No — PN 16 (EN 1092-1) and 16K (JIS B2220) are similar but not identical. PN 16 is rated 16 bar at room temperature; 16K is rated 16 kgf/cm² (≈ 15.7 bar). For low-pressure water / utility, the difference is usually negligible. For higher classes (PN 40 / 20K, PN 100 / 30K), the bolt patterns and dimensions diverge and direct substitution is not allowed.

Sometimes — at small sizes (DN 50-100 / 50A-100A) and low pressure (PN 16 / 10K), the bolt-circle diameter and bolt count match. Above DN 150 / 150A, bolt size, count, or BC typically diverge, and substitution is not safe. Always check the contractual specification; do not rely on nominal size alone.

EN Form B1 (Raised Face, 2 mm) is equivalent to JIS "RF" (Raised Face, 2 mm). Both standards use 2 mm RF height as the most common raised-face configuration for general service. EN Form B2 (1 mm RF) is an EN-only variant — JIS does not specify a 1 mm RF.

No — JIS B2220 does not define a standard Ring Type Joint (RTJ) groove. For RTJ applications in Japanese projects, the specification typically references ASME B16.5 RTJ (Type R oval or Type RX/BX octagonal). If you need JIS-stamped flanges with RTJ grooves, it is a custom order — confirm with the manufacturer.

JIS B2220 does not have a direct equivalent to ASTM A105. The closest JIS carbon steel forgings are SF390A / SF440A (JIS G3201). For pressure-bound service with A105 chemistry, JIS forgings must be verified against the project specification. We typically supply EN 1092-1 flanges in P250GH / P280GH (which are closer to A105 than JIS grades).

Mixed-standard projects typically have European process design (EN 1092-1) with Japanese-sourced equipment or Japanese contractors (JIS B2220). For example, a Japanese EPC working on a European client's plant. In these cases, the boundary between EN and JIS is locked at the design stage — usually process-side EN, utility-side JIS. Adapters or transition flanges may be required at the boundary.