Figure 8 Blank or Spectacle Blind

Figure 8 Blanks or Spectacle Blinds are critical components used in pipeline systems to isolate sections of the pipe for maintenance or to safely control the flow. Below are the full specifications, grades, and standards associated with these components.Figure 8 Blank / Spectacle Blind Specifications1. Overview• Design: A combination of a solid blind plate and a spacer plate, typically used in pipeline systems to provide a reliable means of isolation.• Function: Allows for the complete closure or opening of a pipeline section.2. DimensionsThe dimensions of Figure 8 Blanks or Spectacle Blinds vary based on the pipe size and pressure class. Standard dimensions are usually given in relation to:• Nominal Pipe Size (NPS)• Pressure Class (e.g., Class 150, 300, 600, 900, 1500, 2500)• Flange Standards (e.g., ASME B16.5, B16.48, MSS SP-44)3. Material GradesSpectacle Blinds can be made from various materials depending on the service conditions. Common materials include:1. Carbon Steel: Grade: ASTM A105, ASTM A516 Gr 60/702. Stainless Steel:o Grades: ASTM A182 F304 (1.4301), ASTM A182 F316 (1.4401)3. Alloy Steel:o Grade: ASTM A335 P11, P22, P914. Duplex Stainless Steel:o Grades: ASTM A182 F51 (UNS S31803), ASTM A182 F60 (UNS S32205)5. Super Duplex Stainless Steel:o Grades: ASTM A182 F53 (UNS S32750), ASTM A182 F55 (UNS S32760)6. Nickel-Based Alloys:o Grades: Hastelloy C-276, Inconel 6254. Pressure RatingsSpectacle blinds are rated according to pressure classes that reflect their ability to withstand various internal pressures. Common pressure classes include:• Class 150: Suitable for low-pressure applications.• Class 300: Medium pressure applications.• Class 600: High-pressure applications.• Class 900: Very high-pressure applications.• Class 1500: Extremely high-pressure applications.• Class 2500: Ultra-high-pressure applications.5. Standards• ASME B16.5/B16.48 Provides dimensions, materials, and pressure-temperature ratings for flanges and fittings.• MSS SP-44: Specification for spectacle blinds and other pipe fittings, including detailed dimensions and pressure ratings.SPECFICATIONS:• Manufacturing Range: DN 15 (1/2”) to DN 1500 (60”)• Rating/Class: 150/300/600/900/1500/2500 and SCH 5/5S/10/10S/20/40/STD/60/80/XS/100/120/140/160/XXS etc.• Dimension Standard: ANSI/ASME B16.48/B16.5, etc.Material Type: HIGH NICKEL ALLOYS: Inconel 600, Inconel 625, Inconel 718, Inconel 800, Inconel 825, Monel 400, Monel K-500, Hastelloy C-276, Hastelloy B-2, Hastelloy C-22, Titanium Gr 2, Titanium Gr 5CARBON/ALLOY STEEL: ASTM/ASME A105/105N, ASTM / ASME A182, ASTM / ASME A335 GR F1, F5, F9, F11, F12, F22, F23, F91, ASTM A516 GR 60/70, ASTM A516 GR 60, ASTM A516 GR 70LTCS: ASTM/ASME A350 LF2, ASME/ASTM A694 F42, F46, F52, F60, F65, F70STAINLESS STEEL: ASTM A182 F304 (1.4301), F304L (1.4306/1.4307), F316 (1.4401), F316L (1.4404), F304H, F309S, F309H, F310S, F310H, F316TI, F316H, F316LN, F317, F317L, F321, F321H, F11, F22, F91, F347, F347H, F904L,  UNS S 31254 (1.4547) DUPLEX STEEL: Duplex (S32205 / S31803) X2CrNiMoN22-5-3 (1.4462), S32750 (EN/DIN 1.4410, X2CrNiMoN25-7-4), S32760 (1.4501, X2CrNiMoCuWN 25-7-4)HIGH NICKEL ALLOYS: Inconel 600, Inconel 625, Inconel 718, Inconel 800, Inconel 825, Monel 400, Monel K-500, Hastelloy C-276, Hastelloy B-2, Hastelloy C-22, Titanium Gr 2, Titanium Gr 5COPPER NICKEL ALLOYS: CUNI 90/10 (C70600), CUNI 70/30 (C71500)