The Valve,safety Relief, cataloged under National Stock Number 4820-01-274-4726, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Hunt Valve Company, Inc.. Government technical data includes 30 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through both NSN and commercial part number lookups. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-274-4726 |
| Primary Part Number | R10AF5J503-CM1 AND D49274 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Hunt Valve Company, Inc. |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Flange Shape | ROUND WITH HOLES ALL ENDS |
| Flange Face Design | RAISED STRAIGHT ALL ENDS |
| Bolt Circle Nominal Diameter | 4.750 INCHES FIRST END IN |
| Bolt Circle Nominal Diameter | 3.125 INCHES SECOND END IN |
| Connection Type | FLANGE ALL ENDS |
| Style Designator | ANGLE FLANGED ENDS |
| Bolt Hole Nominal Diameter | 0.625 INCHES SECOND END IN |
| Bolt Hole Nominal Diameter | 0.750 INCHES FIRST END IN |
| Operating Pressure | 275.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Valve Size | 1.000 INCHES IN |
| Adjustable Pressure Range | +10.0 TO 12.0 POUNDS PER SQUARE INCH LBS |
| Bonnet Type | INSIDE SCREW |
| Maximum Operating Temp | 250.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Second Connection Face to Centerline Distance | 4.500 INCHES IN |
| Nominal Outside Diameter | 4.250 INCHES SECOND END IN |
| Nominal Outside Diameter | 6.000 INCHES FIRST END IN |
| Bolt Hole Quantity | 4 ALL ENDS |
| Bonnet Attachment Method | BOLTED |
| Media for Which Designed | WATER-OIL-GAS SINGLE RESPONSE |
| First Connection Face to Centerline Distance | 4.500 INCHES IN |
| Material | STEEL BODY |
| Material | NICKEL ALLOY FLOW CONTROL DEVICE |
| Material | NICKEL ALLOY SEAT |
| Material | STEEL STEM |
| Raised Face Nominal Diameter | 2.000 INCHES SECOND END IN |
| Raised Face Nominal Diameter | 3.625 INCHES FIRST END IN |
| Valve Operation Method | AUTOMATIC |
| Raised Face Nominal Height | 0.062 INCHES ALL ENDS IN |
| Nominal Thickness | 0.625 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 |
|---|---|
| R10AF5J503-CM1 AND D49274 PRIMARY | Hunt Valve Company, Inc. (USA) |
| Reference | Meaning |
|---|---|
| D49274 ASSY R10AF5J503-CM1 | C/1 Advisory reference — outside the item-of-supply concept Hunt Valve Company, Inc. |
| D49274 ASSY R10AF5J503-CM1 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| R10AF5J503-CM1 | C/1 Advisory reference — outside the item-of-supply concept Hunt Valve Company Inc Dba Union Flonetics |
| R10AF5J503-CM1 AND D49274 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
NSN 4820-01-274-4726 is a Valve,safety Relief, manufactured by Hunt Valve Company, Inc., classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-274-4726 has 1 manufacturer part number on file: R10AF5J503-CM1 AND D49274 (Hunt Valve Company, Inc.).
Key specifications for R10AF5J503-CM1 AND D49274: Flow Control Device: DISK; Flange Shape: ROUND WITH HOLES ALL ENDS; Flange Face Design: RAISED STRAIGHT ALL ENDS; Bolt Circle Nominal Diameter: 4.750 INCHES FIRST END IN. 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.