The Valve,safety Relief, cataloged under National Stock Number 4820-00-973-9100, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 30 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-973-9100 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Nominal Pipe Size Accommodated | 0.500 INCHES SECOND END IN |
| Nominal Pipe Size Accommodated | 1.000 INCHES FIRST END IN |
| Connection Style | PLAIN,OPTIONAL END(PIPE) FIRST END |
| Connection Style | PLAIN (PIPE) SECOND END |
| Connection Type | THREADED INTERNAL PIPE FIRST END |
| Connection Type | THREADED EXTERNAL PIPE SECOND END |
| Style Designator | ANGLE |
| Operating Pressure | 2000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Features Provided | BONNET PACKING AND PRESSURE TIGHT OUTLET SIDE |
| Bonnet Type | INSIDE SPRING |
| Thread Direction | RIGHT-HAND SECOND END |
| Thread Direction | RIGHT-HAND FIRST END |
| Nominal Thread Size | 0.500 INCHES SECOND END IN |
| Nominal Thread Size | 1.000 INCHES FIRST END IN |
| Maximum Operating Temp | 200.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Disk Loading Method | SPRING |
| Bonnet Attachment Method | THREADED |
| Media for Which Designed | WATER-OIL-GAS SINGLE RESPONSE |
| Thread Quantity Per Inch | 14 SECOND END |
| Thread Quantity Per Inch | 11-1/2 FIRST END |
| Material | STEEL BODY |
| Material | STEEL CORROSION RESISTING FLOW CONTROL DEVICE |
| Material | STEEL CORROSION RESISTING SEAT |
| Material | STEEL CORROSION RESISTING STEM |
| Thread Series Designator | NPT SECOND END |
| Thread Series Designator | NPT FIRST END |
| Opening Pressure Setting | 525.0 POUNDS PER SQUARE INCH LBS |
| Valve Discharge Flow Rate | 24.8 GALLONS 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 |
|---|---|
| 1975C | 3/9 Design control — primary reference Dresser, Inc. Dba Dresser Equipment Group Div Industrial Valve Operations, Dresse |
NSN 4820-00-973-9100 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
1 possible match (shared part number, not a government interchangeability claim): 5330-01-341-5507. Verify interchangeability with system specifications before substitution.
Key specifications for 4820-00-973-9100: Flow Control Device: POPPET; Nominal Pipe Size Accommodated: 0.500 INCHES SECOND END IN; Nominal Pipe Size Accommodated: 1.000 INCHES FIRST END IN; Connection Style: PLAIN,OPTIONAL END(PIPE) FIRST END. 30 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.