Semi-automatic pipe threading plant and apparatus therefor

A semi-automated plant for threading pipe, said plant comprising a building, first conveyor means for receiving outside of said building pipe to be threaded, aligning said pipe and conveying said pipe to inside said building, with said pipe entering said building at a side thereof, with the axial length of the pipe generally parallel to that building side and at least one end of said pipe aligned with respect to a point on that building side, a first threading means for threading the exterior of a first end of said pipe at a location higher than the height of the first conveyor means at said building side, first pneumatic lift means for lifting said pipe from said first conveyor to the general level of said first threading means, first hydraulic lift means cooperating with said first pneumatic lift means for fine adjustment of the height to which said pipe is lifted so that said pipe is at the proper height for said first threading means, first three roll clamp means for clamping said pipe in position to be threaded by the use of three rollers, while permitting said pipe to rotate in said first threading means, bucking means for applying a coupling to the threaded first end of said pipe, second conveyor means for conveying said pipe from said first threading means to the vicinity of said bucking means, second lift means for lifting said pipe from said second conveyor means to the proper height for said coupling to be applied, second threading means for threading the exterior of the second end of said pipe, third conveyor means for conveying said pipe from said bucking means to the vicinity of said second threading means, said second threading means at a location higher than the height of said third conveyor means, second pneumatic lift means for lifting said pipe from said third conveyor means to the general level of said second threading means, second hydraulic lift means cooperating with said second pneumatic lift means for fine adjustment of the height to which said pipe is lifted so that said pipe is at the proper height for said second threading means, second three roll clamp means for clamping said pipe in position to be threaded by the use of three rollers, while permitting said pipe to rotate in said second threading means, and fourth conveyor means for conveying said pipe with each end threaded and at least one coupling thereon away from said second threading means and out of said building, with the pipe being maintained while in said plant generally parallel to said side of said building.