Abstract: This study compared the nitriding layer properties of 38CrMoAl material under different base hardness and surface conditions, and studied the final nitriding layer properties and dimensional accuracy of the rotor seal structure's rotor ring parts using different processing technology methods. The results show that by controlling the base hardness of the rotor ring parts at 28-32HRC and not phosphating the nitriding surface, the excellent nitriding layer properties can be obtained. For the rotor ring parts, by taking the processing method of first nitriding, then grinding, and finally performing secondary nitriding treatment or taking the processing method of first grinding and leaving a 0.05mm machining allowance for subsequent nitriding treatment, the final rotor ring parts can have excellent nitriding layer properties and meet the high dimensional accuracy requirements.