Stock material or miscellaneous articles – All metal or with adjacent metals – Intermediate article
Reexamination Certificate
1999-10-13
2001-07-31
Zimmerman, John J. (Department: 1775)
Stock material or miscellaneous articles
All metal or with adjacent metals
Intermediate article
C428S598000, C228S153000, C228S164000, C228S184000
Reexamination Certificate
active
06268066
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates to an improved process of welding and more particularly to an improved process for making a burner box made of stainless steel.
SUMMARY OF THE INVENTION
A process for making certain stainless steel rectangular boxes with flanges is disclosed using a tungsten inert gas process. This welding process applies to all ferrous metals. The integrity of the burner box requires leak-proof construction. The burner box is rectangular with flanges and holes and two end plates, all of which are joined by the gas tungsten arc welding process. The end plates overlap the entire periphery of the ends of the body by half of the metal thickness thereby acting as a heat sink and allowing the excess (overlap) material to be melted and used as filler. Tabs are provided on end plates, which become part of the finished product, and provides additional material to be catalyzed as part of the weld in the corners where blow out generally occurs in manual welding, particularly in thin sheet materials. The tab provides positive location of the end plate.
A special high chrome content, stainless steel was developed by Allegheny-Ludlum, AL-29-4C for the purpose of withstanding and containing noxious gases created in the furnace heat exchanger.
A method is provided for welding thin sheets of stainless steel into, for example, rectangular boxes with flanges automatically welded using the tungsten arc inert gas process on relatively thin sheet metal.
An application for this method is in welding a special high chrome content, stainless steel, specifically Allegheny-Ludlum, AL-29-4C, for the purpose of withstanding and containing noxious gases created in a furnace heat exchanger. Prior to applicant's invention no one has been able to automatically weld this sheet of stainless steel into gas tight containers without blow through. This welding process is applicable to all ferrous metals. The integrity of a burner box requires leak-proof construction. The burner box disclosed herein consists of a three sided rectangle with flanges and holes and two end plates, all of which are joined by a gas tungsten arc process. The drawing suggested that manual welding would be required. Development commenced to cause the burner boxes to be manufactured with an automatic welding machine.
The blank required special tooling and design to maintain tolerances of 0.003 of an inch for all critical dimensions so that the automatic welding process could be introduced.
To provide leak-proof construction the end plate was designed to overlap the entire periphery of the part body by one half of the metal thickness thereby acting as a heat sink and allowing the excess overlap material to be used as filler. The corners present a particularly difficult problem. At each corner a tab is designed and cut as part of the end plate in the finished product, which allows additional material to be integrated as part of the weld in the corners where blow out generally occurs in manual welding. The tab provides positive location of the end plate. Without the design of the blank and holding its tolerances, manual welding would be required.
Special tooling has been designed and installed on a commercial automatic welding machine. A special software program may be created to cause the machine to weld in the right places. The tooling contains a fixture, which requires a positive dimensional check on the blank. The end plate is inserted on the top of the blank, centered by the fixture and welded automatically. The piece may be turned upside down on a second fixture so that the other end plate may be attached.
It is an object of the present invention to provide an improved structure of a box.
It is another object of the present invention to provide an improved method of making a box.
It is another object of the present invention to provide a box that is simple in construction, economical to manufacture, and simple and efficient to use.
With the above and other objects in view, the present invention consists of the combination and arrangement of parts hereinafter more fully described, illustrated in the accompanying drawing and more particularly pointed out in the appended claims, it being understood that the changes may be made in the form, size, proportions and minor details of construction without departing from the spirit or sacrificing any of the advantages of the invention.
REFERENCES:
patent: 782417 (1905-02-01), Robb
patent: 926246 (1909-06-01), Dorff
patent: 3440711 (1969-04-01), Roper
patent: 3633786 (1972-01-01), Leedy
patent: 4728126 (1988-03-01), Sundholm
patent: 5090612 (1992-02-01), Jones
patent: 5221585 (1993-06-01), Kresse, Jr. et al.
patent: 5337033 (1994-08-01), Kinouchi et al.
patent: 5811756 (1998-09-01), Horita et al.
patent: 6060682 (2000-05-01), Westbroek et al.
patent: 2-41718 (1990-02-01), None
patent: 4-237563 (1992-08-01), None
Lovercheck and Lovercheck
Zimmerman John J.
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