Impeller Material

[FAIZANYOUSUF]

Hello,

Hope you are fine there. I want to inquire about non-metallic material to be used for impeller. The impeller is to be used for caustic service having 15% concentration.

 

[EdStainless]

Is your caustic sodium hydroxide?
What is your max temp?
Is there a reason to not use stainless steel?
Most plastics (polyethylene, polypropylene, vinyl ester epoxy, PPS and similar thermosets) are fine with NaOH, but you cannot use a silica or glass filled one as the glass will be attacked.


= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

 

[FAIZANYOUSUF]

Yes caustic is sodium hydroxide. Maximum temperature will be around 50 to 60 Centigrade. The reason for not using SS is we are manufacturing impeller with it but its progress is not satisfactory as was expected. Now I want to switch to non-metallic material.

 

[EdStainless]

The tooling to injection mold a PPS impeller is very complicated.
Stainless steel is simple by comparison.
You will need a plastic with carbon fiber filler, it will be expensive and difficult to work with.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

 

[FAIZANYOUSUF]

Can simple propylene be used?

 

[Artisi]

It's not the material that should be your main concern, but the method/complication of manufacture.


It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[lukin1977]

I once had the same application as yours and I used a pump with plastic impeller and housing. The coupling between motor and pump was magnetic. I think they are called Mag-Pumps or something like that

It worked fine