Cross Head

A crosshead is a machine element used in slider–crank and similar mechanisms to guide the reciprocating motion of a piston rod and to transmit force between the connecting rod and the slider. It is placed between the piston rod and the connecting rod and moves back and forth along accurately machined guideways. The primary function of the crosshead is to eliminate the side thrust on the piston by taking the lateral forces produced by the angularity of the connecting rod. These side forces are absorbed by the crosshead guides, ensuring smooth linear motion of the piston rod and reducing wear on the cylinder walls. Crossheads are commonly used in steam engines, reciprocating compressors, and large internal combustion engines where heavy loads and long strokes are involved.