Claims
- 1. An elongate structural member formed from a single strip of metal by a continuous cold rolling process, the structural member comprising:
- an intermediate web member and hollow flanges extending longitudinally of the intermediate web member; characterized in that
- the hollow flanges are of a predetermined shape and are formed by successively deforming free edge portions of a planar strip of metal in a roll forming mill in a continuous operation followed by continuous seam welding of the respective free edges of the shaped hollow flange portions to the surface of the intermediate web member adjacent the junction of the web member and respective hollow flange portions; and
- the free edges of the hollow flange portions are welded to the surface of the intermediate web member by high frequency electrical induction or resistance welding.
- 2. A structural member as claimed in claim 1 wherein the hollow flanges are of different cross-sectional shapes.
- 3. A structural member as claimed in claim 1 wherein the hollow flanges are of different cross-sectional areas.
- 4. A structural member as claimed in claim 1 wherein at least one hollow flange has a symmetrical triangular cross-sectional shape.
- 5. A structural member as claimed in claim 4 wherein both hollow flanges have a symmetrical triangular cross-sectional shape of substantially the same cross-sectional area.
- 6. A structural member as claimed in claim 1 wherein at least one hollow flange has a circular cross-sectional shape.
- 7. A structural member as claimed in claim 1 wherein the free edges of the hollow flange portions are welded substantially perpendicular to the surface of the intermediate web.
- 8. A structural member as claimed in claim 7 in which the hollow flange portions have been roll-formed to their final shape after being welded to the intermediate web member.
- 9. A structural member as claimed in claim 1 further comprising a prestressing member extending longitudinally through one of the hollow flanges.
Priority Claims (3)
Number |
Date |
Country |
Kind |
PI9427 |
Jul 1988 |
AUX |
|
PJ1534 |
Nov 1988 |
AUX |
|
PCT/AU89/00313 |
Jul 1989 |
WOX |
|
Parent Case Info
This is a continuation of application Ser. No. 07/923,578 filed Aug. 3, 1992 and now abandoned, which in turn is a division of application Ser. No. 07/875,610 filed Apr. 28, 1992, now U.S. Pat. No. 5,163,225, which is a continuation of application Ser. No. 07/762,174 filed Sep. 20, 1991 and now abandoned, and which is a continuation of application Ser. No. 07/459,713 filed Dec. 14, 1989, and now abandoned.
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Non-Patent Literature Citations (4)
Entry |
Russian Text Reference-"Prestressed Steel Structures", Ferentschik et al., 1979 How HF Forge Welding Works For You, Welded Beam Corp. |
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Divisions (1)
|
Number |
Date |
Country |
Parent |
875610 |
Apr 1992 |
|
Continuations (3)
|
Number |
Date |
Country |
Parent |
923578 |
Aug 1992 |
|
Parent |
762174 |
Sep 1991 |
|
Parent |
459713 |
Dec 1989 |
|