Removal tool for removing a thrust socket of a pumping injector and tool kit incorporating such removal tool

Removal tool (10, Figure 3) for removing a thrust socket of a pumping injector, the thrust socket being received in and attached to a retainer cup through a coiled flat annular spring ring 4 received in an annular groove 5 of an inner wall of the retainer cup. The removal tool comprises a holding shaft 11 having a spring ring removal device (12, Figure 3) at a first end (11a, Figure 3), and a stem 13 with a hook 14 at a distal end for catching the spring ring 4. The removal device is sized to pass through a tubular gap (6, Figure 3) between a head (2a, Figure 3) of the thrust socket and a tubular wall 3b of the retainer cup, such that it can rotate about the axial direction when inserted between the head and the wall with the axial direction parallel to the main axis (A, Figure 2) of the thrust socket.