You have not indicated whether the "ship repair" is being done at a "major port" as declared by the Government of India. By virtue of provisions contained under Section 2(a)(i) of the Industrial Disputes Act, 1947, the Central Government is the "appropriate government" in respect of all major ports. If such a factory is located in a major port, in my opinion, the Regional Central Labor Commissioner will have jurisdiction.
Otherwise, in all other cases, the State Labor Commissioner will have jurisdiction. Please see the definition of "appropriate government" as laid down in the above Act.