Rally discussed the unit heat exchangers with the Client to fully understand their previous issues and explore potential alterations. The team decided that converting the closure to a Kammprofile gasket-type design was the best way to eliminate the problematic diaphragm seal.
Rally worked with the Client’s preferred supplier to ensure that the new channel / bundle assembly would be 100% compatible with the existing exchanger shell, and fully compliant with modern pressure equipment codes.
3D modeling helped the team to visualize construction work, minimizing the removal of adjacent piping and structures.
The team initially planned to upgrade the new bundle to Alloy 825 tubing for improved corrosion resistance. However, a late switch back to SA-179 carbon steel tubes became necessary due to unforeseen supply chain issues.
A material requisition was developed for a new tube bundle and channel assembly; it contained all the specifications for design, metallurgy, fabrication, and shop inspection.
A multi-discipline CWP was issued with detailed instructions for safely extracting the existing channel / bundle assembly and welding the new one into place.
Rally arranged for the new Kammprofile gasketed channel cover to be installed and pre-tensioned prior to shipping. This saved the Client valuable time during the plant turnaround.