OVERVIEW: The 8 year old pump had dropped off in efficiency due to the combination of corrosion erosion and mechanical fatigue. This was due to a poorly specified and applied coating which was delaminating allowing corrosion to exist.
INDUSTRY
ENVIRONMENT
River Water
SUBSTRATE
Cast iron body
CHALLENGE
The pump had dropped off in efficiency due to the combination of corrosion erosion and mechanical fatigue. This was due to a poorly specified and applied coating which was delaminating allowing corrosion to exist.
SOLUTION
After 8 years in service the substrate was corroded and heavily contaminated with metallic salts. Treatment using a combination of methods including abrasive blasting, hot washing and acid washing to reduce salts below 25ppm. We then recommended the application of 2 coats of Chem-tect™ RB 364; a glass flake filled vinyl ester providing an excellent corrosion barrier and long term protection. We then applied 2 coats of Epo-chem™ RP 500 to enhance fluid efficiency in turn reducing power consumption.
SCOPE
Strip and assess
Manufacture template to ensure mating faces match
Grind chamfer on all flanged faces, allowing the coating to be applied on the flange face preventing future crevice corrosion.
Protect critical dimensions
Abrasive blast and treat to reduce metallic salts by hot washing and re-abrasive blast.
Apply corrosion barrier Chem-tect™ RB 364
QA included spark testing and DFT
Apply topcoat of Epo-chem™ RP 500
PRODUCTS
OUTCOME
By coating with Chem-tect™ RB 300 & Epo-chem™ RP 500, future corrosion erosion is prevented with a reduced amount of friction through composite technology. The pump now functions more efficiently when in use consuming less power, which led to carbon credits and a reduction of greenhouse gas emissions. The payback period of the entire refurbishment worked out to be only 14 months.
RELATED CASE STUDIES
Air Receiver Restoration for Long-Term Durability
Pitting corrosion near shaft landing After first abrasive blasting After 2nd Abrasive blast holes were found requiring composite reinforcement Filling void in difficult to reach
High Performing Replacement for 316L SS
On inspection flange corrosion Deep pitting on forged section Application of 1st coat Ready to be put into service for 25+ years of life OVERVIEW:
Power Station Debris Filter Lining Repair
Damage to existing rubber lining Internal void to be filled in around the circumference of the screen Close up of repair area for the full