Thermoplastics such as polypropylene (PP) are resistant against most aggressive liquids such as acids, caustic soda, corrosive and hazardous fluids in general. PP pumps are manufactured for complex applications in specific industries. They are constructed so that none of their metal components come into contact with the pumped liquid. Polypropylene has excellent mechanical properties and makes for a structurally sound pump. However it is unsuitable for halogen acids such as hydrofluoric, hydrochloric, hydrobromic and hydroiodic acids. Polypropylene pumps can operate over a wide range of flow rates but a small range of pressures. These are:
• Maximum pumped liquid flow rates between 16 and 901 litres per minute
• Maximum heads of up to 1.5 to 7.6 metres
• Maximum operating pressures 5 to 8.6 bar
• Maximum pumped liquid temperatures of 90 degrees C
Components such as diaphragms and ball valves in Blagdon polypropylene pumps are available in different materials such as:
• Buna-N that can work in water, mild chemicals and hydrocarbons between 10 and 60 degrees C
• EPDM works for dilute acids and caustic solutions but not oils or organic solvents, also in a temperature range of 10 to 60 degrees C
• Geolast works for water, mild chemicals and most hydrocarbons between 10 and 60 degrees C
• Neoprene has excellent resistance to abrasion and is used in the ceramics industry for grouts, clays and dirty waste between 10 and 54 degrees C
• Polyester can be used with hydrocarbons, solvents and oils between 10 and 54 degrees C
• Polyurethane has good resistance to abrasion and is used with dirty water, hydrocarbons and oils between 10 and 54 degrees C
• Santoprene also has excellent abrasion resistance and is used on mild acids and caustic solutions between 10 and 60 degrees C
• Viton works for moving most solvents and aggressive chemicals. It can work at a high temperature range of 24 to 100 degrees C
