Closure head lifting device for a nuclear reactor

A lifting device for lifting a closure head assembly from a reactor vessel body in a nuclear power generation system, the lifting device comprising at least one lifting element having an engagement surface configured to engage an underside surface of the closure head assembly, the at least one lifting element being axially adjustable in height between a retracted position in which its axial height is such that the closure head assembly seals against the body of the reactor vessel and an extended position in which its axial height is such that the closure head assembly is raised above the body of the reactor vessel;

• wherein the lifting device has a center of mass which is vertically lower than the center of mass of the closure head assembly.