Blending
The aim of blending is to ensure the resultant top is as even and uniform as possible across all characteristics throughout its entire length. Blending can occur at several points during early-stage processing. Consignments, in bales of greasy wool assembled for scouring, are arranged in order so the component lots are randomized before the bales are opened.
The bales are fed to the opening line with the homogeneity of final top properties in mind.
The bales are opened in a bale-breaker. This is usually followed by more openings, such as double drum machines, to break the wool into approximately staple courses and remove some of the dirt. Many opening machines are also designed to ensure some mixing of the components of the blend. Most commonly the entire lot is re-blended as a course in the scoured form in a blending bin. The output of the scour is loaded into the bin in horizontal layers and then removed in vertical slices.
Blending after Scouring
When blending occurs after opening and scouring the output of the scour is loaded and stacked into the blending bin in horizontal layers. In the image below colored layers have been used to demonstrate the effect.
The wool is then moved to the next process by slicing the stack like a cake, before feeding the wool into the various processing machines. This ensures each slice contains all the different fiber qualities and the end of the lot is the same blend as the start of the lot.
Blending also helps to open the fiber staple and remove the initial dirt.
As stated earlier, the aim of blending (before and after scouring) is to ensure the yarn is consistent in composition and color and will produce the best quality yarn for the lowest price.
