BTA Drill Head Jamming: Causes and Recovery
BTA drill head jamming is one of the most difficult problems to recover from in deep hole drilling. The head binds in the bore, the spindle stops under overload, and the head cannot be retracted by normal means. I have dealt with this on holes from 20mm to 150mm diameter, and the recovery approach depends heavily on how badly the head is wedged. Problem Description A jam occurs when the drill head becomes mechanically locked inside the bore. The spindle torque spikes to 100% or more of the rated maximum, the machine triggers an overload alarm, and the head refuses to move in either direction. In severe cases, the drill tube twists visibly before the spindle stalls. ...