As one kind of jacketed vessels, half-pipe jacketed vessels are widely used in engineering owing to the structural and heat transfer advantages. But for the design of half-pipe jacketed vessels, there are limitations in codes ASME VIII-1 and ASME VIII-2. In this paper, a new design method based on numerical limit-load analysis is proposed to design half-pipe jacketed vessels. The scheme and advantages of the method are presented through a design of half-pipe jacketed vessel. It is found that by performing limit-load analysis, problems of the codes ASME VIII-1 and ASME VIII-2 about the structural limitation of the half-pipe jacketed vessels and loading limitation are solved. In addition, by performing limit-load and parametric analysis, the strength weakness areas on the vessels can be found, and the rational strength design of a structure can be achieved.