Abstract: Infeed grinding using a rotary table and a cup wheel is proposed to process the conical surfaces of the hydrostatic mechanical seal rings used in reactor coolant pumps. The substantial influence of the wheel radius, the distance between the rotary table and the wheel, the wheel pitch angle and the wheel roll angle on the theoretical radial profile error of the generated conical surface is analyzed thoroughly and comprehensively. A strategy for the implementation of ultra precision grinding of the conical surfaces of the hydrostatic mechanical seal rings used in reactor coolant pumps based on the minimum radial profile error and the minimum grinding contact length is determined. A hydrostatic mechanical seal ring sample made of silicon carbide that can be used in reactor coolant pumps is machined with very high form accuracy and very low surface roughness on an infeed grinding machine using a rotary table and a cup wheel. The circumferential run out, the radial profile error and the surface roughness Ra of the ground silicon carbide ring are measured to be 0.16 m, 0.15 m and 3 nm respectively.

Key words: Conical surface, Form accuracy, Reactor coolant pump, Seal ring, Ultra-precision grinding