Fault Phenomenon: SANY SR235 rotary drilling rig a periodic “clunking” sound occurs during rotary head swing.

Troubleshooting Process:
– Checked balls: swing bearing balls shattered.
– Checked raceway: raceway surface spalling.
– Checked lubrication: long-term lack of grease.
– Checked bolts: mounting bolts loose.

Root Cause: The rotary head swing bearing lacked lubrication for a long time, causing dry wear between balls and raceway, eventually leading to breakage.

Required Parts: Replace rotary head swing bearing assembly.