Method and tool for extracting and inserting heat exchanger tubes

Claim 1

MEANS FOR SIMULTANEOUSLEY EXTRACTING AN OLD HEAT EXCHANGER TUBE FROM ITS POSITION WITHIN THE OPENINGS IN SPACED TUBE SHEETS AND REPLACING IT WITH A NEW TUBE, SAID MEANS COMPRISING A MANDREL DEVICE CONSISTING OF A PAIR OF INTERENGAGEABLE MANDREL RODS, EACH OF SAID RODS BEING OF SOMEWHAT GREATER LENGTH THAN THAT OF ONE OF THE TUBES AND OF AN OUTSIDE DIAMETER BUT SLIGHTLY SMALLER THAN THE INSIDE DIAMETER OF THE TUBES, NO PART OF EITHER ROD BEING OF GREATER DIAMETER THAN THE INSIDE DIAMETER OF SAID TUBES, ONE OF SAID RODS ADAPTED TO BE INSERTED WITHIN THE OLD TUBE WITH ONE OF ITS ENDS PROTRUDING FROM THE OLD TUBE IN THE DIRECTION OF WITHDRAWAL OF THE TUBE, AND ITS OTHER END AT THE OPPOSITE END OF THE OLD TUBE PROVIDED WITH A LONGITUDINALLY EXTENDING BEVELLED SURFACE; THE OTHER OF SAID RODS ADAPTED TO BE INSERTED WITHIN THE NEW TUBE WITH ONE OF ITS ENDS PROTRUDING FROM THE NEW TUBE IN THE DIRECTION OPPOSITE TO THE REPLACING MOVEMENTS OF THE NEW TUBE, THE OTHER END OF THE SECOND NAMED ROD AT THE OPPOSITE END OF THE NEW TUBE BEING PROVIDED WITH A LONGITUDINAL BEVELLED SURFACE COMPLEMENTARY TO THE BEVELLED SURFACE OF THE FIRST NAMED ROD AND INTERFITTING THEREWITH WHEN THE OLD AND NEW TUBES ARE BROUGHT INTO END-ABUTTING RELATIONSHIP; THE WEDGING INTERFIT OF THE BEVELLED ENDS OF THE RODS SERVING TO EFFECT INTERNAL GRIPPING OF THE TUBES FOR LONGITUDINAL FORCED MOVEMENT THEREOF AND AT THE SAME TIME TO BUTTRESS THE WALLS OF BOTH TUBES TO PREVENT DISTORTION OF THE TUBE WALLS AS THEY ARE FORCED SIMULTANEOUSLY THROUGH THE OPENINGS IN THE TUBE SHEETS, A PROTRUDING END OF SAID SECOND NAMED ROD BEING PROVIDED WITH A SHOULDER DEPRESSED WITHIN ITS PERIPHERY WHICH IS ADAPTED TO BE IMPACTED IN THE OPPOSITE DIRECTION TO THE MOVEMENT OF THE TUBES IN ORDER TO BREAK THE WEDGING INTERLOCK OF THE BEVELLED ROD ENDS, AS WHEN THE NEW TUBE IS ULTIMATELY IN PLACE.

Claim 3

THE METHOD OF SIMULTANEOUSLY REMOVING AN OLD HEAT EXCHANGER TUBE FROM ITS TUBE SHEETS AND INSERTING A NEW TUBE IN ITS PLACE, WHICH COMPRISES END-ABUTTING THE TWO TUBES; INSERTING AN EXPANSION MANDREL THROUGH THE ALIGNED TUBES; EXPANDING THE MANDREL IN THE VICINITY OF THE ABUTTING TUBE ENDS, ONLY TO THE POINT OF OBTAINING WEDGING INTERLOCING OF THE TUBES AND EXPANSION MANDREL AND THE REINFORCEMENT OF THE TUBE WALLS AGAINST DISTORTION; AND THEN APPLYING FORCE TO THE RESULTING ASSEMBLY OF TUBES AND EXPANSION MANDREL IN THE DIRECTION LONGITUDINALLY OF THE TUBES TO SLIDINGLY REMOVE THE OLD TUBE AND BRING THE NEW ONE INTO POSITION.

Claim 4

THE METHOD OF SIMULTANEOUSLY REMOVING AN OLD HEAT EXCHANGER TUBE FROM ITS TUBE SHEETS AND INSERTING A NEW TUBE IN ITS PLACE, WHICH COMPRISES END-ABUTTING THE TWO TUBES; INSERTING AN EXPANSION MANDREL THROUGH THE ALIGNED TUBES; EXPANDING THE MANDREL IN THE VICINITY OF THE ABUTTING TUBE ENDS, ONLY TO THE POINT OF OBTAINING WEDGING INTERLOCING OF THE TUBES AND EXPANSION MANDREL AND THE REINFORCEMENT OF THE TUBE WALLS AGAINST DISTORTION; AND THEN APPLYING FORCE TO THE RESULTING ASSEMBLY OF TUBES AND EXPANSION MANDREL IN THE DIRECTION LONGITUDINALLY OF THE TUBES TO SLIDINGLY REMOVE THE OLD TUBE AND BRING THE NEW ONE INTO POSITION.