Seal pin flow rate method and system

1. A method for simultaneously forming and filling a container from a preform with fluid while a finish of the container is connected to a nozzle of a forming and filling system, the method comprising:

determining an effective fill area at an opening of the finish through which the fluid can pass while a stretch rod of the forming and filling system is seated within the opening;

actuating a seal pin of the forming and filling system to open a nozzle passage of the nozzle to allow the fluid to flow through the nozzle passage and through the opening of the finish to simultaneously form the container from the preform and fill the container;

detecting a degree to which the nozzle passage is open;

increasing fill velocity of the fluid to the nozzle as the nozzle passage is opened;

setting fill velocity of the fluid to a maximum fill velocity when the nozzle passage is opened such that an area of the nozzle passage is at least equal to the effective fill area at the opening of the finish;

setting the fill velocity of the fluid to the maximum fill velocity after the seal pin has been actuated to make the area of the nozzle passage equal to the effective fill area at the opening of the finish; and

closing the seal pin to close the nozzle passage after the container is formed and filled.

2. The method of claim 1 , wherein determining the effective fill area at the opening of the finish includes:

determining a difference between an inside diameter of the finish and an outside diameter of the stretch rod, the difference equal to the effective fill area.

3. The method of claim 1 , wherein the degree to which the nozzle passage is open is detected by determining how far the seal pin has moved from a closed position to an open position.

4. The method of claim 3 , further comprising determining a distance that the seal pin has moved from the closed position to the open position when in the open position an area of the nozzle passage is equal to the effective fill area.

5. The method of claim 4 , further comprising measuring the distance that the seal pin has moved with a laser sensor or a linear variable differential transducer.

6. The method of claim 1 , further comprising initiating fluid flow to the nozzle before opening the nozzle passage.

7. The method of claim 1 , further comprising further actuating the seal pin to make the area of the nozzle passage greater than the effective fill area at the opening of the finish after setting the fill velocity of the fluid to the maximum fill velocity.

8. The method of claim 1 , further comprising maintaining the seal pin in an open position such that the area of the nozzle passage is at least equal to the effective fill area at the opening of the finish after the fill velocity of the fluid has been reduced from the maximum fill velocity.

9. The method of claim 1 , further comprising closing the seal pin to close the nozzle passage after reducing the fill velocity to zero.

10. A method for simultaneously forming and filling a container from a preform with fluid while a finish of the container is connected to a nozzle of a forming and filling system, the method comprising:

determining an effective fill area at an opening of the finish through which the fluid can pass while a stretch rod of the forming and filling system is seated within the opening;

actuating a seal pin of the forming and filling system to open a nozzle passage of the nozzle to allow the fluid to flow through the nozzle passage and through the opening of the finish to simultaneously form the container from the preform and fill the container;

detecting a degree to which the nozzle passage is open;

increasing fill velocity of the fluid to the nozzle as the nozzle passage is opened;

setting fill velocity of the fluid to a maximum fill velocity when the nozzle passage is opened such that an area of the nozzle passage is at least equal to the effective fill area at the opening of the finish; and

closing the seal pin to close the nozzle passage after the container is formed and filled;

wherein the degree to which the nozzle passage is open is detected by determining how far the seal pin has moved from a closed position to an open position; and

wherein the method further includes determining a distance that the seal pin has moved from the closed position to the open position when in the open position an area of the nozzle passage is equal to the effective fill area.

11. The method of claim 10 , wherein the method further includes measuring the distance that the seal pin has moved with a laser sensor or a linear variable differential transducer.