HRSGs and power boilers are built by assembling large numbers of components, mostly by welding. Design choices in optimizing heat transfer against overall cost lead to configurations that aim to minimize the number of welds per square meter of heat transfer surface. In addition, fabrication of the modules is frequently subcontracted by the OEM for manufacture in regions where manpower is cheaper. The OEM becomes in effect an integrator of components built by others. How can Product Quality for pressure parts be assured in that context?

Thermohydraulic simulations can provide detailed heat recovery steam generator (HRSG) data to help determine the root cause of failures, predict the degree of wear from various mechanisms, and assess the overall thermal efficiency of the boilers. In this article, the results obtained from three case studies are presented to show the real-world benefits obtained through thermodynamic simulations.

Many combined cycle power plants have experienced thermal shock damage to bypass power piping, especially in the HP steam and Hot Reheat systems.

Since 2007 the ASME B31.1 Power Piping Code has included Chapter VII, establishing mandatory requirements for Operation and Maintenance. The key elements of this program are discussed here, and require that Operators outline a detailed maintenance plan for their Covered Piping Systems (CPSs). The Code also requires that operators perform regular Condition Assessments of their CPS ensuring that relevant degradation mechanisms are being covered.