The Union,tube, cataloged under National Stock Number 4730-01-137-0903, is classified within Federal Supply Class 4730 (Hose, Pipe, Tube, Lubrication, and Railing Fittings) of the Pipe, Tubing, Hose, and Fittings group. Government technical data includes 17 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4730-01-137-0903 |
| Item Name | Union,tube |
| FSC / FSG | 4730 / 47 — Hose, Pipe, Tube, Lubrication, and Railing Fittings |
| Status | ACTIVE |
| Furnished Items and Quantity | 1 PREFORMED PACKING |
| Connection Style | SOCKET (TUBE) ALL ENDS |
| Coupling Flange Shape | ROUND |
| Tubing Wall Nominal Thickness for Which Designed | 0.140 INCHES ALL ENDS IN |
| Nominal Overall Length | 2.250 INCHES IN |
| Connection Type | UNTHREADED INTERNAL TUBE ALL ENDS |
| Style Designator | FLANGED |
| Material Document and Classification | QQ-S-763,COND A FED SPEC SINGLE MATERIAL RESPONSE TAILPIECE |
| Material Document and Classification | QQ-N-281 FED SPEC SINGLE MATERIAL RESPONSE NUT |
| Material Document and Classification | QQ-S-763,COND A FED SPEC SINGLE MATERIAL RESPONSE THREAD PIECE |
| Nominal Outside Diameter Tube Accommodated | 0.250 INCHES ALL ENDS IN |
| Operating Pressure | 5100.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Seat Type | GASKET |
| Material | NICKEL ALLOY NUT |
| Material | STEEL COMP 304 THREAD PIECE |
| Material | STEEL COMP 304 TAILPIECE |
| Reducer Type | CONCENTRIC |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| 2621-791-03ASSY80 | 3/2 Design control — primary reference U.S. Government activity |
| 2621-791-03 | D/9 Drawing number reference only U.S. Government activity |
NSN 4730-01-137-0903 is a Union,tube, classified under FSC 4730, Hose, Pipe, Tube, Lubrication, and Railing Fittings. Status: active.
Key specifications for 4730-01-137-0903: Furnished Items and Quantity: 1 PREFORMED PACKING; Connection Style: SOCKET (TUBE) ALL ENDS; Coupling Flange Shape: ROUND; Tubing Wall Nominal Thickness for Which Designed: 0.140 INCHES ALL ENDS 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.