The Valve,safety Relief, cataloged under National Stock Number 4820-01-191-6091, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 28 specifications, cited from the U.S. Government catalog. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-191-6091 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Flange Shape | ROUND WITH HOLES ALL ENDS |
| Flange Face Design | PLAIN ALL ENDS |
| Bolt Circle Nominal Diameter | 5.500 INCHES ALL ENDS IN |
| Connection Type | FLANGE ALL ENDS |
| Style Designator | ANGLE |
| Material Document and Classification | QQ-N-288 FED SPEC SINGLE MATERIAL RESPONSE SEAT |
| Material Document and Classification | ASTM B-61 ASSN STD SINGLE MATERIAL RESPONSE BODY |
| Material Document and Classification | ASTM B-164 ASSN STD SINGLE MATERIAL RESPONSE STEM |
| Material Document and Classification | ASTM B-164 ASSN STD SINGLE MATERIAL RESPONSE FLOW CONTROL DEVICE |
| Bolt Hole Nominal Diameter | 0.562 INCHES ALL ENDS IN |
| Operating Pressure | 150.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Valve Size | 3.000 INCHES IN |
| Adjustable Pressure Range | +20.0 TO 24.0 POUNDS PER SQUARE INCH LBS |
| Bonnet Type | INSIDE SPRING |
| Maximum Operating Temp | 150.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Second Connection Face to Centerline Distance | 5.500 INCHES IN |
| Nondefinitive Spec/std Data | B GRADE |
| Nominal Outside Diameter | 6.625 INCHES ALL ENDS IN |
| Disk Loading Method | SPRING |
| Bolt Hole Quantity | 8 ALL ENDS |
| Bonnet Attachment Method | BOLTED |
| First Connection Face to Centerline Distance | 6.000 INCHES IN |
| Material | COPPER ALLOY BODY |
| Material | NICKEL ALLOY STEM |
| Material | NICKEL ALLOY FLOW CONTROL DEVICE |
| Material | NICKEL ALLOY SEAT |
| Valve Operation Method | AUTOMATIC |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| 20218-004-41M | 5/9 Secondary reference Anderson Greenwood Lp Dba Anderson Greenwood Crosby |
| 20218 | D/9 Drawing number reference only Anderson Greenwood Lp Dba Anderson Greenwood Crosby |
| MIL-DTL-24332 | 4/1 Identification reference U.S. Government activity |
| MIL-V-24332 | 5/9 Secondary reference U.S. Government activity |
NSN 4820-01-191-6091 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-01-191-6091: Flow Control Device: DISK; Flange Shape: ROUND WITH HOLES ALL ENDS; Flange Face Design: PLAIN ALL ENDS; Bolt Circle Nominal Diameter: 5.500 INCHES ALL ENDS IN. 28 specifications are documented in the U.S. Government catalog.
No hazard code in the DLA record (HMIC N). Hazard information on this page is shown exactly as it appears in the DLA record.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.