The invention discloses a taper sleeve type 
grinding device for 
machining an inverted cone sealing ring. The device comprises a group including an outer sleeve structure and an inner 
insertion structure, wherein the outer sleeve structure and the inner insert structure can be connected and fastened to each other through a connecting structure in a way that the opposite ends of the outer sleeve structure and the inner insert structure are matched in a socket way along the axial direction; the socket matching parts of the outer sleeve structure and the inner insert structure are rotation matching surfaces including an inner concave conical hole surface and an outer convex 
frustum surface; each rotation matching surface takes a central axis as a rotation center; the inner concave conical hole surface is provided with a taper angle beta 1; the outer convex 
frustum surface is provided with a taper angle beta 2; the taper angle beta 1 of the rotation surface of the outer sleeve structure is more than or equal to the taper angle beta 2 of the rotation surface of the inner 
insertion structure; the other end surface, in the backward direction of the socket end, of the outer sleeve structure is a 
reference surface; an axial internal concave structure of a cylindrical internal hole surface is arranged in the inner 
insertion structure; the cylindrical internal hole surface also takes an axis as a rotation center; and the internal 
diameter of the cylindrical internal hole surface is adaptive to the outer 
diameter of the machined sealing ring. The 
grinding device can be used to conveniently and accurately 
machine a sealing surface on a sealing end surface, wherein the taper angle is only about a few minutes or tens of minutes, the maximal 
cut amount along the axial direction is only tens of micrometers, the requirement on the surface quality of the sealing end surface is very high, and especially the sealing surface has an inverted cone surface.