Internal chuck for butt welding two tubes

摘要

An internal chuck for use in the butt welding of tubes 16, 17 aligning the tubes and for bringing them into abutment comprises a central tube 6, a sleeve 7 slidable on the central tube and carrying centering means 12 and welding backup means 8, the centering means and the welding backup means being longitudinally spaced from one another, gripping means 2, and jaws 33 for clamping against the tubes. The jaws are displaceable longitudinally relative to the gripping means and central tube to draw the two tubes together and a jack 27 is provided for displacing the sleeve longitudinally relative to the central tube so that either the centering means or the welding backup means can be aligned with the ends of the tubes.