This back and forth motion would cause the hole made by the cutting head to be more open in a particular direction and therefore facilitate steering of the drilling pipe in that direction underground.
North Bay Plastic Molders produces plastic caps for a variety of applications, including specialized shipping caps for pipes, thread protectors for protecting the threads of drilling pipes and end caps for explosives, and plastic electronics housings.
The oil company notified state officials and eventually submitted a sample of "scale," the crusty and potentially occluding mineral deposit that forms along the interior of drilling pipes.