Both styles are interchangeable on the modern flat bottom groove, however only the oval style can be used in the old type round bottom groove.
Style R ring type joints are designed to seal pressure up to 6,250 psi in accordance with ASME B16.5 pressure ratings and up to 5,000 psi in accordance with API 6A pressure ratings.
Flange Face: RTJ
Maximum Temperature: 0°C / 32°F
Minimum Temperature: 0°C / -32°F
Pressure: 431 Bars / 6251.14 PSI
Pressure Class: 150, 300, 600, 1500, 2500, 400, 900, Up to API 5