Abstract: A seal device for a hydroforming press includes a housing having a cylindrical bore and a cylindrical seal carrier slidable within the housing bore. The seal carrier has a bore and a tube support which fit closely on outside and inside of the end of the tube to be hydroformed. An actuator is operable to forcibly move the seal carrier from a retracted position withdrawn away from the end of the tube to an extended position in which the seal carrier is installed over the end of the tube. A resilient elastomeric annular seal is carried by the seal carrier and encircles the outer circumference of the tube with some clearance. A seal actuator carried on the seal carrier compresses the seal upon relative movement between the seal actuator and the seal carrier so that the seal is forced radially inwardly to seal against the tube.