The Valve,safety Relief, cataloged under National Stock Number 4820-01-307-9309, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Emerson Automation Solutions Final Control Us Lp Div Navy Product Team. Government technical data includes 27 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 5 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-307-9309 |
| Primary Part Number | 20040R51SS |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Emerson Automation Solutions Final Control Us Lp Div Navy Product Team |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Flange Shape | ROUND WITH HOLES ALL ENDS |
| Flange Face Design | RAISED STRAIGHT ALL ENDS |
| Bolt Circle Nominal Diameter | 6.625 INCHES SECOND END IN |
| Bolt Circle Nominal Diameter | 7.500 INCHES FIRST END IN |
| Connection Type | FLANGE ALL ENDS |
| Style Designator | ANGLE FLANGED ENDS |
| Bolt Hole Nominal Diameter | 0.750 INCHES FIRST END IN |
| Bolt Hole Nominal Diameter | 0.875 INCHES SECOND END IN |
| Operating Pressure | 350.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Valve Size | 3.000 INCHES IN |
| Adjustable Pressure Range | +156.0 TO 180.0 POUNDS PER SQUARE INCH LBS |
| Bonnet Type | INSIDE SCREW |
| Maximum Operating Temp | 650.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Second Connection Face to Centerline Distance | 6.969 INCHES IN |
| Nominal Outside Diameter | 9.000 INCHES FIRST END IN |
| Nominal Outside Diameter | 8.250 INCHES SECOND END IN |
| Bolt Hole Quantity | 8 ALL ENDS |
| Bonnet Attachment Method | BOLTED |
| First Connection Face to Centerline Distance | 6.094 INCHES IN |
| Material | STEEL BODY |
| Raised Face Nominal Diameter | 6.188 INCHES FIRST END IN |
| Raised Face Nominal Diameter | 5.000 INCHES SECOND END IN |
| Valve Operation Method | AUTOMATIC |
| Raised Face Nominal Height | 0.062 INCHES ALL ENDS IN |
| Nominal Thickness | 1.125 INCHES SECOND END IN |
| Nominal Thickness | 0.938 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 |
|---|---|
| 20040-3X4-156T1 | Anderson Greenwood Lp Dba Anderson Greenwood Crosby (USA) |
| 20040R51SS PRIMARY | Emerson Automation Solutions Final Control Us Lp Div Navy Product Team (USA) |
| Reference | Meaning |
|---|---|
| 20040R51 SSTL 1 | C/1 Advisory reference — outside the item-of-supply concept Anderson Greenwood Lp Dba Anderson Greenwood Crosby |
| UCNCPN15SKKM | 5/9 Secondary reference Danco Valve Company |
| UCNCPN15SKKM | C/1 Advisory reference — outside the item-of-supply concept Dante Valve Company |
| 20040R51SS | 5/9 Secondary reference Anderson Greenwood Lp Dba Anderson Greenwood Crosby |
| DNX62FF-15-3K4 | 5/9 Secondary reference Danco Valve Company |
NSN 4820-01-307-9309 is a Valve,safety Relief, manufactured by Emerson Automation Solutions Final Control Us Lp Div Navy Product Team, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-307-9309 has 2 manufacturer part numbers on file: 20040-3X4-156T1 (Anderson Greenwood Lp Dba Anderson Greenwood Crosby), 20040R51SS (Emerson Automation Solutions Final Control Us Lp Div Navy Product Team).
Key specifications for 20040R51SS: Flow Control Device: DISK; Flange Shape: ROUND WITH HOLES ALL ENDS; Flange Face Design: RAISED STRAIGHT ALL ENDS; Bolt Circle Nominal Diameter: 6.625 INCHES SECOND END IN. 27 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.