My country's existing head standards are formulated separately based on different structural types (elliptical, dished, conical) and forming methods (stamping, spinning). This not only results in inconsistent quality requirements for heads from different standards, but also creates difficulties in the selection of standard heads and the revision of standards.
Previous head standards were only compatible with GB150 "Steel Pressure Vessels," meaning they only considered the manufacturing, inspection, and acceptance requirements of heads designed according to the rules. However, my country completed a dual-track system of basic pressure vessel standards (GB150 and JB4732, along with the "Analysis and Design Standard for Steel Pressure Vessels") as early as 1995. The lack of head standards mating with analysis and design is a significant shortcoming in my country's pressure vessel standardization work.
GB150 is a mandatory standard, but the head standards compiled based on and mating with GB150 are only guidance (recommendation). This is clearly unreasonable and makes it difficult to guarantee the quality of this important pressure-bearing component.