ASTM A182 F316L Stainless Steel Spectacle Blind Flange / Figure 8 Flanges
A spectacle flange / figure-8 blank, is a ety 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. It 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.
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. is essentially a simplistic valve which fits in the line between two flanges and is bolted in place. One side of the Spectacle Blind is open (spacer) and the other side of the Spectacle Blind is blanked (blind or spade).
Equivalent Grades
STANDARD | WERKSTOFF NR. | UNS | JIS | BS | GOST | AFNOR | EN |
SS 316L | 1.4404 / 1.4435 | S31603 | SUS 316L | 316S11 / 316S13 | 03Ch17N14M3 / 03Ch17N14M2 | Z3CND17‐11‐02 / Z3CND18‐14‐03 | X2CrNiMo17-12-2 / X2CrNiMo18-14-3 |
Product Details
Forged and Plate Flanges
Products | Size | |
ASTM A182 SS 316L Slip-On Flanges | ASTM A182 SS 316L Threaded Flanges | Sizes 1/8″ – 36″ Raised Face or Flat Face |
ASTM A182 SS 316L Weld Neck Flanges | ASTM A182 SS 316L Socket Weld Flanges | |
ASTM A182 SS 316L Blind Flanges | ASTM A182 SS 316L Reducing Flanges | |
ASTM A182 SS 316L Lap Joint Flanges | ASTM A182 SS 316L Plate Flanges | |
ASTM A182 SS 316L Orifice Flanges | ASTM A182 SS 316L Forged Flanges | |
ASTM A182 SS 316L Ring Type Joint Flanges | ASTM A182 SS 316L Square Flanges |
SS 316L Flange Standards / Types And Pressure Class
ASME/ANSI B 16.5 | Welding Neck Flange, Slip on Flange, Blind Flange, High Hub Blind Flange, Socket Weld Flange, Lap Joint Flange, Threaded Flange, Ring Type Joint Flange |
PRESSURE CLASS | 150, 300, 400, 600, 900, 1500, 2500 |
ASME/ANSI B 16.47 | Welding Neck Flange, Blind Flange [Series A & B] |
PRESSURE CLASS | 75, 150, 300, 400, 600, 900 |
ASME/ANSI B 16.36 | Welding Neck Flange, Slip on Flange, Threaded Flange |
PRESSURE CLASS | 300, 400, 600, 900, 1500, 2500 |
BS 4504 SEC 3.1 | Welding Neck Flange, Hubbed Slip on Flange, Hubbed Threaded Flange, Lapped Pipe End Flange, Plate Flange, Loose Plate Flange, Loose Plate With Weld Neck Flange, Blank Flange |
PRESSURE CLASS | PN 2.5 TO PN 40 |
BS 4504[PART 1] | Welding Neck Flange, Hubbed Slip-On Hubbed Threaded, Plate Flange, Loose Plate With Weld On Plate Collar, Blank Flange |
PRESSURE CLASS | PN 2.5 TO PN 400 |
BS 1560 BOSS | Welding Neck Flange, Socket Welding Flange, Slip-On Flange, Blind Flange, Screwed Boss Flange, Lapped Flange |
PRESSURE CLASS | 150, 300, 400, 600, 900, 1500, 2500 |
BS10 | Welding Neck Flange, Plate Slip-On Flange, Screwed Boss Flange, Slip-On Boss Flange, Blind Flange |
TABLE | D, E, F, H |
DIN FLANGES | DIN 2527, 2566, 2573, 2576, 2641,2642, 2655, 2656, 2627, 2628, 2629, 2631, 2632, 2633, 2634, 2635, 2636, 2637,2638, 2673 |
PRESSURE CLASS | PN 6 TO PN 100 |
Application
Natural gas,chemical,petroleum,ship building,marine,paper making, metallurgy, electric, power, boiler , etc.
It is used usually for maintenance when it is required to isolate a section of pipe or isolate a device. Because this is a semi-permanent isolation it is very e and ety is often the mentality behind the use of a Spectacle Blind in maintenance operations.