Method and apparatus for adjusting impeller-sealing ring clearance in a pump

A pump arrangement is provided having a seal ring configured with at least three left-handed threaded apertures; a suction half casing; a suction liner configured between the seal ring and the suction half casing; and at least three adjusting screws, each adjusting screw having a first end portion, a second end portion, a third intermediate raised portion between the first end portion and the second end portion, and a fourth portion configured to allow each adjusting screw to be rotated clockwise or counterclockwise. Each first end portion is configured to pass through a respective aperture of the suction liner and configured with corresponding left-handed threads that couple to a respective left-handed aperture of the seal ring. Each second portion is configured to pass through a respective aperture of the suction half casing to allow the fourth portion to be accessed to allow each adjusting screw to be rotated clockwise or counterclockwise. Each adjusting screw is configured to be rotated clockwise and moved axially until the third intermediate raised portion pushes against the suction half casing, causing the adjusting screw to stop moving axially and the seal ring to move away from the suction liner and towards the impeller as the adjusting screw continues to be rotated clockwise, or each adjusting screw configured to be rotated counterclockwise and moved axially until the third intermediate raised portion of the adjusting screw pushes against the suction liner, causing the adjusting screw to stop moving axially and the seal ring to move towards the suction liner and away from the impeller as the adjusting screw continues to be rotated counterclockwise.