The Valve,safety Relief, cataloged under National Stock Number 4820-00-447-9787, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Progress Rail Locomotive Inc. Dba Progress Rail Switching Services Llc. Government technical data includes 21 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through both NSN and commercial part number lookups. 7 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-447-9787 |
| Primary Part Number | 8077201 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Progress Rail Locomotive Inc. Dba Progress Rail Switching Services Llc |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Flange Shape | RECTANGULAR WITH HOLES FIRST END |
| Renewable Seat Ring Type | THREADED |
| Flange Face Design | PLAIN FIRST END |
| Nominal Length | 4.250 INCHES FIRST END IN |
| Connection Type | FLANGE FIRST END |
| Style Designator | ANGLE |
| Bolt Hole Nominal Diameter | 0.562 INCHES FIRST END IN |
| Bonnet Type | INSIDE SCREW |
| Center to Center Nominal Distance Between Bolt Holes Along Width | 3.000 INCHES ALL ENDS IN |
| Disk Loading Method | SPRING |
| Bolt Hole Quantity | 4 FIRST END |
| Bonnet Attachment Method | THREADED |
| Nominal Width | 4.250 INCHES FIRST END IN |
| Center to Center Nominal Distance Between Bolt Holes Along Length | 3.000 INCHES ALL ENDS IN |
| Material | STEEL FLOW CONTROL DEVICE |
| Material | STEEL STEM |
| Material | IRON CAST BODY |
| Material | IRON CAST SEAT |
| Valve Operation Method | AUTOMATIC |
| Nominal Thickness | 2.562 INCHES FIRST 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 |
| Part Number | Manufacturer |
|---|---|
| 8077201 PRIMARY | Progress Rail Locomotive Inc. Dba Progress Rail Switching Services Llc (USA) |
| Reference | Meaning |
|---|---|
| 8077201 | 3/9 Design control — primary reference General Motors Corp Electro-Motive Div |
| 8075306PC8069308 | C/1 Advisory reference — outside the item-of-supply concept General Motors Corp |
| 8077201 | 5/9 Secondary reference General Motors Corp |
| 8069308 | C/1 Advisory reference — outside the item-of-supply concept General Motors Corp |
| 8069308 | C/1 Advisory reference — outside the item-of-supply concept General Motors Corp Electro-Motive Div |
| 8075305PC8069308 | C/1 Advisory reference — outside the item-of-supply concept General Motors Corp |
| 8075307PC8069308 | C/1 Advisory reference — outside the item-of-supply concept General Motors Corp |
NSN 4820-00-447-9787 is a Valve,safety Relief, manufactured by Progress Rail Locomotive Inc. Dba Progress Rail Switching Services Llc, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-00-447-9787 has 1 manufacturer part number on file: 8077201 (Progress Rail Locomotive Inc. Dba Progress Rail Switching Services Llc).
Key specifications for 8077201: Flow Control Device: DISK; Flange Shape: RECTANGULAR WITH HOLES FIRST END; Renewable Seat Ring Type: THREADED; Flange Face Design: PLAIN FIRST END. 21 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.