The Insert,flexible Coupling, cataloged under National Stock Number 3010-00-528-0812, is classified within Federal Supply Class 3010 (Torque Converters and Speed Changers) of the Mechanical Power Transmission Equipment group. The manufacturer of record is Charles Bond Company Dba Christiana Machine Company. Government technical data includes 4 specifications, cited from the U.S. Government catalog. The record lists 7 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 17 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 3010-00-528-0812 |
| Primary Part Number | B321-2 |
| Item Name | Insert,flexible Coupling |
| FSC / FSG | 3010 / 30 — Torque Converters and Speed Changers |
| Manufacturer | Charles Bond Company Dba Christiana Machine Company |
| Status | ACTIVE |
| Overall Thickness | 0.500 INCHES NOMINAL IN |
| Style Designator | SPIDER |
| Lug Quantity | 6 |
| Material | RUBBER |
| 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 |
|---|---|
| SG2178PC13C | Circor Pumps North America Llc (USA) |
| B321-2 PRIMARY | Charles Bond Company Dba Christiana Machine Company (USA) |
| B321-2 | Siemens Energy, Inc. (USA) |
| SSK1S5501-3106638 | Naval Sea Systems Command (USA) |
| S5502H3123453PC86PC88 | Naval Sea Systems Command (USA) |
| HS4503-3102155PCBPC13C | Naval Sea Systems Command (USA) |
| S4700H3108204REV19PC88 | Naval Sea Systems Command (USA) |
| Reference | Meaning |
|---|---|
| 3N193PC88 | 5/9 Secondary reference Alfa Laval Inc. |
| 8AB4 | 5/9 Secondary reference Alfa Laval Inc. |
| S4700H3108204REV19PC88 | 5/9 Secondary reference U.S. Government activity |
| SG2178PC13C | 5/9 Secondary reference Siemens Energy, Inc. |
| 8AB4 | C/1 Advisory reference — outside the item-of-supply concept Charles Bond Company Dba Christiana Machine Company |
| C17-4-1 | 5/9 Secondary reference Todd Shipyards Corp Brooklyn Div |
| 3N144PC88 | 5/9 Secondary reference Alfa Laval Inc. |
| HS4503-3102155PCBPC13C | 5/9 Secondary reference U.S. Government activity |
| 3N141PC88 | 5/9 Secondary reference Alfa Laval Inc. |
| 3N135PC88 | 5/9 Secondary reference Alfa Laval Inc. |
| NN115PC88 | 5/9 Secondary reference Alfa Laval Inc. |
| SG2483-13C | 5/9 Secondary reference Siemens Energy, Inc. |
| SSK1S5501-3106638 | 5/9 Secondary reference U.S. Government activity |
| 3N177PC88 | 5/9 Secondary reference Alfa Laval Inc. |
| S5502H3123453PC86PC88 | 5/9 Secondary reference U.S. Government activity |
| 3N170PC88 | 5/9 Secondary reference Alfa Laval Inc. |
| 8ABY | 5/9 Secondary reference Alfa Laval Inc. |
NSN 3010-00-528-0812 is a Insert,flexible Coupling, manufactured by Charles Bond Company Dba Christiana Machine Company, classified under FSC 3010, Torque Converters and Speed Changers. Status: active.
NSN 3010-00-528-0812 has 7 manufacturer part numbers on file: SG2178PC13C (Circor Pumps North America Llc), B321-2 (Charles Bond Company Dba Christiana Machine Company), B321-2 (Siemens Energy, Inc.), SSK1S5501-3106638 (Naval Sea Systems Command), S5502H3123453PC86PC88 (Naval Sea Systems Command) and 2 more.
2 possible matches (shared part number, not a government interchangeability claim): 5930-01-197-2205, 2510-01-728-6322. Verify interchangeability with system specifications before substitution.
Key specifications for B321-2: Overall Thickness: 0.500 INCHES NOMINAL IN; Style Designator: SPIDER; Lug Quantity: 6; Special Features: LAMINATED CONSTRUCTION FEATURE-NOT INCL.;WDTH ACROSS FLATS 2.125 IN. IN. 4 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.