Abstract: A method for producing sealed packages filled with fluid material wherein a limited amount of the material is delivered into a predetermined length of flexible, thermoplastic tubing, the major portion of which is wound on a primary reel, and the remainder of which is wound on a secondary reel. The amount is less than that required to completely fill the tubing, thus providing a slug of fluid material in the tubing on the primary reel and a vacant space in the tubing on the secondary reel. The amount of tubing on the secondary reel is calculated in advance to be equal in length to that portion of tubing required for the production of heat-sealed closures along the length of the tubing. The slug of material is displaced toward the secondary reel, thus creating a vacant space at the end of the tubing on the primary reel, and the tubing is rewound onto the primary reel.