The Valve,safety Relief, cataloged under National Stock Number 4820-01-170-7047, 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 26 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-170-7047 |
| Primary Part Number | R10AF2F208-BM1 D49254 |
| 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 | PLAIN ALL ENDS |
| Bolt Circle Nominal Diameter | 3.120 INCHES ALL ENDS IN |
| Connection Type | FLANGE ALL ENDS |
| Style Designator | ANGLE FLANGED ENDS |
| Material Document and Classification | QQ-N-281 FED SPEC SINGLE MATERIAL RESPONSE FLOW CONTROL DEVICE |
| Material Document and Classification | ASTM B-61 ASSN STD SINGLE MATERIAL RESPONSE BODY |
| Material Document and Classification | ASTM A276 ASSN STD SINGLE MATERIAL RESPONSE STEM |
| Bolt Hole Nominal Diameter | 0.562 INCHES ALL ENDS IN |
| Operating Pressure | 400.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Valve Size | 1.000 INCHES IN |
| Adjustable Pressure Range | +27.0 TO 33.0 POUNDS PER SQUARE INCH LBS |
| Bonnet Type | OUTSIDE SCREW-YOKE |
| Maximum Operating Temp | 250.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Second Connection Face to Centerline Distance | 3.625 INCHES IN |
| Nominal Outside Diameter | 4.250 INCHES ALL ENDS IN |
| Bolt Hole Quantity | 4 ALL ENDS |
| Bonnet Attachment Method | THREADED |
| First Connection Face to Centerline Distance | 3.625 INCHES IN |
| Material | COPPER ALLOY BODY |
| Material | STEEL COMP 303 STEM |
| Material | NICKEL ALLOY FLOW CONTROL DEVICE |
| Material | NICKEL ALLOY SEAT |
| Valve Operation Method | AUTOMATIC |
| Nominal Thickness | 0.562 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 |
|---|---|
| R10AF2F208-BM1 D49254 PRIMARY | Hunt Valve Company, Inc. (USA) |
| Reference | Meaning |
|---|---|
| R10AF2F208 27T33PSI D49915 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| D49915 | D/9 Drawing number reference only Hunt Valve Company Inc Dba Union Flonetics |
| R10AF2F208-BM1 D49254 | 3/9 Design control — primary reference Hunt Valve Company Inc Dba Union Flonetics |
NSN 4820-01-170-7047 is a Valve,safety Relief, manufactured by Hunt Valve Company, Inc., classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-170-7047 has 1 manufacturer part number on file: R10AF2F208-BM1 D49254 (Hunt Valve Company, Inc.).
1 possible match (shared part number, not a government interchangeability claim): 4820-01-170-9141. Verify interchangeability with system specifications before substitution.
Key specifications for R10AF2F208-BM1 D49254: Flow Control Device: DISK; Flange Shape: ROUND WITH HOLES ALL ENDS; Flange Face Design: PLAIN ALL ENDS; Bolt Circle Nominal Diameter: 3.120 INCHES ALL ENDS IN. 26 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.