| 1/00 | Underframes (making railway vehicle underframes by forging or pressing B21K 7/12) |
| 1/02 | Underframes (making railway vehicle underframes by forging or pressing B21K 7/12) with a single central sill |
| 1/04 | Underframes (making railway vehicle underframes by forging or pressing B21K 7/12) of triangulated type |
| 1/06 | Underframes (making railway vehicle underframes by forging or pressing B21K 7/12) specially adapted for locomotives or motor-driven railcars |
| 1/08 | Underframes (making railway vehicle underframes by forging or pressing B21K 7/12) Details |
| 1/10 | Underframes (making railway vehicle underframes by forging or pressing B21K 7/12) Details End constructions |
| 1/12 | Underframes (making railway vehicle underframes by forging or pressing B21K 7/12) Details Cross bearers |
| 1/14 | Underframes (making railway vehicle underframes by forging or pressing B21K 7/12) Details Attaching or supporting vehicle body structure |
| 3/00 | Types of bogies (B61F 5/00 takes precedence) |
| 3/02 | Types of bogies (B61F 5/00 takes precedence) with more than one axle |
| 3/04 | Types of bogies (B61F 5/00 takes precedence) with more than one axle with driven axles or wheels |
| 3/06 | Types of bogies (B61F 5/00 takes precedence) with more than one axle with driven axles or wheels with three or more axles |
| 3/08 | Types of bogies (B61F 5/00 takes precedence) with more than one axle without driven axles or wheels |
| 3/10 | Types of bogies (B61F 5/00 takes precedence) with more than one axle without driven axles or wheels with three or more axles |
| 3/12 | Types of bogies (B61F 5/00 takes precedence) specially modified for carrying adjacent vehicle bodies of articulated trains |
| 3/14 | Types of bogies (B61F 5/00 takes precedence) specially modified for reducing air resistance |
| 3/16 | Types of bogies (B61F 5/00 takes precedence) with a separate axle for each wheel |
| 5/00 | Constructional details of bogies; Connections between bogies and vehicle underframes; Arrangements or devices for adjusting or allowing self-adjustment of wheel axles or bogies when rounding curves |
| 5/02 | Constructional details of bogies; Connections between bogies and vehicle underframes; Arrangements or devices for adjusting or allowing self-adjustment of wheel axles or bogies when rounding curves Arrangements permitting limited transverse relative movements between vehicle underframe or bolster and bogie; Connections between underframes and bogies |
| 5/04 | Constructional details of bogies; Connections between bogies and vehicle underframes; Arrangements or devices for adjusting or allowing self-adjustment of wheel axles or bogies when rounding curves Arrangements permitting limited transverse relative movements between vehicle underframe or bolster and bogie; Connections between underframes and bogies Bolster supports or mountings (side bearings B61F 5/14) |