Schematic — drawn from the table, not to scale for inspection.
| Symbol | Item | Value |
|---|---|---|
| D | Outside diameter | 345mm |
| C | Flange thickness / blind thickness | 20mm |
| D2 | Raised face diameter | 277mm |
| f | Raised face height | 2mm |
| K | Bolt circle diameter | 305mm |
| n | Number of bolt holes | 12pcs |
| d | Bolt hole diameter | 23mm |
| A | Hub diameter | 261mm |
| H | Hub length / overall length | 54mm |
| B | Welding-end diameter | 241.8mm |
Source: Table 11 (pp. 15–16) — pressure-temperature rating, maximum working pressure in MPa; Group 1.1.
Base material: SS400 / S25C (Japan, Korea, South-East Asia, marine and shipbuilding)
Rating: JIS K ratings are kgf/cm² nominal: 5K ≈ 0.5 MPa, 10K ≈ 1.0 MPa, 16K ≈ 1.6 MPa, 20K ≈ 2.0 MPa and 30K ≈ 3.0 MPa. The published maximum working pressure is higher or lower than the nominal figure depending on material group and division — for material…
Tolerances / marking: Tolerances, material groups and marking: JIS B2220:2012, including Table 11.