Improved wear bushing install and retrieve system for a petroleum well, and Method therefor

The invention is a petroleum well wear bushing install and retrieve system comprising - a wear bushing (1), - for being arranged in a wellhead (4), and - being of large bore for a drill pipe string (O, OL, OU) carrying a drill bit or other well tool below to pass through it, and - said wear bushing (1) provided with two or more internal, upward-closingJ-slots (10) with upward bottoms (11), - a running tool (2), - said running tool arranged for being run as part of said drill pipe string (0, 0U, 0L) at least extending above said running tool (2) and having a through-bore tool mandrel (20), - said running tool having radially extending ribs (22) with an outer diameter allowing to pass said J-slots, characterized in that said ribs (22) having radially extending spring-loaded dogs (21) arranged for controlled engagement with said internal J-slots (10), - each said radial dogs (21) having an upward directed key profile (210) for engaging with a corresponding lock profile (110) in said upward bottom (11), - shear pins (3) arranged for initially, for running in said wear bushing (1) to said wellhead (4), said shear pins (3) connecting said radial ribs (21) to said wear bushing (1); so as for allowing running in said wear bushing (1) on said running tool (2) and inserting it in said wellhead (4), and for then putting weight on said drill pipe string (0U) to shear out said shear pins (3) and pass said running tool (2) further downwardly for further operations below said wear bushing (1) or retrieving said running tool (2) upwardly.