A sealing apparatus wherein the nozzle on the forward end portion of a sealing gun on a programmable industrial robot includes a nozzle holder and a nozzle body made of a flexible material. The forward inner end of the nozzle body can gradually diverge and a reinforcement pipe can be provided in the nozzle holder. The nozzle body can be in the form of a tubular brush made of nylon bristles, a solid tubular body of polyurethane foam or a solid tubular body of silicone rubber.
