Abstract: An apparatus and method for piercing a hole in a work piece suitable for hydroforming applications is provided. The apparatus includes first and second die portions forming a die cavity for the work piece. Each die includes a punch cavity generally perpendicular to the work piece. One of the punch cavities has a slug capturing area. A punch with an angular cutting face can be moved within a cross passage created by the punch cavities to impact the work piece. The angular cutting face of the punch has a larger surface area than the punch body, which results in expanding slugs pierced from the work piece. The slug capturing area is configured with a cross-sectional area smaller than the surface area of the angular cutting face.

Abstract: A tool forms a threaded hole in a hydroformed part while the part remains in a hydroforming die cavity and under pressure. The tool has a hole-piercing end portion adapted on advancement of the tool to pierce and form a hole in the part and an extruding portion adapted on continued tool advancement to extrude an annular extrusion that extends into the tube interior. An adjacent sealing portion of the tool seals the hole during the ongoing advancement and extrusion of the annular extrusion so that hydroforming fluid remains under pressure. A thread-forming portion of the tool forms an internal thread within the annular extrusion upon the continued advancement and rotation of the tool.

Abstract: A method is provided for joining tubes. An outer tube and an inner tube are provided. An end of the inner tube is inserted into an end of the outer tube to form an overlapped region of tube wall and form a pressure tight joint between the tubes. The overlapped region of the tubes is heated. The tubes are placed in pair of dies having a die cavity adjacent to the outer tube. Pressure is introduced into the tubes to expand the overlapped region of the tubes outwardly into the die cavity and thereby form an interlocking joint between the overlapped region of the outer tube and the inner tube.

Abstract: Apparatus is provided for punching holes through the opposed first and second tube walls of a hydroformed tube while the tube is within the die cavity formed by a pair of hydroforming dies. A punch is mounted within a punch bore that intersects with the die cavity. A punch advances the punch to punch a first hole in the first tube wall and then travel across the die cavity and make a second hole in the second tube wall. A support mechanism for supporting the second wall of the tube against rupture by the hydroforming pressure includes spring biasing a support face of a support rod into engagement with the second wall and yielding during the punching of the second hole. A support rod actuator withdraws the support rod to carry the support face away from the second wall after the second hole is punched.

Abstract: A mandrel assembly is provided for insertion into a hollow tube to support the interior walls of the tube during bending of the tube in a tube bending apparatus. The mandrel assembly includes at least one mandrel segment that is adapted for positioning within the tube and has an exterior support surface for supporting the interior walls of the tube during bending. The mandrel segment is anchored at a fixed axial location within the tube by an anchoring device that is radially expandable and retractable between an expanded condition in which an anchor shoe is engaged with the interior wall of the tube and a retracted condition in which the anchor shoe is loose within the tube. A mandrel support rod is attached to the anchoring device for inserting and withdrawing the anchoring device into the tube when the anchor shoe is retracted.

Abstract: A tool forms a threaded hole in a hydroformed part while the part remains in a hydroforming die cavity and under pressure. The tool has a hole-piercing end portion adapted on advancement of the tool to pierce and form a hole in the part and an extruding portion adapted on continued tool advancement to extrude an annular extrusion that extends into the tube interior. An adjacent sealing portion of the tool seals the hole during the ongoing advancement and extrusion of the annular extrusion so that hydroforming fluid remains under pressure. A thread-forming portion of the tool forms an internal thread within the annular extrusion upon the continued advancement and rotation of the tool.

Abstract: A mandrel assembly is provided for insertion into a hollow tube to support the interior walls of the tube during bending of the tube in a tube bending apparatus. The mandrel assembly includes at least one mandrel segment that is adapted for positioning within the tube and has an exterior support surface for supporting the interior walls of the tube during bending. The mandrel segment is anchored at a fixed axial location within the tube by an anchoring device that is radially expandable and retractable between an expanded condition in which an anchor shoe is engaged with the interior wall of the tube and a retracted condition in which the anchor shoe is loose within the tube. A mandrel support rod is attached to the anchoring device for inserting and withdrawing the anchoring device into the tube when the anchor shoe is retracted.

