The Valve,safety Relief, cataloged under National Stock Number 4820-01-350-3686, is classified within Federal Supply Class 4820 (No Item Name Available) of the Valves group. The primary manufacturer of record is Circor Aerospace, Inc. Dba Circor Aerospace Inc. Government technical data includes 16 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 4 commercial cross-references from 3 manufacturers, enabling identification through both NSN and commercial part number lookups. 1 verified substitute exists in the FLIS interchangeability database. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-350-3686 |
| Primary Part Number | 577A1-4D-30 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — No Item Name Available |
| Manufacturer | Circor Aerospace, Inc. Dba Circor Aerospace Inc |
| Status | ACTIVE |
| Nominal Thread Size | 0.438 INCHES ALL ENDS IN |
| Valve Discharge Flow Rate | 0.7 GALLONS PER MINUTE |
| Thread Quantity Per Inch | 20 ALL ENDS |
| Disk Loading Method | SPRING |
| Valve Operation Method | AUTOMATIC |
| Flow Control Device | DISK |
| Thread Class | 3A ALL ENDS A |
| Opening Pressure Setting | 30.0 POUNDS PER SQUARE INCH LBS |
| Surface Treatment | ANODIZE LOCATION NOT OTHERWISE SPECIFIED |
| Thread Series Designator | UNIFIED NATIONAL JOINT (UNJ) ALL ENDS |
| Connection Style | EXTERNAL SEAT FOR GASKET SEAL (BOSS) ALL ENDS |
| Maximum Operating Temp | 180.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Connection Type | THREADED EXTERNAL BOSS ALL ENDS |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Material | ALUMINUM ALLOY BODY |
| Style Designator | STRAIGHT THRU |
| Acquisition Status | ACTIVE |
| HAZMAT | No |
| Part Number | Manufacturer |
|---|---|
| 334220 | Howden Fluid Systems (USA) |
| 577A1-4D-30 PRIMARY | Circor Aerospace, Inc. Dba Circor Aerospace Inc (USA) |
| 334220P01 | Meggitt (north Hollywood), Inc. Dba Meggitt Control Systems Div Meggitt Defense Systems, Inc. (USA) |
| 334220P01 | Howden Fluid Systems (USA) |
NSN 4820-01-350-3686 is a Valve,safety Relief, manufactured by Circor Aerospace, Inc. Dba Circor Aerospace Inc, classified under FSC 4820 (No Item Name Available). Status: active.
NSN 4820-01-350-3686 has 4 cross-referenced part numbers: 334220 (Howden Fluid Systems), 577A1-4D-30 (Circor Aerospace, Inc. Dba Circor Aerospace Inc), 334220P01 (Meggitt (north Hollywood), Inc. Dba Meggitt Control Systems Div Meggitt Defense Systems, Inc.), 334220P01 (Howden Fluid Systems).
There is 1 known substitute for 4820-01-350-3686: 5940-00-549-7256. Verify interchangeability with system specifications before substitution.
Key specifications for 577A1-4D-30: Nominal Thread Size: 0.438 INCHES ALL ENDS IN; Valve Discharge Flow Rate: 0.7 GALLONS PER MINUTE; Thread Quantity Per Inch: 20 ALL ENDS; Disk Loading Method: SPRING. 16 total characteristics are documented in the Federal Logistics Information System.