Heads/End Closures

Heads/End Closures are hemispherical, elliptical, or dished components that form the sealed ends of cylindrical steam generator vessels in industrial applications. They are engineered to withstand internal pressures up to 2500 psi (17.2 MPa) and temperatures exceeding 600°F (315°C), distributing stress uniformly to prevent deformation or failure. These closures incorporate flanged connections for piping, inspection ports, and safety devices, and are designed with specific geometries (e.g., 2:1 elliptical heads) to optimize pressure resistance and minimize material usage while complying with ASME Boiler and Pressure Vessel Code standards.

Heads/End Closures operate by converting internal pressure loads into membrane stresses that are evenly distributed across their curved surfaces, reducing stress concentrations compared to flat plates. The curvature (e.g., knuckle radius in torispherical heads) allows for elastic deformation under pressure, maintaining seal integrity via gaskets and bolted flanges. In steam generators, they facilitate thermal expansion and contraction cycles without leakage, supporting functions like steam separation or feedwater entry, and are often insulated to minimize heat loss.