The next product spotlight from PCC will be a special two part blog on our line of Vacuum Receivers for material handling. Today’s entry will focus on proper receiver sizing and how it affects the blending system.
PCC manufactures a complete line of vacuum receivers for use in pneumatic conveying of plastic material. The RN Series is designed for plastic pellets and the RP Series for dusty materials like plastic regrind. When coupled with a vacuum pump and sequencing panel, vacuum receivers can provide automatic loading of blenders with multiple hoppers, surge hoppers, storage bins or other devices. Since a typical conveying system includes multiple receivers, for the system to operate efficiently, the receivers must be properly sized.
Properly sized receivers are even more critical in the case of continuous, loss in weight gravimetric blenders where the blender hoppers are sitting on load cells. In normal operation, the blender monitors the weight of the material in each hopper and adjusts the material feed rate accordingly to provide an accurate blend of material. When the receiver provides a dump of material to the hopper this can disturb the weight monitoring process. To compensate, the blender senses this disturbance and goes into coast mode temporarily. A properly sized receiver will provide a dump size that fills the hopper completely, without over filling, and minimizes these periods of disturbance providing increased accuracy. Over filling, caused by an over sized vacuum receiver, also disturbs the weighing process since the material backs up in the receiver and continues to drain into the hopper as material is removed.
Check back this Thursday for Part 2 on our Vacuum Receiver Spotlight, where we will discuss the various options available for PCC vacuum receivers.