Those of us who work on customer applications routinely get spec requests that some device we’re supplying must withstand any number of extremely aggressive products. The frequent go-to solution is a fluoropolymer such as PTFE, PVDF, or similar since these have exceptionally wide chemical resistance. Unfortunately, fluoropolymers come with a dangerous downside: PFAS, or as many call them, forever chemicals. Customers tell us that fluoropolymers might be perfect for the application, but their company no longer allows their use.

Fortunately, we have a solution: PEX. You’ve probably seen this material at your local hardware big-box store in the plumbing department. Why it works for our magmeters is the topic of my article in the Processing magazine, World’s First PEX Magmeter Liner Improves Operations.

So how can cross-linked polyethylene (PEX) replace fluoropolymers? Don’t underestimate the capabilities of PEX. It has an impressive range of chemical resistance, admittedly not as extensive as PTFE, but it has no PFAS, so it is being adopted by many industry segments where this is critical.

Appreciation for PEX is not new as it is widely used in plumbing applications to replace PVC, and even copper. These capabilities led Emerson to select PEX as a PFAS-free alternative to PTFE for liners in many of its Rosemount™ Magnetic Flowmeters. Emerson is the only supplier offering PEX liners in its products, although PTFE will remain available for those extreme chemical processing applications beyond PEX’s limitations.

This sounds very good generally, but here are some more details.

The same characteristics that make PEX suitable for water and chemical piping apply for magmeter liner use:

• Higher abrasion resistance than PTFE, up to four-times more abrasion resistant than carbon steel pipe.
• NSF/ANSI/CAN 61 approval for drinking water applications.
• Chemical resistance similar to PTFE but covering a wider range of conductive chemicals, so PEX liners can often cover a facility’s entire range of applications, unlike PTFE.
• Process flow temperature range between 0° to 203°F (-18° to 95°C).
• Maximum standard pipe size is currently 8-inch, although larger sizes are under development.

PEX liners are now exclusively available from Emerson in several product series:

• Emerson’s Rosemount™ 8750W Magnetic Flowmeters
• Rosemount™ MS Magnetic Sensor for Slurry Applications
• Rosemount™ 8705 Flanged Magnetic Flowmeter Sensors

The article discusses how PEX liners excel in a variety of applications, especially those were eliminating PFAS exposure is critical.

Emerson’s wide range of magmeters has proven the technology’s versatility and accuracy, while maintaining an affordable price compared to some other measurement technologies. Adding a PEX liner option builds on this foundation, extending the range of practical applications where PFAS requirements are a constraint.

For more information, visit Emerson’s Flow Measurement pages at Emerson.com. You can also connect and interact with other engineers in the Chemical Processing and Water & Wastewater Groups at the Emerson Exchange 365 community.