Dosing pumps are subject to certain temperature limits due to their operating characteristics and direct contact with various liquids. These limits depend on the material of their internal components (head, diaphragm, O-rings, valves) and the type of liquid being pumped.
ITC Multifertic Technical Article
The most important temperature restrictions when using dosing pumps are:
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Liquid temperature limit
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Dosing pumps are typically designed for liquids with temperatures between 0 and 40 or 60 °C.
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More robust industrial models (made of materials such as PTFE, PVDF, stainless steel or Hastelloy) can process liquids at temperatures from 90 to 120 °C .
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At higher temperatures, special designs (cooling jackets or cooling systems) are required.
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Ambient temperature limit
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Most dosing pumps can be used at ambient temperatures from -10 to 45 °C.
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In very cold conditions (below freezing), heaters should be used, and in very hot conditions (over 50 degrees), ventilation or cooling systems should be used.
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The influence of temperature on injection accuracy
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Changes in temperature lead to a change in the viscosity of the fluid, which in turn results in a change in the actual pump performance.
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The expansion and contraction of materials such as PTFE or diaphragm rubber can result in reduced accuracy or even leaks.
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Physical limitations related to temperature
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EPDM or NBR membranes: for low temperatures (max. 60–80 °C).
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PTFE membrane: temperature resistant up to 100–150 °C.
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The pump head is made of stainless steel or Hastelloy: resistant to high temperatures and aggressive liquids.
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Plastic (PVC, PP): normally limited to 40–60 °C
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