High precision cylinder helical compression spring squareness detecting method

The invention relates to a detecting method of a high-accuracy cylindrical helical compression spring, specifically to a method for detecting the verticality of the high-accuracy cylindrical helical compression spring. The detecting method improves quality detection standards of the verticality of the compression spring to the utmost extent, so that the detected compression spring can satisfy the operating requirements of various application situations. The detecting method comprises following detecting steps: in the state without loading, the detected compression spring is horizontally arranged in the horizontal V-shaped groove of the spring placing frame, one end face of the spring reclines against a wide seating square, the spring is turned around one circle, and meanwhile a feeler gauge is used to detect the distance between the end face of the spring and the wide seating square, and then the maximum value is taken as the vertical deviation of the end face of the spring; the spring is overturned, the vert