The Valve,safety Relief, cataloged under National Stock Number 4820-01-312-5963, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Evergreen Midwest Co. Government technical data includes 17 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-312-5963 |
| Primary Part Number | PRV9434T450 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Evergreen Midwest Co |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Connection Style | PLAIN (PIPE) ALL ENDS |
| Connection Type | THREADED EXTERNAL PIPE ALL ENDS |
| Style Designator | STRAIGHT THRU |
| Operating Pressure | 400.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Bonnet Type | INSIDE SCREW |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.500 INCHES ALL ENDS IN |
| Maximum Operating Temp | 125.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Bonnet Attachment Method | THREADED |
| Media for Which Designed | OXYGEN, GASEOUS SECOND RESPONSE |
| Media for Which Designed | NITROGEN, LIQUID FIRST RESPONSE |
| Media for Which Designed | OXYGEN, LIQUID THIRD RESPONSE |
| Material | COPPER ALLOY BODY |
| Thread Series Designator | NPT ALL ENDS |
| Opening Pressure Setting | 450.0 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 |
|---|---|
| PRV9434T450 PRIMARY | Evergreen Midwest Co (USA) |
| Reference | Meaning |
|---|---|
| B-9434N450 | 5/9 Secondary reference Rego Co a Marmon Group Co |
| 8772423 | 5/9 Secondary reference Libby Power Systems, Llc |
NSN 4820-01-312-5963 is a Valve,safety Relief, manufactured by Evergreen Midwest Co, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-312-5963 has 1 manufacturer part number on file: PRV9434T450 (Evergreen Midwest Co).
Key specifications for PRV9434T450: Flow Control Device: DISK; Connection Style: PLAIN (PIPE) ALL ENDS; Connection Type: THREADED EXTERNAL PIPE ALL ENDS; Style Designator: STRAIGHT THRU. 17 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.