Through bolts (tie rods) secure the back head, main cylinder, and front head of a hydraulic rock breaker under intense pre-load tension. Bolt stretch, unequal torquing, or fatigue failure causes body gap oil leaks, cylinder warping, and piston seizure. This technical guide explains the root causes of through bolt failure—including blank firing and prying—and outlines essential diagonal torque protocols, cold-rolled thread advantages, and anti-seize lubrication practices to protect your power cell.
