Impeller stainless steel casting

The impeller is the rotating part of a centrifugal pump that transfers energy from the motor driving the pump to the fluid being pumped by accelerating the fluid outward from the center of rotation. When the outward movemen

Why is the impeller made of stainless steel casting?
The basic alloying elements for any nickel-based or stainless steel casting are chromium, nickel and molybdenum (or "molybdenum"). These three components will determine the grain structure and mechanical properties of the casting and will contribute to the ability of the casting to resist heat and/or corrosion.
Stainless steel has a minimum chromium content of 10.5%, making it more resistant to corrosive liquid environments and oxidation. However, this is not absolute. Stainless steel investment castings are "corrosion resistant" for service in liquid environments and steam below 1200°F (650°C) and "heat resistant" for service above this temperature.
There is a difference between wrought stainless steel and cast stainless steel. This is due to their chemical composition and microcrystalline structure, which is affected by how the material is produced, cast or extruded. These factors must be considered when selecting alloys for stainless steel cast metal projects.

Advantages of impeller stainless steel castings
Stainless steel impellers are made as "investment castings". These are made using a silica sol investment casting process which results in significantly improved surface and part quality compared to the more common die casting process or the sand casting process most commonly used for bronze casting. The end result is higher efficiency, impeller-to-impeller consistency, greater durability and more sustainable hydraulic performance.
Neither material is more likely than the other to form cracks or reduce expected service life when handled according to the manufacturer's instructions. However, the stainless steel material is generally stronger and may have a longer life expectancy in most cases.
Stainless steel offers improved surface properties that increase sustainable hydraulic performance and energy efficiency, increase chemical resistance/application flexibility, reduce the potential for corrosion or degradation, and reduce maintenance costs. There may be extreme applications where the chemical concentration is very high and stainless steel is not suitable, but so far, we have not seen an application where the pump can be applied.