Tool device for expanding the end of a tube

A tool device for expanding the end of a tube (T) includes an expansion sleeve element made of elastomeric material, the expansion sleeve element being arranged concentrically around a pull rod. A calibration sleeve is arranged concentrically around the expansion sleeve element. The inner die surface of the calibration sleeve comprises a mouth portion which has a fourth diameter (d4) which corresponds with a play to the outer diameter of the tube (T), at least one expansion die portion having a fifth diameter (d5, d6) which is larger than the fourth diameter (d4), and a shoulder between the mouth portion and the expansion die portion. The shoulder keeps the end of the tube (T), while being expanded, stationary in place inside the calibration sleeve. The calibration sleeve comprises mutually openable and closable calibration sleeve parts to enable closing of the calibration sleeve to a closed position (III) for the expanding operation of the end of the tube, and for opening of the calibration sleeve to an opened position (IV) for releasing the expanded end of the tube.