Method and apparatus for pulling tubes from heat exchanger baffles

Claim 1

Apparatus for pulling tubes from a tube bundle, which includes at least one baffle plate through which a plurality of such tubes tightly pass, said apparatus comprising: a. A cradle for securely supporting the tube bundle against axial movement of the whole tube bundle when a tube is being pulled axially therefrom; b. a gripper unit, including means for releasably gripping a tube to be pulled out; c. a tool platform having said gripper unit mounted thereon; d. a fixed frame; e. means movably mounting the tool platform on the fixed frame for transverse movement to bring the gripper unit to an address where it is in axial alignment with any selected one of the tubes that is to be pulled out next; f. axially extensible-retractile means interconnecting the gripper unit and tool platform, for thrusting the gripper unit axially forwards into adjacency with the tube bundle and for pulling a gripped tube axially from the bundle; g. means interconnecting the gripper unit and said axially extensible-retractile means for axially advancing the gripper unit into gripping relation with the tube that is to be gripped and pulled from the bundle in the next pull; h. means for sensing that the first axially extensible-retractile means is fully retracted, and, in response to such sensation, releasing the gripper unit from gripping relation to the tube and extending the first axially extensible-retractile means until the gripper unit is thereby thrust into adjacency with the tube bundle; i. stop means stationed to engage with each tube when that tube is partially withdrawn in a sense to prevent reverse axial travel of that tube back toward the tube bundle; j. means for sensing whether, when the gripper unit has been thrust into adjacency with the tube bundle, I. the gripper unit remains beside an axially further upstream portion of the same tube the gripper unit had just pulled axially from the bundle or Ii. the gripper unit no longer remains beside a tube, meaning that the tube the gripper unit had just pulled axially from the bundle has been completely withdrawn and advanced past the gripper unit, and if (I) is sensed, signal the axially extensible-retractile means to automatically place the gripper unit in gripping relation with the pipe again and fully retract again, but if (II) is sensed, await readdressing of the tool platform.