Sandvik 152 519 68 Shank Bushing

The shank bushing, part 152 519 68, is judged by the gap it leaves around the shank, because that gap decides how straight the shank sits when the piston strikes it. As the bore wears oversize the shank is free to tilt a little, the blow lands slightly off the axis, and the extra side force is passed on to the seals and guides behind it, which then fail earlier than they should.

The bore diameter should be measured against the service limit and not judged by eye, since a bushing with an even-looking bore can already be well past tolerance. Lubrication at this location is also critical, because it is the sliding contact between a hard rotating shank and the bushing that wears the bore, and a lack of lubricant or contaminated oil speeds that wear considerably. Replacing the bushing by its exact reference restores the original bore and keeps the shank aligned with the piston. Stalroc quotes this Sandvik reference by part number and exports worldwide to mining, quarrying, and drilling contractors.