A very consistent way of chopping is done in a rotary process. A drum with a selected blade count, spaced out to the desired fiber length achieves a very high accuracy.
A predetermined strand count will be fed into the rotary chopping mechanism. The actual chopping is then done by the means of crushing the fiber, rather than cutting it. This is possible, due to the fact that glass fibers are brittle by nature.
By feeding multiple strands at the same time, you can mix fibers with various properties, as well. This allows for a predictive and cost effective blend of fibers with a property mix for optimal efficiency in the following application.
Doing so, blended chopped fibers allow for more cost effective solutions or to create complete new niche markets.
Guillotine Chopping is often done when recycling the waste materials come from the glass fiber manufacturer.
The input material can be “Spin-cakes” or other materials which have not passed the inspections. In order to be able to chop a cake, it is necessary to break it down in smaller pieces. This can be done with a table saw like process. After multiple additional chopping processes, the fibers may have somewhat more random lengths than resulting from a Rotary Chopping.
During the next steps, the fibers can be opened, dried and baled and sent to the next intended application as e.g.
a) mechanically bound, needled into a “Needlemat” for industrial insulation
b) chemically bound into an insulation batting for automotive or commercial or industrial use
c) used as a reinforcement product for panel making