American standard spectacle blind flange for flow isolation. ASME B16.5. NPS 1/2"-24", Class 150-2500.Permanently installed in the pipeline for safe isolation.
The ASME B16.5 Spectacle Blind Flange (SB) is a solid metal disc (blind) or spacer-r-spacer assembly installed between two flanges in a pipeline. The "spectacle" refers to the shape of the assembly which consists of a solid blind section (to block flow) and a spacer section (to allow flow) connected by a center bar. This design allows safe isolation of process sections without removing the flange assembly from the pipeline.
JIAJI FORGING manufactures Spectacle Blind flanges in austenitic stainless steel, duplex & super duplex stainless steel, and nickel alloys to ASME B16.5 standards.
| Parameter | Specification |
|---|---|
| Standard | ASME B16.5 (NPS 1/2"-24") |
| Size Range | NPS 1/2" - NPS 24" (DN15 - DN600) |
| Pressure Rating | Class 150 / 300 / 400 / 600 / 900 / 1500 / 2500 |
| Type | Spectacle Blind (SB), Spade, Spacer |
| Materials | 304/304L (F8/F8A), 316/316L (F8/F8A), 321 (F8C), 347 (F8D), 310S, 904L, 2205 (F51), 2507 (F53), Inconel 625, Inconel 825, Hastelloy C276, Monel 400 |
| Surface | Anti-rust oil, black, galvanized, painted |
| UNS / AISI | ASTM |
|---|---|
| 304 / 304L | A182 F8 / F8A |
| 316 / 316L | A182 F8 / F8A |
| 321 | A182 F8C |
| 347 | A182 F8D |
| 310S | A182 F310 |
| 904L | A182 F904L |
| UNS | ASTM |
|---|---|
| S31803 (2205) | A182 F51 |
| S32205 (2205) | A182 F51 |
| S32750 (2507) | A182 F53 |
| S32760 | A182 F55 |
| UNS / Alloy | ASTM |
|---|---|
| N06625 (Inconel 625) | A182 F65 |
| N08825 (Incoloy 825) | - |
| N10276 (Hastelloy C276) | - |
| N04400 (Monel 400) | - |
Per ASME B16.5, each spectacle blind is permanently marked with: Manufacturer / Material / Pressure Class / Size / Heat No.
Example: JIAJI · F316 · SB · 6" · CL300 · BATCH-2024
Thickness calculated per ASME Section VIII Div.1 for full pressure containment. Optional: NACE MR0175, 3.1 / 3.2 inspection certificates (EN 10204) available upon request.
ASME B16.5 Blind Flange. Full bore closure. NPS 1/2"-24". Class 150-2500.
View Details ->
