Nuttall Drivetrain Assemblies for Blast Furnace Slag Granulator

A global designer and manufacturer of slag granulator systems needed heavy-duty drivetrain assemblies for a new steel mill installation. Molten slag is a by-product generated by the mill’s blast furnace during the steelmaking process. The slag granulator utilizes several identical drivetrain assemblies to move the slag slowly on a conveyor while it is subjected to water jets which disperse/convert the slag into small granules. The slag granules are used in a variety of applications including the manufacture of Portland cement.

Nuttall was contacted based on their extensive experience with heavy-duty drivetrain applications. Nuttall engineers worked closely with the OEM’s team to design the overall drivetrain assembly configuration. Nuttall manufactured custom-designed primary parallel-shaft enclosed reducers which featured an input rating of 50 HP @ 1750 RPM with a reduction ratio of 279.258:1.

Nuttall also built Moduline R-Type concentric in-line, shaft-mounted creep drives which are needed to keep the slag moving to prevent hardening when the mill is not producing steel. The creep drives featured an input rating of 15 HP @ 1750 RPM with a reduction ratio of 5.169:1.

The complete drivetrains, including the Nuttall reducers as well as customer-supplied couplings, torque limiters and motors, were assembled and mounted to custom- fabricated pedestal bases by Nuttall technicians. In-house testing of all drivetrains was completed prior to shipping directly to the mill location.

Download a PDF of this article