The Flange,pipe, cataloged under National Stock Number 4730-01-311-1000, is classified within Federal Supply Class 4730 (Hose, Pipe, Tube, Lubrication, and Railing Fittings) of the Pipe, Tubing, Hose, and Fittings group. The manufacturer of record is Ati Ladish Llc Dba Ati Wah Chang Div Ati Forged Products - Cudahy. Government technical data includes 17 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4730-01-311-1000 |
| Primary Part Number | 20-1/2 ASTMA105 |
| Item Name | Flange,pipe |
| FSC / FSG | 4730 / 47 — Hose, Pipe, Tube, Lubrication, and Railing Fittings |
| Manufacturer | Ati Ladish Llc Dba Ati Wah Chang Div Ati Forged Products - Cudahy |
| Status | ACTIVE |
| Socket Diameter | 0.880 INCHES NOMINAL IN |
| Flange Diameter | 3.500 INCHES NOMINAL IN |
| Face Seating Surface Condition | MACHINED |
| Nominal Pipe Size for Which Designed | 0.500 INCHES IN |
| Socket Depth | 0.375 INCHES NOMINAL IN |
| Flange Section Style | RAISED FACE, SOCKET NECK |
| Style Designator | ROUND, ONE BOLT HOLE CIRCLE |
| Bolt Hole Diameter | 0.500 INCHES NOMINAL IN |
| Neck Height | 0.188 INCHES NOMINAL IN |
| Material Document and Classification | ASTM A105 ASSN STD SINGLE MATERIAL RESPONSE |
| Specification/standard Data | 80204-B16.5 PROFESSIONAL/INDUSTRIAL ASSOCIATION STANDARD |
| Bolt Hole Quantity | 4 |
| Bolt Circle Diameter | 2.375 INCHES NOMINAL IN |
| Raised Face Diameter | 1.375 INCHES NOMINAL IN |
| Raised Face Height | 0.062 INCHES NOMINAL IN |
| Material | STEEL |
| Thickness | 0.437 INCHES NOMINAL 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 |
|---|---|
| 20-1/2 ASTMA105 PRIMARY | Ati Ladish Llc Dba Ati Wah Chang Div Ati Forged Products - Cudahy (USA) |
| Reference | Meaning |
|---|---|
| B16.5 | 5/1 Secondary reference U.S. Government activity |
NSN 4730-01-311-1000 is a Flange,pipe, manufactured by Ati Ladish Llc Dba Ati Wah Chang Div Ati Forged Products - Cudahy, classified under FSC 4730, Hose, Pipe, Tube, Lubrication, and Railing Fittings. Status: active.
NSN 4730-01-311-1000 has 1 manufacturer part number on file: 20-1/2 ASTMA105 (Ati Ladish Llc Dba Ati Wah Chang Div Ati Forged Products - Cudahy).
Key specifications for 20-1/2 ASTMA105: Socket Diameter: 0.880 INCHES NOMINAL IN; Flange Diameter: 3.500 INCHES NOMINAL IN; Face Seating Surface Condition: MACHINED; Nominal Pipe Size for Which Designed: 0.500 INCHES IN. 17 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.