Source: As worded by Indian Railways, Government of India

If the ticket that was torn/mutilated was a Confirmed one or RAC, a duplicate ticket will be issued on collection of 25% of the fare, after the preparation of Reservation Chart.

Before chart preparation, charges are same as applicable for issue of duplicate ticket in lieu of the lost/misplaced ticket. No duplicate ticket will be issued in case of mutilated Waitlisted tickets. Besides, refund is admissible on torn/mutilated ticket if its genuineness and authenticity are verified on the basis of particulars visible on the face of such a ticket.