Charles Ellicott Commentary 2 Chronicles 4:2

"Also he made the molten sea of ten cubits from brim to brim, round in compass; and the height thereof was five cubits; and a line of thirty cubits compassed it round about." — 2 Chronicles 4:2 (ASV)

Even if pôthôth is correct in Kings, the chronicler might have understood the word to mean openings, rather than hinges, and so substituted the common word pethah, which has that sense. The resemblance of the one word to the other would be a further consideration in its favour, according to ancient notions of interpretation.