The Valve,safety Relief, cataloged under National Stock Number 4820-01-345-9972, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 12 specifications, cited from the U.S. Government catalog. 7 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 4820-01-345-9972 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Connection Style | PLAIN,OPTIONAL END(PIPE) ALL ENDS |
| Criticality Code Justification | FEAT |
| Connection Type | THREADED INTERNAL PIPE ALL ENDS |
| Style Designator | ANGLE |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.125 INCHES ALL ENDS IN |
| Disk Loading Method | SPRING |
| Material | STEEL CORROSION RESISTING BODY |
| Thread Series Designator | NPT ALL ENDS |
| Opening Pressure Setting | 110.0 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 | F |
| Reference | Meaning |
|---|---|
| 1455AS204-1 | C/1 Advisory reference — outside the item-of-supply concept Naval Air Systems Command Managed Original Design Activity Not Material/parts Supplier |
| 1-3092-1 | 5/9 Secondary reference Parker-Hannifin Corporation Dba Pneutronics Div Hydraulic Valve Division |
| 1455AS204 | 7/2 Vendor item drawing reference Naval Air Systems Command Managed Original Design Activity Not Material/parts Supplier |
| 631B-3-1/8-28 | 5/9 Secondary reference Parker-Hannifin Corporation Dba Pneutronics Div Hydraulic Valve Division |
| 631B-3-1/8-T | 5/9 Secondary reference U.S. Government activity |
| 631B-3-1/8-28 | 5/9 Secondary reference U.S. Government activity |
| VRVD-125-B-T-110-X | 3/9 Design control — primary reference U.S. Government activity |
NSN 4820-01-345-9972 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
1 possible match (shared part number, not a government interchangeability claim): 4320-01-597-8645. Verify interchangeability with system specifications before substitution.
Key specifications for 4820-01-345-9972: Flow Control Device: DISK; Connection Style: PLAIN,OPTIONAL END(PIPE) ALL ENDS; Criticality Code Justification: FEAT; Connection Type: THREADED INTERNAL PIPE ALL ENDS. 12 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.