The Valve,safety Relief, cataloged under National Stock Number 4820-01-052-5166, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 26 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 4820-01-052-5166 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Renewable Seat Ring Type | PRESSED-IN |
| Connection Style | PLAIN (TUBE) FIRST END |
| Connection Type | THREADED EXTERNAL TUBE FIRST END |
| Style Designator | STRAIGHT THRU NOTE: TO BE USED FOR VALVE BODIES OF ONE SECTION ONLY. |
| Material Document and Classification | QQ-S-764,TYPE 303SE-CANCELED FED SPEC SINGLE MATERIAL RESPONSE BODY |
| Material Document and Classification | QQ-S-764,TYPE 303SE-CANCELED FED SPEC SINGLE MATERIAL RESPONSE FLOW CONTROL DEVICE |
| Material Document and Classification | QQ-S-764,TYPE 303SE-CANCELED FED SPEC SINGLE MATERIAL RESPONSE STEM |
| Operating Pressure | 200.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND FIRST END |
| Nominal Thread Size | 0.562 INCHES FIRST END IN |
| Maximum Operating Temp | 280.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Disk Loading Method | SPRING |
| Media for Which Designed | HELIUM FIFTH RESPONSE |
| Media for Which Designed | FUEL/OIL, HYDROCARBON FOURTH RESPONSE |
| Media for Which Designed | ALCOHOL, ETHYL SECOND RESPONSE |
| Media for Which Designed | AMMONIA, GASEOUS THIRD RESPONSE |
| Media for Which Designed | AIR FIRST RESPONSE |
| Thread Class | 3A FIRST END A |
| Material | RUBBER BUTADIENE-ACRYLONITRILE CLASS NBR SEAT |
| Material | STEEL COMP 303 BODY |
| Material | STEEL COMP 303SE FLOW CONTROL DEVICE |
| Material | STEEL COMP 303SE STEM |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) FIRST END |
| Opening Pressure Setting | 7.0 POUNDS PER SQUARE INCH LBS |
| 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 |
|---|---|
| 559TGD7 | C/1 Advisory reference — outside the item-of-supply concept U.S. Government activity |
| 559T-6D-7 | 3/2 Design control — primary reference U.S. Government activity |
NSN 4820-01-052-5166 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-01-052-5166: Flow Control Device: POPPET; Renewable Seat Ring Type: PRESSED-IN; Connection Style: PLAIN (TUBE) FIRST END; Connection Type: THREADED EXTERNAL TUBE FIRST END. 26 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.