Abstract: A thread making device that has a thread form with controlled height adjustment. The thread making device is formed from a threading cartridge mounted on a threading bar. A thread form with a cutting edge is secured in a pocket on the threading cartridge bounded on one side by an adjustable height clamp, whose position relative to the threading cartridge is controlled by serrated faces on the adjustable height clamp and the threading cartridge. The thread form has a thickness extending in a wear direction, and the serrations of the serrated faces allow height adjustment of the adjustable height clamp in the wear direction.

Abstract: A pigging ball valve with a ball core mounted on an improved trunnion mounting. The pigging ball valve has a valve housing with a longitudinal axis. A side entry port on the valve housing is provided for entry of pigs into the valve housing. The ball core has an interior bore and is mounted on a trunnion in the valve housing for rotation about a transverse axis to the longitudinal axis of the ball core. The trunnion is a rotating stem journalled in the valve housing and connected to the ball core by a non-cylindrical portion and a cylindrical portion extending from the non-cylindrical portion towards the interior bore of the ball core. Preferably, the cylindrical portion terminates inwardly in a curved portion fitting the interior bore of the ball core.

Abstract: A pigging ball valve with a ball core mounted on an improved trunnion mounting. The pigging ball valve has a valve housing with a longitudinal axis. A side entry port on the valve housing is provided for entry of pigs into the valve housing. The ball core has an interior bore and is mounted on a trunnion in the valve housing for rotation about a transverse axis to the longitudinal axis of the ball core. The trunnion is a rotating stem journalled in the valve housing and connected to the ball core by a non-cylindrical portion and a cylindrical portion extending from the non-cylindrical portion towards the interior bore of the ball core. Preferably, the cylindrical portion terminates inwardly in a curved portion fitting the interior bore of the ball core.

Abstract: A method of repairing a drill pipe having first and second connector ends, each of the first and second connectors ends including a threaded portion and sealing portions, with a lathe having a chuck with longitudinally spaced first and second sets of jaws, the method comprising the steps of mounting the drill pipe in a lathe, gripping the first connector end of the drill pipe with each of the first and second sets of jaws, orienting the first connector end by manipulation of the first and second sets of jaws into a working position; and rotating the drilling pipe against a working tool to machine the threaded portion and sealing portion of the first connector end and produce a new threaded portion and sealing portion of the first connector end. A lathe with longitudinally spaced first and second sets of jaws is also disclosed. A device for positioning of subsequent workpieces without repeating alignment steps is also disclosed.