Careers In late 2025, IGS inspected the caustic wash settler and confirmed that the HVTS applied in 2020 remained in excellent condition, continuing to protect the internal vessel pressure boundary with no signs of degradation. As a proactive measure, HVTS was re applied to approximately 5 square meters of stripped areas on the baffle plate weld seams and a section of the picket fence area to restore full integrity following mechanical repair work.
Caustic Vessel Protected After Repeated Failures
Plant and Challenge Description
A major petrochemical facility operating a caustic wash settler experienced persistent internal degradation due to an aggressive caustic service environment. The settler is critical to the demercaptanization process and was originally installed in 2011. After extensive internal damage occurred, the vessel was replaced in 2015, and an organic lining was applied across the full internal surface area of 351 square meters. The organic coating failed under repeated exposure to caustic conditions, resulting in caustic stress corrosion cracking, which manifested as pitting and cracking of welds. The objective was to establish a long term internal barrier to maintain the shell integrity for the design life of the vessel.
Moving Beyond Coatings to Lasting Protection
The plant had previously attempted to mitigate corrosion using organic linings, but these solutions failed prematurely under operating conditions. Other traditional repair options, such as vessel replacement or welding based methods, would have introduced heat related stress and resulted in extended downtime. Instead, the team selected IGS due to its proven track record with HVTS cladding in caustic environments, rapid deployment capabilities, and zero heat input. IGS’s consistent performance in delivery and asset protection made it the strategic choice for this high risk asset.
IGS Solution Delivery
IGS mobilized to site and removed the failed organic lining. HVTS high velocity thermal spray alloy cladding was then applied to the entire vessel shell. In addition, 20 small bore nozzles were fitted with customized nozzle inserts to eliminate localized corrosion risk. The selected HVTS alloy was specifically engineered to resist caustic stress corrosion cracking, pitting, and hydrogen embrittlement, which are all known corrosion mechanisms in this environment. Cladding thickness measurements were taken throughout the application and compiled into a full asset condition map to document application quality and establish a baseline for future inspections.
Quantifiable Impact and Proven Results
The IGS HVTS cladding solution provided a robust corrosion resistant alloy barrier that has remained in excellent condition after more than five years of continuous service.
2025 Inspection
Moving Beyond Coatings to Lasting Protection
The IGS HVTS cladding solution provided a robust corrosion-resistant alloy barrier that remains in excellent condition after more than five years in continuous service.
“HVTS cladding is widely recognized for its performance in sour acidic service, but its capability in caustic environments is less well known. This project, together with prior experience, demonstrates that HVTS continues to build a strong track record of proven performance in both highly acidic and caustic services, delivering durable, fit for service protection where other solutions have failed.”
– Dennis Snijders, Senior Director – Middle East, IGS
Free consultation with an IGS Subject Matter Expert
IGS is here to provide information, answer questions and create an effective solution for your needs.