HRSG Expansion Joints
A Heat Recovery Steam Generator (HRSG) is an energy-recovery heat exchanger designed to recover waste heat from a hot flue gas that would typically be vented to the atmosphere and convert it to steam. HRSG expansion joints used in these applications can reach temperatures in access of 2500*F. As the exhaust gases are ducted away from their source to the steam generator, expansion joints are used to connect the equipment.
In power generation, gas turbines are used to turn electrical generators and the waste heat from the jet engine is ducted to a HRSG to generate steam that powers a secondary electrical generator (which is steam driven). In these plants, Zepco has designed and installed HRSG expansion joints on the combustion air inlet ducts to the combustion turbine, as well as the joints on the gas outlet to the HRSG and stack breeching. On the HRSG itself, we also build penetration seals, which are designed to seal the HRSG casing to any pipes that are penetrating through the casing.
The combustion air joints are typically molded rubber or Teflon and operate under 300*F. The exhaust gas penetration seals can see gas temperature up to 1200*F and are composite type joints.