Katherine Hou
Shijiazhuang Naipu Pump Co., Ltd
Tel: +86-311-83802338 Fax: +86-311-87162902
Cellphone/ WeChat/ WhatsApp: +86-15028111051
The Corrosion Reason and Solution
1. Electrochemical corrosion:
The pump flow channel using same metal materail.
Small wearing parts as an anode made of low-potential metal. Large parts as the cathode made of high-potential metal.
2. Uniform corrosion:
Using suitable material(including non-metal). Consider sufficient corrosion allowance when designing the pump.
3. Intercrystalline corrosion:
Annealing treatment for stainless steel materail part. or using ultra-low carbon stainless steel.
4. Pitting corrosion:
Using Mo steel(usually 2.5%Mo). And Mo content should be increased accordingly while Cl content and temperature rise.
5. Crevice corrosion:
Using high content of Cr, Mo metal.
12% Cr steel <17% Cr steel <Austenitic SS
< Austenitic 316SS.
6. Stress corrosion:
High Ni content (Ni> 25%-30%) of austenitic Cr-Ni steel.
7. Erosion corrosion:
Ferrite Cr steel <austenite-ferritic steel> austenitic steel.
8. Cavitation corrosion:
Using cavitation resistant material. Such as Hard alloy, Phosphor bronze, Austenitic SS, 12% chrome steel. etc.
How to prevent corrosion problems in slurry pump?
1. Material selection:
Factory experience. Similar applications in other site. Experiecne of pump manufacturers. Appropriate documents etc.
2. Coating technology:
Widely used coating Fusion Bonded Epoxy (FBE) and Polytetrafluoroethylene (PTFE). The
effectiveness of the coating is dependents on the type of
coating, the preparation of the coating, the application of the coating,
the type of corrosion involved, and the type of liquid to which the
coating is exposed.
