The Valve,check, cataloged under National Stock Number 4820-00-822-4644, is classified within Federal Supply Class 4820 (No Item Name Available) of the Valves group. The primary manufacturer of record is The Walworth Company. Government technical data includes 16 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 3 commercial cross-references from 2 manufacturers, enabling identification through both NSN and commercial part number lookups. 8 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Cancelled.
| Parameter | Value |
|---|---|
| NSN | 4820-00-822-4644 |
| Primary Part Number | 4201-4 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — No Item Name Available |
| Manufacturer | The Walworth Company |
| Status | CANCELLED |
| Mounting Position | HORIZONTAL |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Connection Type | THREADED INTERNAL PIPE ALL ENDS |
| Maximum Operating Temp | 500.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Operating Pressure | 400.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SECOND RESPONSE LBS |
| Nominal Thread Size | 0.250 INCHES ALL ENDS IN |
| Media for Which Designed | WATER-OIL-GAS SECOND RESPONSE |
| Media for Which Designed | STEAM FIRST RESPONSE |
| Style Designator | STRAIGHT THRU |
| Connection Style | GROOVED INSIDE ALL ENDS |
| Operating Pressure | 200.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM FIRST RESPONSE LBS |
| Valve Operation Method | AUTOMATIC |
| Flow Control Device | DISK |
| Thread Series Designator | NPT ALL ENDS |
| Material | COPPER ALLOY OVERALL |
| Nondefinitive Spec/std Data | 3 TYPE AND 200/WSP/ CLASS AND 1/4 SIZE |
| Acquisition Status | CANCELLED |
| HAZMAT | No |
| Part Number | Manufacturer |
|---|---|
| 4201-4 | The Walworth Company (USA) |
| MILV18436 | Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M |
| MIL-DTL-18436 | Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M |
NSN 4820-00-822-4644 is a Valve,check, manufactured by The Walworth Company, classified under FSC 4820 (No Item Name Available). Status: cancelled.
NSN 4820-00-822-4644 has 3 cross-referenced part numbers: 4201-4 (The Walworth Company), MILV18436 (Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M), MIL-DTL-18436 (Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M).
There are 8 known substitutes for 4820-00-822-4644: 5999-00-383-2215, 5999-00-671-9447, 6150-00-752-5060 and 5 more. Verify interchangeability with system specifications before substitution.
Key specifications for 4201-4: Mounting Position: HORIZONTAL; Thread Direction: RIGHT-HAND ALL ENDS; Connection Type: THREADED INTERNAL PIPE ALL ENDS; Maximum Operating Temp: 500.0 FAHRENHEIT SINGLE RESPONSE DEGF. 16 total characteristics are documented in the Federal Logistics Information System.
NSN 4820-00-822-4644 is currently cancelled. Check with the Defense Logistics Agency for current availability and authorized substitutes.