Abstract: A hydroform seal assembly includes a seal housing and an annular nozzle carried by the seal housing and sized to insert into a tube end. A first actuator moves the seal housing to insert the nozzle. A plurality of jaws are carried by the seal housing and are movable radially inward into clamping engagement with the tube to clamp the tube onto the annular nozzle. A cam bushing is movably mounted within the seal housing, surrounds the jaws, and has cam surfaces complimentary with cam surfaces provided on the jaws so that movement of the cam bushing relative the jaws will cam the jaws radially inward. A backup cam is movable within the seal housing. The cam bushing and backup cam have complimentary cam surfaces by which movement of the backup cam will forcibly move the cam bushing relative the seal housing. A second actuator moves the backup cam.

Abstract: An apparatus and method for locally expanding tubular member includes a pre-form die having a cavity with an expansion chamber therein to receive a portion of a tubular blank between ends thereof. The apparatus also includes a bladder apparatus for insertion in the tubular blank and cooperating with the pre-form die to locally expand the portion of the tubular blank in the expansion chamber to form a locally expanded tubular member.

Abstract: An apparatus and method for hydroshearing and hydrotrimming for a hydroforming die includes a cutting insert fixed relative to the hydroforming die. The apparatus and method also includes a disposable insert fixed relative to the hydroforming die. The apparatus and method further includes a plunger movable relative to the hydroforming die to allow fluid within a tubular member to force a wall portion of the tubular member outward against the plunger and be sheared in the hydroforming die to trim the tubular member.

Abstract: A method is provided for hydroforming a ring-shaped tubular structure such as a door opening for a vehicle body. The method includes providing a ring-shaped tubular blank having a hollow sealed interior, capturing the ring shaped tubular blank in a hydroforming die cavity, piercing the ring shaped tubular blank with a hollow punch, and introducing pressurized fluid through the hollow punch into the hollow sealed interior to expand the tubular structure to conform with the shape of the hydroforming die cavity and thereby hydroform the ring-shaped tubular structure.

Abstract: A punch for a hydroforming die includes a body, a neck extending axially from the body, a head extending axially from the neck and having a diameter less than a diameter of the body and a thumbnail slot extending axially and radially into the head to allow fluid within a tubular member to force a wall portion of the tubular member outward into the slot of the punch and be sheared by the punch to produce an opening in the tubular member.

Abstract: A punch assembly used with a hydroforming die includes a punch cylinder for mounting to the hydroforming die and having a movable rod. The punch assembly also includes a punch for piercing an opening in a tubular member disposed in the hydroforming die. The punch assembly further includes a quick change assembly interconnecting the rod of the punch cylinder and the punch for allowing the punch to be removably attached to the punch cylinder.

Abstract: A double action punch assembly for a hydroforming die includes a first punch segment having an aperture extending therethrough. The double action punch assembly also includes a movable mounting block disposed in the aperture of the first punch segment. The double action punch assembly further includes a plurality of second punch segments connected to the mounting block. The first punch segment is moved in a first action to pierce a tubular member in a first direction and the second punch segments are moved in a second action to pierce the tubular member in a second direction to produce an opening in the tubular member.

Abstract: A clamp assembly for a hydroforming die includes a stationary lower bed to support a lower die half of the hydroforming die, a stationary upper bed spaced above the lower bed, at least one guide post extending between the lower bed and the upper bed, a movable slide disposed between the upper bed and the lower bed and movable along the at least one guide post to support an upper die half of the hydroforming die, a lifting cylinder operatively connected to the movable slide to move the movable slide and upper die half toward and away relative to the lower die half, at least one link mechanism connected to the upper bed and the movable slide to equalize a force on the hydroforming die, and at least one linkage cylinder operatively connected to the at least one link mechanism to activate the at least one link mechanism to prevent the movable slide and upper die half from moving away from the lower die half to keep the hydroforming die closed during a hydroforming process.

Abstract: A punch assembly for a hydroforming die includes a servo motor, a ball screw connected to the servo motor, and a ball nut disposed about the ball screw for movement along the ball screw. The punch assembly also includes a link mechanism connected to the ball nut and a plunger operatively connected to the link mechanism and movable relative to the hydroforming die to allow fluid within a tubular member to force a wall portion of the tubular member outward against the plunger and be sheared by the hydroforming die to produce an opening in the tubular member.

Abstract: A center support punch assembly for a hydroforming die includes a center support member for fixed attachment to a die. The center support punch assembly also includes a button disposed about and space from the center support member for fixed attachment to the die. The center support punch assembly further includes a plunger movable relative to the center support member to allow fluid within a tubular member to force a wall portion of the tubular member outward against the center support member and be sheared by the button to produce an opening in the tubular member.