The double-shaft machine discharges larger particles, but the throughput is larger; the single-shaft machine discharges smaller particles, but the throughput is smaller. The principle of single-shaft machine is like teeth gnawing, and the principle of double-shaft machine is like scissors and hooks. From the energy utilization rate, double shaft machine energy consumption is lower, single shaft machine energy consumption is higher.
The first two explanations are more on point, I just add to it.