Static structures (e.g. – buildings) – Machine or implement
Reexamination Certificate
1998-04-07
2001-04-24
Kent, Christopher T. (Department: 3635)
Static structures (e.g., buildings)
Machine or implement
C052S749100
Reexamination Certificate
active
06219990
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method of making metal I-beams of the type employed in building construction and the associated I-beam and, more specifically, it relates to improved hot rolled metal I-beams which resist the formation of undesired waves in the I-beam web and the method of making the same.
2. Description of the Prior Art
It has long been known to employ various types of metal beams, such as steel I-beams, in building construction of various types. Such beams have a web and a pair of flanges in opposite edges of the web such that the beams may be employed individually or in an assembly of such beams so as to safely support substantial static loads thereon.
It has been known to establish such beams by welding the flanges to the web. It has also been known to form such beams by hot rolling from a billet.
One of the problems which has been encountered with respect to hot roll forming of I-beams has resulted from the bulk distribution causing the web temperature and the flange temperature to be sufficiently different that the web cools faster than the flange thereby resulting in undesirable waves being created in the web due to the differential cooling rate. This temperature differential can, in some instances, equal about 250° F.
U.S. Pat. No. 4,251,973 discloses an I-beam welded to flanges wherein an effort to cure the problem of web waviness due to temperature differential is disclosed. It employs a plurality of hollow corrugations formed within the web extending in a direction generally perpendicular to the longitudinal extent of the I-beam. See, also, German Patent 46414.
It has also been known to suggest providing open trusses for building construction wherein elongated truss ribs are initially formed within the web and are subsequently severed from major portions of the web and deformed to create the expanded open web truss construction. See U.S. Pat. Nos. 1,927,442 and 3,962,763.
U.S. Pat. No. 3,199,174 discloses securing a series of flat strips to the web to resist undesired web buckling “at the manufacture of the beam” and to strengthen the web against buckling caused by external forces.
It has also been known to provide a truss with a plurality of indentations in the web separated by elongated bars.
U.S. Pat. No. 2,263,272 discloses the manufacture of a steel I-beam by welding a web plate to a pair of T-sections.
U.S. Pat. No. 4,129,974 discloses an I-beam having a restraining structure in the form of a local reinforcing member which is generally channel-shaped and secured to the flanges and web at a particular longitudinal position. See, also, U.S. Pat. No. 2,392,674.
Reinforcement of a leading end of a pile member through the use of one or more weld beads is disclosed in U.S. Pat. No. 3,810,363.
In spite of the foregoing disclosures, there remains a real and substantial need for a method of making a metal I-beam by hot rolling without the presence of undesired waves in the web portion and the resultant product, as well as a building construction and other structural products employing one or more such I-beams in a load bearing manner.
SUMMARY OF THE INVENTION
The present invention has solved the above-described problem by providing a method of creating a metal I-beam by hot rolling. An elongated metal workpiece is progressively hot rolled to create an elongated beam having a web and flanges at the edges thereof. Within the web are formed elongated reinforcing means of solid cross-section having a generally straight longitudinal axis oriented generally parallel to the flanges. Cooling of the I-beam is then accomplished while resisting forming of substantial waves in the web. The method contemplates the elongated reinforcing means in a preferred embodiment being about one to five elongated laterally projecting ribs which are preferably continuous and coextensive with the beams. The reinforcing ribs serve as a heat sink to minimize the temperature differential between the web and the flanges during roll forming such that cooling does not create temperature differential induced waves in the web.
In a preferred embodiment the ribs are established with a maximum width of about 200 to 400 percent of the average width of the web and preferably about 275 to 325 percent. The height measured along the web is about 0.5 to 1.5 inches and preferably about 0.75 to 1.25 inches.
The hot rolling is preferably effected sequentially at multiple stations at a temperature of about 1800° F. to 2300° F. for steel I-beams. Prior to cooling, it is common for the temperature of the web be about 85 to 95 percent of the temperature of the flanges.
The I-beam made by the foregoing method has the described construction and is substantially devoid of temperature differential induced waviness in the web.
The resultant beam may be employed in a building as a load bearing member in the same manner as any I-beam could be employed.
It is an object of the present invention to provide a method of hot rolling an I-beam and the resultant product which resists temperature induced waviness in the web portion of the I-beam.
It is a further object of the present invention to provide longitudinally extending reinforcing means integrally formed within the I-beam web which function as a heat sink to minimize temperature differential between the web and flanges during I-beam roll forming.
It is a further object of the present invention to provide such a method of making an I-beam which may be employed with conventional roll forming techniques with rolls appropriately designed to establish the reinforcing means.
It is another object of the present invention to provide such a method and resultant product which may be employed in a conventional manner in load bearing use in building construction.
It is yet another object of the present invention to provide such a method and an associated product which are economical to manufacture and use.
It is yet another object of the invention to provide such an I-beam which has reduced weight per linear foot as compared with standard I-beams while having equal or increased strength.
REFERENCES:
patent: 101015 (1870-03-01), Holms
patent: 1837088 (1931-12-01), Watson
patent: 1927442 (1933-09-01), Laufle
patent: 2056563 (1936-10-01), Budd et al.
patent: 2108795 (1938-02-01), Budd et al.
patent: 2246578 (1941-06-01), Salardi
patent: 2263272 (1941-11-01), Moss
patent: 2392674 (1946-01-01), Lachman et al.
patent: 2605867 (1952-08-01), Goodwin
patent: 3199174 (1965-08-01), Nilsson et al.
patent: 3217659 (1965-11-01), Ford, Jr.
patent: 3335596 (1967-08-01), Noda et al.
patent: 3810363 (1974-05-01), Dar Conte
patent: 3962763 (1976-06-01), Jury
patent: 4129974 (1978-12-01), Ojalvo
patent: 4251973 (1981-02-01), Paik
patent: 4291564 (1981-09-01), Muckli
patent: 4433565 (1984-02-01), Preller
patent: 5203183 (1993-04-01), Iguchi et al.
patent: 5518208 (1996-05-01), Roseburg
patent: 5623845 (1997-04-01), Wilde
patent: 58-116901 (1983-07-01), None
patent: 606201 (1985-01-01), None
patent: 63-299801 (1988-12-01), None
patent: 531501 (1993-02-01), None
Karczewski Michael A.
Saigal Sunil
Shurskis Karl W.
Snyder Carl A.
Eckert Seamans Cherin & Mellott , LLC
J&L Structural, Inc.
Kent Christopher T.
Silverman Arnold B.
Thissell Jennifer I.
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