"I guess need bigger pump to transfer out whole quantity within 48 hours." You can get AODs for that flow but the pressure is important, too. And the energy consumption is pretty high but if this is an intermittend operation you'll be find with an AOD, especially because these pumps are not that...
CE marking acc. to the European Machine Directive is only about safety, nothing else. The supplier must provide a documentation which allows a safe installation, start-up, operation, shut down and maintenance. If there are no safety issues which have to be considered during maintenance, he will...
If the vendor knows the fluid data incl. vapor pressure, he will be able to calculate NPSHA. If not, he might not be the right vendor. NPSH might not be an issue in this specific case but the vendor should be able to proof that with a short NPSHA calculation which shows that NPSHA > NPSHR. If...
Why not Polypropylene? You did not mention the temperature but up to 40 °C PP is still a good choice and much cheaper than PVDF. Not sure what diaphragm pump manufactureres you have checked but ABEL and FELUWA might be worth to look at. I do not think that they must offer a double head pump for...
"Thus if you don't allow for a full flow bypass / relief in the event of locked outlet flow, the PD pump can create a very high pressure until the motor stalls." Right - if you are lucky. If not something else will break or burst and that can be much more dangerous than a stalled motor.
Yes, that is a pressure switch which starts and stops the pump depending upon the loads. It takes care of a constant pressure, reduces peaks and can even act as a no-flow protection.
"Yes, but the CE mark together with the Ex mark means atex, doesn't it?" Yes, it does. But you must then also have a Declaration of Conformity from the manufacturer.
CE mark does not mean ATEX. CE mark means compliance with an (any) European Directive which can be PED or ATEX (to name just two examples). And yes a pressure vessel can be subjected to ATEX. If it falls under PED than PED rules ATEX. If it does not fall under PED (as you know PED has...
First you must keep in mind that pressure is the result of flow of a certain liquid through a certain pipe (material, diameter, length) and not vice versa. Simply speaking (and physically not correct) it is friction which leads to a certain pressure. The attached tutorial is a lot to read but...
When I type "molton sulphur pump" in Google the manufacturers Goulds, Peerless, Rheinhuette and Hayward Gordon appear on the first page (plus a few others). At least all of these four are what I would in general call a "top supplier".
Everybody can supply IE3 motors but only a very few manufactures have a cpl. range of IE4 motors, especially for the small sizes. If you do not have a manufacturer preference, I would not specify IE4 motors because it will be significant price adder. Companies like ABB, Siemens and VEM have IE4...
What kind of pump are you using? A centrifugal pump or a positive displacement pump? How is the VFD adjusted, manually or is there any signal which tells the VFD to speed up or slow down?
CE marking? I doubt that this is done. Probably material certificates and batch (charge) number on the raw material but I have never seen a CE on a raw material.
Go with a diaphragm pump with PTFE diaphragms, balls and seats. An air driven pump for that flow is really cheap and works well. If compressed air is not available or if you cannot accept the pressure depending flow, search for "electric diaphragm pump". They are of course more expensive because...
