... to improveII. Structure explanationPNJ, PNJFA-plastic pump parts and components are the main body, covered pump, impeller, the axis, the former ... the sheath, brackets, vice impeller or packing seals,etc.Pump body, covered pump, bracket and so on, made of cast iron with ... time to improve the structure of the pump, parts and components are: pump, pump cover, pump seat, frame, the original structure of ...