Stainless-Steel WQ Pumps for Corrosive Industrial Wastewater

Standard WQ pumps use cast-iron wetted parts, comfortable in roughly pH 6-9, which is fine for most domestic and general industrial sewage. Outside that band, corrosion turns from a theoretical concern into an actual service-life problem, which is where the stainless-steel option comes in: 304 grade as the default, 316 where chloride exposure is a factor, such as brined food-processing waste or coastal sites.

The swap is materials-only. Hydraulic performance at any given frame size stays identical to the cast-iron version, and it’s available across most of the range, including WQ-G grinder variants. The catch is that it isn’t field-retrofittable; grade needs specifying (304 or 316) at order time. And the limit deserves an honest mention: for strong-acid or very high-chloride conditions, even 316 stainless has a ceiling, and a specialized anti-corrosion pump design is the more honest recommendation at that point.