EE WAS REMOVING A BAD TUBE FROM 2E FILTER. THERE WAS A BROKEN PUSHING LUG AND PART OF THE FIRST SECTOR NIPPLE. HE INSTALLED A PORTA-POWER HEAD BETWEEN WEST WALL OF FILTER AND THE REAMINING FIR ST NIPPLE. HE APPLIED PRESSURE TO THE HEAD AND STARTED TO TAP ON THE OPPOSITE END OF THE TUBEW WITH A 6# HAMMER TO TRY AND LOOSEN IT UP. AFTER THE THIRD HIT, THE REST OF THE NIPPLE BROKE OFF