The invention relates to a registration and alignment-based lineation-free
forging-
casting part
machining positioning method. Since an
aviation forging-
casting part is complex in structure, smaller in
machining margin and poor in blank consistency, if a traditional mode in which lineation is adopt to find
machining references is used, problems such as poor positioning accuracy, low alignment efficiency and high
rejection rate can be brought about, and those problems are the
bottleneck of the machining of
forging-
casting piece blanks, and seriously hinder the intelligent, automated and
numerical control development of the machining
modes of forging-casting pieces. In order to solve the above problems, a measurement coordinate
system and a machining coordinate
system are unified; registration and alignment are performed on the digital model of the blanks and the CAD model of the blanks under residual constraint; a
cutter location file is corrected through using a registration and alignment result; machining references can be determined accurately and automatically; after the accurate references are prepared, a lineation alignment auxiliary preparation process at a later stage is not required, and the prepared accurate references can be directly utilized to carry out quick and accurate positioning; and therefore, the
automation degree and
numerical control rate of the machining of the forging-casting piece blanks can be improved.