Flow Measurement · Electromagnetic Flow Meter · Wastewater Selection
Which Liner and Electrode for Which Wastewater Type: 5 Essential Combinations Every Engineer Should Know
Two electromagnetic flow meters can be identical in every spec except liner and electrode material, and only one of them will survive five years in your actual wastewater. This guide matches the right materials to specific wastewater types, with an interactive selector and a full reference table.
Why "Wastewater" Is Not One Single Chemistry
Municipal sewage, sand laden stormwater runoff, chemical process effluent, and high chloride coastal wastewater share almost nothing in common except the word "wastewater." Each one attacks a liner or electrode differently, and specifying the wrong material for the specific stream you actually have is one of the most common, and most expensive, mistakes in electromagnetic flow meter selection.
This guide focuses specifically on matching liner and electrode material to wastewater type. For velocity sizing, conductivity limits, and grounding requirements, see our companion guide on magnetic flow meter sizing and installation.
Interactive Wastewater Type Selector
Pick your wastewater type below to see the recommended liner and electrode combination.
The 3 Liner Materials at a Glance
Excellent broad chemical resistance. The default choice for corrosive chemical and industrial wastewater streams.
Superior abrasion resistance. The default choice for sand, grit, and sludge laden wastewater streams.
Cost effective and reliable for mild, non aggressive streams. The default choice for general municipal sewage.
Electrode Materials, Ranked by Corrosion Resistance
Full Reference Table: Wastewater Type and Recommended Materials
| Wastewater Type | Recommended Liner | Recommended Electrode |
|---|---|---|
| Municipal / domestic sewage | Neoprene | 316L Stainless Steel |
| Sand or sludge laden wastewater | Polyurethane | 316L Stainless Steel or Hastelloy |
| Chemical / industrial effluent | PTFE | Hastelloy C or B |
| High chloride / coastal wastewater | PTFE | Titanium |
| Extreme corrosion / specialty chemical | PTFE | Tantalum |
| Meter Size (DN / mm) | Flow Lower Limit @ 1 m/s (m³/h) | Flow Upper Limit @ 3 m/s (m³/h) | Ideal Measuring Range |
|---|---|---|---|
| DN25 | 1.77 | 5.30 | 1.8 ~ 5.3 m³/h |
| DN32 | 2.90 | 8.69 | 2.9 ~ 8.7 m³/h |
| DN40 | 4.52 | 13.57 | 4.5 ~ 13.6 m³/h |
| DN50 | 7.07 | 21.21 | 7.1 ~ 21.2 m³/h |
| DN65 | 11.95 | 35.84 | 12.0 ~ 35.8 m³/h |
| DN80 | 18.10 | 54.29 | 18.1 ~ 54.3 m³/h |
| DN100 | 28.27 | 84.82 | 28.3 ~ 84.8 m³/h |
| DN125 | 44.18 | 132.54 | 44.2 ~ 132.5 m³/h |
| DN150 | 63.62 | 190.85 | 63.6 ~ 190.9 m³/h |
| DN200 | 113.10 | 339.29 | 113 ~ 339 m³/h |
| DN250 | 176.71 | 530.14 | 177 ~ 530 m³/h |
| DN300 | 254.47 | 763.41 | 254 ~ 763 m³/h |
| DN350 | 346.36 | 1039.08 | 346 ~ 1039 m³/h |
| DN400 | 452.39 | 1357.17 | 452 ~ 1357 m³/h |
| DN450 | 572.56 | 1717.67 | 573 ~ 1718 m³/h |
| DN500 | 706.86 | 2120.58 | 707 ~ 2121 m³/h |
| DN600 | 1017.88 | 3053.63 | 1018 ~ 3054 m³/h |
| DN700 | 1385.44 | 4156.33 | 1385 ~ 4156 m³/h |
| DN800 | 1809.56 | 5428.67 | 1810 ~ 5429 m³/h |
| DN900 | 2290.22 | 6870.67 | 2290 ~ 6871 m³/h |
| DN1000 | 2827.43 | 8482.30 | 2827 ~ 8482 m³/h |
Quick FAQs: Material Selection for Wastewater
External References
What we learn today
- Liner and electrode selection for electromagnetic flow meters should be matched to the specific wastewater type, not treated as a single generic decision.
- PTFE handles broad chemical corrosion, polyurethane handles abrasion, and neoprene handles mild general duty streams cost effectively.
- Electrode materials range from 316L stainless steel at the low end up to Hastelloy, Titanium, and Tantalum as corrosive severity and chloride content increase.
- Matching material to actual stream chemistry, rather than defaulting to the most resistant option everywhere, keeps both reliability and cost under control.