Back To Landscape

Main Conveyors to Primary Screen


Conveyors feeding crushed rock to a screen


Gearbox failure, maintenance costs


A customer had an old, alignment-free, parallel shaft unit that utilized a swing base and hollow output quill of 9-15/16". The conveyor was moving crushed rock at 600 FPM at a rate of 1,200 TPH. Over time, the unit began making a great deal of noise. The operator was concerned that the reducer would fail, shutting down the screening process.


Replace the worn unit with a new TorqTaper® Plus 608SMTP25 reducer, sheaves, belts and guard. Also included was a 7.0 rigid/rigid coupling with special pilot ring in a line bored 9-15/16" shaft modified for keyless mounting and with a B-Loc for slip-fit mounting.


Because a 9-15/16" shaft was not going to fit into the 608 unit, a full rigid coupling was used to create a shaft extension and adapt to a 6-1/2" diameter, 29" long stub shaft, mounted to the existing head pulley. The customer did not have to turn the shaft down or remove the existing head pulley and bearings to accomplish this work. This amounted to a significant savings in maintenance costs by not having to remove and replace the entire machine. Also, the use of a B-Loc hub allows for work on parts in a machine shop, simplifying replacement or installation in the field.