Abstract: Methods and apparatus for dispensing a predetermined fixed amount of pre-stretched packaging material to a load are disclosed. An amount of pre-stretched packaging material to be dispensed by a packaging material dispenser is determined based upon the girth of the load to be wrapped. Once the amount of packaging material to be dispensed is determined, a ratio of relative rotational speed to packaging material dispenser speed can be set and mechanically controlled. In an alternative embodiment, the ratio is electronically controlled.

Abstract: A method and apparatus for dispensing a predetermined fixed amount of pre-stretched packaging material based upon load girth is disclosed. A non-rotating ring carries a belt driven by a motor. A packaging material dispenser is mounted on a rotating ring, and the rotating ring may include a pulley that connects to the band, such that the rotating ring is driven by the drive belt. Based upon the girth of the load to be wrapped, an amount of pre-stretched packaging material to be dispensed for at least a portion of a revolution made by the rotating ring is determined. Good wrapping performance in terms of load containment (wrap force) and optimum packaging material use is obtained by dispensing a length of pre-stretched packaging material that is between approximately 90% and approximately 120% of load girth. Once the amount of packaging material to be dispensed per revolution is determined, a ratio of rotating ring drive to final pre-stretch surface speed (i.e.