Sand goes directly to the molding machine hopper. A probe in the hopper signals the Simpson Multi-Mull when the hopper is full and the feed system automatically shuts down. Then when more sand is needed, the muller is already full of prepared sand and may be restarted immediately. Better sand consistency is another key benefit of the Simpson Multi-Mull. As a result, some batches are undertreated and some are overtreated.
Sand moves in a figure-eight pattern through the mixer.
A portion of prepared sand is constantly recirculated back to be mixed with shake-out sand entering the machine. With the Simpson Multi-Mull, no time is expended batching, charging, discharging or wetting out the sand. All operating time and work energy are concentrated on mulling sand. Expensive, intermittent peaks and valleys of power consumption are leveled out for constant energy consumption at optimal levels. In the event of a catastrophic overload, the Simpson Multi-Mull features a breakable shear pin located in the crosshead assembly that protects drive train components.