OVERVIEW: Chemcote’s specialist team has achieved excellent corrosion protection for their customer. By using Chem-tect™ RB 300 the Open Top Quench Tank is expected to surpass a further 20 years life in service.
INDUSTRY
ENVIRONMENT
Mildly acidic water ranging between 50-70°C
SUBSTRATE
30 Year Old Heavily Pitted Steel
CHALLENGE
It was too late for some areas requiring replacement and repair of wall plate and internal pedestals supporting the rolls requiring replacement. Removal of the tank wasn’t feasible and an insitu cost effective repair method was required. With live crane rails, great heights and the centre of an active production area to contend with Chemcote came to the rescue.
SOLUTION
Prefabricated items to be coated before installation to reduce application time on site to particularly on difficult to reach areas
SCOPE
Removal of heavy corrosion and scale by needle gunning, scabbling and chiselling exposed the condition of the substrate beneath all of the scale and build up, locating holes through the plate and very thin areas requiring unplanned fabrication repairs. New supports and a weir plate were welded into place, in addition to penetrated weld seams allowing moisture to permeate. Abrasive blast was carried out to class 2.5
Composite repair techniques and pit filling were used to achieve structural integrity on damaged areas
Application of RB300 Series to a nominal thickness of 1,000µm total DFT
Holiday testing at 12kV was carried out
PRODUCTS
Chem-tect™ RB 300 Series, a glass flake filled vinyl-ester
OUTCOME
By coating with Chem-tect™ RB 300 will provide an excellent corrosion barrier, expected to exceed 20 years life in service
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