Adjustment of the spacing between the 2 cylinders of the mill housing is ensured through screw/nut systems in which the screws swivel under torque in :

• 2 worm and wheel reducers to adjust the horizontal housing .
• 4 worm and wheel reducers to adjust the vertical housing.

Worm and wheel reducers used for tightening rolling mill housing have the following features :

• Steel casing.
• Hub of slow speed shaft made of steel or GJS cast iron with big bore and 6 or 8 wide parallel side grooves.
• Lubrication through oil circulation.
• Groove lubrication

Synchronisation of reduction gears is ensured by the means of one drive only and a clutch system to adjust parallelism of cylinders.

Robustness and design of the casing must be compatible with the high torque that is transmitted at the moment of release and with axial efforts generated on the hub of the slow speed shaft by the action of the tightening screw under load.