Valve balls play a key role in AODDP’s fit, form, and function. Resting on the valve seat, the balls travel north to south and provide a seal, effectively creating the opportunity to suction lift from tanks and other containers found below or at the level of the pump. The valve ball material should be selected based on the media being pumped, from low to high pH, percentage of solvent or acid content, etc. Rubber options include Neoprene, Buna, EPDM, and Viton. Thermo-plastic options (TPEs) featuring Santoprene and Hytrel are also available. PTFE is an excellent option to handle a blend of the most aggressive chemicals. The NOMAD Chemical Compatibility Chart (also found on the JDA GLOBAL website) provides guidance on temperature limitations for each material, as well as providing a large selection of material selections based on historical usage with individual materials or compounds.