The Valve,safety Relief, cataloged under National Stock Number 4820-01-540-8335, 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 15 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-540-8335 |
| Primary Part Number | NMP-1531/D-30-C156TO186PSI |
| 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 |
| Flange Shape | ROUND WITH HOLES ALL ENDS |
| Furnished Items and Quantity | 1 LEVER |
| Bolt Circle Nominal Diameter | 2.625 INCHES ALL ENDS IN |
| Connection Type | FLANGE ALL ENDS |
| Style Designator | ANGLE FLANGED ENDS |
| Bolt Hole Nominal Diameter | 0.625 INCHES ALL ENDS IN |
| Adjustable Pressure Range | +156.0 TO 186.0 POUNDS PER SQUARE INCH LBS |
| Nominal Outside Diameter | 4.875 INCHES ALL ENDS IN |
| Disk Loading Method | SPRING |
| Bolt Hole Quantity | 4 ALL ENDS |
| Material | STEEL BODY |
| Material | STEEL CORROSION RESISTING FLOW CONTROL DEVICE |
| Material | STEEL CORROSION RESISTING STEM |
| Valve Operation Method | AUTOMATIC OR MANUAL |
| Nominal Thickness | 0.625 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 |
|---|---|
| D-30-C/156TO186PSI | Emerson Automation Solutions Final Control Us Lp Div Navy Product Team (USA) |
| NMP-1531/D-30-C156TO186PSI PRIMARY | Emerson Automation Solutions Final Control Us Lp Div Navy Product Team (USA) |
| Reference | Meaning |
|---|---|
| D-30-C/156TO186PSI | 5/9 Secondary reference Keystone Intl Inc |
| NMP-1531/D-30-C156TO186PSI | 5/9 Secondary reference Keystone Intl Inc |
NSN 4820-01-540-8335 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 4820-01-540-8335 has 2 manufacturer part numbers on file: D-30-C/156TO186PSI (Emerson Automation Solutions Final Control Us Lp Div Navy Product Team), NMP-1531/D-30-C156TO186PSI (Emerson Automation Solutions Final Control Us Lp Div Navy Product Team).
Key specifications for NMP-1531/D-30-C156TO186PSI: Flange Shape: ROUND WITH HOLES ALL ENDS; Furnished Items and Quantity: 1 LEVER; Bolt Circle Nominal Diameter: 2.625 INCHES ALL ENDS IN; Connection Type: FLANGE ALL ENDS. 15 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.