FAQ – Purisan Mixers

Purisan™ Kynar® Industrial Mixers


Are other Purisan™ Kynar® industrial mixer styles available?

Right now we are delivering marine style impellers in 4″, 5″ and 6″ diameters with 0.75″, 1.0″ and 1.25″ diameter shafts. Shaft lengths are available in 12″ increments. We plan to extend these impeller sizes to 2″, 3″ and 7″ diameters and offer a 0.375″ and 0.5″ diameter shafts. After these products are complete we will begin offering additional designs such as magnetic and hydrofoil impellers. Contact us if there is an impeller design you would like us to consider.

Are powder coatings a bad approach to protecting mixers from corrosion?

No! In fact we use Kynar® PVDF to powder coat the mixer shaft. However the impeller portion of the mixer is a different story. The coated surface on the leading edge of the impeller is rapidly worn through leading to exposure of the metal substrate resulting in corrosion and process contamination. Even the thickest coatings typically last for no more than a year in the best environments and can fail due to wear in a matter of months on a mixer operating in particulate-rich solutions.

I have a custom mixer design that requires a USP Class VI material. Is this something that Nile Polymers can provide?

Yes! We know a lot about Kynar® PVDF injection molding, Kynar® PVDF extrusion and Kynar® PVDF powder coating. We would be very interested in reviewing your design proposal. Please contact us with all the details.

Can't you make the shaft out of solid PVDF? Why does the Purisan™ shaft have a stainless steel interior?

Stiffness. The 316 SST steel shaft helps minimize wobble and run out at the bottom of the rotating mixer. This shaft is made from high-tolerance pump shaft quality (PSQ) steel. Young’s Modulus is a measure of material stiffness. Steel has roughly 100 times the stiffness of PVDF but lacks the corrosion resistance of PVDF. We use PVDF to powder coat the exterior of the steel shaft to a nominal thickness of 1mm (0.040″). The Kynar® PVDF powder coating is made from the same material used for injection molding of the Purisan™ Kynar® PVDF impellers and will provide a long-lasting corrosion barrier.

How soon will my order ship?

Off-the-shelf items will ship within 24 hours of order placement. If we can’t meet this deadline we will contact you with a revised shipment date.

Do the materials for the shaft and the impeller have to be identical?

No. Our 4″, 5″ and 6″ Purisan™ Kynar® industrail mixers have 16mm internal coarse threads. These impellers can be mounted on any shaft with compatible threads. The inverse also applies: a Purisan™ shaft can be mounted to any impeller with matching 16mm threads.

Why is the Purisan™ Kynar® PVDF impeller threaded?

A threaded connection is the best way to lock the stainless steel shaft onto the impeller. Concerns about contamination are eliminated by using an FKM fluoroelastomer gasket between the impeller and shaft.  In case of damage or change in process conditions, the mixer can be easily disassembled and mounted with a different impeller or a replacement shaft. This is a 30 second change out and not a five week replacement! Contact us for more details.

Can I get a copy of your ISO 10993 Cytotoxicity test report for the FKM fluoroelastomer?

Yes. Please contact us and we will get this sent out.

What kind of warranty comes with the Purisan™ Kynar® mixer?

All Purisan™ Kynar® industrial mixers or parts are guaranteed free from defective material and workmanship for a period of twelve (12) months from date of shipment, under normal use and service. Nile Polymers will repair or replace, at its option, any item which is found to be defective and is within the warranty period, provided that the equipment is shipped, with previous factory authorization, freight prepaid, to Nile Polymers in Centerville, UT, USA. All return shipments are made F.O.B. Nile Polymers. Nile Polymers is not responsible for removal, installation, or any other incidental expenses incurred in shipping the equipment to or from Nile Polymers.

NOTE: Any modifications or corrective work done to the equipment which was not specifically authorized in writing by Nile Polymers shall void this limited warranty, and Nile Polymers shall accept no liability for any of the corrective work or expenditures which were conducted without its prior, written authorization. Nile Polymers shall not be held liable for any further cost, expense, and labor to replace equipment and replaceable parts, direct, indirect, or consequential damages.

With the exceptions of the limited warranty set out above, there are no other understandings, agreements, representatives, or warranties implied (including any regarding the merchantability or fitness for a particular purpose or use), not specified herein, respecting this agreement or equipment, hereunder. This policy states the entire obligation of Nile Polymers, Inc. in connection with this transaction.

Please contact us with any questions about the Nile Polymers Warranty Policy at info@nilepolymers.com. Should you have equipment that requires attention in regards to warranty, please contact us to authorize a course of action for your equipment. We understand that downtime is frustrating and costly; we will work with you to establish a prompt solution.