The invention relates to a manufacturing method of a double-chamber kiln, in particular to a manufacturing method of a double-chamber lime kiln nonstandard ash discharge system. The manufacturing method of the double-chamber lime kiln nonstandard ash discharge system comprises the following steps: a manufacturing process and a scheme are formulated according to design drawing requirements and manufacturing standards; a bottom panel typesetting picture of an ash discharge system is drawn to obtain reasonable wide plate ordering sizes and to customize proper materials; a bottom panel of the ashdischarge system after typesetting and blanking is fixed with a flange plate and an ash discharge panel by using a tool, and then, is drilled; a platform is firstly assembled and corrected, or the assembly and the spot welding are performed on a bottom frame on a corrected platform according to the drawing requirements, and then, the welding and the correction are performed; the corrected bottom frame and a bottom panel are assembled on the platform; the welding and the correction are performed; then, the flange plate and a thermal insulation ceramic fiber pad are installed; a bolt is used forfixing after covering an ash discharge panel; the flatness is detected; and then, sand blasting, painting, numbering and packing are performed. The manufacturing method of the double-chamber lime kiln nonstandard ash discharge system enables users to directly know difficulties and key control points during manufacturing, so that the manufacturing quality of the double-chamber lime kiln ash discharge system is guaranteed.