Why is the material of the seawater pump chosen that way?
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The main concern is corrosion caused by seawater; what materials are generally used for seawater pumps?
Impeller: Tin bronze (various grades), such as ZCuSn3Zn8Pb6Ni1. Pump casing: Tin bronze (various grades can be used for casting), such as ZCuSn3Zn8Pb6Ni1. Pump shaft: Stainless steel 316L. Filter screen: 316L. Connecting bolt: 316. Outlet flange: 316; Upper and lower motor bearing housings: 316. Middle part: 316. Motor shaft: 316; Motor seal: rubber sealing O-ring ； Mechanical seal. The rubber material used for the motor expansion adjustment bladder.
The plastic is made of ultra-high molecular weight polyethylene, while the metal is made of 316 material
Worried that the 316 material is not sufficient, as chloride corrosion is too severe
So, using 316L material should be more than sufficient, I think
Ultra-high molecular weight polyethylene can be used; this material is resistant to corrosion and wear. However, it is not suitable for use when the medium temperature is above 100 degrees or in highly oxidizing environments. Our company uses this material to make pumps.
There are many CI roots in seawater. It corrodes relatively quickly in stainless steel; it is recommended to use pumps made of non-metallic materials such as engineering plastics.
It’s just seawater, so there’s no need to worry too much; the chloride content isn’t very high. If you’re still concerned, use 316L material with a low carbon content. What are the parameters regarding flow rate, head, and temperature? Using non-metallic materials is more cost-effective.
Use a magnetic pump, but add a filter for filtration
Generally, the impellers and pump casings are made of tin bronze, the pump shaft is made of 316L, while other components can be made of 316 stainless steel.
Fiberglass can be used; brands such as Meibo from the United States and Aeger from Italy are available, specifically designed for seawater transportation!