Directors at Orange National Bank have promoted Kenneth J. Cosgrove, 38, to the newly created position of executive vice president and senior credit officer. Frank A. (Tony) Del Giorgio, 41, has been named to Cosgrove’s former position as senior vice president for loan administration. Cosgrove of Laguna Hills is a founding vice president of the 7-year-old bank. Del Giorgio of Fullerton was hired as a vice president in 1984.