there may come a time in a casting floor (indeed we faced, and i used pneumatic rotation twice), when we have uncontrolled flow of liquid steel from ladle (may be due to slidegate through, or ladle lining through or slidegate cylinder closing failure).
during those times, emergency rotation command can be issued to take ladle to the charging position where the liquid steel can be safely dumped into an emergency ladle kept for safety.
sometimes accessing emergency rotation may take a little longer than reaching a pneumatic rotation system provided as an extra safety feature in modern casting platforms.
the following pictures show one such installed in a caster which was not yet commissioned when these pics were taken.
on the left side is the regularly used electrical motor, that has a discbrake mechanism to hold the motor still ( and hence the turret) from rotating when it is expected to stay put.
there is a rotary encoder nearby the planetary gear mechanism that tracks the position of rotation of the turret from zero to 360 degree as the turret turns during ladle changes.
at the bottom is a pneumatic switch which should stay healthy so that the brake can be engaged/disengaged whenever necessary for rotation.
on the right is the pneumatic motor connected to the same shaft that drives the planetary gear mechanism of the turret. the pneumatic motor has two instrument-air (IA) lines attached with it. one for clockwise and the other for anticlockwise rotation.
normally there would be an accumulator tank which stores IA in enough quantity to turn the turret at least 5 to 6 times and that tank is further connected to a regular IA line supply that runs all along the shopfloor.
during those times, emergency rotation command can be issued to take ladle to the charging position where the liquid steel can be safely dumped into an emergency ladle kept for safety.
sometimes accessing emergency rotation may take a little longer than reaching a pneumatic rotation system provided as an extra safety feature in modern casting platforms.
the following pictures show one such installed in a caster which was not yet commissioned when these pics were taken.
there is a rotary encoder nearby the planetary gear mechanism that tracks the position of rotation of the turret from zero to 360 degree as the turret turns during ladle changes.
at the bottom is a pneumatic switch which should stay healthy so that the brake can be engaged/disengaged whenever necessary for rotation.
on the right is the pneumatic motor connected to the same shaft that drives the planetary gear mechanism of the turret. the pneumatic motor has two instrument-air (IA) lines attached with it. one for clockwise and the other for anticlockwise rotation.
normally there would be an accumulator tank which stores IA in enough quantity to turn the turret at least 5 to 6 times and that tank is further connected to a regular IA line supply that runs all along the shopfloor.
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