This type of conveying system is typically utilized to convey materials that are susceptible to “sliding” or “rolling” degradation or are abrasive in nature and also can be utilized when material segregation is of a concern. Pressure pot dense phase systems typically operate at positive pressures of 25-50 PSIG or negative pressures up to 29” Hg with solids to air ratios (pounds of product per pound of air) of greater than 30:1