The Valve,safety Relief, cataloged under National Stock Number 4820-01-320-8857, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Dante Valve Company. Government technical data includes 18 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-320-8857 |
| Primary Part Number | D50FF-05 1/2IN. |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Dante Valve Company |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Flange Shape | ROUND ALL ENDS |
| Flange Face Design | PLAIN ALL ENDS |
| Connection Type | FLANGE ALL ENDS |
| Style Designator | ANGLE FLANGED ENDS |
| Operating Pressure | 150.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Valve Size | 0.500 INCHES IN |
| Adjustable Pressure Range | +45.0 TO 75.0 POUNDS PER SQUARE INCH LBS |
| Second Connection Face to Centerline Distance | 3.672 INCHES IN |
| Nominal Outside Diameter | 3.562 INCHES ALL ENDS IN |
| Media for Which Designed | LIQUID SINGLE RESPONSE |
| First Connection Face to Centerline Distance | 3.672 INCHES IN |
| Material | BRONZE BODY |
| Material | NICKEL ALLOY FLOW CONTROL DEVICE |
| Material | NICKEL ALLOY SEAT |
| Material | STEEL CORROSION RESISTING STEM |
| Valve Operation Method | AUTOMATIC |
| Nominal Thickness | 0.375 INCHES ALL ENDS IN |
| 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 |
|---|---|
| D50FF-05 1/2IN. PRIMARY | Dante Valve Company (USA) |
| Reference | Meaning |
|---|---|
| D50FF-05 1/2IN. | 3/9 Design control — primary reference Danco Valve Company |
NSN 4820-01-320-8857 is a Valve,safety Relief, manufactured by Dante Valve Company, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-320-8857 has 1 manufacturer part number on file: D50FF-05 1/2IN. (Dante Valve Company).
Key specifications for D50FF-05 1/2IN.: Flow Control Device: DISK; Flange Shape: ROUND ALL ENDS; Flange Face Design: PLAIN ALL ENDS; Connection Type: FLANGE ALL ENDS. 18 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.