The Valve,safety Relief, cataloged under National Stock Number 4820-01-258-2698, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 29 specifications, cited from the U.S. Government catalog. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-258-2698 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Flange Shape | ROUND WITH HOLES ALL ENDS |
| Furnished Items and Quantity | 1 LEVER |
| Flange Face Design | PLAIN ALL ENDS |
| Bolt Circle Nominal Diameter | 5.000 INCHES ALL ENDS IN |
| Connection Type | FLANGE ALL ENDS |
| Style Designator | ANGLE FLANGED ENDS |
| Material Document and Classification | ASTM B61 ASSN STD SINGLE MATERIAL RESPONSE BODY |
| Material Document and Classification | QQ-N-281 FED SPEC SINGLE MATERIAL RESPONSE FLOW CONTROL DEVICE |
| Material Document and Classification | QQ-N-281 FED SPEC SINGLE MATERIAL RESPONSE SEAT |
| Material Document and Classification | QQ-N-271 FED SPEC SINGLE MATERIAL RESPONSE STEM |
| Bolt Hole Nominal Diameter | 0.687 INCHES ALL ENDS IN |
| Valve Size | 2.500 INCHES IN |
| Bonnet Type | INSIDE SCREW |
| Maximum Operating Temp | 425.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Second Connection Face to Centerline Distance | 5.500 INCHES IN |
| Nominal Outside Diameter | 6.125 INCHES ALL ENDS IN |
| Disk Loading Method | WEIGHT |
| Bolt Hole Quantity | 6 ALL ENDS |
| Bonnet Attachment Method | BOLTED |
| Media for Which Designed | WATER-OIL-GAS SINGLE RESPONSE |
| First Connection Face to Centerline Distance | 5.500 INCHES IN |
| Material | COPPER ALLOY BODY |
| Material | NICKEL ALLOY STEM |
| Material | NICKEL ALLOY FLOW CONTROL DEVICE |
| Material | NICKEL ALLOY SEAT |
| Opening Pressure Setting | 140.0 POUNDS PER SQUARE INCH LBS |
| Valve Operation Method | AUTOMATIC |
| Nominal Thickness | 0.937 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 |
| Reference | Meaning |
|---|---|
| D50559 AND R10AK3K3AE-BM3 | 3/9 Design control — primary reference Hunt Valve Company Inc Dba Union Flonetics |
| D50559 AND R10AK3K3AE-BM3 | C/1 Advisory reference — outside the item-of-supply concept Hunt Valve Company, Inc. |
| D50559 | D/9 Drawing number reference only Hunt Valve Company Inc Dba Union Flonetics |
| R10AK3K3AE-BM3 | C/1 Advisory reference — outside the item-of-supply concept Hunt Valve Company Inc Dba Union Flonetics |
NSN 4820-01-258-2698 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
2 possible matches (shared part number, not a government interchangeability claim): 4820-01-258-2767, 4820-01-382-6510. Verify interchangeability with system specifications before substitution.
Key specifications for 4820-01-258-2698: Flow Control Device: DISK; Flange Shape: ROUND WITH HOLES ALL ENDS; Furnished Items and Quantity: 1 LEVER; Flange Face Design: PLAIN ALL ENDS. 29 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.