Jim Zinski explains the basics of pneumatic systems, pressure drop & pump selection
Vacuum pumps are the heart of any resin conveying system – providing the vacuum to pull resin through your system from each source to each destination. Vacuum pumps are the most effective way to move pellets, regrind and many powders through a system. They are reasonably priced, relatively quiet and because they pull resin through the lines, they help contain dust within the system.
Note that the vacuum is used to create an airstream in the material lines which pulls the material through the conveying lines from a source to a destination. An integral filter and an external cyclone dust collector are used to keep stray dust and fines out of the vacuum pump. A highly effective cyclone dust collector is an important component to ensure extended pump life. It should remove 99% of dust and fines from the airstream.
There are several types of pumps from which to choose and multiple sizes within each type. You really need the advice of a resin-handling specialist when choosing this important component of your handling system.
Be sure to choose the pump carefully and allow for excess throughput capacity. Various pump types are designed to work with line sizes from 1”– 6” diameter and provide from 8-16” Hg of operating vacuum.See Vacuum Pump Comparison Chart.