The Challenge

A nitrogen facility encountered recurring issues with corrosion of flange faces due to chemical exposure and pressure conditions . Upon disassembling the flanges , the maintenance personnel observed significant pitting on the raised face portions of the thermowell flange connections .

Initially , a spiral wound gasket was used in the application , but concerns arose regarding the long-term compatibility of this gasket type with the facility ’ s nitrogen-based processes .

Problem Identification

The original spiral wound gasket was found to be insufficient for use in the nitrogen processing system . While the gasket winding sealed sufficiently to prevent a leak , the metal inner ring left a small void near the inside diameter

of the flange exposed to the media . This unsealed area allowed the media to accumulate on the flange face . The stagnant media began pitting the faces of the flange , causing corrosion between the flange bore and the inside diameter of the gasket winding .

The facility management , therefore , grew concerned that the corroded flanges could lead to compromised sealing performance . Upon inspection , the corrosion was deemed severe enough that maintenance personnel decided to replace the entire flange to prevent

Cross-section of a dual gasket system with an outer ring .

potential leaks . As replacing flanges is costly and time-consuming , the facility required a solution that could seal

directly at the bore of the flange and increase the long-term reliability and safety of the process .

Solution Driven Approach

The manufacturer ’ s engineering team conducted a comprehensive root-cause analysis to understand the full extent of the issue . Based on the findings , it was determined that a unique dual-sealing system would provide a more robust solution . This approach involved replacing the original spiral-wound gasket with a double-rail camprofile gasket . To prevent media buildup at the bore of the flange , a layer of compressible mechanical packing ( Teadit 2202 ) was also installed .

1 . Dual Sealing System : The manufacturer ’ s gasket design consisted of a 321ss core manufactured with two serrated , concentric sealing rings . This construction allowed for reli-