A seal plate for repairing damaged areas in a pressure vessel cladding includes a first side and an opposing second side and a sealing portion located on the second side, with the sealing portion circumscribing the seal plate. The seal plate also includes a seal lip extending from a periphery of the sealing portion and a cavity located in the second side, with the cavity circumscribed by the sealing portion. The seal plate further includes at least one purge port extending from the first side to the cavity. Each purge port is in fluid communication with the cavity.
