Solving the temperature resistance issue of metering pumps
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The existing Pasfida metering pumps are available in PP and PVDF materials. The manufacturer recommends that the temperature not exceed 60°C, but it has been found that both of these materials can withstand temperatures above 110°C. Current requirements: flow rate of 300 L/h, pressure of 0.1–0.2 MPa; the medium is brine with a temperature of around 105°C. Is it possible to use these pumps in such conditions? Or are there any other pumps that can be used? Previously, screw pumps were used, but the stator’s heat resistance was insufficient, causing it to fail very quickly.
For diaphragms, one can’t just focus on the material of the pump head; the diaphragm itself also needs to be heat-resistant.
If the temperature is too high, the pressure resistance of the diaphragm will not be sufficient. What is this upper temperature limit? Do you have any reference data?
It doesn’t matter if the diaphragm is at 105 degrees; the material of the pump head can be replaced, right?
The strength of engineering plastics decreases significantly at high temperatures. There are also some oil seal types; if they are made of NBR, the maximum temperature tolerance is generally around 90 degrees. Pasfida’s diaphragms are composite diaphragms – if they are a combination of NBR and PTFE, they cannot withstand temperatures of 105 degrees. If it’s a pure PTFE diaphragm, then with such low pressure, there should be no problem.
A metering pump can be used. Choose the DZJ 320/0.5 mechanical diaphragm metering pump; it operates at 105 degrees. The diaphragm isn’t a major issue, but the maintenance interval needs to be shorter compared to when operating at normal temperatures.
A stainless steel pump head can be chosen; this temperature is no problem
Replace with a stainless steel pump head and a stainless steel diaphragm; 105 degrees is no problem.
The application scope of PTFE mechanical diaphragm pumps requires attention to the control of the transmission lubricant temperature.