DC SCR / thyristor drives, field controllers, and DC motors remain common in industries such as metals, cranes, mining, and printing. The current trend is to replace DC systems with new AC drives and motors to reduce maintenance overhead.
However, replacing DC systems can often be a significant task that requires the machinery to be taken out of service for an extended period while mechanical and electrical rework is completed.
So, utilizing existing DC motors and upgrading the DC drives can be the most attractive option. DC motors are usually well built and capable of offering many more years of service to help lower project costs and minimize disruption and risks.