In many ways these are simple designs, however they come with complexities and limitations due to a number of moving parts. Maintenance requirements are typically high to ensure reliability and availability, but over 20-30 years deterioration is inevitable.
A gearless direct drive motor system, such as those available from ABB, bring benefits and savings to the user, particularly when it becomes a ‘connected drive’ through digital solutions. These direct drive systems are based on a permanent magnet motor and connect directly to the production equipment without a gearbox. ABB has developed and delivered this technology to a multitude of pulp and paper mills around the world and several advantages have been identified from seeing direct drive systems in action. These are energy efficiency, precise torque control, reliability, safety and security, lower engineering costs and reduced maintenance.
Removing the gearbox from the equipment set-up and replacing its functions with a modern, fit-for-purpose alternative coupled directly to the paper machine has proven to be practical and efficient. A gearbox suffers from energy losses during mechanical movements, which means higher energy consumption. When the drive is directly attached to the production machine using the permanent magnet technology, energy consumption is reduced.