The Valve,safety Relief, cataloged under National Stock Number 4820-00-400-6785, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 30 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 4820-00-400-6785 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Recess Nominal Depth | 0.125 INCHES FIRST END IN |
| Flange Shape | RECTANGULAR WITH HOLES SECOND END |
| Flange Shape | RECTANGULAR WITH HOLES FIRST END |
| Renewable Seat Ring Type | PRESSED-IN |
| Flange Face Design | PLAIN SECOND END |
| Flange Face Design | RECESSED STRAIGHT FIRST END |
| Nominal Length | 2.400 INCHES FIRST END IN |
| Nominal Length | 3.765 INCHES SECOND END IN |
| Bolt Circle Nominal Diameter | 2.313 INCHES SECOND END IN |
| Connection Type | FLANGE SECOND END |
| Connection Type | FLANGE FIRST END |
| Style Designator | ANGLE FLANGED ENDS |
| Bolt Hole Nominal Diameter | 0.313 INCHES FIRST END IN |
| Bolt Hole Nominal Diameter | 0.532 INCHES SECOND END IN |
| Valve Size | 1.000 INCHES IN |
| Bonnet Type | PACKING RETAINING |
| Center to Center Nominal Distance Between Bolt Holes Along Width | 1.625 INCHES FIRST END IN |
| Second Connection Face to Centerline Distance | 1.562 INCHES IN |
| Disk Loading Method | SPRING |
| Bolt Hole Quantity | 4 FIRST END |
| Nominal Width | 1.750 INCHES SECOND END IN |
| Nominal Width | 2.400 INCHES FIRST END IN |
| Center to Center Nominal Distance Between Bolt Holes Along Length | 1.625 INCHES FIRST END IN |
| First Connection Face to Centerline Distance | 1.375 INCHES IN |
| Material | STEEL FLOW CONTROL DEVICE |
| Material | IRON CAST BODY |
| Material | COPPER ALLOY SEAT |
| Valve Operation Method | AUTOMATIC |
| Nominal Thickness | 1.125 INCHES SECOND END IN |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| 998-0510-09 | 3/9 Design control — primary reference Copeland Corp |
| 510-0063-00 | 5/9 Secondary reference Copeland Corp |
NSN 4820-00-400-6785 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
1 possible match (shared part number, not a government interchangeability claim): 6130-01-560-9253. Verify interchangeability with system specifications before substitution.
Key specifications for 4820-00-400-6785: Flow Control Device: POPPET; Recess Nominal Depth: 0.125 INCHES FIRST END IN; Flange Shape: RECTANGULAR WITH HOLES SECOND END; Flange Shape: RECTANGULAR WITH HOLES FIRST END. 30 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.