BX type pad ring is designed for the highest up to 2000opsi. The pad ring is used with the APl-6BX flange and AP1-168X. 

The section of the BX type pad ring is slightly higher than the diameter of the flange.When the flange is bolted to therespective torque value, forcing the first sealing pad ring in the outer corner and then the two timeSealed inside.All of the BX type cushion rings contain a pressure vent to ensure that the pressure in the pad ring groove is maintained. 

RX type pad ring is designed for the highest up to about 10000psi. The pad ring is designed and assembled in the same ring groove as the standard R pad ring. The pad ring can be used withR- type API - and star- star ring swap on the flange of 6B. RX type cushion ring is very useful for the API6B flange type blowout prevention unit. It is needed to add a large amount of it.The RX type pad ring is subjected to a higher Pressure with its stronger vibration and heavier weight.