Replacing a Steel Overflow Launder with FRP

What can you do when acid is continually eating through stainless steel?

Project Details

  • INDUSTRY: Metals
  • LOCATION: North Carolina
  • YEAR: 2023
  • FOR MORE INFORMATION: Reference job C23-007


This tanks contents are so acidic that it eats through the stainless steel overflow launders very quickly.  Rather than continuing to replace it with steel time after time, the customer worked with us to develop an FRP solution instead.  We fabricated this new launder in our shop and then came onsite to install it in sections with crane assistance.  We mechanically fastened them to the tank and then laminated the sections together with a structural laminate and corrosion liner.

Steel vs FRP

Fabrication Process

  • We began by designing molds in our shop based on prints supplied by the customer. We then applied materials per the specifications on the prints to meet material thicknesses. 
  • Next, we fabricated the launder in the shop using Derakane 411 vinyl ester resin and Owens Corning Chopped Strand Mat.
  • We then separated the launder into six sections to be able to transport it to the customer’s facility.
  • Lastly, a protective topcoat, Ceilcote Flakeline 242, was applied. 


Instead of fabricating a separate teeth piece and mechanically fastening to the launders,  the teeth were integrated into the launder to reduce failure points.


Installation Process

  • Once the launder pieces were transported to the customer’s facility, the sections were crane into place individually.
  • Stainless steel anchors were used to support the troughs into place.
  • The joints were laminated together to form the full ring.
  • We then fabricated and installed supports underneath the launders, as well as a drain box to the existing piping.
  • Lastly, we applied a protective topcoat recommended by Blome International.


Replacing a Steel Overflow Launder with FRP