Titanium would be the best metal option.

Thank you, I will research and see where titanium is available for me to purchase.

Have a wonderful evening.

If the temperature is not hgher than about 80ºC, polypropylene will work quite well.

Er, <...polypropylene...> is not a <...metal...>.

This may work for you. Don't know the size of your operation.

From:Midwest Supplies - The Stainless Steel Mix Stir

Titaninum is expensive and difficult to work with. But would certainly work. So would Hastalloy C-276.

So stainless will not breakdown in muriatic acid?

If not, I have stainless rods in the shop that I could use, and make my paddles out of stainless plates with a few drilled holes in the plates. I can weld my stainless.

Please advise.

Over time you may see some erosion. Depends on exposure time and quality of rinse after use. I used to build acid etchers for PWB industry. Ti is better for continuous use, but this looks like stir 5 minutes, rinse, put away til next time.

Maybe I'll see you at Oaklawn in April.

Yes, it will only take about 5 minutes each time they stir, which is twice a week on a 100 gallon tank.

Rinse and scrubb with water?

Let me know your dates later and if I am not in Green Bay those dates, I would be glad to meet you there one day.

ADMIN: Deleted Content

From the Rules: Do not post personal contact information on the forum space. You can share this information via the forum's internal messaging system.

Hi jhunter1972,

Why does it have to be metal? What size would the blade need to be? I think that the easiest solution would be to purchase a rubber or Teflon-coated impeller.

See here, here, and here.

Mike

Guess I was thinking of durablity for the long haul, it needs to be rod that is 5' long with cross pieces, around 8" to 12" in length, at different angles on the lower 3 feet of the rod.

The coated metal does sound appealing if I can locate something along these lines.

At least 2 of the links I gave you have coatings as an option for their impellers.

In that concentration a SS-316L will survive you if you take it out after use.

The wetted portion (in the acid) need not be a rod. you can use a thermoplastic pipe the will give you the strength for mixing and allow the paddle like horizontal portionsyou need. Is PVC an allowable material if not PTFE (teflon) or Kaynar are worth looking at.

Contact Duriron company in Springboro, Ohio (USA) and see what they would charge to fabricate 2 or 3 of your stirrers (so you have spares on hand) out of pure teflon. They work with that material for custom products every day.

What would be the ideal material of construction for a hydrochloric acid plant?

Q: What would be the ideal material of construction for a hydrochloric acid plant? Would you recommend using galvanized steel, which is painted with three layers ( two epoxy + one final coat of acrylic), the total thickness is maxi 180 μm?

A: From your question it sounds like you are talking about a plant that manufactures hydrochloric acid. This is a complex operation and might involve the use of several different materials of construction depending on the specific equipment in question. However, some general advice can be given regarding the appropriate materials of construction for hydrochloric acid service.

Most metallic materials are not compatible with hydrochloric acid including aluminum alloys, iron and steel, galvanized steels, and stainless steels. Hastelloy alloy B-2 has some resistance as long as oxidizing impurities are not present. Ni-Cr-Mo alloys like the Hastelloy C family can be used in some applications as long as the concentrations and/or temperatures are not too high. Tantalum offers good resistance to hydrochloric acid but it is expensive. In general, nonmetalic materials have better resistance to hydrochloric acid than metallic materials. Rubber-lined vessels are commonly used for hydrochloric acid storage. Polypropylene, PVC, PTFE, FEP, PFA, ECTFE, PVDF, and FRP can be used as long as long as recommended temperature limits are followed. While some paint/coating systems may be acceptable they are prone to damage and can allow hydrochloric acid to reach the substrate which is often not compatible. There are many good references available that can provide more detailed information. Examples include MTI Publication MS-3, "Materials Selection for Hazardous Chemicals: Hydrochloric Acid, Hydrogen Chloride and Chlorine" and "Corrosion by Hydrogen Chloride and Hydrochloric Acid" in ASM Handbook Volume 13C, Corrosion: Environments and Industries. For more information on coatings, a good place to start would be Schweitzer's "Corrosion of Linings and Coatings," which is one volume of the three volume Corrosion Engineering Handbook (2nd Edition) set.

Just for your information - almost each rod in metal will do the job -it you have it powder coated with epoxy - we had Test Boxes in Plexi Glass to create different humidity environments. On the bottom was a big plastic pan as for Photo development with in it a mixture of water,with salts and/or acids - in much higher concentrations. always about 2 inches. A frame in regular steel, coated as said - was in there continuously. After 5 years when we locked down the laboratory the originally grey epoxy just turned out to become green and the steel wasn't even reacting.

Have a look at this doc from NIDI

Nickel. Development. Institute. Alloys to resist chlorine, hydrogen chloride and hydrochloric acid

http://www.corrosionsource.com/technicallibrary/nidi/literature/pdf/10020.pdf

S

corrosion & rust prevention

The resistance of materials to corrosion is public domain information.

I want to say THANK YOU to all who shared info with me; I made a Mixer Paddle with the following materials with the info gathered and it works great.

1- 1/2" SS Rod; which I had

10- 7/8" SS Washers for welding the plates to the rod; which I had

5- 1/8" x 3" x 8" SS Plates; which I had

I welded these together on the lower 1/3 of the rod in fashion that would churn the chemicals well.

I then used some Performix brand Plastic Dip (for use with products exposed to corrosive substance)

I used the grinder cutter to finish the top end of the rod so that it would fit into a 1/2" shafted drill.

It works great.

Thanks again for all..