Distribution and hardening of sand around cluster of polystyrene models in lost-foam casting process, employs controlled triaxial hydraulic vibrators and adjustable air suspension

摘要

The casting box (1) is vibrated in three dimensions along x, y and z axes. The process is controlled in real time by desired- and actual value comparison. It comprises continuous or layered filling of sand into the box after introducing the cluster of polystyrene foam models, the three dimensional vibration being continuous or interrupted. The vibratory movements are each precisely linear and are produced by servo-hydraulic vibrators (6, 7, 8). The process parameters of each individual hydraulic vibrator are all controlled independently of one another and comprise vibration: frequency, amplitude, force and duration. Control is automatic during running, from sensors measuring molding sand: density, level and acceleration. As the casting box is filled, its weight increases. The pressure in the air-spring (3) mountings of the casting box clamping frame (2) is adjusted accordingly. An independent claim is included for corresponding equipment.