The Valve,safety Relief, cataloged under National Stock Number 4820-01-057-6792, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 27 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-057-6792 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Furnished Items and Quantity | 1 LOCKING DEVICE |
| Connection Style | PLAIN,OPTIONAL END(PIPE) ALL ENDS |
| Connection Type | THREADED INTERNAL PIPE ALL ENDS |
| Style Designator | STRAIGHT THRU NOTE: TO BE USED FOR VALVE BODIES OF ONE SECTION ONLY. |
| Material Document and Classification | QQ-S-764,TYPE 303-CANCELED FED SPEC SINGLE MATERIAL RESPONSE SEAT |
| Material Document and Classification | QQ-S-764,TYPE 303-CANCELED FED SPEC SINGLE MATERIAL RESPONSE BODY |
| Material Document and Classification | L-P-385,GRADE 2 ASSN STD SINGLE MATERIAL RESPONSE FLOW CONTROL DEVICE |
| Material Document and Classification | QQ-S-764,TYPE 303-CANCELED FED SPEC SINGLE MATERIAL RESPONSE STEM |
| Operating Pressure | 10500.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Adjustable Pressure Range | +3890.0 TO 7500.0 POUNDS PER SQUARE INCH LBS |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.250 INCHES ALL ENDS IN |
| Maximum Operating Temp | 250.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Disk Loading Method | SPRING |
| Media for Which Designed | NITROGEN, GASEOUS FIFTH RESPONSE |
| Media for Which Designed | GAS, NATURAL SECOND RESPONSE |
| Media for Which Designed | HELIUM THIRD RESPONSE |
| Media for Which Designed | AIR FIRST RESPONSE |
| Media for Which Designed | OIL, HYDRAULIC FOURTH RESPONSE |
| Material | STEEL BODY |
| Material | STEEL SEAT |
| Material | STEEL STEM |
| Material | PLASTIC POLYCHLOROTRIFLUOROETHYLENE FLOW CONTROL DEVICE |
| Thread Series Designator | NPT ALL ENDS |
| Valve Discharge Flow Rate | 500.0 CUBIC FEET PER MINUTE |
| 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 |
|---|---|
| 639AS1366-1 | 7/1 Vendor item drawing reference Naval Air Systems Command Managed Original Design Activity Not Material/parts Supplier |
| 5349T-2PP(L)-4500 | 3/2 Design control — primary reference U.S. Government activity |
NSN 4820-01-057-6792 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-01-057-6792: Flow Control Device: POPPET; Furnished Items and Quantity: 1 LOCKING DEVICE; Connection Style: PLAIN,OPTIONAL END(PIPE) ALL ENDS; Connection Type: THREADED INTERNAL PIPE ALL ENDS. 27 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.