QKA-series CNC pipe thread lathes were developed mainly for the turning of oil-field pipe threads. But now they are also used to the turning of pipe threads of various kinds,e,g. cylindrical and conical threads, threads connected continuously one another, and end-face threads as well, and they can also be used as universal CNC lathes for the turning of circumgyration bodies of various curving generatrices. These machines are suitable for varified work-pieces machining in medium and small batches, and are for good flexibility, high efficiency, finishing up with good conformity, and are easy to program, simple to operate. So they are ideal medium-type mechanical machining equipment.