A balefeed, sometimes called a hopper, is a very common way of introducing fiber into a non-woven line fiber system. Staple fiber is synthetic fiber that has been cut to a consistent length and then pressed into bales. The bales could also be cotton or another natural fiber. The fiber in these bales is very compressed and needs to be opened and blended with other fibers before it is presented to the card which forms it into a web. A balefeed usually consists of a device to lift the bales into the balefeed, an apron to hold several bales, a spiked uplift apron, a stripper roll, a doffer roll, and controls.
Often three or more balefeeds are placed side by side so that the fiber coming out falls onto a conveyor. To facilitate blending of various fibers, weigh pans can be fitted on the output of the balefeeds. These are usually attached to load cells and the whole process is controlled by a PLC. The balefeed runs until the predetermined amount of fiber fills the weigh pan. Each balefeed drops a percentage of the blend. The conveyor indexes under the balefeeds between drops so each drop is deposited on the previous drop.
If weighing is not necessary, the balefeed can be operated with the weigh pans in an open position. This is call volumetric mode and the balefeed will output considerably more fiber than in weigh pan mode.