Cast iron is the right, economical choice for ordinary sewage. But put it in salt water, acidic wash-down, or food-plant effluent full of brine and organic acids, and it corrodes — sometimes within a season. That’s the moment to move to stainless.
The 100GNWQ100-15-7.5S is precision-cast in SS304 throughout, so the whole wetted path resists corrosion, not just the visible surfaces. It handles 100 m³/h at 15 m head on a 7.5 kW motor through a 100 mm outlet, and keeps the same 48 HRC alloy cutting system as our cast-iron line — so it still shreds packaging, gloves and fibrous waste, the things that block food and processing drains.
A seafood processing plant in Thailand was replacing carbon-steel pumps almost yearly thanks to brine. A Haquan GNWQ-S stainless cutter pump ended the cycle — three seasons in the same pit with only routine seal service.
If your effluent is corrosive, salty or food-grade, cast iron is a false economy. Ask us about the GNWQ-S stainless range at sales@haquanpump.com.