Multi-Cooler Discharge Door Upgrade

 

• Improvements in both control methodology and mechanical elements
• Accurately and continuously measures the true energy usage at the drive motor
• Accurately determines the energy required to retain a constant mass

The primary design objective of the Simpson Multi-Cooler was to provide sand stability through cooling and preconditioning using less space and more control than any other cooler system.

Users reported the opportunity to improve the performance of the Multi-Cooler due to the following issues:

1. To maintain optimal performance of the cooler during major changes in sand demand it is required that an operator intervene to manually reset mechanical adjustments of the inner discharge door mechanism. This requires a skilled, knowledgeable operator and some cooler downtime. In many foundries the adjustment was just not done, and system performance suffered. Major changes in sand demand could result from a change in the number of active molding machines requiring sand due to a major maintenance event or reduced production schedules. 
   
   
2. Prior to the year 2000 the supply of most Multi-Coolers took place with separately provided black box moisture controls resulting in redundant components (panels, PLC’s, etc.) and minimal interfacing between the cooler and its primary process control. The redundant controls increased the cost of operator training & maintenance and reduced the overall performance of the system.
   
   
3. Unbalanced electrical loads and fluctuations in power demand often create variations in the available power. Sometimes, those variations can be as much as 15%. These variations reduce the true power consumed by the Simpson Multi-Cooler drive motor, thereby reducing its efficiency. Monitoring amperage alone typically does not reveal the problem and controlled retention suffers. For the demanding conditions of modern foundries, the old amperage monitoring method, discharge door design and control logic were not precise enough.

The discharge door and its control logic has been updated to meet these challenges. The new discharge door system improves control over door actuation and operation. The new door allows any foundry to easily enhance performance of their Simpson Multi-Cooler.

The new door consists of a single, vertical discharge gate. The door is positioned by an electro-mechanical actuator in response to the three-mode control loop. The actuator, complete with a variable frequency drive for positioning, is designed to quickly respond and locate the door to retain a constant retention time at all times manual intervention. This significantly improves the performance of the Simpson Multi-Cooler during varying foundry conditions. More consistent sand properties result, even when slight fluctuations in sand composition and demand occur. If more dramatic changes in retention time are required (for example, when one of the two or more molding machines on the sand plant are taken off-line), the new discharge door system can be more quickly and easily balanced.

For existing Simpson Multi-Cooler installations, the system has been engineered to easily replace the old door. For new installations, the redesigned discharge door system comes standard on all new Simpson Multi-Coolers.