FOCUS ON TECHNOLOGY
Metal Alloy Upgrade in Corroding Process Vessels Marina Silva IGS Integrated Global Services Inc., Richmond - United States
marina.silva@integratedglobal.com
During a routine inspection in a US refinery a corrosion problem with
of the shell. These coatings needed to be applied repeatedly every 4-5
the second stage desalter and the overhead accumulator vessels had
years. In 2014, the inspection revealed areas where both the historical
been detected. The initial intervention with a nickel-copper thermal
nickel-copper thermal spray (TS) coating and organic patch repairs
spray coating did not appear to be a lasting solution. In 2017, refinery’s
have worn away completely, leading to deep pitting and metal wastage
engineers decided they needed a more permanent solution: High Velocity
beyond existing corrosion allowance.
Thermal Spray (HVTS) coating by IGS.
Moreover, when weld repairs were attempted adjacent to the failing
Introduction A US refinery identified a problem with its second stage desalter and
TS, a crack had formed on its heat affected zone (Fig. 2). In 2017, refinery’s engineers decided they needed a more permanent solution.
their overhead accumulator vessels during a routine inspection.
Evaluation
A nickel-copper thermal spray coating had been applied in both
IGS inspected the vessels and proposed a High Velocity Thermal
of these vessels approximately 20 years ago. Initially, the coating
Spray (HVTS) cladding solution to stop corrosion for the expected life
performed as expected, however after some time, localized damage
of the asset without any further maintenance anticipated for at least
was evident on the bottom third of both vessels (Figs. 1A - 1B). Initially,
the next 15+ years. HVTS technology utilizes next generation alloy
various organic coatings were chosen for patch repairs to the bottom
materials, which offer erosion-corrosion protection, even in HT/HP
20
N.32 - 2019 DECEMBER - ipcm® Protective Coatings