A washover pipe and mill, which are connected to the drill string, may be moved into contact with {HEAD ~ the object} after the mandrel is unlatched from {TAIL ~ the drill string} for milling through the object 
A washover pipe and mill , which are connected to the drill string , may be moved into contact with { HEAD ~ the object } after the mandrel is unlatched from { TAIL ~ the drill string } for milling through the object
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH