Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21D41/00—Application of procedures in order to alter the diameter of tube ends
  • B21D41/04—Reducing; Closing
  • B21D41/045—Closing

Definitions

• This invention relates to a method of crushing a tube.
• the invention has particular, but not exclusive, application in preparing the end of a tube for connection with another member via a conventional fixing element such as a bolt.
• web is used to refer to a strut or bracing element which extends between the upper and lower chord of a roof truss.
• the invention resides in a method of crushing a tube, the method including:- pressing together opposed portions of the tube such that the opposed portions abut to define a land which is adapted to receive a fixing element, wherein opposed lateral portions of the tube adjacent the land do not abut but rather define sub-tubes which straddle the land and which extend lengthwise of the tube.
• the invention resides in a method of forming a flattened region in a tube, the method including pressing together opposed portions of the tube, whilst not pressing together lateral opposed portions of the tube.
• the invention resides in a method of forming a flattened region in a tube, the method including selectively pinching opposed portions of the tube together such that the opposed portions of the tubes abut at a central location and such that lateral sub-tubes are defined which straddle the pinched portion.
• the invention resides in a method of forming a land on a tube, the method including:- compressing opposed peripheral portions into abutment to define the land, such that lateral ribs extend along either side of the land, the ribs being formed by the portions of the tube adjacent the abutting portions which define the land.
• the invention resides in a method of crushing a tube, the method including:- crushing the tube between a pair of opposed crush members, at least one of the crush members being substantially narrower than the corresponding dimension of the tube and engaging the tube in a substantially central location whereby a central crushed region is defined between a pair of lateral non- crushed regions, said crushed region being adapted to receive a fixing element.
• the invention resides in a tube including a crushed region wherein opposed portions of the tube have been crushed together to abut and define a land which is adapted to receive a fixing element, the tube further including longitudinally extending non-crushed regions located laterally either side of the crushed region.
• the invention resides in a tube including:- a land at an end of the tube formed by compressing opposed peripheral portions of the tube into abutment, and ribs extending along either side of the land and formed by the portions of the tubular member adjacent the abutting peripheral portions.
• FIG 1 is a plan view of a tube having a crushed or flattened end
• FIG 2 is a frontal elevation of the tube of FIG 1 ;
• FIG 3 is a right side elevation of the tube of FIG 1 with a bolt head present
• FIG 4 is a right side elevation of the tube of FIG 1 with the bolt head absent; and FIG 5 is a right side elevation of the tube of FIG 1 with the nut and bolt present and with the tube fastened to a planer surface.
• Tube 10 may be, for example, a web which in use extends between the upper and lower chords of a roof truss.
• Tube 10 is originally formed from a planer sheet of material which is folded about a longitudinal axis to define the tube with an overlapping longitudinal seam 12 as best shown in FIG 2.
• the seam may be welded, riveted, glued or fixed by any known means.
• the preferred embodiment utilises an integral stitching method which swages together material in the overlapping seam region.
• the end of the tube is tapered in frontal elevation.
• a substantially triangular region 14 is more aggressively tapered and is pressed together into an abutting relationship adjacent the end of the tube.
• a central region 18 the opposed peripheral portions of the tube are crushed together so as to be abutting and planer.
• open sections 20 are defined either side of the central crushed region 18.
• Each of the open sections 20 defines a sub-tube or rib which extends longitudinally of the tube 10 either side of the central crushed region 18.
• the central crushed region 18 is adapted to receive a fixing element by virtue of one or more punched holes 16. As shown in FIG 3, the punched hole 16 receives a fixing element in the form of a nut and bolt arrangement 22.
• the central crushed region 18 provides a flattened land which is adapted to receive a conventional fixing element such as nut and bolt arrangement 22.
• the lateral non-crushed regions 20 provide additional structural strength as compared to a tube in which the entire end of the tube is pinched into an abutting relationship.
• a planer surface eg the upper or lower chord of a truss
• the end of the tube is deformed in that ribs or sub-tubes 20 are deformed upwardly in a wing-like manner by virtue of the engagement of the underside of the tube with the planer surface of the chord.
• upward wing-like deformation of the sub-tubes 20 occurs under load, ie. the bolt is under tension as it is tightened. This results in a secure joint between the tube and chord.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Joining Of Building Structures In Genera (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (1)

Family

ID=3817418

Family Applications (1)

Country Status (5)

Cited By (3)

Citations (4)

Family Cites Families (3)

• 1999
  • 1999-10-05 AU AUPQ3258A patent/AUPQ325899A0/en not_active Abandoned
• 2000
  • 2000-10-05 EP EP00969073A patent/EP1222041A4/en not_active Withdrawn
  • 2000-10-05 WO PCT/AU2000/001209 patent/WO2001024955A1/en not_active Application Discontinuation
  • 2000-10-05 CA CA002386364A patent/CA2386364A1/en not_active Abandoned
  • 2000-10-05 JP JP2001527940A patent/JP2003511236A/ja not_active Withdrawn

Patent Citations (4)

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