This standard specifies the general requirements, inspection methods, quality grades and inspection reports for magnetic particle testing of valve pressure cast steel parts. This standard is applicable to the inspection, quality rating and acceptance of surface or near-surface defects of pressure magnetically conductive steel castings of valves (hereinafter referred to as steel castings). Magnetic particle testing of pressure cast steel parts such as flanges and pipe fittings matched with pipelines and non-pressure cast steel parts can also be performed with reference to this standard.