The core difference is the concentration and abrasiveness of solids in the fluid being pumped.
Dewatering pumps (Cosmos CDW) are designed for groundwater and site water that carries incidental solids — dirty or muddy water with suspended solids up to 12 mm in size, specific gravity up to SG 1.1, and solids content typically below 5% by weight. Standard steel and aluminium construction is sufficient.
Slurry pumps (Cosmos CSL) are built for fluids with high solids content — 10% to 70% by weight — at specific gravities from SG 1.2 up to SG 2.1. At these concentrations, standard materials wear rapidly. The CSL uses 27% hi-chrome cast iron (hardness HRC 50+) throughout the wetted path to resist abrasion.
| Parameter | Dewatering Pump (CDW) | Slurry Pump (CSL) |
|---|---|---|
| Solids content | < 5% by weight | 10–70% by weight |
| Specific gravity | Up to 1.1 | Up to 2.1 |
| Particle size | Up to 12 mm | Up to 70 mm |
| Wetted materials | Aluminium alloy / SS | 27% Hi-Chrome Cast Iron |
| Typical application | Construction groundwater, mine dewatering | Mine tailings, ash transfer, sand pumping |
Use the CDW for site water removal. Use the CSL wherever the fluid has visible sediment concentration or comes from a process stream (ash pond, sand trap, coal runoff sump).
