Not all chemicals are compatible with all chemically resistant materials. For this reason, all metering pumps have differnet options when it comes to specifying the material selection for the Liquid End. (The liquid end refers to the pump head, foot valve, injection valve and tubing, i.e. all materials which come into direct contact with this chemical when dosing).
Metering (dosing) pump heads are usually PVDF, PP, PVC or SS, whilst the seats and seals are usually Viton or EPDM. Ball checks are either Ceramic or SS, and Tubing is either LDPE, PVDF or PTFE.
EMEC pumps have 2 standard configurations that cover most chemicals that you will be dosing, i.e. PVDF head, Viton Seals, Ceramic balls, PE tubing - suitable for most Acids, Chlorine, Biocides, Inhibitors etc PP head, EPDM Seals, SS balls, PE tubing combination is ideal for Sodium Hydroxide (i.e. Caustic Soda) or most Boiler dosing chemicals
There are many "Chemical Compatibility Charts" on-line where you can check the compatibility of each material against the Chemical you will be dosing.
It is always important to refer to the manufacturer SDS for each chemical for safety reasons and also to wear the appropriate PPE when handling any chemicals.
Tips when installing :
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- Request EPDM (Dutral) Seals (O-rings) if dosing Caustic (also for boiler dosing applications).
- Request FPM (Viton) Seals (O-rings) if dosing Acid
- Request PVDF heads & tubing for dosing Sulphuric Acid (if greater than 98.5%)
- Always check chemical compatibility charts (downloadable here)
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- Part numbers of pumps with EPDM seals have “EP” on the end of the code
(e.g. EMEC VCO 15 02 EP) - EP Pumps have white nuts for easy identification
- Part numbers of pumps with EPDM seals have “EP” on the end of the code
Other questions to ask are: What flow rate do I require and what pressure am I pumping into? (click here) What external inputs do I require, if any? (click here) What temperature am I dosing into? Is my preference for pump configuration Foot Mount or Wall Mount?
