Inplace ball valve repair apparatus

Claim 1

Apparatus for inplace refinishing of the annular seating surfaces in top loaded ball valves, said seating surfaces having a desired orientation such that the seating surfaces are inclined inwardly and downwardly at a specified very small angle with respect to a plane normal to the horizontal top surface of the valve's housing and lines in the planes defined by the seating surfaces and parallel to the top surface are parallel, which comprises: (a) a locating ring having a bottom surface adapted for resting on the top surface of the valve housing, the top surface of said locating ring providing a flat surface oriented similarly relative to the desired orientation of each seating surface of said valve, the centerline of said locating ring being oriented parallel to the desired orientation of the seating surfaces and over the centerline of said valve when said locating ring is aligned on said valve housing, said locating ring having a first pair of apertures positioned on a first side of the centerline and symmetrically disposed relative to said centerline, said locating ring having a second pair of apertures positioned on the second side of the centerline and symmetrically disposed relative to said centerline in the same way that said first pair of apertures are symmetrically disposed; (b) an alignment gage for positioning said locating ring on the top surface of said valve, said alignment gage including a first plate which is disposed on the top surface of the locating ring, said first plate including a pair of dowel pins disposed to mate with either of said first pair of apertures or said second pair of apertures of said locating ring so that the position of said first plate is precisely fixed on said locating ring, said alignment gage having a second plate which is attached to the first plate and extends downward into the central chamber of the valve when the gage is positioned on the locating ring, said second plate having a pair of measuring gages secured thereto, each gage having a measuring tip and an indicator, said measuring gages being oriented so that the measuring tip of each gage is perpendicular to the centerline of said locating ring when said alignment gage is positioned on the locating ring, the measuring tips of said measuring gages being separated so that the tips are aligned with the sealing surface on opposite sides of the inlet passage of the valve when facing the sealing surfaces, said first plate having openings for viewing the measuring tips and indicators of said measuring gage when said alignment gage is disposed on said locating ring; (c) a carriage plate having a bottom surface adapted to rest on the top surface of said locating ring, said carriage plate having a pair of dowel pins disposed to mate with either said first pair of apertures in said locating ring or said second pair of apertures in said locating ring, said carriage plate being disposed on said locating ring after said carriage plate being positioned on said valve through use of the alignment gage, said carriage plate having channel-forming means, the channels formed by said channel-forming means being parallel and inclined at said very small angle with respect to the bottom surface of said carriage plate; (d) a cutting tool having a housing adapted to be supported by said channels and slide in said channels, said cutting tool including a boring head disposed to face the sealing surface of said valve and having its cutting plane oriented normal to the channel formed by said channel-forming means, said cutting tool having means for driving said boring head; and (e) means for sliding said cutting tool in said channels to position said boring head relative to the valve face, said means for sliding including measuring means for indicating the position of the cutting tool; (f) whereby, after said locating ring is accurately positioned with the air of said alignment gage, said alignment gage is removed from said locating ring and said carriage plate with said cutting tool thereon is inserted into said apertures in said locating ring.