Bare and limiter DEMO single module segment concept first Wall misalignment study by 3D field line tracing

•Engineering workflow for misalignment studies by using 3D field line tracing codes.•The heat load pattern on geometrical configurations deviating from their reference ones can be retrieved by using penalty factors.•Penalty factors are not self-exhaustive: heat flux magnitude and duration of its applications are parameters to consider in an engineering design.•During Normal Operations, hot spots should be prevented in case of segments’ misalignment by defining assembly tolerance levels.•Misalignment tolerance studies help drive the design of FW and limiters.