgy, electric, power, boiler , etc.
Yaang Pipe Industry, as a first class manufacturer of spectacle flange (figure-8 blank) in China, supplys a variety of stainless steel flanges to satisfy our customers’ specifica 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 threaded flanges all are purchased from big steel companies which can make sure the material in a high quality.