These are fitted to crosshead engines and are vertical sliding bearings which locate and maintain alignment of the crosshead over the whole length of engine strokes.
They are subjected to fluctuating load from the transverse component of the connecting rod reaction.Guide bars or surfaces are secured to the frames adjacent to the unit and have either cast iron or Steel bearing surfaces.
Guide slippers (or shoes ) are attached to the end of crosshead and may be free to articulate; they are white metal lined with oil grooves lubricated from the crosshead.
Guide clearances for a larger engine should be inspected regularly and should not exceed 0.7 mm.
Excess clearance will result in noise, wear on bearings and glands, irregular loads and fatigue.