Pressure overflow fillers deliver a quantity of free flowing liquid product into a container until the level reaches a specific fill level.
Pressure overflow fillers deliver a quantity of free flowing liquid product into a container until the level reaches a specific fill level.
Although there may be slight variations in the sizes or shapes of bottles and jars, it is frequently desirable to have the fill line at the same height on each container so that all of them appear to be filled exactly the same when they are on the display shelf. Some manufacturers deliberately add extra product and overfill some of their "see through" containers in order to improve their appearance and to guarantee that all of them contain at least the minimum desired amount of product.
Molding and forming techniques can cause minor irregularities in the sizes or shapes of rigid glass and plastic bottles and jars, and some semi-rigid containers may also change their shape and volume slightly during the filling process. It is frequently more economical to use additional product in the oversized containers than it would be to more closely control the forming processes. Constant level filling techniques compensate for the minor changes and variations in the containers and produce the uniform appearance that is important in the sale of many products in ?see through? containers.