I am also at a loss to understand your question. What you mean is probably whether gratuity can be paid by the employer periodically on completion of every year of service in the establishment.
First you have to understand that gratuity is not a gratuitous payment made by the employer nor the employee has any rightful claim to gratuity when he is still in service. Still you do so by enticing the employee to accept such periodical payment by means of any bilateral settlement, it would be null and void in view of the overriding effect of the Payment of Gratuity Act,1972 as provided for in its sec.14 for the Act is a complete code in itself on the subject matter of gratuity.. Even if the employee comes forward to accept such periodical payment of gratuity out of ignorance or pecuniary compulsions, it amounts to " contracting out " a concept explicitly or impliedly prohibited under the Labor Laws.
Second, gratuity being a one time lump sum payment on the termination of employment on account of the reasons categorically mentioned in the P.G Act,1972 based on the length of service and last drawn wages is a statutory social security measure of industrial employment.
Therefore, avoid toying with such ideas to circumvent your statutory obligations as an employer.