In Romans 8:18, how is the aorist ἀποκαλυφθῆναι translated as a future tense?

ἀποκαλυφθῆναι Is the aorist and would be translated as “was revealed” Does μέλλουσαν (present tense) “is about to be” somehow change the aorist ἀποκαλυφθῆναι to the future tense? Can someone explain how this aorist is translated as a futur…