The Valve,safety Relief, cataloged under National Stock Number 4820-01-447-9211, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Parker-Hannifin Corporation Dba Pneutronics Div Hydraulic Valve Division. Government technical data includes 13 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-447-9211 |
| Primary Part Number | 647B-1-1/8-28 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Parker-Hannifin Corporation Dba Pneutronics Div Hydraulic Valve Division |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Connection Style | PLAIN (PIPE) ALL ENDS |
| Connection Type | THREADED EXTERNAL PIPE ALL ENDS |
| Style Designator | ANGLE |
| Material Document and Classification | MIL-R-25897 CLASS 1 MIL SPEC SINGLE MATERIAL RESPONSE SEAT |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.125 INCHES ALL ENDS IN |
| Material | STEEL COMP 303 BODY |
| Material | RUBBER POLYMETHYLENE-PERFLUOROALKYLENE CLASS FKM SEAT |
| Material | STEEL COMP 303 OR STEEL COMP 416 FLOW CONTROL DEVICE |
| Thread Series Designator | ANPT ALL ENDS |
| Opening Pressure Setting | 8.0 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 |
| Part Number | Manufacturer |
|---|---|
| 647B-1-1/8-28 PRIMARY | Parker-Hannifin Corporation Dba Pneutronics Div Hydraulic Valve Division (USA) |
| Reference | Meaning |
|---|---|
| 4820PL1792809 | 6/9 Informative reference only Jednolity Indeks Materialowy - Uniform Material Index |
| 3150143-2 | 5/9 Secondary reference Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier |
| 647B-1-1/8-28 | 5/9 Secondary reference U.S. Government activity |
| 3150143 | 7/1 Vendor item drawing reference Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier |
NSN 4820-01-447-9211 is a Valve,safety Relief, manufactured by Parker-Hannifin Corporation Dba Pneutronics Div Hydraulic Valve Division, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-447-9211 has 1 manufacturer part number on file: 647B-1-1/8-28 (Parker-Hannifin Corporation Dba Pneutronics Div Hydraulic Valve Division).
Key specifications for 647B-1-1/8-28: Flow Control Device: POPPET; Connection Style: PLAIN (PIPE) ALL ENDS; Connection Type: THREADED EXTERNAL PIPE ALL ENDS; Style Designator: ANGLE. 13 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.