How post tensioning is done in the precast concrete?

when we are trying to have some precasting pretensioned concrete we have to have two fixed holding jack with at least25 cm free space from the sides we want the pre tension to be,then we have to put the tendons in between two holing jack and fix it from one side,then we have to pull the free side of the tendons and make sure the tension we are expecting has been made in tendons then u can fix the free side too,sure in this method you will need some one side only fixtures the way they cant be opened if the force will effect in different side.then after fixing the tendons you can start concreting and cure the concrete after gainig7 days compressive strength we can easily free teh tendons and cut off the extra length.have a good day