This unique thread machining technique is normally found in transfer lines, where two dedicated dual-axes CNC pipe end finisher machines are used, one for each tube end-side.
Three rotating auto-centering jaws, equally divided by 120° and hydraulically actuated, carry exchangeable carbide toolholders. A set of 3 carbide inserts is required to perform the full thread profile in one single pass.
Suitable for both buttress and round API thread profiles, each multi-tooth threading insert performs a different application.
The first insert that contacts the materials performs the rough operation, the middle one the semi-finish operation and the third and last one the finish operation. The machine setup and accuracy is extremely important in order to achieve the required thread accuracy and best quality.
At the end of the threading process, the jaws open and rotating spindle housing retracts to original position.
Insert size:
Length: 15.875 mm (5/8”), height: 15.875 mm (5/8”) and thickness: 4.76 mm (3/16”). In addition, they usually have an internal coolant hole.
Each cutting tool features a seat, threading insert and chipbreaker. They are all made of carbide and usually coated.