The Valve,safety Relief, cataloged under National Stock Number 4820-01-499-9884, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Ausco Inc. Government technical data includes 13 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-499-9884 |
| Primary Part Number | A640 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Ausco Inc |
| Status | ACTIVE |
| Surface Treatment Document and Classification | QQ-P-35,TYPE11 FED SPEC SINGLE TREATMENT RESPONSE LOCATION NOT OTHERWISE SPECIFIED |
| Connection Style | PLAIN (PIPE) FIRST END |
| Connection Type | THREADED EXTERNAL PIPE FIRST END |
| Style Designator | STRAIGHT THRU NOTE: TO BE USED FOR VALVE BODIES OF SEPARABLE SECTIONS. |
| Material Document and Classification | QQ-S-763 FED SPEC SINGLE MATERIAL RESPONSE OR ASTM-A-479 ASSN STD SINGLE MATERIAL RESPONSE BODY |
| Thread Direction | RIGHT-HAND FIRST END |
| Seat Angle | 37.0 DEGREES ALL ENDS |
| Seat Angle | 37.0 DEGREES FIRST END |
| Maximum Operating Temp | 75.0 CELSIUS SINGLE RESPONSE DEGC |
| Surface Treatment | PASSIVATE LOCATION NOT OTHERWISE SPECIFIED |
| Material | STEEL COMP 316 BODY |
| Opening Pressure Setting | 175.0 POUNDS PER SQUARE INCH LBS |
| Valve Operation Method | AUTOMATIC |
| 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 |
|---|---|
| A640 PRIMARY | Ausco Inc (USA) |
| Reference | Meaning |
|---|---|
| RV05-350 | 3/2 Design control — primary reference U.S. Government activity |
| 1452611-1 | 7/2 Vendor item drawing reference U.S. Government activity |
| 1452611 | D/9 Drawing number reference only U.S. Government activity |
NSN 4820-01-499-9884 is a Valve,safety Relief, manufactured by Ausco Inc, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-499-9884 has 1 manufacturer part number on file: A640 (Ausco Inc).
Key specifications for A640: Surface Treatment Document and Classification: QQ-P-35,TYPE11 FED SPEC SINGLE TREATMENT RESPONSE LOCATION NOT OTHERWISE SPECIFIED; Connection Style: PLAIN (PIPE) FIRST END; Connection Type: THREADED EXTERNAL PIPE FIRST END; Style Designator: STRAIGHT THRU NOTE: TO BE USED FOR VALVE BODIES OF SEPARABLE SECTIONS.. 13 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.