The Valve,safety Relief, cataloged under National Stock Number 4820-00-237-5791, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 21 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 4820-00-237-5791 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Renewable Seat Ring Type | THREADED |
| Nominal Pipe Size Accommodated | 1.000 INCHES FIRST END IN |
| Connection Style | SOCKET WITH BRAZING RING FIRST END |
| Criticality Code Justification | ZZZY |
| Connection Type | UNTHREADED INTERNAL PIPE FIRST END |
| Style Designator | ANGLE |
| Operating Pressure | 1500.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Adjustable Pressure Range | +5.0 TO 1500.0 POUNDS PER SQUARE INCH LBS |
| Features Provided | PRESSURE TIGHT OUTLET SIDE |
| Bonnet Type | INSIDE SPRING |
| Maximum Operating Temp | 180.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Disk Loading Method | SPRING |
| Bonnet Attachment Method | BOLTED |
| Media for Which Designed | WATER, FRESH SINGLE RESPONSE |
| Material | NICKEL ALLOY 400 SEAT |
| Material | COPPER ALLOY 922 BODY |
| Material | NICKEL ALLOY 400 STEM |
| Opening Pressure Setting | 185.0 POUNDS PER SQUARE INCH LBS |
| Valve Operation Method | HYDRAULIC |
| Reference Number Differentiating Characteristics | MATERIAL WILL BE IN ACCORDANCE WITH SHIPS PARTS CONTROL CENTER ACTIVITY HX QUALITY CONTROL,MANUFACTURING AND TESTING SPECIFICATIONS |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL F — Mutilate — Cut |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | C |
| Reference | Meaning |
|---|---|
| E8720PM41M | 3/1 Design control — primary reference Anderson Greenwood Lp Dba Anderson Greenwood Crosby |
| 8720M0D | 5/1 Secondary reference Anderson Greenwood Lp Dba Anderson Greenwood Crosby |
NSN 4820-00-237-5791 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-00-237-5791: Flow Control Device: DISK; Renewable Seat Ring Type: THREADED; Nominal Pipe Size Accommodated: 1.000 INCHES FIRST END IN; Connection Style: SOCKET WITH BRAZING RING FIRST END. 21 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.
NSN 4820-00-237-5791 has DEMIL Code F. Demilitarization may be required before disposal or transfer to non-military entities.
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.