An extremely large main cooling water pump casing and cover – weighing in at around 16 tons – was delivered to Corroserve’s Leeds workshop for a full inspection, refurbishment and protective coating after 20 years of uninterrupted service in the power generation sector.
During inspection it was discovered that apart from corrosion, the split mating flanges had also warped. As a first step Corroserve’s workshop team abrasive blast cleaned the internals of the pump to ISO8501-1 Sa2½ to remove corrosion
and any existing coating. This provided a surface profile of 50μm. Multiple coats of Corroglass 600 series were then hand applied to the casing and cover to achieve a minimum dft of 1500μm. The flanges were then cast in using the same material and dressed off.
Not only is Corroserve’s workshop equipped with a large capacity blast cleaning booth capable of handling extremely rePAIr outweIGHs rePLACeMent large workpieces, it also has overhead cranes which can lift up to 20 tons, so size was never an issue.
To finish the refurbishment, the external surfaces of the pump were also blast cleaned to Sa2½ and two coats of Plasmet ZF coating applied. The coating was spark tested to ensure no holidays were present and to reinforce the quality of the work done.
The professional preparation of all parts before coating and the use of Corroglass 600 will ensure that the pump will be in service for another 20 years.