Overtime Regulations Under the Factories Act
The Factories Act provides for maximum overtime hours per week and per quarter. The maximum hours an employee shall be asked to work should not exceed 10 hours. The spread over, including the intervals of rest, should not exceed 12 hours a day. The working hours, inclusive of overtime, should not exceed 60 hours in a week. Additionally, the total overtime hours should not exceed 50 in a quarter. This has been extended to 75 hours a quarter by state amendments, I believe. However, a single day shift of 14 hours is not lawful, even if you pay wages at double the rate.
As already pointed out, if this is a one-time arrangement, you can do it, but you should not make it a regular practice. To meet your market demands, you will have to engage additional labor.