SEAL BUSHING NUT

812 728 59 SEAL BUSHING NUT Installed in high-load pivot points, such as those found in the boom and feed systems, this bushing acts as a sacrificial bearing between a steel pin and its housing. It absorbs the immense radial and axial forces generated during drilling and tramming. This function allows for smooth articulation and prevents direct, damaging metal-on-metal contact with more expensive structural parts.

As the bushing wears from normal use, clearances in the joint increase, leading to unwanted play or 'slop'. This directly impacts drilling performance by making it difficult to accurately position and collar a hole. The resulting vibrations also transfer extra stress to welds, cylinders, and hoses, which can accelerate fatigue and cause other failures.

Proper and frequent greasing is the most effective way to extend the life of any bushing. During inspections, check for excessive movement in the joints. If a pin moves noticeably inside its bore before the entire linkage moves, the bushing is worn and should be replaced promptly, ideally along with the pin, to restore the joint's original tolerances.