Ultrasonic sensors are a reliable solution for non-contact liquid level measurement, but chemical compatibility is often overlooked during selection. In applications involving solvents like ethyl acetate, the housing material can determine whether the sensor performs long-term or fails prematurely.
Many standard ultrasonic sensors use PVC housings. While PVC works well in general industrial environments, it does not hold up against certain solvents. Exposure can lead to material degradation, which ultimately affects sensor reliability and measurement accuracy.
Even though ultrasonic sensors do not contact the liquid, the housing and sensing face are still exposed to vapors and ambient conditions. In solvent-heavy environments, this exposure can be just as aggressive as direct contact.
For these applications, more chemically resistant materials are often required. A PTFE housing and sensing face provides improved durability compared to PVC, while maintaining consistent sensing performance. In more demanding cases, engineers may look to fully custom solutions using materials like PTFE to ensure long-term compatibility.
A common example is measuring fluid levels in drums or barrels containing solvents. These installations often require both chemical resistance and a practical mounting solution, such as a 2-inch NPT connection. Matching the housing material and mechanical fit to the application is what ensures stable, repeatable measurement over time.
In many cases, these environments also introduce hazardous area requirements. Intrinsically safe designs are used to limit electrical energy so that ignition cannot occur, even in the presence of flammable vapors. This makes both material selection and system design equally important.
The takeaway is straightforward. Ultrasonic sensing is a strong fit for chemical level measurement, but only when the housing material is matched to the environment. If the material fails, the sensor fails.
Have a chemical application that standard sensors can’t handle? Contact Migatron to discuss a semi-custom solution.